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 "CGOpenMPRuntime.h"
20 #include "CGRecordLayout.h"
21 #include "CodeGenModule.h"
22 #include "TargetInfo.h"
23 #include "clang/AST/ASTContext.h"
24 #include "clang/AST/Attr.h"
25 #include "clang/AST/DeclObjC.h"
26 #include "clang/Frontend/CodeGenOptions.h"
27 #include "llvm/ADT/Hashing.h"
28 #include "llvm/ADT/StringExtras.h"
29 #include "llvm/IR/DataLayout.h"
30 #include "llvm/IR/Intrinsics.h"
31 #include "llvm/IR/LLVMContext.h"
32 #include "llvm/IR/MDBuilder.h"
33 #include "llvm/Support/ConvertUTF.h"
34 #include "llvm/Support/MathExtras.h"
35 #include "llvm/Transforms/Utils/SanitizerStats.h"
37 using namespace clang;
38 using namespace CodeGen;
40 //===--------------------------------------------------------------------===//
41 // Miscellaneous Helper Methods
42 //===--------------------------------------------------------------------===//
44 llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) {
45 unsigned addressSpace =
46 cast<llvm::PointerType>(value->getType())->getAddressSpace();
48 llvm::PointerType *destType = Int8PtrTy;
50 destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace);
52 if (value->getType() == destType) return value;
53 return Builder.CreateBitCast(value, destType);
56 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
58 Address CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, CharUnits Align,
60 auto Alloca = CreateTempAlloca(Ty, Name);
61 Alloca->setAlignment(Align.getQuantity());
62 return Address(Alloca, Align);
65 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
67 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty,
69 if (!Builder.isNamePreserving())
70 return new llvm::AllocaInst(Ty, nullptr, "", AllocaInsertPt);
71 return new llvm::AllocaInst(Ty, nullptr, Name, AllocaInsertPt);
74 /// CreateDefaultAlignTempAlloca - This creates an alloca with the
75 /// default alignment of the corresponding LLVM type, which is *not*
76 /// guaranteed to be related in any way to the expected alignment of
77 /// an AST type that might have been lowered to Ty.
78 Address CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty,
81 CharUnits::fromQuantity(CGM.getDataLayout().getABITypeAlignment(Ty));
82 return CreateTempAlloca(Ty, Align, Name);
85 void CodeGenFunction::InitTempAlloca(Address Var, llvm::Value *Init) {
86 assert(isa<llvm::AllocaInst>(Var.getPointer()));
87 auto *Store = new llvm::StoreInst(Init, Var.getPointer());
88 Store->setAlignment(Var.getAlignment().getQuantity());
89 llvm::BasicBlock *Block = AllocaInsertPt->getParent();
90 Block->getInstList().insertAfter(AllocaInsertPt->getIterator(), Store);
93 Address CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) {
94 CharUnits Align = getContext().getTypeAlignInChars(Ty);
95 return CreateTempAlloca(ConvertType(Ty), Align, Name);
98 Address CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name) {
99 // FIXME: Should we prefer the preferred type alignment here?
100 return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name);
103 Address CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align,
105 return CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name);
108 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
109 /// expression and compare the result against zero, returning an Int1Ty value.
110 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
111 PGO.setCurrentStmt(E);
112 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
113 llvm::Value *MemPtr = EmitScalarExpr(E);
114 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
117 QualType BoolTy = getContext().BoolTy;
118 SourceLocation Loc = E->getExprLoc();
119 if (!E->getType()->isAnyComplexType())
120 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc);
122 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy,
126 /// EmitIgnoredExpr - Emit code to compute the specified expression,
127 /// ignoring the result.
128 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
130 return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true);
132 // Just emit it as an l-value and drop the result.
136 /// EmitAnyExpr - Emit code to compute the specified expression which
137 /// can have any type. The result is returned as an RValue struct.
138 /// If this is an aggregate expression, AggSlot indicates where the
139 /// result should be returned.
140 RValue CodeGenFunction::EmitAnyExpr(const Expr *E,
141 AggValueSlot aggSlot,
143 switch (getEvaluationKind(E->getType())) {
145 return RValue::get(EmitScalarExpr(E, ignoreResult));
147 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult));
149 if (!ignoreResult && aggSlot.isIgnored())
150 aggSlot = CreateAggTemp(E->getType(), "agg-temp");
151 EmitAggExpr(E, aggSlot);
152 return aggSlot.asRValue();
154 llvm_unreachable("bad evaluation kind");
157 /// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
158 /// always be accessible even if no aggregate location is provided.
159 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
160 AggValueSlot AggSlot = AggValueSlot::ignored();
162 if (hasAggregateEvaluationKind(E->getType()))
163 AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
164 return EmitAnyExpr(E, AggSlot);
167 /// EmitAnyExprToMem - Evaluate an expression into a given memory
169 void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
173 // FIXME: This function should take an LValue as an argument.
174 switch (getEvaluationKind(E->getType())) {
176 EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()),
180 case TEK_Aggregate: {
181 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals,
182 AggValueSlot::IsDestructed_t(IsInit),
183 AggValueSlot::DoesNotNeedGCBarriers,
184 AggValueSlot::IsAliased_t(!IsInit)));
189 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
190 LValue LV = MakeAddrLValue(Location, E->getType());
191 EmitStoreThroughLValue(RV, LV);
195 llvm_unreachable("bad evaluation kind");
199 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
200 const Expr *E, Address ReferenceTemporary) {
201 // Objective-C++ ARC:
202 // If we are binding a reference to a temporary that has ownership, we
203 // need to perform retain/release operations on the temporary.
205 // FIXME: This should be looking at E, not M.
206 if (auto Lifetime = M->getType().getObjCLifetime()) {
208 case Qualifiers::OCL_None:
209 case Qualifiers::OCL_ExplicitNone:
210 // Carry on to normal cleanup handling.
213 case Qualifiers::OCL_Autoreleasing:
214 // Nothing to do; cleaned up by an autorelease pool.
217 case Qualifiers::OCL_Strong:
218 case Qualifiers::OCL_Weak:
219 switch (StorageDuration Duration = M->getStorageDuration()) {
221 // Note: we intentionally do not register a cleanup to release
222 // the object on program termination.
226 // FIXME: We should probably register a cleanup in this case.
230 case SD_FullExpression:
231 CodeGenFunction::Destroyer *Destroy;
232 CleanupKind CleanupKind;
233 if (Lifetime == Qualifiers::OCL_Strong) {
234 const ValueDecl *VD = M->getExtendingDecl();
236 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>();
237 CleanupKind = CGF.getARCCleanupKind();
238 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise
239 : &CodeGenFunction::destroyARCStrongImprecise;
241 // __weak objects always get EH cleanups; otherwise, exceptions
242 // could cause really nasty crashes instead of mere leaks.
243 CleanupKind = NormalAndEHCleanup;
244 Destroy = &CodeGenFunction::destroyARCWeak;
246 if (Duration == SD_FullExpression)
247 CGF.pushDestroy(CleanupKind, ReferenceTemporary,
248 M->getType(), *Destroy,
249 CleanupKind & EHCleanup);
251 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary,
253 *Destroy, CleanupKind & EHCleanup);
257 llvm_unreachable("temporary cannot have dynamic storage duration");
259 llvm_unreachable("unknown storage duration");
263 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
264 if (const RecordType *RT =
265 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
266 // Get the destructor for the reference temporary.
267 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
268 if (!ClassDecl->hasTrivialDestructor())
269 ReferenceTemporaryDtor = ClassDecl->getDestructor();
272 if (!ReferenceTemporaryDtor)
275 // Call the destructor for the temporary.
276 switch (M->getStorageDuration()) {
279 llvm::Constant *CleanupFn;
280 llvm::Constant *CleanupArg;
281 if (E->getType()->isArrayType()) {
282 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
283 ReferenceTemporary, E->getType(),
284 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
285 dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
286 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
288 CleanupFn = CGF.CGM.getAddrOfCXXStructor(ReferenceTemporaryDtor,
289 StructorType::Complete);
290 CleanupArg = cast<llvm::Constant>(ReferenceTemporary.getPointer());
292 CGF.CGM.getCXXABI().registerGlobalDtor(
293 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
297 case SD_FullExpression:
298 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
299 CodeGenFunction::destroyCXXObject,
300 CGF.getLangOpts().Exceptions);
304 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
305 ReferenceTemporary, E->getType(),
306 CodeGenFunction::destroyCXXObject,
307 CGF.getLangOpts().Exceptions);
311 llvm_unreachable("temporary cannot have dynamic storage duration");
316 createReferenceTemporary(CodeGenFunction &CGF,
317 const MaterializeTemporaryExpr *M, const Expr *Inner) {
318 switch (M->getStorageDuration()) {
319 case SD_FullExpression:
321 // If we have a constant temporary array or record try to promote it into a
322 // constant global under the same rules a normal constant would've been
323 // promoted. This is easier on the optimizer and generally emits fewer
325 QualType Ty = Inner->getType();
326 if (CGF.CGM.getCodeGenOpts().MergeAllConstants &&
327 (Ty->isArrayType() || Ty->isRecordType()) &&
328 CGF.CGM.isTypeConstant(Ty, true))
329 if (llvm::Constant *Init = CGF.CGM.EmitConstantExpr(Inner, Ty, &CGF)) {
330 auto *GV = new llvm::GlobalVariable(
331 CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true,
332 llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp");
333 CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty);
334 GV->setAlignment(alignment.getQuantity());
335 // FIXME: Should we put the new global into a COMDAT?
336 return Address(GV, alignment);
338 return CGF.CreateMemTemp(Ty, "ref.tmp");
342 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner);
345 llvm_unreachable("temporary can't have dynamic storage duration");
347 llvm_unreachable("unknown storage duration");
350 LValue CodeGenFunction::
351 EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
352 const Expr *E = M->GetTemporaryExpr();
354 // FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so
355 // as that will cause the lifetime adjustment to be lost for ARC
356 auto ownership = M->getType().getObjCLifetime();
357 if (ownership != Qualifiers::OCL_None &&
358 ownership != Qualifiers::OCL_ExplicitNone) {
359 Address Object = createReferenceTemporary(*this, M, E);
360 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
361 Object = Address(llvm::ConstantExpr::getBitCast(Var,
362 ConvertTypeForMem(E->getType())
363 ->getPointerTo(Object.getAddressSpace())),
364 Object.getAlignment());
365 // We should not have emitted the initializer for this temporary as a
367 assert(!Var->hasInitializer());
368 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
370 LValue RefTempDst = MakeAddrLValue(Object, M->getType(),
371 AlignmentSource::Decl);
373 switch (getEvaluationKind(E->getType())) {
374 default: llvm_unreachable("expected scalar or aggregate expression");
376 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false);
378 case TEK_Aggregate: {
379 EmitAggExpr(E, AggValueSlot::forAddr(Object,
380 E->getType().getQualifiers(),
381 AggValueSlot::IsDestructed,
382 AggValueSlot::DoesNotNeedGCBarriers,
383 AggValueSlot::IsNotAliased));
388 pushTemporaryCleanup(*this, M, E, Object);
392 SmallVector<const Expr *, 2> CommaLHSs;
393 SmallVector<SubobjectAdjustment, 2> Adjustments;
394 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
396 for (const auto &Ignored : CommaLHSs)
397 EmitIgnoredExpr(Ignored);
399 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) {
400 if (opaque->getType()->isRecordType()) {
401 assert(Adjustments.empty());
402 return EmitOpaqueValueLValue(opaque);
406 // Create and initialize the reference temporary.
407 Address Object = createReferenceTemporary(*this, M, E);
408 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
409 Object = Address(llvm::ConstantExpr::getBitCast(
410 Var, ConvertTypeForMem(E->getType())->getPointerTo()),
411 Object.getAlignment());
412 // If the temporary is a global and has a constant initializer or is a
413 // constant temporary that we promoted to a global, we may have already
415 if (!Var->hasInitializer()) {
416 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
417 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
420 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
422 pushTemporaryCleanup(*this, M, E, Object);
424 // Perform derived-to-base casts and/or field accesses, to get from the
425 // temporary object we created (and, potentially, for which we extended
426 // the lifetime) to the subobject we're binding the reference to.
427 for (unsigned I = Adjustments.size(); I != 0; --I) {
428 SubobjectAdjustment &Adjustment = Adjustments[I-1];
429 switch (Adjustment.Kind) {
430 case SubobjectAdjustment::DerivedToBaseAdjustment:
432 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass,
433 Adjustment.DerivedToBase.BasePath->path_begin(),
434 Adjustment.DerivedToBase.BasePath->path_end(),
435 /*NullCheckValue=*/ false, E->getExprLoc());
438 case SubobjectAdjustment::FieldAdjustment: {
439 LValue LV = MakeAddrLValue(Object, E->getType(),
440 AlignmentSource::Decl);
441 LV = EmitLValueForField(LV, Adjustment.Field);
442 assert(LV.isSimple() &&
443 "materialized temporary field is not a simple lvalue");
444 Object = LV.getAddress();
448 case SubobjectAdjustment::MemberPointerAdjustment: {
449 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS);
450 Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr,
457 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl);
461 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) {
462 // Emit the expression as an lvalue.
463 LValue LV = EmitLValue(E);
464 assert(LV.isSimple());
465 llvm::Value *Value = LV.getPointer();
467 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) {
468 // C++11 [dcl.ref]p5 (as amended by core issue 453):
469 // If a glvalue to which a reference is directly bound designates neither
470 // an existing object or function of an appropriate type nor a region of
471 // storage of suitable size and alignment to contain an object of the
472 // reference's type, the behavior is undefined.
473 QualType Ty = E->getType();
474 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty);
477 return RValue::get(Value);
481 /// getAccessedFieldNo - Given an encoded value and a result number, return the
482 /// input field number being accessed.
483 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
484 const llvm::Constant *Elts) {
485 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx))
489 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h.
490 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low,
492 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL);
493 llvm::Value *K47 = Builder.getInt64(47);
494 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul);
495 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0);
496 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul);
497 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0);
498 return Builder.CreateMul(B1, KMul);
501 bool CodeGenFunction::sanitizePerformTypeCheck() const {
502 return SanOpts.has(SanitizerKind::Null) |
503 SanOpts.has(SanitizerKind::Alignment) |
504 SanOpts.has(SanitizerKind::ObjectSize) |
505 SanOpts.has(SanitizerKind::Vptr);
508 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
509 llvm::Value *Ptr, QualType Ty,
510 CharUnits Alignment, bool SkipNullCheck) {
511 if (!sanitizePerformTypeCheck())
514 // Don't check pointers outside the default address space. The null check
515 // isn't correct, the object-size check isn't supported by LLVM, and we can't
516 // communicate the addresses to the runtime handler for the vptr check.
517 if (Ptr->getType()->getPointerAddressSpace())
520 SanitizerScope SanScope(this);
522 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks;
523 llvm::BasicBlock *Done = nullptr;
525 bool AllowNullPointers = TCK == TCK_DowncastPointer || TCK == TCK_Upcast ||
526 TCK == TCK_UpcastToVirtualBase;
527 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) &&
529 // The glvalue must not be an empty glvalue.
530 llvm::Value *IsNonNull = Builder.CreateIsNotNull(Ptr);
532 if (AllowNullPointers) {
533 // When performing pointer casts, it's OK if the value is null.
534 // Skip the remaining checks in that case.
535 Done = createBasicBlock("null");
536 llvm::BasicBlock *Rest = createBasicBlock("not.null");
537 Builder.CreateCondBr(IsNonNull, Rest, Done);
540 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null));
544 if (SanOpts.has(SanitizerKind::ObjectSize) && !Ty->isIncompleteType()) {
545 uint64_t Size = getContext().getTypeSizeInChars(Ty).getQuantity();
547 // The glvalue must refer to a large enough storage region.
548 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
550 // FIXME: Get object address space
551 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
552 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
553 llvm::Value *Min = Builder.getFalse();
554 llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy);
555 llvm::Value *LargeEnough =
556 Builder.CreateICmpUGE(Builder.CreateCall(F, {CastAddr, Min}),
557 llvm::ConstantInt::get(IntPtrTy, Size));
558 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
561 uint64_t AlignVal = 0;
563 if (SanOpts.has(SanitizerKind::Alignment)) {
564 AlignVal = Alignment.getQuantity();
565 if (!Ty->isIncompleteType() && !AlignVal)
566 AlignVal = getContext().getTypeAlignInChars(Ty).getQuantity();
568 // The glvalue must be suitably aligned.
571 Builder.CreateAnd(Builder.CreatePtrToInt(Ptr, IntPtrTy),
572 llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
573 llvm::Value *Aligned =
574 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
575 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment));
579 if (Checks.size() > 0) {
580 llvm::Constant *StaticData[] = {
581 EmitCheckSourceLocation(Loc),
582 EmitCheckTypeDescriptor(Ty),
583 llvm::ConstantInt::get(SizeTy, AlignVal),
584 llvm::ConstantInt::get(Int8Ty, TCK)
586 EmitCheck(Checks, "type_mismatch", StaticData, Ptr);
589 // If possible, check that the vptr indicates that there is a subobject of
590 // type Ty at offset zero within this object.
592 // C++11 [basic.life]p5,6:
593 // [For storage which does not refer to an object within its lifetime]
594 // The program has undefined behavior if:
595 // -- the [pointer or glvalue] is used to access a non-static data member
596 // or call a non-static member function
597 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
598 if (SanOpts.has(SanitizerKind::Vptr) &&
599 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall ||
600 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference ||
601 TCK == TCK_UpcastToVirtualBase) &&
602 RD && RD->hasDefinition() && RD->isDynamicClass()) {
603 // Compute a hash of the mangled name of the type.
605 // FIXME: This is not guaranteed to be deterministic! Move to a
606 // fingerprinting mechanism once LLVM provides one. For the time
607 // being the implementation happens to be deterministic.
608 SmallString<64> MangledName;
609 llvm::raw_svector_ostream Out(MangledName);
610 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
613 // Blacklist based on the mangled type.
614 if (!CGM.getContext().getSanitizerBlacklist().isBlacklistedType(
616 llvm::hash_code TypeHash = hash_value(Out.str());
618 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
619 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
620 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
621 Address VPtrAddr(Builder.CreateBitCast(Ptr, VPtrTy), getPointerAlign());
622 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
623 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
625 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
626 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
628 // Look the hash up in our cache.
629 const int CacheSize = 128;
630 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
631 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
632 "__ubsan_vptr_type_cache");
633 llvm::Value *Slot = Builder.CreateAnd(Hash,
634 llvm::ConstantInt::get(IntPtrTy,
636 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
637 llvm::Value *CacheVal =
638 Builder.CreateAlignedLoad(Builder.CreateInBoundsGEP(Cache, Indices),
641 // If the hash isn't in the cache, call a runtime handler to perform the
642 // hard work of checking whether the vptr is for an object of the right
643 // type. This will either fill in the cache and return, or produce a
645 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash);
646 llvm::Constant *StaticData[] = {
647 EmitCheckSourceLocation(Loc),
648 EmitCheckTypeDescriptor(Ty),
649 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
650 llvm::ConstantInt::get(Int8Ty, TCK)
652 llvm::Value *DynamicData[] = { Ptr, Hash };
653 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr),
654 "dynamic_type_cache_miss", StaticData, DynamicData);
659 Builder.CreateBr(Done);
664 /// Determine whether this expression refers to a flexible array member in a
665 /// struct. We disable array bounds checks for such members.
666 static bool isFlexibleArrayMemberExpr(const Expr *E) {
667 // For compatibility with existing code, we treat arrays of length 0 or
668 // 1 as flexible array members.
669 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
670 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
671 if (CAT->getSize().ugt(1))
673 } else if (!isa<IncompleteArrayType>(AT))
676 E = E->IgnoreParens();
678 // A flexible array member must be the last member in the class.
679 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
680 // FIXME: If the base type of the member expr is not FD->getParent(),
681 // this should not be treated as a flexible array member access.
682 if (const auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
683 RecordDecl::field_iterator FI(
684 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
685 return ++FI == FD->getParent()->field_end();
692 /// If Base is known to point to the start of an array, return the length of
693 /// that array. Return 0 if the length cannot be determined.
694 static llvm::Value *getArrayIndexingBound(
695 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
696 // For the vector indexing extension, the bound is the number of elements.
697 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
698 IndexedType = Base->getType();
699 return CGF.Builder.getInt32(VT->getNumElements());
702 Base = Base->IgnoreParens();
704 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
705 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
706 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
707 IndexedType = CE->getSubExpr()->getType();
708 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
709 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
710 return CGF.Builder.getInt(CAT->getSize());
711 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
712 return CGF.getVLASize(VAT).first;
719 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
720 llvm::Value *Index, QualType IndexType,
722 assert(SanOpts.has(SanitizerKind::ArrayBounds) &&
723 "should not be called unless adding bounds checks");
724 SanitizerScope SanScope(this);
726 QualType IndexedType;
727 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
731 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
732 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
733 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
735 llvm::Constant *StaticData[] = {
736 EmitCheckSourceLocation(E->getExprLoc()),
737 EmitCheckTypeDescriptor(IndexedType),
738 EmitCheckTypeDescriptor(IndexType)
740 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
741 : Builder.CreateICmpULE(IndexVal, BoundVal);
742 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds), "out_of_bounds",
747 CodeGenFunction::ComplexPairTy CodeGenFunction::
748 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
749 bool isInc, bool isPre) {
750 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
752 llvm::Value *NextVal;
753 if (isa<llvm::IntegerType>(InVal.first->getType())) {
754 uint64_t AmountVal = isInc ? 1 : -1;
755 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
757 // Add the inc/dec to the real part.
758 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
760 QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
761 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
764 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
766 // Add the inc/dec to the real part.
767 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
770 ComplexPairTy IncVal(NextVal, InVal.second);
772 // Store the updated result through the lvalue.
773 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
775 // If this is a postinc, return the value read from memory, otherwise use the
777 return isPre ? IncVal : InVal;
780 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E,
781 CodeGenFunction *CGF) {
782 // Bind VLAs in the cast type.
783 if (CGF && E->getType()->isVariablyModifiedType())
784 CGF->EmitVariablyModifiedType(E->getType());
786 if (CGDebugInfo *DI = getModuleDebugInfo())
787 DI->EmitExplicitCastType(E->getType());
790 //===----------------------------------------------------------------------===//
791 // LValue Expression Emission
792 //===----------------------------------------------------------------------===//
794 /// EmitPointerWithAlignment - Given an expression of pointer type, try to
795 /// derive a more accurate bound on the alignment of the pointer.
796 Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
797 AlignmentSource *Source) {
798 // We allow this with ObjC object pointers because of fragile ABIs.
799 assert(E->getType()->isPointerType() ||
800 E->getType()->isObjCObjectPointerType());
801 E = E->IgnoreParens();
804 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
805 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE))
806 CGM.EmitExplicitCastExprType(ECE, this);
808 switch (CE->getCastKind()) {
809 // Non-converting casts (but not C's implicit conversion from void*).
812 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) {
813 if (PtrTy->getPointeeType()->isVoidType())
816 AlignmentSource InnerSource;
817 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), &InnerSource);
818 if (Source) *Source = InnerSource;
820 // If this is an explicit bitcast, and the source l-value is
821 // opaque, honor the alignment of the casted-to type.
822 if (isa<ExplicitCastExpr>(CE) &&
823 InnerSource != AlignmentSource::Decl) {
824 Addr = Address(Addr.getPointer(),
825 getNaturalPointeeTypeAlignment(E->getType(), Source));
828 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast) &&
829 CE->getCastKind() == CK_BitCast) {
830 if (auto PT = E->getType()->getAs<PointerType>())
831 EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr.getPointer(),
833 CodeGenFunction::CFITCK_UnrelatedCast,
837 return Builder.CreateBitCast(Addr, ConvertType(E->getType()));
841 // Array-to-pointer decay.
842 case CK_ArrayToPointerDecay:
843 return EmitArrayToPointerDecay(CE->getSubExpr(), Source);
845 // Derived-to-base conversions.
846 case CK_UncheckedDerivedToBase:
847 case CK_DerivedToBase: {
848 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), Source);
849 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl();
850 return GetAddressOfBaseClass(Addr, Derived,
851 CE->path_begin(), CE->path_end(),
852 ShouldNullCheckClassCastValue(CE),
856 // TODO: Is there any reason to treat base-to-derived conversions
864 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
865 if (UO->getOpcode() == UO_AddrOf) {
866 LValue LV = EmitLValue(UO->getSubExpr());
867 if (Source) *Source = LV.getAlignmentSource();
868 return LV.getAddress();
872 // TODO: conditional operators, comma.
874 // Otherwise, use the alignment of the type.
875 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(), Source);
876 return Address(EmitScalarExpr(E), Align);
879 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
880 if (Ty->isVoidType())
881 return RValue::get(nullptr);
883 switch (getEvaluationKind(Ty)) {
886 ConvertType(Ty->castAs<ComplexType>()->getElementType());
887 llvm::Value *U = llvm::UndefValue::get(EltTy);
888 return RValue::getComplex(std::make_pair(U, U));
891 // If this is a use of an undefined aggregate type, the aggregate must have an
892 // identifiable address. Just because the contents of the value are undefined
893 // doesn't mean that the address can't be taken and compared.
894 case TEK_Aggregate: {
895 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
896 return RValue::getAggregate(DestPtr);
900 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
902 llvm_unreachable("bad evaluation kind");
905 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
907 ErrorUnsupported(E, Name);
908 return GetUndefRValue(E->getType());
911 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
913 ErrorUnsupported(E, Name);
914 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
915 return MakeAddrLValue(Address(llvm::UndefValue::get(Ty), CharUnits::One()),
919 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
921 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E))
922 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
925 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple())
926 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(),
927 E->getType(), LV.getAlignment());
931 /// EmitLValue - Emit code to compute a designator that specifies the location
932 /// of the expression.
934 /// This can return one of two things: a simple address or a bitfield reference.
935 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
936 /// an LLVM pointer type.
938 /// If this returns a bitfield reference, nothing about the pointee type of the
939 /// LLVM value is known: For example, it may not be a pointer to an integer.
941 /// If this returns a normal address, and if the lvalue's C type is fixed size,
942 /// this method guarantees that the returned pointer type will point to an LLVM
943 /// type of the same size of the lvalue's type. If the lvalue has a variable
944 /// length type, this is not possible.
946 LValue CodeGenFunction::EmitLValue(const Expr *E) {
947 ApplyDebugLocation DL(*this, E);
948 switch (E->getStmtClass()) {
949 default: return EmitUnsupportedLValue(E, "l-value expression");
951 case Expr::ObjCPropertyRefExprClass:
952 llvm_unreachable("cannot emit a property reference directly");
954 case Expr::ObjCSelectorExprClass:
955 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
956 case Expr::ObjCIsaExprClass:
957 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
958 case Expr::BinaryOperatorClass:
959 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
960 case Expr::CompoundAssignOperatorClass: {
961 QualType Ty = E->getType();
962 if (const AtomicType *AT = Ty->getAs<AtomicType>())
963 Ty = AT->getValueType();
964 if (!Ty->isAnyComplexType())
965 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
966 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
968 case Expr::CallExprClass:
969 case Expr::CXXMemberCallExprClass:
970 case Expr::CXXOperatorCallExprClass:
971 case Expr::UserDefinedLiteralClass:
972 return EmitCallExprLValue(cast<CallExpr>(E));
973 case Expr::VAArgExprClass:
974 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
975 case Expr::DeclRefExprClass:
976 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
977 case Expr::ParenExprClass:
978 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
979 case Expr::GenericSelectionExprClass:
980 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
981 case Expr::PredefinedExprClass:
982 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
983 case Expr::StringLiteralClass:
984 return EmitStringLiteralLValue(cast<StringLiteral>(E));
985 case Expr::ObjCEncodeExprClass:
986 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
987 case Expr::PseudoObjectExprClass:
988 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
989 case Expr::InitListExprClass:
990 return EmitInitListLValue(cast<InitListExpr>(E));
991 case Expr::CXXTemporaryObjectExprClass:
992 case Expr::CXXConstructExprClass:
993 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
994 case Expr::CXXBindTemporaryExprClass:
995 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
996 case Expr::CXXUuidofExprClass:
997 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
998 case Expr::LambdaExprClass:
999 return EmitLambdaLValue(cast<LambdaExpr>(E));
1001 case Expr::ExprWithCleanupsClass: {
1002 const auto *cleanups = cast<ExprWithCleanups>(E);
1003 enterFullExpression(cleanups);
1004 RunCleanupsScope Scope(*this);
1005 return EmitLValue(cleanups->getSubExpr());
1008 case Expr::CXXDefaultArgExprClass:
1009 return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
1010 case Expr::CXXDefaultInitExprClass: {
1011 CXXDefaultInitExprScope Scope(*this);
1012 return EmitLValue(cast<CXXDefaultInitExpr>(E)->getExpr());
1014 case Expr::CXXTypeidExprClass:
1015 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
1017 case Expr::ObjCMessageExprClass:
1018 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
1019 case Expr::ObjCIvarRefExprClass:
1020 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
1021 case Expr::StmtExprClass:
1022 return EmitStmtExprLValue(cast<StmtExpr>(E));
1023 case Expr::UnaryOperatorClass:
1024 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
1025 case Expr::ArraySubscriptExprClass:
1026 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
1027 case Expr::OMPArraySectionExprClass:
1028 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E));
1029 case Expr::ExtVectorElementExprClass:
1030 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
1031 case Expr::MemberExprClass:
1032 return EmitMemberExpr(cast<MemberExpr>(E));
1033 case Expr::CompoundLiteralExprClass:
1034 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
1035 case Expr::ConditionalOperatorClass:
1036 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
1037 case Expr::BinaryConditionalOperatorClass:
1038 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
1039 case Expr::ChooseExprClass:
1040 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
1041 case Expr::OpaqueValueExprClass:
1042 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
1043 case Expr::SubstNonTypeTemplateParmExprClass:
1044 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
1045 case Expr::ImplicitCastExprClass:
1046 case Expr::CStyleCastExprClass:
1047 case Expr::CXXFunctionalCastExprClass:
1048 case Expr::CXXStaticCastExprClass:
1049 case Expr::CXXDynamicCastExprClass:
1050 case Expr::CXXReinterpretCastExprClass:
1051 case Expr::CXXConstCastExprClass:
1052 case Expr::ObjCBridgedCastExprClass:
1053 return EmitCastLValue(cast<CastExpr>(E));
1055 case Expr::MaterializeTemporaryExprClass:
1056 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
1060 /// Given an object of the given canonical type, can we safely copy a
1061 /// value out of it based on its initializer?
1062 static bool isConstantEmittableObjectType(QualType type) {
1063 assert(type.isCanonical());
1064 assert(!type->isReferenceType());
1066 // Must be const-qualified but non-volatile.
1067 Qualifiers qs = type.getLocalQualifiers();
1068 if (!qs.hasConst() || qs.hasVolatile()) return false;
1070 // Otherwise, all object types satisfy this except C++ classes with
1071 // mutable subobjects or non-trivial copy/destroy behavior.
1072 if (const auto *RT = dyn_cast<RecordType>(type))
1073 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1074 if (RD->hasMutableFields() || !RD->isTrivial())
1080 /// Can we constant-emit a load of a reference to a variable of the
1081 /// given type? This is different from predicates like
1082 /// Decl::isUsableInConstantExpressions because we do want it to apply
1083 /// in situations that don't necessarily satisfy the language's rules
1084 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
1085 /// to do this with const float variables even if those variables
1086 /// aren't marked 'constexpr'.
1087 enum ConstantEmissionKind {
1089 CEK_AsReferenceOnly,
1090 CEK_AsValueOrReference,
1093 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
1094 type = type.getCanonicalType();
1095 if (const auto *ref = dyn_cast<ReferenceType>(type)) {
1096 if (isConstantEmittableObjectType(ref->getPointeeType()))
1097 return CEK_AsValueOrReference;
1098 return CEK_AsReferenceOnly;
1100 if (isConstantEmittableObjectType(type))
1101 return CEK_AsValueOnly;
1105 /// Try to emit a reference to the given value without producing it as
1106 /// an l-value. This is actually more than an optimization: we can't
1107 /// produce an l-value for variables that we never actually captured
1108 /// in a block or lambda, which means const int variables or constexpr
1109 /// literals or similar.
1110 CodeGenFunction::ConstantEmission
1111 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
1112 ValueDecl *value = refExpr->getDecl();
1114 // The value needs to be an enum constant or a constant variable.
1115 ConstantEmissionKind CEK;
1116 if (isa<ParmVarDecl>(value)) {
1118 } else if (auto *var = dyn_cast<VarDecl>(value)) {
1119 CEK = checkVarTypeForConstantEmission(var->getType());
1120 } else if (isa<EnumConstantDecl>(value)) {
1121 CEK = CEK_AsValueOnly;
1125 if (CEK == CEK_None) return ConstantEmission();
1127 Expr::EvalResult result;
1128 bool resultIsReference;
1129 QualType resultType;
1131 // It's best to evaluate all the way as an r-value if that's permitted.
1132 if (CEK != CEK_AsReferenceOnly &&
1133 refExpr->EvaluateAsRValue(result, getContext())) {
1134 resultIsReference = false;
1135 resultType = refExpr->getType();
1137 // Otherwise, try to evaluate as an l-value.
1138 } else if (CEK != CEK_AsValueOnly &&
1139 refExpr->EvaluateAsLValue(result, getContext())) {
1140 resultIsReference = true;
1141 resultType = value->getType();
1145 return ConstantEmission();
1148 // In any case, if the initializer has side-effects, abandon ship.
1149 if (result.HasSideEffects)
1150 return ConstantEmission();
1152 // Emit as a constant.
1153 llvm::Constant *C = CGM.EmitConstantValue(result.Val, resultType, this);
1155 // Make sure we emit a debug reference to the global variable.
1156 // This should probably fire even for
1157 if (isa<VarDecl>(value)) {
1158 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
1159 EmitDeclRefExprDbgValue(refExpr, C);
1161 assert(isa<EnumConstantDecl>(value));
1162 EmitDeclRefExprDbgValue(refExpr, C);
1165 // If we emitted a reference constant, we need to dereference that.
1166 if (resultIsReference)
1167 return ConstantEmission::forReference(C);
1169 return ConstantEmission::forValue(C);
1172 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1173 SourceLocation Loc) {
1174 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
1175 lvalue.getType(), Loc, lvalue.getAlignmentSource(),
1176 lvalue.getTBAAInfo(),
1177 lvalue.getTBAABaseType(), lvalue.getTBAAOffset(),
1178 lvalue.isNontemporal());
1181 static bool hasBooleanRepresentation(QualType Ty) {
1182 if (Ty->isBooleanType())
1185 if (const EnumType *ET = Ty->getAs<EnumType>())
1186 return ET->getDecl()->getIntegerType()->isBooleanType();
1188 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1189 return hasBooleanRepresentation(AT->getValueType());
1194 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1195 llvm::APInt &Min, llvm::APInt &End,
1197 const EnumType *ET = Ty->getAs<EnumType>();
1198 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1199 ET && !ET->getDecl()->isFixed();
1200 bool IsBool = hasBooleanRepresentation(Ty);
1201 if (!IsBool && !IsRegularCPlusPlusEnum)
1205 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1206 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1208 const EnumDecl *ED = ET->getDecl();
1209 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1210 unsigned Bitwidth = LTy->getScalarSizeInBits();
1211 unsigned NumNegativeBits = ED->getNumNegativeBits();
1212 unsigned NumPositiveBits = ED->getNumPositiveBits();
1214 if (NumNegativeBits) {
1215 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1216 assert(NumBits <= Bitwidth);
1217 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1220 assert(NumPositiveBits <= Bitwidth);
1221 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1222 Min = llvm::APInt(Bitwidth, 0);
1228 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1229 llvm::APInt Min, End;
1230 if (!getRangeForType(*this, Ty, Min, End,
1231 CGM.getCodeGenOpts().StrictEnums))
1234 llvm::MDBuilder MDHelper(getLLVMContext());
1235 return MDHelper.createRange(Min, End);
1238 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
1241 AlignmentSource AlignSource,
1242 llvm::MDNode *TBAAInfo,
1243 QualType TBAABaseType,
1244 uint64_t TBAAOffset,
1245 bool isNontemporal) {
1246 // For better performance, handle vector loads differently.
1247 if (Ty->isVectorType()) {
1248 const llvm::Type *EltTy = Addr.getElementType();
1250 const auto *VTy = cast<llvm::VectorType>(EltTy);
1252 // Handle vectors of size 3 like size 4 for better performance.
1253 if (VTy->getNumElements() == 3) {
1255 // Bitcast to vec4 type.
1256 llvm::VectorType *vec4Ty = llvm::VectorType::get(VTy->getElementType(),
1258 Address Cast = Builder.CreateElementBitCast(Addr, vec4Ty, "castToVec4");
1260 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1262 // Shuffle vector to get vec3.
1263 V = Builder.CreateShuffleVector(V, llvm::UndefValue::get(vec4Ty),
1264 {0, 1, 2}, "extractVec");
1265 return EmitFromMemory(V, Ty);
1269 // Atomic operations have to be done on integral types.
1270 if (Ty->isAtomicType() || typeIsSuitableForInlineAtomic(Ty, Volatile)) {
1272 LValue::MakeAddr(Addr, Ty, getContext(), AlignSource, TBAAInfo);
1273 return EmitAtomicLoad(lvalue, Loc).getScalarVal();
1276 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
1277 if (isNontemporal) {
1278 llvm::MDNode *Node = llvm::MDNode::get(
1279 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1280 Load->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1283 llvm::MDNode *TBAAPath = CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo,
1286 CGM.DecorateInstructionWithTBAA(Load, TBAAPath,
1287 false /*ConvertTypeToTag*/);
1290 bool NeedsBoolCheck =
1291 SanOpts.has(SanitizerKind::Bool) && hasBooleanRepresentation(Ty);
1292 bool NeedsEnumCheck =
1293 SanOpts.has(SanitizerKind::Enum) && Ty->getAs<EnumType>();
1294 if (NeedsBoolCheck || NeedsEnumCheck) {
1295 SanitizerScope SanScope(this);
1296 llvm::APInt Min, End;
1297 if (getRangeForType(*this, Ty, Min, End, true)) {
1301 Check = Builder.CreateICmpULE(
1302 Load, llvm::ConstantInt::get(getLLVMContext(), End));
1304 llvm::Value *Upper = Builder.CreateICmpSLE(
1305 Load, llvm::ConstantInt::get(getLLVMContext(), End));
1306 llvm::Value *Lower = Builder.CreateICmpSGE(
1307 Load, llvm::ConstantInt::get(getLLVMContext(), Min));
1308 Check = Builder.CreateAnd(Upper, Lower);
1310 llvm::Constant *StaticArgs[] = {
1311 EmitCheckSourceLocation(Loc),
1312 EmitCheckTypeDescriptor(Ty)
1314 SanitizerMask Kind = NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
1315 EmitCheck(std::make_pair(Check, Kind), "load_invalid_value", StaticArgs,
1316 EmitCheckValue(Load));
1318 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1319 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1320 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1322 return EmitFromMemory(Load, Ty);
1325 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1326 // Bool has a different representation in memory than in registers.
1327 if (hasBooleanRepresentation(Ty)) {
1328 // This should really always be an i1, but sometimes it's already
1329 // an i8, and it's awkward to track those cases down.
1330 if (Value->getType()->isIntegerTy(1))
1331 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1332 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1333 "wrong value rep of bool");
1339 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1340 // Bool has a different representation in memory than in registers.
1341 if (hasBooleanRepresentation(Ty)) {
1342 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1343 "wrong value rep of bool");
1344 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1350 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
1351 bool Volatile, QualType Ty,
1352 AlignmentSource AlignSource,
1353 llvm::MDNode *TBAAInfo,
1354 bool isInit, QualType TBAABaseType,
1355 uint64_t TBAAOffset,
1356 bool isNontemporal) {
1358 // Handle vectors differently to get better performance.
1359 if (Ty->isVectorType()) {
1360 llvm::Type *SrcTy = Value->getType();
1361 auto *VecTy = cast<llvm::VectorType>(SrcTy);
1362 // Handle vec3 special.
1363 if (VecTy->getNumElements() == 3) {
1364 // Our source is a vec3, do a shuffle vector to make it a vec4.
1365 llvm::Constant *Mask[] = {Builder.getInt32(0), Builder.getInt32(1),
1366 Builder.getInt32(2),
1367 llvm::UndefValue::get(Builder.getInt32Ty())};
1368 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1369 Value = Builder.CreateShuffleVector(Value,
1370 llvm::UndefValue::get(VecTy),
1371 MaskV, "extractVec");
1372 SrcTy = llvm::VectorType::get(VecTy->getElementType(), 4);
1374 if (Addr.getElementType() != SrcTy) {
1375 Addr = Builder.CreateElementBitCast(Addr, SrcTy, "storetmp");
1379 Value = EmitToMemory(Value, Ty);
1381 if (Ty->isAtomicType() ||
1382 (!isInit && typeIsSuitableForInlineAtomic(Ty, Volatile))) {
1383 EmitAtomicStore(RValue::get(Value),
1384 LValue::MakeAddr(Addr, Ty, getContext(),
1385 AlignSource, TBAAInfo),
1390 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1391 if (isNontemporal) {
1392 llvm::MDNode *Node =
1393 llvm::MDNode::get(Store->getContext(),
1394 llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1395 Store->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1398 llvm::MDNode *TBAAPath = CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo,
1401 CGM.DecorateInstructionWithTBAA(Store, TBAAPath,
1402 false /*ConvertTypeToTag*/);
1406 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1408 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
1409 lvalue.getType(), lvalue.getAlignmentSource(),
1410 lvalue.getTBAAInfo(), isInit, lvalue.getTBAABaseType(),
1411 lvalue.getTBAAOffset(), lvalue.isNontemporal());
1414 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1415 /// method emits the address of the lvalue, then loads the result as an rvalue,
1416 /// returning the rvalue.
1417 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1418 if (LV.isObjCWeak()) {
1419 // load of a __weak object.
1420 Address AddrWeakObj = LV.getAddress();
1421 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1424 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1425 // In MRC mode, we do a load+autorelease.
1426 if (!getLangOpts().ObjCAutoRefCount) {
1427 return RValue::get(EmitARCLoadWeak(LV.getAddress()));
1430 // In ARC mode, we load retained and then consume the value.
1431 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
1432 Object = EmitObjCConsumeObject(LV.getType(), Object);
1433 return RValue::get(Object);
1436 if (LV.isSimple()) {
1437 assert(!LV.getType()->isFunctionType());
1439 // Everything needs a load.
1440 return RValue::get(EmitLoadOfScalar(LV, Loc));
1443 if (LV.isVectorElt()) {
1444 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(),
1445 LV.isVolatileQualified());
1446 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1450 // If this is a reference to a subset of the elements of a vector, either
1451 // shuffle the input or extract/insert them as appropriate.
1452 if (LV.isExtVectorElt())
1453 return EmitLoadOfExtVectorElementLValue(LV);
1455 // Global Register variables always invoke intrinsics
1456 if (LV.isGlobalReg())
1457 return EmitLoadOfGlobalRegLValue(LV);
1459 assert(LV.isBitField() && "Unknown LValue type!");
1460 return EmitLoadOfBitfieldLValue(LV);
1463 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV) {
1464 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1466 // Get the output type.
1467 llvm::Type *ResLTy = ConvertType(LV.getType());
1469 Address Ptr = LV.getBitFieldAddress();
1470 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load");
1472 if (Info.IsSigned) {
1473 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1474 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1476 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1477 if (Info.Offset + HighBits)
1478 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1481 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1482 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1483 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1487 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1489 return RValue::get(Val);
1492 // If this is a reference to a subset of the elements of a vector, create an
1493 // appropriate shufflevector.
1494 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1495 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(),
1496 LV.isVolatileQualified());
1498 const llvm::Constant *Elts = LV.getExtVectorElts();
1500 // If the result of the expression is a non-vector type, we must be extracting
1501 // a single element. Just codegen as an extractelement.
1502 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1504 unsigned InIdx = getAccessedFieldNo(0, Elts);
1505 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1506 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1509 // Always use shuffle vector to try to retain the original program structure
1510 unsigned NumResultElts = ExprVT->getNumElements();
1512 SmallVector<llvm::Constant*, 4> Mask;
1513 for (unsigned i = 0; i != NumResultElts; ++i)
1514 Mask.push_back(Builder.getInt32(getAccessedFieldNo(i, Elts)));
1516 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1517 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1519 return RValue::get(Vec);
1522 /// @brief Generates lvalue for partial ext_vector access.
1523 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) {
1524 Address VectorAddress = LV.getExtVectorAddress();
1525 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1526 QualType EQT = ExprVT->getElementType();
1527 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT);
1529 Address CastToPointerElement =
1530 Builder.CreateElementBitCast(VectorAddress, VectorElementTy,
1531 "conv.ptr.element");
1533 const llvm::Constant *Elts = LV.getExtVectorElts();
1534 unsigned ix = getAccessedFieldNo(0, Elts);
1536 Address VectorBasePtrPlusIx =
1537 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix,
1538 getContext().getTypeSizeInChars(EQT),
1541 return VectorBasePtrPlusIx;
1544 /// @brief Load of global gamed gegisters are always calls to intrinsics.
1545 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
1546 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
1547 "Bad type for register variable");
1548 llvm::MDNode *RegName = cast<llvm::MDNode>(
1549 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata());
1551 // We accept integer and pointer types only
1552 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
1553 llvm::Type *Ty = OrigTy;
1554 if (OrigTy->isPointerTy())
1555 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1556 llvm::Type *Types[] = { Ty };
1558 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
1559 llvm::Value *Call = Builder.CreateCall(
1560 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName));
1561 if (OrigTy->isPointerTy())
1562 Call = Builder.CreateIntToPtr(Call, OrigTy);
1563 return RValue::get(Call);
1567 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
1568 /// lvalue, where both are guaranteed to the have the same type, and that type
1570 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
1572 if (!Dst.isSimple()) {
1573 if (Dst.isVectorElt()) {
1574 // Read/modify/write the vector, inserting the new element.
1575 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(),
1576 Dst.isVolatileQualified());
1577 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
1578 Dst.getVectorIdx(), "vecins");
1579 Builder.CreateStore(Vec, Dst.getVectorAddress(),
1580 Dst.isVolatileQualified());
1584 // If this is an update of extended vector elements, insert them as
1586 if (Dst.isExtVectorElt())
1587 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
1589 if (Dst.isGlobalReg())
1590 return EmitStoreThroughGlobalRegLValue(Src, Dst);
1592 assert(Dst.isBitField() && "Unknown LValue type");
1593 return EmitStoreThroughBitfieldLValue(Src, Dst);
1596 // There's special magic for assigning into an ARC-qualified l-value.
1597 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
1599 case Qualifiers::OCL_None:
1600 llvm_unreachable("present but none");
1602 case Qualifiers::OCL_ExplicitNone:
1606 case Qualifiers::OCL_Strong:
1607 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
1610 case Qualifiers::OCL_Weak:
1611 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true);
1614 case Qualifiers::OCL_Autoreleasing:
1615 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
1616 Src.getScalarVal()));
1617 // fall into the normal path
1622 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
1623 // load of a __weak object.
1624 Address LvalueDst = Dst.getAddress();
1625 llvm::Value *src = Src.getScalarVal();
1626 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
1630 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
1631 // load of a __strong object.
1632 Address LvalueDst = Dst.getAddress();
1633 llvm::Value *src = Src.getScalarVal();
1634 if (Dst.isObjCIvar()) {
1635 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
1636 llvm::Type *ResultType = IntPtrTy;
1637 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp());
1638 llvm::Value *RHS = dst.getPointer();
1639 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
1641 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType,
1642 "sub.ptr.lhs.cast");
1643 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
1644 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
1646 } else if (Dst.isGlobalObjCRef()) {
1647 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
1648 Dst.isThreadLocalRef());
1651 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
1655 assert(Src.isScalar() && "Can't emit an agg store with this method");
1656 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
1659 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
1660 llvm::Value **Result) {
1661 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
1662 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
1663 Address Ptr = Dst.getBitFieldAddress();
1665 // Get the source value, truncated to the width of the bit-field.
1666 llvm::Value *SrcVal = Src.getScalarVal();
1668 // Cast the source to the storage type and shift it into place.
1669 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(),
1670 /*IsSigned=*/false);
1671 llvm::Value *MaskedVal = SrcVal;
1673 // See if there are other bits in the bitfield's storage we'll need to load
1674 // and mask together with source before storing.
1675 if (Info.StorageSize != Info.Size) {
1676 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
1678 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load");
1680 // Mask the source value as needed.
1681 if (!hasBooleanRepresentation(Dst.getType()))
1682 SrcVal = Builder.CreateAnd(SrcVal,
1683 llvm::APInt::getLowBitsSet(Info.StorageSize,
1688 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
1690 // Mask out the original value.
1691 Val = Builder.CreateAnd(Val,
1692 ~llvm::APInt::getBitsSet(Info.StorageSize,
1694 Info.Offset + Info.Size),
1697 // Or together the unchanged values and the source value.
1698 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
1700 assert(Info.Offset == 0);
1703 // Write the new value back out.
1704 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified());
1706 // Return the new value of the bit-field, if requested.
1708 llvm::Value *ResultVal = MaskedVal;
1710 // Sign extend the value if needed.
1711 if (Info.IsSigned) {
1712 assert(Info.Size <= Info.StorageSize);
1713 unsigned HighBits = Info.StorageSize - Info.Size;
1715 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
1716 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
1720 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
1722 *Result = EmitFromMemory(ResultVal, Dst.getType());
1726 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
1728 // This access turns into a read/modify/write of the vector. Load the input
1730 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddress(),
1731 Dst.isVolatileQualified());
1732 const llvm::Constant *Elts = Dst.getExtVectorElts();
1734 llvm::Value *SrcVal = Src.getScalarVal();
1736 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
1737 unsigned NumSrcElts = VTy->getNumElements();
1738 unsigned NumDstElts =
1739 cast<llvm::VectorType>(Vec->getType())->getNumElements();
1740 if (NumDstElts == NumSrcElts) {
1741 // Use shuffle vector is the src and destination are the same number of
1742 // elements and restore the vector mask since it is on the side it will be
1744 SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
1745 for (unsigned i = 0; i != NumSrcElts; ++i)
1746 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i);
1748 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1749 Vec = Builder.CreateShuffleVector(SrcVal,
1750 llvm::UndefValue::get(Vec->getType()),
1752 } else if (NumDstElts > NumSrcElts) {
1753 // Extended the source vector to the same length and then shuffle it
1754 // into the destination.
1755 // FIXME: since we're shuffling with undef, can we just use the indices
1756 // into that? This could be simpler.
1757 SmallVector<llvm::Constant*, 4> ExtMask;
1758 for (unsigned i = 0; i != NumSrcElts; ++i)
1759 ExtMask.push_back(Builder.getInt32(i));
1760 ExtMask.resize(NumDstElts, llvm::UndefValue::get(Int32Ty));
1761 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
1762 llvm::Value *ExtSrcVal =
1763 Builder.CreateShuffleVector(SrcVal,
1764 llvm::UndefValue::get(SrcVal->getType()),
1767 SmallVector<llvm::Constant*, 4> Mask;
1768 for (unsigned i = 0; i != NumDstElts; ++i)
1769 Mask.push_back(Builder.getInt32(i));
1771 // When the vector size is odd and .odd or .hi is used, the last element
1772 // of the Elts constant array will be one past the size of the vector.
1773 // Ignore the last element here, if it is greater than the mask size.
1774 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
1777 // modify when what gets shuffled in
1778 for (unsigned i = 0; i != NumSrcElts; ++i)
1779 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i+NumDstElts);
1780 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1781 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV);
1783 // We should never shorten the vector
1784 llvm_unreachable("unexpected shorten vector length");
1787 // If the Src is a scalar (not a vector) it must be updating one element.
1788 unsigned InIdx = getAccessedFieldNo(0, Elts);
1789 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1790 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
1793 Builder.CreateStore(Vec, Dst.getExtVectorAddress(),
1794 Dst.isVolatileQualified());
1797 /// @brief Store of global named registers are always calls to intrinsics.
1798 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
1799 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
1800 "Bad type for register variable");
1801 llvm::MDNode *RegName = cast<llvm::MDNode>(
1802 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata());
1803 assert(RegName && "Register LValue is not metadata");
1805 // We accept integer and pointer types only
1806 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
1807 llvm::Type *Ty = OrigTy;
1808 if (OrigTy->isPointerTy())
1809 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1810 llvm::Type *Types[] = { Ty };
1812 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
1813 llvm::Value *Value = Src.getScalarVal();
1814 if (OrigTy->isPointerTy())
1815 Value = Builder.CreatePtrToInt(Value, Ty);
1817 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value});
1820 // setObjCGCLValueClass - sets class of the lvalue for the purpose of
1821 // generating write-barries API. It is currently a global, ivar,
1823 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1825 bool IsMemberAccess=false) {
1826 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
1829 if (isa<ObjCIvarRefExpr>(E)) {
1830 QualType ExpTy = E->getType();
1831 if (IsMemberAccess && ExpTy->isPointerType()) {
1832 // If ivar is a structure pointer, assigning to field of
1833 // this struct follows gcc's behavior and makes it a non-ivar
1834 // writer-barrier conservatively.
1835 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1836 if (ExpTy->isRecordType()) {
1837 LV.setObjCIvar(false);
1841 LV.setObjCIvar(true);
1842 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
1843 LV.setBaseIvarExp(Exp->getBase());
1844 LV.setObjCArray(E->getType()->isArrayType());
1848 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
1849 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
1850 if (VD->hasGlobalStorage()) {
1851 LV.setGlobalObjCRef(true);
1852 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
1855 LV.setObjCArray(E->getType()->isArrayType());
1859 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
1860 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1864 if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
1865 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1866 if (LV.isObjCIvar()) {
1867 // If cast is to a structure pointer, follow gcc's behavior and make it
1868 // a non-ivar write-barrier.
1869 QualType ExpTy = E->getType();
1870 if (ExpTy->isPointerType())
1871 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1872 if (ExpTy->isRecordType())
1873 LV.setObjCIvar(false);
1878 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
1879 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
1883 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
1884 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1888 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
1889 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1893 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
1894 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1898 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
1899 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1900 if (LV.isObjCIvar() && !LV.isObjCArray())
1901 // Using array syntax to assigning to what an ivar points to is not
1902 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
1903 LV.setObjCIvar(false);
1904 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
1905 // Using array syntax to assigning to what global points to is not
1906 // same as assigning to the global itself. {id *G;} G[i] = 0;
1907 LV.setGlobalObjCRef(false);
1911 if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
1912 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
1913 // We don't know if member is an 'ivar', but this flag is looked at
1914 // only in the context of LV.isObjCIvar().
1915 LV.setObjCArray(E->getType()->isArrayType());
1920 static llvm::Value *
1921 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
1922 llvm::Value *V, llvm::Type *IRType,
1923 StringRef Name = StringRef()) {
1924 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
1925 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
1928 static LValue EmitThreadPrivateVarDeclLValue(
1929 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr,
1930 llvm::Type *RealVarTy, SourceLocation Loc) {
1931 Addr = CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc);
1932 Addr = CGF.Builder.CreateElementBitCast(Addr, RealVarTy);
1933 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
1936 Address CodeGenFunction::EmitLoadOfReference(Address Addr,
1937 const ReferenceType *RefTy,
1938 AlignmentSource *Source) {
1939 llvm::Value *Ptr = Builder.CreateLoad(Addr);
1940 return Address(Ptr, getNaturalTypeAlignment(RefTy->getPointeeType(),
1941 Source, /*forPointee*/ true));
1945 LValue CodeGenFunction::EmitLoadOfReferenceLValue(Address RefAddr,
1946 const ReferenceType *RefTy) {
1947 AlignmentSource Source;
1948 Address Addr = EmitLoadOfReference(RefAddr, RefTy, &Source);
1949 return MakeAddrLValue(Addr, RefTy->getPointeeType(), Source);
1952 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr,
1953 const PointerType *PtrTy,
1954 AlignmentSource *Source) {
1955 llvm::Value *Addr = Builder.CreateLoad(Ptr);
1956 return Address(Addr, getNaturalTypeAlignment(PtrTy->getPointeeType(), Source,
1957 /*forPointeeType=*/true));
1960 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr,
1961 const PointerType *PtrTy) {
1962 AlignmentSource Source;
1963 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &Source);
1964 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), Source);
1967 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
1968 const Expr *E, const VarDecl *VD) {
1969 QualType T = E->getType();
1971 // If it's thread_local, emit a call to its wrapper function instead.
1972 if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
1973 CGF.CGM.getCXXABI().usesThreadWrapperFunction())
1974 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
1976 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
1977 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
1978 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
1979 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
1980 Address Addr(V, Alignment);
1982 // Emit reference to the private copy of the variable if it is an OpenMP
1983 // threadprivate variable.
1984 if (CGF.getLangOpts().OpenMP && VD->hasAttr<OMPThreadPrivateDeclAttr>())
1985 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
1987 if (auto RefTy = VD->getType()->getAs<ReferenceType>()) {
1988 LV = CGF.EmitLoadOfReferenceLValue(Addr, RefTy);
1990 LV = CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
1992 setObjCGCLValueClass(CGF.getContext(), E, LV);
1996 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
1997 const Expr *E, const FunctionDecl *FD) {
1998 llvm::Value *V = CGF.CGM.GetAddrOfFunction(FD);
1999 if (!FD->hasPrototype()) {
2000 if (const FunctionProtoType *Proto =
2001 FD->getType()->getAs<FunctionProtoType>()) {
2002 // Ugly case: for a K&R-style definition, the type of the definition
2003 // isn't the same as the type of a use. Correct for this with a
2005 QualType NoProtoType =
2006 CGF.getContext().getFunctionNoProtoType(Proto->getReturnType());
2007 NoProtoType = CGF.getContext().getPointerType(NoProtoType);
2008 V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType));
2011 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
2012 return CGF.MakeAddrLValue(V, E->getType(), Alignment, AlignmentSource::Decl);
2015 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
2016 llvm::Value *ThisValue) {
2017 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
2018 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
2019 return CGF.EmitLValueForField(LV, FD);
2022 /// Named Registers are named metadata pointing to the register name
2023 /// which will be read from/written to as an argument to the intrinsic
2024 /// @llvm.read/write_register.
2025 /// So far, only the name is being passed down, but other options such as
2026 /// register type, allocation type or even optimization options could be
2027 /// passed down via the metadata node.
2028 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) {
2029 SmallString<64> Name("llvm.named.register.");
2030 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
2031 assert(Asm->getLabel().size() < 64-Name.size() &&
2032 "Register name too big");
2033 Name.append(Asm->getLabel());
2034 llvm::NamedMDNode *M =
2035 CGM.getModule().getOrInsertNamedMetadata(Name);
2036 if (M->getNumOperands() == 0) {
2037 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
2039 llvm::Metadata *Ops[] = {Str};
2040 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
2043 CharUnits Alignment = CGM.getContext().getDeclAlign(VD);
2046 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0));
2047 return LValue::MakeGlobalReg(Address(Ptr, Alignment), VD->getType());
2050 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
2051 const NamedDecl *ND = E->getDecl();
2052 QualType T = E->getType();
2054 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2055 // Global Named registers access via intrinsics only
2056 if (VD->getStorageClass() == SC_Register &&
2057 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
2058 return EmitGlobalNamedRegister(VD, CGM);
2060 // A DeclRefExpr for a reference initialized by a constant expression can
2061 // appear without being odr-used. Directly emit the constant initializer.
2062 const Expr *Init = VD->getAnyInitializer(VD);
2063 if (Init && !isa<ParmVarDecl>(VD) && VD->getType()->isReferenceType() &&
2064 VD->isUsableInConstantExpressions(getContext()) &&
2065 VD->checkInitIsICE() &&
2066 // Do not emit if it is private OpenMP variable.
2067 !(E->refersToEnclosingVariableOrCapture() && CapturedStmtInfo &&
2068 LocalDeclMap.count(VD))) {
2069 llvm::Constant *Val =
2070 CGM.EmitConstantValue(*VD->evaluateValue(), VD->getType(), this);
2071 assert(Val && "failed to emit reference constant expression");
2072 // FIXME: Eventually we will want to emit vector element references.
2074 // Should we be using the alignment of the constant pointer we emitted?
2075 CharUnits Alignment = getNaturalTypeAlignment(E->getType(), nullptr,
2078 return MakeAddrLValue(Address(Val, Alignment), T, AlignmentSource::Decl);
2081 // Check for captured variables.
2082 if (E->refersToEnclosingVariableOrCapture()) {
2083 if (auto *FD = LambdaCaptureFields.lookup(VD))
2084 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
2085 else if (CapturedStmtInfo) {
2086 auto it = LocalDeclMap.find(VD);
2087 if (it != LocalDeclMap.end()) {
2088 if (auto RefTy = VD->getType()->getAs<ReferenceType>()) {
2089 return EmitLoadOfReferenceLValue(it->second, RefTy);
2091 return MakeAddrLValue(it->second, T);
2094 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD),
2095 CapturedStmtInfo->getContextValue());
2096 return MakeAddrLValue(
2097 Address(CapLVal.getPointer(), getContext().getDeclAlign(VD)),
2098 CapLVal.getType(), AlignmentSource::Decl);
2101 assert(isa<BlockDecl>(CurCodeDecl));
2102 Address addr = GetAddrOfBlockDecl(VD, VD->hasAttr<BlocksAttr>());
2103 return MakeAddrLValue(addr, T, AlignmentSource::Decl);
2107 // FIXME: We should be able to assert this for FunctionDecls as well!
2108 // FIXME: We should be able to assert this for all DeclRefExprs, not just
2109 // those with a valid source location.
2110 assert((ND->isUsed(false) || !isa<VarDecl>(ND) ||
2111 !E->getLocation().isValid()) &&
2112 "Should not use decl without marking it used!");
2114 if (ND->hasAttr<WeakRefAttr>()) {
2115 const auto *VD = cast<ValueDecl>(ND);
2116 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD);
2117 return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl);
2120 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2121 // Check if this is a global variable.
2122 if (VD->hasLinkage() || VD->isStaticDataMember())
2123 return EmitGlobalVarDeclLValue(*this, E, VD);
2125 Address addr = Address::invalid();
2127 // The variable should generally be present in the local decl map.
2128 auto iter = LocalDeclMap.find(VD);
2129 if (iter != LocalDeclMap.end()) {
2130 addr = iter->second;
2132 // Otherwise, it might be static local we haven't emitted yet for
2133 // some reason; most likely, because it's in an outer function.
2134 } else if (VD->isStaticLocal()) {
2135 addr = Address(CGM.getOrCreateStaticVarDecl(
2136 *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)),
2137 getContext().getDeclAlign(VD));
2139 // No other cases for now.
2141 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?");
2145 // Check for OpenMP threadprivate variables.
2146 if (getLangOpts().OpenMP && VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2147 return EmitThreadPrivateVarDeclLValue(
2148 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
2152 // Drill into block byref variables.
2153 bool isBlockByref = VD->hasAttr<BlocksAttr>();
2155 addr = emitBlockByrefAddress(addr, VD);
2158 // Drill into reference types.
2160 if (auto RefTy = VD->getType()->getAs<ReferenceType>()) {
2161 LV = EmitLoadOfReferenceLValue(addr, RefTy);
2163 LV = MakeAddrLValue(addr, T, AlignmentSource::Decl);
2166 bool isLocalStorage = VD->hasLocalStorage();
2168 bool NonGCable = isLocalStorage &&
2169 !VD->getType()->isReferenceType() &&
2172 LV.getQuals().removeObjCGCAttr();
2176 bool isImpreciseLifetime =
2177 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
2178 if (isImpreciseLifetime)
2179 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
2180 setObjCGCLValueClass(getContext(), E, LV);
2184 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
2185 return EmitFunctionDeclLValue(*this, E, FD);
2187 llvm_unreachable("Unhandled DeclRefExpr");
2190 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
2191 // __extension__ doesn't affect lvalue-ness.
2192 if (E->getOpcode() == UO_Extension)
2193 return EmitLValue(E->getSubExpr());
2195 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
2196 switch (E->getOpcode()) {
2197 default: llvm_unreachable("Unknown unary operator lvalue!");
2199 QualType T = E->getSubExpr()->getType()->getPointeeType();
2200 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
2202 AlignmentSource AlignSource;
2203 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &AlignSource);
2204 LValue LV = MakeAddrLValue(Addr, T, AlignSource);
2205 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
2207 // We should not generate __weak write barrier on indirect reference
2208 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
2209 // But, we continue to generate __strong write barrier on indirect write
2210 // into a pointer to object.
2211 if (getLangOpts().ObjC1 &&
2212 getLangOpts().getGC() != LangOptions::NonGC &&
2214 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2219 LValue LV = EmitLValue(E->getSubExpr());
2220 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
2222 // __real is valid on scalars. This is a faster way of testing that.
2223 // __imag can only produce an rvalue on scalars.
2224 if (E->getOpcode() == UO_Real &&
2225 !LV.getAddress().getElementType()->isStructTy()) {
2226 assert(E->getSubExpr()->getType()->isArithmeticType());
2230 assert(E->getSubExpr()->getType()->isAnyComplexType());
2233 (E->getOpcode() == UO_Real
2234 ? emitAddrOfRealComponent(LV.getAddress(), LV.getType())
2235 : emitAddrOfImagComponent(LV.getAddress(), LV.getType()));
2236 return MakeAddrLValue(Component, ExprTy, LV.getAlignmentSource());
2240 LValue LV = EmitLValue(E->getSubExpr());
2241 bool isInc = E->getOpcode() == UO_PreInc;
2243 if (E->getType()->isAnyComplexType())
2244 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
2246 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
2252 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
2253 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
2254 E->getType(), AlignmentSource::Decl);
2257 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
2258 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
2259 E->getType(), AlignmentSource::Decl);
2262 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
2263 auto SL = E->getFunctionName();
2264 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr");
2265 StringRef FnName = CurFn->getName();
2266 if (FnName.startswith("\01"))
2267 FnName = FnName.substr(1);
2268 StringRef NameItems[] = {
2269 PredefinedExpr::getIdentTypeName(E->getIdentType()), FnName};
2270 std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
2271 if (CurCodeDecl && isa<BlockDecl>(CurCodeDecl)) {
2272 auto C = CGM.GetAddrOfConstantCString(FnName, GVName.c_str());
2273 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2275 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
2276 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2279 /// Emit a type description suitable for use by a runtime sanitizer library. The
2280 /// format of a type descriptor is
2283 /// { i16 TypeKind, i16 TypeInfo }
2286 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2287 /// integer, 1 for a floating point value, and -1 for anything else.
2288 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2289 // Only emit each type's descriptor once.
2290 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
2293 uint16_t TypeKind = -1;
2294 uint16_t TypeInfo = 0;
2296 if (T->isIntegerType()) {
2298 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2299 (T->isSignedIntegerType() ? 1 : 0);
2300 } else if (T->isFloatingType()) {
2302 TypeInfo = getContext().getTypeSize(T);
2305 // Format the type name as if for a diagnostic, including quotes and
2306 // optionally an 'aka'.
2307 SmallString<32> Buffer;
2308 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2309 (intptr_t)T.getAsOpaquePtr(),
2310 StringRef(), StringRef(), None, Buffer,
2313 llvm::Constant *Components[] = {
2314 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2315 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2317 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2319 auto *GV = new llvm::GlobalVariable(
2320 CGM.getModule(), Descriptor->getType(),
2321 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
2322 GV->setUnnamedAddr(true);
2323 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV);
2325 // Remember the descriptor for this type.
2326 CGM.setTypeDescriptorInMap(T, GV);
2331 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2332 llvm::Type *TargetTy = IntPtrTy;
2334 // Floating-point types which fit into intptr_t are bitcast to integers
2335 // and then passed directly (after zero-extension, if necessary).
2336 if (V->getType()->isFloatingPointTy()) {
2337 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2338 if (Bits <= TargetTy->getIntegerBitWidth())
2339 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2343 // Integers which fit in intptr_t are zero-extended and passed directly.
2344 if (V->getType()->isIntegerTy() &&
2345 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2346 return Builder.CreateZExt(V, TargetTy);
2348 // Pointers are passed directly, everything else is passed by address.
2349 if (!V->getType()->isPointerTy()) {
2350 Address Ptr = CreateDefaultAlignTempAlloca(V->getType());
2351 Builder.CreateStore(V, Ptr);
2352 V = Ptr.getPointer();
2354 return Builder.CreatePtrToInt(V, TargetTy);
2357 /// \brief Emit a representation of a SourceLocation for passing to a handler
2358 /// in a sanitizer runtime library. The format for this data is:
2360 /// struct SourceLocation {
2361 /// const char *Filename;
2362 /// int32_t Line, Column;
2365 /// For an invalid SourceLocation, the Filename pointer is null.
2366 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
2367 llvm::Constant *Filename;
2370 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
2371 if (PLoc.isValid()) {
2372 auto FilenameGV = CGM.GetAddrOfConstantCString(PLoc.getFilename(), ".src");
2373 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
2374 cast<llvm::GlobalVariable>(FilenameGV.getPointer()));
2375 Filename = FilenameGV.getPointer();
2376 Line = PLoc.getLine();
2377 Column = PLoc.getColumn();
2379 Filename = llvm::Constant::getNullValue(Int8PtrTy);
2383 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
2384 Builder.getInt32(Column)};
2386 return llvm::ConstantStruct::getAnon(Data);
2390 /// \brief Specify under what conditions this check can be recovered
2391 enum class CheckRecoverableKind {
2392 /// Always terminate program execution if this check fails.
2394 /// Check supports recovering, runtime has both fatal (noreturn) and
2395 /// non-fatal handlers for this check.
2397 /// Runtime conditionally aborts, always need to support recovery.
2402 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) {
2403 assert(llvm::countPopulation(Kind) == 1);
2405 case SanitizerKind::Vptr:
2406 return CheckRecoverableKind::AlwaysRecoverable;
2407 case SanitizerKind::Return:
2408 case SanitizerKind::Unreachable:
2409 return CheckRecoverableKind::Unrecoverable;
2411 return CheckRecoverableKind::Recoverable;
2415 static void emitCheckHandlerCall(CodeGenFunction &CGF,
2416 llvm::FunctionType *FnType,
2417 ArrayRef<llvm::Value *> FnArgs,
2418 StringRef CheckName,
2419 CheckRecoverableKind RecoverKind, bool IsFatal,
2420 llvm::BasicBlock *ContBB) {
2421 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable);
2422 bool NeedsAbortSuffix =
2423 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable;
2424 std::string FnName = ("__ubsan_handle_" + CheckName +
2425 (NeedsAbortSuffix ? "_abort" : "")).str();
2427 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable;
2429 llvm::AttrBuilder B;
2431 B.addAttribute(llvm::Attribute::NoReturn)
2432 .addAttribute(llvm::Attribute::NoUnwind);
2434 B.addAttribute(llvm::Attribute::UWTable);
2436 llvm::Value *Fn = CGF.CGM.CreateRuntimeFunction(
2438 llvm::AttributeSet::get(CGF.getLLVMContext(),
2439 llvm::AttributeSet::FunctionIndex, B));
2440 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs);
2442 HandlerCall->setDoesNotReturn();
2443 CGF.Builder.CreateUnreachable();
2445 CGF.Builder.CreateBr(ContBB);
2449 void CodeGenFunction::EmitCheck(
2450 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
2451 StringRef CheckName, ArrayRef<llvm::Constant *> StaticArgs,
2452 ArrayRef<llvm::Value *> DynamicArgs) {
2453 assert(IsSanitizerScope);
2454 assert(Checked.size() > 0);
2456 llvm::Value *FatalCond = nullptr;
2457 llvm::Value *RecoverableCond = nullptr;
2458 llvm::Value *TrapCond = nullptr;
2459 for (int i = 0, n = Checked.size(); i < n; ++i) {
2460 llvm::Value *Check = Checked[i].first;
2461 // -fsanitize-trap= overrides -fsanitize-recover=.
2462 llvm::Value *&Cond =
2463 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second)
2465 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second)
2468 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check;
2472 EmitTrapCheck(TrapCond);
2473 if (!FatalCond && !RecoverableCond)
2476 llvm::Value *JointCond;
2477 if (FatalCond && RecoverableCond)
2478 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond);
2480 JointCond = FatalCond ? FatalCond : RecoverableCond;
2483 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second);
2484 // In cross-DSO CFI mode this code is used to generate __cfi_check_fail, which
2485 // includes all checks, even those that are not in SanOpts.
2486 assert(CGM.getCodeGenOpts().SanitizeCfiCrossDso ||
2487 SanOpts.has(Checked[0].second));
2489 for (int i = 1, n = Checked.size(); i < n; ++i) {
2490 assert(RecoverKind == getRecoverableKind(Checked[i].second) &&
2491 "All recoverable kinds in a single check must be same!");
2492 assert(CGM.getCodeGenOpts().SanitizeCfiCrossDso ||
2493 SanOpts.has(Checked[i].second));
2497 llvm::BasicBlock *Cont = createBasicBlock("cont");
2498 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName);
2499 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers);
2500 // Give hint that we very much don't expect to execute the handler
2501 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
2502 llvm::MDBuilder MDHelper(getLLVMContext());
2503 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2504 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
2505 EmitBlock(Handlers);
2507 // Handler functions take an i8* pointing to the (handler-specific) static
2508 // information block, followed by a sequence of intptr_t arguments
2509 // representing operand values.
2510 SmallVector<llvm::Value *, 4> Args;
2511 SmallVector<llvm::Type *, 4> ArgTypes;
2512 Args.reserve(DynamicArgs.size() + 1);
2513 ArgTypes.reserve(DynamicArgs.size() + 1);
2515 // Emit handler arguments and create handler function type.
2516 if (!StaticArgs.empty()) {
2517 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2519 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2520 llvm::GlobalVariable::PrivateLinkage, Info);
2521 InfoPtr->setUnnamedAddr(true);
2522 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
2523 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
2524 ArgTypes.push_back(Int8PtrTy);
2527 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
2528 Args.push_back(EmitCheckValue(DynamicArgs[i]));
2529 ArgTypes.push_back(IntPtrTy);
2532 llvm::FunctionType *FnType =
2533 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
2535 if (!FatalCond || !RecoverableCond) {
2536 // Simple case: we need to generate a single handler call, either
2537 // fatal, or non-fatal.
2538 emitCheckHandlerCall(*this, FnType, Args, CheckName, RecoverKind,
2539 (FatalCond != nullptr), Cont);
2541 // Emit two handler calls: first one for set of unrecoverable checks,
2542 // another one for recoverable.
2543 llvm::BasicBlock *NonFatalHandlerBB =
2544 createBasicBlock("non_fatal." + CheckName);
2545 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName);
2546 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB);
2547 EmitBlock(FatalHandlerBB);
2548 emitCheckHandlerCall(*this, FnType, Args, CheckName, RecoverKind, true,
2550 EmitBlock(NonFatalHandlerBB);
2551 emitCheckHandlerCall(*this, FnType, Args, CheckName, RecoverKind, false,
2558 void CodeGenFunction::EmitCfiSlowPathCheck(
2559 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId,
2560 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) {
2561 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont");
2563 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath");
2564 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB);
2566 llvm::MDBuilder MDHelper(getLLVMContext());
2567 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2568 BI->setMetadata(llvm::LLVMContext::MD_prof, Node);
2572 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind);
2574 llvm::CallInst *CheckCall;
2576 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2578 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2579 llvm::GlobalVariable::PrivateLinkage, Info);
2580 InfoPtr->setUnnamedAddr(true);
2581 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
2583 llvm::Constant *SlowPathDiagFn = CGM.getModule().getOrInsertFunction(
2584 "__cfi_slowpath_diag",
2585 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy},
2587 CheckCall = Builder.CreateCall(
2589 {TypeId, Ptr, Builder.CreateBitCast(InfoPtr, Int8PtrTy)});
2591 llvm::Constant *SlowPathFn = CGM.getModule().getOrInsertFunction(
2593 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false));
2594 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr});
2597 CheckCall->setDoesNotThrow();
2602 // This function is basically a switch over the CFI failure kind, which is
2603 // extracted from CFICheckFailData (1st function argument). Each case is either
2604 // llvm.trap or a call to one of the two runtime handlers, based on
2605 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid
2606 // failure kind) traps, but this should really never happen. CFICheckFailData
2607 // can be nullptr if the calling module has -fsanitize-trap behavior for this
2608 // check kind; in this case __cfi_check_fail traps as well.
2609 void CodeGenFunction::EmitCfiCheckFail() {
2610 SanitizerScope SanScope(this);
2611 FunctionArgList Args;
2612 ImplicitParamDecl ArgData(getContext(), nullptr, SourceLocation(), nullptr,
2613 getContext().VoidPtrTy);
2614 ImplicitParamDecl ArgAddr(getContext(), nullptr, SourceLocation(), nullptr,
2615 getContext().VoidPtrTy);
2616 Args.push_back(&ArgData);
2617 Args.push_back(&ArgAddr);
2619 const CGFunctionInfo &FI =
2620 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args);
2622 llvm::Function *F = llvm::Function::Create(
2623 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false),
2624 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule());
2625 F->setVisibility(llvm::GlobalValue::HiddenVisibility);
2627 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args,
2631 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false,
2632 CGM.getContext().VoidPtrTy, ArgData.getLocation());
2634 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false,
2635 CGM.getContext().VoidPtrTy, ArgAddr.getLocation());
2637 // Data == nullptr means the calling module has trap behaviour for this check.
2638 llvm::Value *DataIsNotNullPtr =
2639 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy));
2640 EmitTrapCheck(DataIsNotNullPtr);
2642 llvm::StructType *SourceLocationTy =
2643 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty, nullptr);
2644 llvm::StructType *CfiCheckFailDataTy =
2645 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy, nullptr);
2647 llvm::Value *V = Builder.CreateConstGEP2_32(
2649 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0,
2651 Address CheckKindAddr(V, getIntAlign());
2652 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr);
2654 llvm::Value *AllVtables = llvm::MetadataAsValue::get(
2655 CGM.getLLVMContext(),
2656 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
2657 llvm::Value *ValidVtable = Builder.CreateZExt(
2658 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::bitset_test),
2659 {Addr, AllVtables}),
2662 const std::pair<int, SanitizerMask> CheckKinds[] = {
2663 {CFITCK_VCall, SanitizerKind::CFIVCall},
2664 {CFITCK_NVCall, SanitizerKind::CFINVCall},
2665 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast},
2666 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast},
2667 {CFITCK_ICall, SanitizerKind::CFIICall}};
2669 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks;
2670 for (auto CheckKindMaskPair : CheckKinds) {
2671 int Kind = CheckKindMaskPair.first;
2672 SanitizerMask Mask = CheckKindMaskPair.second;
2674 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind));
2675 EmitCheck(std::make_pair(Cond, Mask), "cfi_check_fail", {},
2676 {Data, Addr, ValidVtable});
2680 // The only reference to this function will be created during LTO link.
2681 // Make sure it survives until then.
2682 CGM.addUsedGlobal(F);
2685 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
2686 llvm::BasicBlock *Cont = createBasicBlock("cont");
2688 // If we're optimizing, collapse all calls to trap down to just one per
2689 // function to save on code size.
2690 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
2691 TrapBB = createBasicBlock("trap");
2692 Builder.CreateCondBr(Checked, Cont, TrapBB);
2694 llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
2695 TrapCall->setDoesNotReturn();
2696 TrapCall->setDoesNotThrow();
2697 Builder.CreateUnreachable();
2699 Builder.CreateCondBr(Checked, Cont, TrapBB);
2705 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) {
2706 llvm::CallInst *TrapCall = Builder.CreateCall(CGM.getIntrinsic(IntrID));
2708 if (!CGM.getCodeGenOpts().TrapFuncName.empty())
2709 TrapCall->addAttribute(llvm::AttributeSet::FunctionIndex,
2711 CGM.getCodeGenOpts().TrapFuncName);
2716 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E,
2717 AlignmentSource *AlignSource) {
2718 assert(E->getType()->isArrayType() &&
2719 "Array to pointer decay must have array source type!");
2721 // Expressions of array type can't be bitfields or vector elements.
2722 LValue LV = EmitLValue(E);
2723 Address Addr = LV.getAddress();
2724 if (AlignSource) *AlignSource = LV.getAlignmentSource();
2726 // If the array type was an incomplete type, we need to make sure
2727 // the decay ends up being the right type.
2728 llvm::Type *NewTy = ConvertType(E->getType());
2729 Addr = Builder.CreateElementBitCast(Addr, NewTy);
2731 // Note that VLA pointers are always decayed, so we don't need to do
2733 if (!E->getType()->isVariableArrayType()) {
2734 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
2735 "Expected pointer to array");
2736 Addr = Builder.CreateStructGEP(Addr, 0, CharUnits::Zero(), "arraydecay");
2739 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType();
2740 return Builder.CreateElementBitCast(Addr, ConvertTypeForMem(EltType));
2743 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
2744 /// array to pointer, return the array subexpression.
2745 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
2746 // If this isn't just an array->pointer decay, bail out.
2747 const auto *CE = dyn_cast<CastExpr>(E);
2748 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
2751 // If this is a decay from variable width array, bail out.
2752 const Expr *SubExpr = CE->getSubExpr();
2753 if (SubExpr->getType()->isVariableArrayType())
2759 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
2761 ArrayRef<llvm::Value*> indices,
2763 const llvm::Twine &name = "arrayidx") {
2765 return CGF.Builder.CreateInBoundsGEP(ptr, indices, name);
2767 return CGF.Builder.CreateGEP(ptr, indices, name);
2771 static CharUnits getArrayElementAlign(CharUnits arrayAlign,
2773 CharUnits eltSize) {
2774 // If we have a constant index, we can use the exact offset of the
2775 // element we're accessing.
2776 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) {
2777 CharUnits offset = constantIdx->getZExtValue() * eltSize;
2778 return arrayAlign.alignmentAtOffset(offset);
2780 // Otherwise, use the worst-case alignment for any element.
2782 return arrayAlign.alignmentOfArrayElement(eltSize);
2786 static QualType getFixedSizeElementType(const ASTContext &ctx,
2787 const VariableArrayType *vla) {
2790 eltType = vla->getElementType();
2791 } while ((vla = ctx.getAsVariableArrayType(eltType)));
2795 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
2796 ArrayRef<llvm::Value*> indices,
2797 QualType eltType, bool inbounds,
2798 const llvm::Twine &name = "arrayidx") {
2799 // All the indices except that last must be zero.
2801 for (auto idx : indices.drop_back())
2802 assert(isa<llvm::ConstantInt>(idx) &&
2803 cast<llvm::ConstantInt>(idx)->isZero());
2806 // Determine the element size of the statically-sized base. This is
2807 // the thing that the indices are expressed in terms of.
2808 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) {
2809 eltType = getFixedSizeElementType(CGF.getContext(), vla);
2812 // We can use that to compute the best alignment of the element.
2813 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
2814 CharUnits eltAlign =
2815 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
2817 llvm::Value *eltPtr =
2818 emitArraySubscriptGEP(CGF, addr.getPointer(), indices, inbounds, name);
2819 return Address(eltPtr, eltAlign);
2822 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
2824 // The index must always be an integer, which is not an aggregate. Emit it.
2825 llvm::Value *Idx = EmitScalarExpr(E->getIdx());
2826 QualType IdxTy = E->getIdx()->getType();
2827 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
2829 if (SanOpts.has(SanitizerKind::ArrayBounds))
2830 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
2832 // If the base is a vector type, then we are forming a vector element lvalue
2833 // with this subscript.
2834 if (E->getBase()->getType()->isVectorType() &&
2835 !isa<ExtVectorElementExpr>(E->getBase())) {
2836 // Emit the vector as an lvalue to get its address.
2837 LValue LHS = EmitLValue(E->getBase());
2838 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
2839 return LValue::MakeVectorElt(LHS.getAddress(), Idx,
2840 E->getBase()->getType(),
2841 LHS.getAlignmentSource());
2844 // All the other cases basically behave like simple offsetting.
2846 // Extend or truncate the index type to 32 or 64-bits.
2847 if (Idx->getType() != IntPtrTy)
2848 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
2850 // Handle the extvector case we ignored above.
2851 if (isa<ExtVectorElementExpr>(E->getBase())) {
2852 LValue LV = EmitLValue(E->getBase());
2853 Address Addr = EmitExtVectorElementLValue(LV);
2855 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
2856 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true);
2857 return MakeAddrLValue(Addr, EltType, LV.getAlignmentSource());
2860 AlignmentSource AlignSource;
2861 Address Addr = Address::invalid();
2862 if (const VariableArrayType *vla =
2863 getContext().getAsVariableArrayType(E->getType())) {
2864 // The base must be a pointer, which is not an aggregate. Emit
2865 // it. It needs to be emitted first in case it's what captures
2867 Addr = EmitPointerWithAlignment(E->getBase(), &AlignSource);
2869 // The element count here is the total number of non-VLA elements.
2870 llvm::Value *numElements = getVLASize(vla).first;
2872 // Effectively, the multiply by the VLA size is part of the GEP.
2873 // GEP indexes are signed, and scaling an index isn't permitted to
2874 // signed-overflow, so we use the same semantics for our explicit
2875 // multiply. We suppress this if overflow is not undefined behavior.
2876 if (getLangOpts().isSignedOverflowDefined()) {
2877 Idx = Builder.CreateMul(Idx, numElements);
2879 Idx = Builder.CreateNSWMul(Idx, numElements);
2882 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
2883 !getLangOpts().isSignedOverflowDefined());
2885 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
2886 // Indexing over an interface, as in "NSString *P; P[4];"
2887 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT);
2888 llvm::Value *InterfaceSizeVal =
2889 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity());;
2891 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal);
2893 // Emit the base pointer.
2894 Addr = EmitPointerWithAlignment(E->getBase(), &AlignSource);
2896 // We don't necessarily build correct LLVM struct types for ObjC
2897 // interfaces, so we can't rely on GEP to do this scaling
2898 // correctly, so we need to cast to i8*. FIXME: is this actually
2899 // true? A lot of other things in the fragile ABI would break...
2900 llvm::Type *OrigBaseTy = Addr.getType();
2901 Addr = Builder.CreateElementBitCast(Addr, Int8Ty);
2904 CharUnits EltAlign =
2905 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
2906 llvm::Value *EltPtr =
2907 emitArraySubscriptGEP(*this, Addr.getPointer(), ScaledIdx, false);
2908 Addr = Address(EltPtr, EltAlign);
2911 Addr = Builder.CreateBitCast(Addr, OrigBaseTy);
2912 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
2913 // If this is A[i] where A is an array, the frontend will have decayed the
2914 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
2915 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
2916 // "gep x, i" here. Emit one "gep A, 0, i".
2917 assert(Array->getType()->isArrayType() &&
2918 "Array to pointer decay must have array source type!");
2920 // For simple multidimensional array indexing, set the 'accessed' flag for
2921 // better bounds-checking of the base expression.
2922 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
2923 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
2925 ArrayLV = EmitLValue(Array);
2927 // Propagate the alignment from the array itself to the result.
2928 Addr = emitArraySubscriptGEP(*this, ArrayLV.getAddress(),
2929 {CGM.getSize(CharUnits::Zero()), Idx},
2931 !getLangOpts().isSignedOverflowDefined());
2932 AlignSource = ArrayLV.getAlignmentSource();
2934 // The base must be a pointer; emit it with an estimate of its alignment.
2935 Addr = EmitPointerWithAlignment(E->getBase(), &AlignSource);
2936 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
2937 !getLangOpts().isSignedOverflowDefined());
2940 LValue LV = MakeAddrLValue(Addr, E->getType(), AlignSource);
2942 // TODO: Preserve/extend path TBAA metadata?
2944 if (getLangOpts().ObjC1 &&
2945 getLangOpts().getGC() != LangOptions::NonGC) {
2946 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2947 setObjCGCLValueClass(getContext(), E, LV);
2952 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base,
2953 AlignmentSource &AlignSource,
2954 QualType BaseTy, QualType ElTy,
2955 bool IsLowerBound) {
2957 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) {
2958 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound);
2959 if (BaseTy->isArrayType()) {
2960 Address Addr = BaseLVal.getAddress();
2961 AlignSource = BaseLVal.getAlignmentSource();
2963 // If the array type was an incomplete type, we need to make sure
2964 // the decay ends up being the right type.
2965 llvm::Type *NewTy = CGF.ConvertType(BaseTy);
2966 Addr = CGF.Builder.CreateElementBitCast(Addr, NewTy);
2968 // Note that VLA pointers are always decayed, so we don't need to do
2970 if (!BaseTy->isVariableArrayType()) {
2971 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
2972 "Expected pointer to array");
2973 Addr = CGF.Builder.CreateStructGEP(Addr, 0, CharUnits::Zero(),
2977 return CGF.Builder.CreateElementBitCast(Addr,
2978 CGF.ConvertTypeForMem(ElTy));
2980 CharUnits Align = CGF.getNaturalTypeAlignment(ElTy, &AlignSource);
2981 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress()), Align);
2983 return CGF.EmitPointerWithAlignment(Base, &AlignSource);
2986 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
2987 bool IsLowerBound) {
2990 dyn_cast<OMPArraySectionExpr>(E->getBase()->IgnoreParenImpCasts()))
2991 BaseTy = OMPArraySectionExpr::getBaseOriginalType(ASE);
2993 BaseTy = E->getBase()->getType();
2994 QualType ResultExprTy;
2995 if (auto *AT = getContext().getAsArrayType(BaseTy))
2996 ResultExprTy = AT->getElementType();
2998 ResultExprTy = BaseTy->getPointeeType();
2999 llvm::Value *Idx = nullptr;
3000 if (IsLowerBound || (!IsLowerBound && E->getColonLoc().isInvalid())) {
3001 // Requesting lower bound or upper bound, but without provided length and
3002 // without ':' symbol for the default length -> length = 1.
3003 // Idx = LowerBound ?: 0;
3004 if (auto *LowerBound = E->getLowerBound()) {
3005 Idx = Builder.CreateIntCast(
3006 EmitScalarExpr(LowerBound), IntPtrTy,
3007 LowerBound->getType()->hasSignedIntegerRepresentation());
3009 Idx = llvm::ConstantInt::getNullValue(IntPtrTy);
3011 // Try to emit length or lower bound as constant. If this is possible, 1
3012 // is subtracted from constant length or lower bound. Otherwise, emit LLVM
3013 // IR (LB + Len) - 1.
3014 auto &C = CGM.getContext();
3015 auto *Length = E->getLength();
3016 llvm::APSInt ConstLength;
3018 // Idx = LowerBound + Length - 1;
3019 if (Length->isIntegerConstantExpr(ConstLength, C)) {
3020 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3023 auto *LowerBound = E->getLowerBound();
3024 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false);
3025 if (LowerBound && LowerBound->isIntegerConstantExpr(ConstLowerBound, C)) {
3026 ConstLowerBound = ConstLowerBound.zextOrTrunc(PointerWidthInBits);
3027 LowerBound = nullptr;
3031 else if (!LowerBound)
3034 if (Length || LowerBound) {
3035 auto *LowerBoundVal =
3037 ? Builder.CreateIntCast(
3038 EmitScalarExpr(LowerBound), IntPtrTy,
3039 LowerBound->getType()->hasSignedIntegerRepresentation())
3040 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound);
3043 ? Builder.CreateIntCast(
3044 EmitScalarExpr(Length), IntPtrTy,
3045 Length->getType()->hasSignedIntegerRepresentation())
3046 : llvm::ConstantInt::get(IntPtrTy, ConstLength);
3047 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len",
3049 !getLangOpts().isSignedOverflowDefined());
3050 if (Length && LowerBound) {
3051 Idx = Builder.CreateSub(
3052 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1",
3053 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3056 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound);
3058 // Idx = ArraySize - 1;
3059 QualType ArrayTy = BaseTy->isPointerType()
3060 ? E->getBase()->IgnoreParenImpCasts()->getType()
3062 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) {
3063 Length = VAT->getSizeExpr();
3064 if (Length->isIntegerConstantExpr(ConstLength, C))
3067 auto *CAT = C.getAsConstantArrayType(ArrayTy);
3068 ConstLength = CAT->getSize();
3071 auto *LengthVal = Builder.CreateIntCast(
3072 EmitScalarExpr(Length), IntPtrTy,
3073 Length->getType()->hasSignedIntegerRepresentation());
3074 Idx = Builder.CreateSub(
3075 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1",
3076 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3078 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3080 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength);
3086 Address EltPtr = Address::invalid();
3087 AlignmentSource AlignSource;
3088 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) {
3089 // The base must be a pointer, which is not an aggregate. Emit
3090 // it. It needs to be emitted first in case it's what captures
3093 emitOMPArraySectionBase(*this, E->getBase(), AlignSource, BaseTy,
3094 VLA->getElementType(), IsLowerBound);
3095 // The element count here is the total number of non-VLA elements.
3096 llvm::Value *NumElements = getVLASize(VLA).first;
3098 // Effectively, the multiply by the VLA size is part of the GEP.
3099 // GEP indexes are signed, and scaling an index isn't permitted to
3100 // signed-overflow, so we use the same semantics for our explicit
3101 // multiply. We suppress this if overflow is not undefined behavior.
3102 if (getLangOpts().isSignedOverflowDefined())
3103 Idx = Builder.CreateMul(Idx, NumElements);
3105 Idx = Builder.CreateNSWMul(Idx, NumElements);
3106 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
3107 !getLangOpts().isSignedOverflowDefined());
3108 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3109 // If this is A[i] where A is an array, the frontend will have decayed the
3110 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3111 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3112 // "gep x, i" here. Emit one "gep A, 0, i".
3113 assert(Array->getType()->isArrayType() &&
3114 "Array to pointer decay must have array source type!");
3116 // For simple multidimensional array indexing, set the 'accessed' flag for
3117 // better bounds-checking of the base expression.
3118 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3119 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3121 ArrayLV = EmitLValue(Array);
3123 // Propagate the alignment from the array itself to the result.
3124 EltPtr = emitArraySubscriptGEP(
3125 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3126 ResultExprTy, !getLangOpts().isSignedOverflowDefined());
3127 AlignSource = ArrayLV.getAlignmentSource();
3129 Address Base = emitOMPArraySectionBase(*this, E->getBase(), AlignSource,
3130 BaseTy, ResultExprTy, IsLowerBound);
3131 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
3132 !getLangOpts().isSignedOverflowDefined());
3135 return MakeAddrLValue(EltPtr, ResultExprTy, AlignSource);
3138 LValue CodeGenFunction::
3139 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
3140 // Emit the base vector as an l-value.
3143 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
3145 // If it is a pointer to a vector, emit the address and form an lvalue with
3147 AlignmentSource AlignSource;
3148 Address Ptr = EmitPointerWithAlignment(E->getBase(), &AlignSource);
3149 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
3150 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), AlignSource);
3151 Base.getQuals().removeObjCGCAttr();
3152 } else if (E->getBase()->isGLValue()) {
3153 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
3154 // emit the base as an lvalue.
3155 assert(E->getBase()->getType()->isVectorType());
3156 Base = EmitLValue(E->getBase());
3158 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
3159 assert(E->getBase()->getType()->isVectorType() &&
3160 "Result must be a vector");
3161 llvm::Value *Vec = EmitScalarExpr(E->getBase());
3163 // Store the vector to memory (because LValue wants an address).
3164 Address VecMem = CreateMemTemp(E->getBase()->getType());
3165 Builder.CreateStore(Vec, VecMem);
3166 Base = MakeAddrLValue(VecMem, E->getBase()->getType(),
3167 AlignmentSource::Decl);
3171 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
3173 // Encode the element access list into a vector of unsigned indices.
3174 SmallVector<uint32_t, 4> Indices;
3175 E->getEncodedElementAccess(Indices);
3177 if (Base.isSimple()) {
3178 llvm::Constant *CV =
3179 llvm::ConstantDataVector::get(getLLVMContext(), Indices);
3180 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
3181 Base.getAlignmentSource());
3183 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
3185 llvm::Constant *BaseElts = Base.getExtVectorElts();
3186 SmallVector<llvm::Constant *, 4> CElts;
3188 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
3189 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
3190 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
3191 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type,
3192 Base.getAlignmentSource());
3195 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
3196 Expr *BaseExpr = E->getBase();
3198 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
3201 AlignmentSource AlignSource;
3202 Address Addr = EmitPointerWithAlignment(BaseExpr, &AlignSource);
3203 QualType PtrTy = BaseExpr->getType()->getPointeeType();
3204 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy);
3205 BaseLV = MakeAddrLValue(Addr, PtrTy, AlignSource);
3207 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
3209 NamedDecl *ND = E->getMemberDecl();
3210 if (auto *Field = dyn_cast<FieldDecl>(ND)) {
3211 LValue LV = EmitLValueForField(BaseLV, Field);
3212 setObjCGCLValueClass(getContext(), E, LV);
3216 if (auto *VD = dyn_cast<VarDecl>(ND))
3217 return EmitGlobalVarDeclLValue(*this, E, VD);
3219 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
3220 return EmitFunctionDeclLValue(*this, E, FD);
3222 llvm_unreachable("Unhandled member declaration!");
3225 /// Given that we are currently emitting a lambda, emit an l-value for
3226 /// one of its members.
3227 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
3228 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
3229 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
3230 QualType LambdaTagType =
3231 getContext().getTagDeclType(Field->getParent());
3232 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
3233 return EmitLValueForField(LambdaLV, Field);
3236 /// Drill down to the storage of a field without walking into
3237 /// reference types.
3239 /// The resulting address doesn't necessarily have the right type.
3240 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
3241 const FieldDecl *field) {
3242 const RecordDecl *rec = field->getParent();
3245 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
3248 // Adjust the alignment down to the given offset.
3249 // As a special case, if the LLVM field index is 0, we know that this
3251 assert((idx != 0 || CGF.getContext().getASTRecordLayout(rec)
3252 .getFieldOffset(field->getFieldIndex()) == 0) &&
3253 "LLVM field at index zero had non-zero offset?");
3255 auto &recLayout = CGF.getContext().getASTRecordLayout(rec);
3256 auto offsetInBits = recLayout.getFieldOffset(field->getFieldIndex());
3257 offset = CGF.getContext().toCharUnitsFromBits(offsetInBits);
3260 return CGF.Builder.CreateStructGEP(base, idx, offset, field->getName());
3263 LValue CodeGenFunction::EmitLValueForField(LValue base,
3264 const FieldDecl *field) {
3265 AlignmentSource fieldAlignSource =
3266 getFieldAlignmentSource(base.getAlignmentSource());
3268 if (field->isBitField()) {
3269 const CGRecordLayout &RL =
3270 CGM.getTypes().getCGRecordLayout(field->getParent());
3271 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
3272 Address Addr = base.getAddress();
3273 unsigned Idx = RL.getLLVMFieldNo(field);
3275 // For structs, we GEP to the field that the record layout suggests.
3276 Addr = Builder.CreateStructGEP(Addr, Idx, Info.StorageOffset,
3278 // Get the access type.
3279 llvm::Type *FieldIntTy =
3280 llvm::Type::getIntNTy(getLLVMContext(), Info.StorageSize);
3281 if (Addr.getElementType() != FieldIntTy)
3282 Addr = Builder.CreateElementBitCast(Addr, FieldIntTy);
3284 QualType fieldType =
3285 field->getType().withCVRQualifiers(base.getVRQualifiers());
3286 return LValue::MakeBitfield(Addr, Info, fieldType, fieldAlignSource);
3289 const RecordDecl *rec = field->getParent();
3290 QualType type = field->getType();
3292 bool mayAlias = rec->hasAttr<MayAliasAttr>();
3294 Address addr = base.getAddress();
3295 unsigned cvr = base.getVRQualifiers();
3296 bool TBAAPath = CGM.getCodeGenOpts().StructPathTBAA;
3297 if (rec->isUnion()) {
3298 // For unions, there is no pointer adjustment.
3299 assert(!type->isReferenceType() && "union has reference member");
3300 // TODO: handle path-aware TBAA for union.
3303 // For structs, we GEP to the field that the record layout suggests.
3304 addr = emitAddrOfFieldStorage(*this, addr, field);
3306 // If this is a reference field, load the reference right now.
3307 if (const ReferenceType *refType = type->getAs<ReferenceType>()) {
3308 llvm::LoadInst *load = Builder.CreateLoad(addr, "ref");
3309 if (cvr & Qualifiers::Volatile) load->setVolatile(true);
3311 // Loading the reference will disable path-aware TBAA.
3313 if (CGM.shouldUseTBAA()) {
3316 tbaa = CGM.getTBAAInfo(getContext().CharTy);
3318 tbaa = CGM.getTBAAInfo(type);
3320 CGM.DecorateInstructionWithTBAA(load, tbaa);
3324 type = refType->getPointeeType();
3326 CharUnits alignment =
3327 getNaturalTypeAlignment(type, &fieldAlignSource, /*pointee*/ true);
3328 addr = Address(load, alignment);
3330 // Qualifiers on the struct don't apply to the referencee, and
3331 // we'll pick up CVR from the actual type later, so reset these
3332 // additional qualifiers now.
3337 // Make sure that the address is pointing to the right type. This is critical
3338 // for both unions and structs. A union needs a bitcast, a struct element
3339 // will need a bitcast if the LLVM type laid out doesn't match the desired
3341 addr = Builder.CreateElementBitCast(addr,
3342 CGM.getTypes().ConvertTypeForMem(type),
3345 if (field->hasAttr<AnnotateAttr>())
3346 addr = EmitFieldAnnotations(field, addr);
3348 LValue LV = MakeAddrLValue(addr, type, fieldAlignSource);
3349 LV.getQuals().addCVRQualifiers(cvr);
3351 const ASTRecordLayout &Layout =
3352 getContext().getASTRecordLayout(field->getParent());
3353 // Set the base type to be the base type of the base LValue and
3354 // update offset to be relative to the base type.
3355 LV.setTBAABaseType(mayAlias ? getContext().CharTy : base.getTBAABaseType());
3356 LV.setTBAAOffset(mayAlias ? 0 : base.getTBAAOffset() +
3357 Layout.getFieldOffset(field->getFieldIndex()) /
3358 getContext().getCharWidth());
3361 // __weak attribute on a field is ignored.
3362 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
3363 LV.getQuals().removeObjCGCAttr();
3365 // Fields of may_alias structs act like 'char' for TBAA purposes.
3366 // FIXME: this should get propagated down through anonymous structs
3368 if (mayAlias && LV.getTBAAInfo())
3369 LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy));
3375 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
3376 const FieldDecl *Field) {
3377 QualType FieldType = Field->getType();
3379 if (!FieldType->isReferenceType())
3380 return EmitLValueForField(Base, Field);
3382 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(), Field);
3384 // Make sure that the address is pointing to the right type.
3385 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
3386 V = Builder.CreateElementBitCast(V, llvmType, Field->getName());
3388 // TODO: access-path TBAA?
3389 auto FieldAlignSource = getFieldAlignmentSource(Base.getAlignmentSource());
3390 return MakeAddrLValue(V, FieldType, FieldAlignSource);
3393 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
3394 if (E->isFileScope()) {
3395 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
3396 return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl);
3398 if (E->getType()->isVariablyModifiedType())
3399 // make sure to emit the VLA size.
3400 EmitVariablyModifiedType(E->getType());
3402 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
3403 const Expr *InitExpr = E->getInitializer();
3404 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl);
3406 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
3412 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
3413 if (!E->isGLValue())
3414 // Initializing an aggregate temporary in C++11: T{...}.
3415 return EmitAggExprToLValue(E);
3417 // An lvalue initializer list must be initializing a reference.
3418 assert(E->getNumInits() == 1 && "reference init with multiple values");
3419 return EmitLValue(E->getInit(0));
3422 /// Emit the operand of a glvalue conditional operator. This is either a glvalue
3423 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no
3424 /// LValue is returned and the current block has been terminated.
3425 static Optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
3426 const Expr *Operand) {
3427 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
3428 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
3432 return CGF.EmitLValue(Operand);
3435 LValue CodeGenFunction::
3436 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
3437 if (!expr->isGLValue()) {
3438 // ?: here should be an aggregate.
3439 assert(hasAggregateEvaluationKind(expr->getType()) &&
3440 "Unexpected conditional operator!");
3441 return EmitAggExprToLValue(expr);
3444 OpaqueValueMapping binding(*this, expr);
3446 const Expr *condExpr = expr->getCond();
3448 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
3449 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
3450 if (!CondExprBool) std::swap(live, dead);
3452 if (!ContainsLabel(dead)) {
3453 // If the true case is live, we need to track its region.
3455 incrementProfileCounter(expr);
3456 return EmitLValue(live);
3460 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
3461 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
3462 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
3464 ConditionalEvaluation eval(*this);
3465 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock, getProfileCount(expr));
3467 // Any temporaries created here are conditional.
3468 EmitBlock(lhsBlock);
3469 incrementProfileCounter(expr);
3471 Optional<LValue> lhs =
3472 EmitLValueOrThrowExpression(*this, expr->getTrueExpr());
3475 if (lhs && !lhs->isSimple())
3476 return EmitUnsupportedLValue(expr, "conditional operator");
3478 lhsBlock = Builder.GetInsertBlock();
3480 Builder.CreateBr(contBlock);
3482 // Any temporaries created here are conditional.
3483 EmitBlock(rhsBlock);
3485 Optional<LValue> rhs =
3486 EmitLValueOrThrowExpression(*this, expr->getFalseExpr());
3488 if (rhs && !rhs->isSimple())
3489 return EmitUnsupportedLValue(expr, "conditional operator");
3490 rhsBlock = Builder.GetInsertBlock();
3492 EmitBlock(contBlock);
3495 llvm::PHINode *phi = Builder.CreatePHI(lhs->getPointer()->getType(),
3497 phi->addIncoming(lhs->getPointer(), lhsBlock);
3498 phi->addIncoming(rhs->getPointer(), rhsBlock);
3499 Address result(phi, std::min(lhs->getAlignment(), rhs->getAlignment()));
3500 AlignmentSource alignSource =
3501 std::max(lhs->getAlignmentSource(), rhs->getAlignmentSource());
3502 return MakeAddrLValue(result, expr->getType(), alignSource);
3504 assert((lhs || rhs) &&
3505 "both operands of glvalue conditional are throw-expressions?");
3506 return lhs ? *lhs : *rhs;
3510 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
3511 /// type. If the cast is to a reference, we can have the usual lvalue result,
3512 /// otherwise if a cast is needed by the code generator in an lvalue context,
3513 /// then it must mean that we need the address of an aggregate in order to
3514 /// access one of its members. This can happen for all the reasons that casts
3515 /// are permitted with aggregate result, including noop aggregate casts, and
3516 /// cast from scalar to union.
3517 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
3518 switch (E->getCastKind()) {
3521 case CK_ArrayToPointerDecay:
3522 case CK_FunctionToPointerDecay:
3523 case CK_NullToMemberPointer:
3524 case CK_NullToPointer:
3525 case CK_IntegralToPointer:
3526 case CK_PointerToIntegral:
3527 case CK_PointerToBoolean:
3528 case CK_VectorSplat:
3529 case CK_IntegralCast:
3530 case CK_BooleanToSignedIntegral:
3531 case CK_IntegralToBoolean:
3532 case CK_IntegralToFloating:
3533 case CK_FloatingToIntegral:
3534 case CK_FloatingToBoolean:
3535 case CK_FloatingCast:
3536 case CK_FloatingRealToComplex:
3537 case CK_FloatingComplexToReal:
3538 case CK_FloatingComplexToBoolean:
3539 case CK_FloatingComplexCast:
3540 case CK_FloatingComplexToIntegralComplex:
3541 case CK_IntegralRealToComplex:
3542 case CK_IntegralComplexToReal:
3543 case CK_IntegralComplexToBoolean:
3544 case CK_IntegralComplexCast:
3545 case CK_IntegralComplexToFloatingComplex:
3546 case CK_DerivedToBaseMemberPointer:
3547 case CK_BaseToDerivedMemberPointer:
3548 case CK_MemberPointerToBoolean:
3549 case CK_ReinterpretMemberPointer:
3550 case CK_AnyPointerToBlockPointerCast:
3551 case CK_ARCProduceObject:
3552 case CK_ARCConsumeObject:
3553 case CK_ARCReclaimReturnedObject:
3554 case CK_ARCExtendBlockObject:
3555 case CK_CopyAndAutoreleaseBlockObject:
3556 case CK_AddressSpaceConversion:
3557 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
3560 llvm_unreachable("dependent cast kind in IR gen!");
3562 case CK_BuiltinFnToFnPtr:
3563 llvm_unreachable("builtin functions are handled elsewhere");
3565 // These are never l-values; just use the aggregate emission code.
3566 case CK_NonAtomicToAtomic:
3567 case CK_AtomicToNonAtomic:
3568 return EmitAggExprToLValue(E);
3571 LValue LV = EmitLValue(E->getSubExpr());
3572 Address V = LV.getAddress();
3573 const auto *DCE = cast<CXXDynamicCastExpr>(E);
3574 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType());
3577 case CK_ConstructorConversion:
3578 case CK_UserDefinedConversion:
3579 case CK_CPointerToObjCPointerCast:
3580 case CK_BlockPointerToObjCPointerCast:
3582 case CK_LValueToRValue:
3583 return EmitLValue(E->getSubExpr());
3585 case CK_UncheckedDerivedToBase:
3586 case CK_DerivedToBase: {
3587 const RecordType *DerivedClassTy =
3588 E->getSubExpr()->getType()->getAs<RecordType>();
3589 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
3591 LValue LV = EmitLValue(E->getSubExpr());
3592 Address This = LV.getAddress();
3594 // Perform the derived-to-base conversion
3595 Address Base = GetAddressOfBaseClass(
3596 This, DerivedClassDecl, E->path_begin(), E->path_end(),
3597 /*NullCheckValue=*/false, E->getExprLoc());
3599 return MakeAddrLValue(Base, E->getType(), LV.getAlignmentSource());
3602 return EmitAggExprToLValue(E);
3603 case CK_BaseToDerived: {
3604 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
3605 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
3607 LValue LV = EmitLValue(E->getSubExpr());
3609 // Perform the base-to-derived conversion
3611 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
3612 E->path_begin(), E->path_end(),
3613 /*NullCheckValue=*/false);
3615 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
3616 // performed and the object is not of the derived type.
3617 if (sanitizePerformTypeCheck())
3618 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
3619 Derived.getPointer(), E->getType());
3621 if (SanOpts.has(SanitizerKind::CFIDerivedCast))
3622 EmitVTablePtrCheckForCast(E->getType(), Derived.getPointer(),
3623 /*MayBeNull=*/false,
3624 CFITCK_DerivedCast, E->getLocStart());
3626 return MakeAddrLValue(Derived, E->getType(), LV.getAlignmentSource());
3628 case CK_LValueBitCast: {
3629 // This must be a reinterpret_cast (or c-style equivalent).
3630 const auto *CE = cast<ExplicitCastExpr>(E);
3632 CGM.EmitExplicitCastExprType(CE, this);
3633 LValue LV = EmitLValue(E->getSubExpr());
3634 Address V = Builder.CreateBitCast(LV.getAddress(),
3635 ConvertType(CE->getTypeAsWritten()));
3637 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast))
3638 EmitVTablePtrCheckForCast(E->getType(), V.getPointer(),
3639 /*MayBeNull=*/false,
3640 CFITCK_UnrelatedCast, E->getLocStart());
3642 return MakeAddrLValue(V, E->getType(), LV.getAlignmentSource());
3644 case CK_ObjCObjectLValueCast: {
3645 LValue LV = EmitLValue(E->getSubExpr());
3646 Address V = Builder.CreateElementBitCast(LV.getAddress(),
3647 ConvertType(E->getType()));
3648 return MakeAddrLValue(V, E->getType(), LV.getAlignmentSource());
3650 case CK_ZeroToOCLEvent:
3651 llvm_unreachable("NULL to OpenCL event lvalue cast is not valid");
3654 llvm_unreachable("Unhandled lvalue cast kind?");
3657 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
3658 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
3659 return getOpaqueLValueMapping(e);
3662 RValue CodeGenFunction::EmitRValueForField(LValue LV,
3663 const FieldDecl *FD,
3664 SourceLocation Loc) {
3665 QualType FT = FD->getType();
3666 LValue FieldLV = EmitLValueForField(LV, FD);
3667 switch (getEvaluationKind(FT)) {
3669 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
3671 return FieldLV.asAggregateRValue();
3673 return EmitLoadOfLValue(FieldLV, Loc);
3675 llvm_unreachable("bad evaluation kind");
3678 //===--------------------------------------------------------------------===//
3679 // Expression Emission
3680 //===--------------------------------------------------------------------===//
3682 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
3683 ReturnValueSlot ReturnValue) {
3684 // Builtins never have block type.
3685 if (E->getCallee()->getType()->isBlockPointerType())
3686 return EmitBlockCallExpr(E, ReturnValue);
3688 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
3689 return EmitCXXMemberCallExpr(CE, ReturnValue);
3691 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
3692 return EmitCUDAKernelCallExpr(CE, ReturnValue);
3694 const Decl *TargetDecl = E->getCalleeDecl();
3695 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl)) {
3696 if (unsigned builtinID = FD->getBuiltinID())
3697 return EmitBuiltinExpr(FD, builtinID, E, ReturnValue);
3700 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
3701 if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
3702 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
3704 if (const auto *PseudoDtor =
3705 dyn_cast<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) {
3706 QualType DestroyedType = PseudoDtor->getDestroyedType();
3707 if (DestroyedType.hasStrongOrWeakObjCLifetime()) {
3708 // Automatic Reference Counting:
3709 // If the pseudo-expression names a retainable object with weak or
3710 // strong lifetime, the object shall be released.
3711 Expr *BaseExpr = PseudoDtor->getBase();
3712 Address BaseValue = Address::invalid();
3713 Qualifiers BaseQuals;
3715 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
3716 if (PseudoDtor->isArrow()) {
3717 BaseValue = EmitPointerWithAlignment(BaseExpr);
3718 const PointerType *PTy = BaseExpr->getType()->getAs<PointerType>();
3719 BaseQuals = PTy->getPointeeType().getQualifiers();
3721 LValue BaseLV = EmitLValue(BaseExpr);
3722 BaseValue = BaseLV.getAddress();
3723 QualType BaseTy = BaseExpr->getType();
3724 BaseQuals = BaseTy.getQualifiers();
3727 switch (DestroyedType.getObjCLifetime()) {
3728 case Qualifiers::OCL_None:
3729 case Qualifiers::OCL_ExplicitNone:
3730 case Qualifiers::OCL_Autoreleasing:
3733 case Qualifiers::OCL_Strong:
3734 EmitARCRelease(Builder.CreateLoad(BaseValue,
3735 PseudoDtor->getDestroyedType().isVolatileQualified()),
3736 ARCPreciseLifetime);
3739 case Qualifiers::OCL_Weak:
3740 EmitARCDestroyWeak(BaseValue);
3744 // C++ [expr.pseudo]p1:
3745 // The result shall only be used as the operand for the function call
3746 // operator (), and the result of such a call has type void. The only
3747 // effect is the evaluation of the postfix-expression before the dot or
3749 EmitScalarExpr(E->getCallee());
3752 return RValue::get(nullptr);
3755 llvm::Value *Callee = EmitScalarExpr(E->getCallee());
3756 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue,
3760 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
3761 // Comma expressions just emit their LHS then their RHS as an l-value.
3762 if (E->getOpcode() == BO_Comma) {
3763 EmitIgnoredExpr(E->getLHS());
3764 EnsureInsertPoint();
3765 return EmitLValue(E->getRHS());
3768 if (E->getOpcode() == BO_PtrMemD ||
3769 E->getOpcode() == BO_PtrMemI)
3770 return EmitPointerToDataMemberBinaryExpr(E);
3772 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
3774 // Note that in all of these cases, __block variables need the RHS
3775 // evaluated first just in case the variable gets moved by the RHS.
3777 switch (getEvaluationKind(E->getType())) {
3779 switch (E->getLHS()->getType().getObjCLifetime()) {
3780 case Qualifiers::OCL_Strong:
3781 return EmitARCStoreStrong(E, /*ignored*/ false).first;
3783 case Qualifiers::OCL_Autoreleasing:
3784 return EmitARCStoreAutoreleasing(E).first;
3786 // No reason to do any of these differently.
3787 case Qualifiers::OCL_None:
3788 case Qualifiers::OCL_ExplicitNone:
3789 case Qualifiers::OCL_Weak:
3793 RValue RV = EmitAnyExpr(E->getRHS());
3794 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
3795 EmitStoreThroughLValue(RV, LV);
3800 return EmitComplexAssignmentLValue(E);
3803 return EmitAggExprToLValue(E);
3805 llvm_unreachable("bad evaluation kind");
3808 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
3809 RValue RV = EmitCallExpr(E);
3812 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
3813 AlignmentSource::Decl);
3815 assert(E->getCallReturnType(getContext())->isReferenceType() &&
3816 "Can't have a scalar return unless the return type is a "
3819 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
3822 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
3823 // FIXME: This shouldn't require another copy.
3824 return EmitAggExprToLValue(E);
3827 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
3828 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
3829 && "binding l-value to type which needs a temporary");
3830 AggValueSlot Slot = CreateAggTemp(E->getType());
3831 EmitCXXConstructExpr(E, Slot);
3832 return MakeAddrLValue(Slot.getAddress(), E->getType(),
3833 AlignmentSource::Decl);
3837 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
3838 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType());
3841 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
3842 return Builder.CreateElementBitCast(CGM.GetAddrOfUuidDescriptor(E),
3843 ConvertType(E->getType()));
3846 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
3847 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(),
3848 AlignmentSource::Decl);
3852 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
3853 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
3854 Slot.setExternallyDestructed();
3855 EmitAggExpr(E->getSubExpr(), Slot);
3856 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress());
3857 return MakeAddrLValue(Slot.getAddress(), E->getType(),
3858 AlignmentSource::Decl);
3862 CodeGenFunction::EmitLambdaLValue(const LambdaExpr *E) {
3863 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
3864 EmitLambdaExpr(E, Slot);
3865 return MakeAddrLValue(Slot.getAddress(), E->getType(),
3866 AlignmentSource::Decl);
3869 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
3870 RValue RV = EmitObjCMessageExpr(E);
3873 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
3874 AlignmentSource::Decl);
3876 assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
3877 "Can't have a scalar return unless the return type is a "
3880 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
3883 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
3885 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector());
3886 return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl);
3889 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
3890 const ObjCIvarDecl *Ivar) {
3891 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
3894 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
3895 llvm::Value *BaseValue,
3896 const ObjCIvarDecl *Ivar,
3897 unsigned CVRQualifiers) {
3898 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
3899 Ivar, CVRQualifiers);
3902 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
3903 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
3904 llvm::Value *BaseValue = nullptr;
3905 const Expr *BaseExpr = E->getBase();
3906 Qualifiers BaseQuals;
3909 BaseValue = EmitScalarExpr(BaseExpr);
3910 ObjectTy = BaseExpr->getType()->getPointeeType();
3911 BaseQuals = ObjectTy.getQualifiers();
3913 LValue BaseLV = EmitLValue(BaseExpr);
3914 BaseValue = BaseLV.getPointer();
3915 ObjectTy = BaseExpr->getType();
3916 BaseQuals = ObjectTy.getQualifiers();
3920 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
3921 BaseQuals.getCVRQualifiers());
3922 setObjCGCLValueClass(getContext(), E, LV);
3926 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
3927 // Can only get l-value for message expression returning aggregate type
3928 RValue RV = EmitAnyExprToTemp(E);
3929 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
3930 AlignmentSource::Decl);
3933 RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee,
3934 const CallExpr *E, ReturnValueSlot ReturnValue,
3935 CGCalleeInfo CalleeInfo, llvm::Value *Chain) {
3936 // Get the actual function type. The callee type will always be a pointer to
3937 // function type or a block pointer type.
3938 assert(CalleeType->isFunctionPointerType() &&
3939 "Call must have function pointer type!");
3941 // Preserve the non-canonical function type because things like exception
3942 // specifications disappear in the canonical type. That information is useful
3943 // to drive the generation of more accurate code for this call later on.
3944 const FunctionProtoType *NonCanonicalFTP = CalleeType->getAs<PointerType>()
3946 ->getAs<FunctionProtoType>();
3948 const Decl *TargetDecl = CalleeInfo.getCalleeDecl();
3950 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl))
3951 // We can only guarantee that a function is called from the correct
3952 // context/function based on the appropriate target attributes,
3953 // so only check in the case where we have both always_inline and target
3954 // since otherwise we could be making a conditional call after a check for
3955 // the proper cpu features (and it won't cause code generation issues due to
3956 // function based code generation).
3957 if (TargetDecl->hasAttr<AlwaysInlineAttr>() &&
3958 TargetDecl->hasAttr<TargetAttr>())
3959 checkTargetFeatures(E, FD);
3961 CalleeType = getContext().getCanonicalType(CalleeType);
3963 const auto *FnType =
3964 cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
3966 if (getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function) &&
3967 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
3968 if (llvm::Constant *PrefixSig =
3969 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
3970 SanitizerScope SanScope(this);
3971 llvm::Constant *FTRTTIConst =
3972 CGM.GetAddrOfRTTIDescriptor(QualType(FnType, 0), /*ForEH=*/true);
3973 llvm::Type *PrefixStructTyElems[] = {
3974 PrefixSig->getType(),
3975 FTRTTIConst->getType()
3977 llvm::StructType *PrefixStructTy = llvm::StructType::get(
3978 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
3980 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
3981 Callee, llvm::PointerType::getUnqual(PrefixStructTy));
3982 llvm::Value *CalleeSigPtr =
3983 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 0);
3984 llvm::Value *CalleeSig =
3985 Builder.CreateAlignedLoad(CalleeSigPtr, getIntAlign());
3986 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
3988 llvm::BasicBlock *Cont = createBasicBlock("cont");
3989 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
3990 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
3992 EmitBlock(TypeCheck);
3993 llvm::Value *CalleeRTTIPtr =
3994 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 1);
3995 llvm::Value *CalleeRTTI =
3996 Builder.CreateAlignedLoad(CalleeRTTIPtr, getPointerAlign());
3997 llvm::Value *CalleeRTTIMatch =
3998 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
3999 llvm::Constant *StaticData[] = {
4000 EmitCheckSourceLocation(E->getLocStart()),
4001 EmitCheckTypeDescriptor(CalleeType)
4003 EmitCheck(std::make_pair(CalleeRTTIMatch, SanitizerKind::Function),
4004 "function_type_mismatch", StaticData, Callee);
4006 Builder.CreateBr(Cont);
4011 // If we are checking indirect calls and this call is indirect, check that the
4012 // function pointer is a member of the bit set for the function type.
4013 if (SanOpts.has(SanitizerKind::CFIICall) &&
4014 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4015 SanitizerScope SanScope(this);
4016 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
4018 llvm::Metadata *MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
4019 llvm::Value *BitSetName = llvm::MetadataAsValue::get(getLLVMContext(), MD);
4021 llvm::Value *CastedCallee = Builder.CreateBitCast(Callee, Int8PtrTy);
4022 llvm::Value *BitSetTest =
4023 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::bitset_test),
4024 {CastedCallee, BitSetName});
4026 auto TypeId = CGM.CreateCfiIdForTypeMetadata(MD);
4027 llvm::Constant *StaticData[] = {
4028 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall),
4029 EmitCheckSourceLocation(E->getLocStart()),
4030 EmitCheckTypeDescriptor(QualType(FnType, 0)),
4032 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && TypeId) {
4033 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, BitSetTest, TypeId,
4034 CastedCallee, StaticData);
4036 EmitCheck(std::make_pair(BitSetTest, SanitizerKind::CFIICall),
4037 "cfi_check_fail", StaticData,
4038 {CastedCallee, llvm::UndefValue::get(IntPtrTy)});
4044 Args.add(RValue::get(Builder.CreateBitCast(Chain, CGM.VoidPtrTy)),
4045 CGM.getContext().VoidPtrTy);
4046 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(),
4047 E->getDirectCallee(), /*ParamsToSkip*/ 0);
4049 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall(
4050 Args, FnType, /*isChainCall=*/Chain);
4053 // If the expression that denotes the called function has a type
4054 // that does not include a prototype, [the default argument
4055 // promotions are performed]. If the number of arguments does not
4056 // equal the number of parameters, the behavior is undefined. If
4057 // the function is defined with a type that includes a prototype,
4058 // and either the prototype ends with an ellipsis (, ...) or the
4059 // types of the arguments after promotion are not compatible with
4060 // the types of the parameters, the behavior is undefined. If the
4061 // function is defined with a type that does not include a
4062 // prototype, and the types of the arguments after promotion are
4063 // not compatible with those of the parameters after promotion,
4064 // the behavior is undefined [except in some trivial cases].
4065 // That is, in the general case, we should assume that a call
4066 // through an unprototyped function type works like a *non-variadic*
4067 // call. The way we make this work is to cast to the exact type
4068 // of the promoted arguments.
4070 // Chain calls use this same code path to add the invisible chain parameter
4071 // to the function type.
4072 if (isa<FunctionNoProtoType>(FnType) || Chain) {
4073 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
4074 CalleeTy = CalleeTy->getPointerTo();
4075 Callee = Builder.CreateBitCast(Callee, CalleeTy, "callee.knr.cast");
4078 return EmitCall(FnInfo, Callee, ReturnValue, Args,
4079 CGCalleeInfo(NonCanonicalFTP, TargetDecl));
4082 LValue CodeGenFunction::
4083 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
4084 Address BaseAddr = Address::invalid();
4085 if (E->getOpcode() == BO_PtrMemI) {
4086 BaseAddr = EmitPointerWithAlignment(E->getLHS());
4088 BaseAddr = EmitLValue(E->getLHS()).getAddress();
4091 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
4093 const MemberPointerType *MPT
4094 = E->getRHS()->getType()->getAs<MemberPointerType>();
4096 AlignmentSource AlignSource;
4097 Address MemberAddr =
4098 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT,
4101 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), AlignSource);
4104 /// Given the address of a temporary variable, produce an r-value of
4106 RValue CodeGenFunction::convertTempToRValue(Address addr,
4108 SourceLocation loc) {
4109 LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl);
4110 switch (getEvaluationKind(type)) {
4112 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
4114 return lvalue.asAggregateRValue();
4116 return RValue::get(EmitLoadOfScalar(lvalue, loc));
4118 llvm_unreachable("bad evaluation kind");
4121 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
4122 assert(Val->getType()->isFPOrFPVectorTy());
4123 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
4126 llvm::MDBuilder MDHelper(getLLVMContext());
4127 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
4129 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
4133 struct LValueOrRValue {
4139 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
4140 const PseudoObjectExpr *E,
4142 AggValueSlot slot) {
4143 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
4145 // Find the result expression, if any.
4146 const Expr *resultExpr = E->getResultExpr();
4147 LValueOrRValue result;
4149 for (PseudoObjectExpr::const_semantics_iterator
4150 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
4151 const Expr *semantic = *i;
4153 // If this semantic expression is an opaque value, bind it
4154 // to the result of its source expression.
4155 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
4157 // If this is the result expression, we may need to evaluate
4158 // directly into the slot.
4159 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
4161 if (ov == resultExpr && ov->isRValue() && !forLValue &&
4162 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
4163 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
4165 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(),
4166 AlignmentSource::Decl);
4167 opaqueData = OVMA::bind(CGF, ov, LV);
4168 result.RV = slot.asRValue();
4170 // Otherwise, emit as normal.
4172 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
4174 // If this is the result, also evaluate the result now.
4175 if (ov == resultExpr) {
4177 result.LV = CGF.EmitLValue(ov);
4179 result.RV = CGF.EmitAnyExpr(ov, slot);
4183 opaques.push_back(opaqueData);
4185 // Otherwise, if the expression is the result, evaluate it
4186 // and remember the result.
4187 } else if (semantic == resultExpr) {
4189 result.LV = CGF.EmitLValue(semantic);
4191 result.RV = CGF.EmitAnyExpr(semantic, slot);
4193 // Otherwise, evaluate the expression in an ignored context.
4195 CGF.EmitIgnoredExpr(semantic);
4199 // Unbind all the opaques now.
4200 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
4201 opaques[i].unbind(CGF);
4206 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
4207 AggValueSlot slot) {
4208 return emitPseudoObjectExpr(*this, E, false, slot).RV;
4211 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
4212 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;