1 //===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This contains code to emit Expr nodes as LLVM code.
12 //===----------------------------------------------------------------------===//
16 #include "CGCleanup.h"
17 #include "CGDebugInfo.h"
18 #include "CGObjCRuntime.h"
19 #include "CGOpenMPRuntime.h"
20 #include "CGRecordLayout.h"
21 #include "CodeGenFunction.h"
22 #include "CodeGenModule.h"
23 #include "ConstantEmitter.h"
24 #include "TargetInfo.h"
25 #include "clang/AST/ASTContext.h"
26 #include "clang/AST/Attr.h"
27 #include "clang/AST/DeclObjC.h"
28 #include "clang/AST/NSAPI.h"
29 #include "clang/Basic/CodeGenOptions.h"
30 #include "llvm/ADT/Hashing.h"
31 #include "llvm/ADT/StringExtras.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/Intrinsics.h"
34 #include "llvm/IR/LLVMContext.h"
35 #include "llvm/IR/MDBuilder.h"
36 #include "llvm/Support/ConvertUTF.h"
37 #include "llvm/Support/MathExtras.h"
38 #include "llvm/Support/Path.h"
39 #include "llvm/Transforms/Utils/SanitizerStats.h"
43 using namespace clang;
44 using namespace CodeGen;
46 //===--------------------------------------------------------------------===//
47 // Miscellaneous Helper Methods
48 //===--------------------------------------------------------------------===//
50 llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) {
51 unsigned addressSpace =
52 cast<llvm::PointerType>(value->getType())->getAddressSpace();
54 llvm::PointerType *destType = Int8PtrTy;
56 destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace);
58 if (value->getType() == destType) return value;
59 return Builder.CreateBitCast(value, destType);
62 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
64 Address CodeGenFunction::CreateTempAllocaWithoutCast(llvm::Type *Ty,
67 llvm::Value *ArraySize) {
68 auto Alloca = CreateTempAlloca(Ty, Name, ArraySize);
69 Alloca->setAlignment(Align.getQuantity());
70 return Address(Alloca, Align);
73 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
74 /// block. The alloca is casted to default address space if necessary.
75 Address CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, CharUnits Align,
77 llvm::Value *ArraySize,
78 Address *AllocaAddr) {
79 auto Alloca = CreateTempAllocaWithoutCast(Ty, Align, Name, ArraySize);
82 llvm::Value *V = Alloca.getPointer();
83 // Alloca always returns a pointer in alloca address space, which may
84 // be different from the type defined by the language. For example,
85 // in C++ the auto variables are in the default address space. Therefore
86 // cast alloca to the default address space when necessary.
87 if (getASTAllocaAddressSpace() != LangAS::Default) {
88 auto DestAddrSpace = getContext().getTargetAddressSpace(LangAS::Default);
89 llvm::IRBuilderBase::InsertPointGuard IPG(Builder);
90 // When ArraySize is nullptr, alloca is inserted at AllocaInsertPt,
91 // otherwise alloca is inserted at the current insertion point of the
94 Builder.SetInsertPoint(AllocaInsertPt);
95 V = getTargetHooks().performAddrSpaceCast(
96 *this, V, getASTAllocaAddressSpace(), LangAS::Default,
97 Ty->getPointerTo(DestAddrSpace), /*non-null*/ true);
100 return Address(V, Align);
103 /// CreateTempAlloca - This creates an alloca and inserts it into the entry
104 /// block if \p ArraySize is nullptr, otherwise inserts it at the current
105 /// insertion point of the builder.
106 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty,
108 llvm::Value *ArraySize) {
110 return Builder.CreateAlloca(Ty, ArraySize, Name);
111 return new llvm::AllocaInst(Ty, CGM.getDataLayout().getAllocaAddrSpace(),
112 ArraySize, Name, AllocaInsertPt);
115 /// CreateDefaultAlignTempAlloca - This creates an alloca with the
116 /// default alignment of the corresponding LLVM type, which is *not*
117 /// guaranteed to be related in any way to the expected alignment of
118 /// an AST type that might have been lowered to Ty.
119 Address CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty,
122 CharUnits::fromQuantity(CGM.getDataLayout().getABITypeAlignment(Ty));
123 return CreateTempAlloca(Ty, Align, Name);
126 void CodeGenFunction::InitTempAlloca(Address Var, llvm::Value *Init) {
127 assert(isa<llvm::AllocaInst>(Var.getPointer()));
128 auto *Store = new llvm::StoreInst(Init, Var.getPointer());
129 Store->setAlignment(Var.getAlignment().getQuantity());
130 llvm::BasicBlock *Block = AllocaInsertPt->getParent();
131 Block->getInstList().insertAfter(AllocaInsertPt->getIterator(), Store);
134 Address CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) {
135 CharUnits Align = getContext().getTypeAlignInChars(Ty);
136 return CreateTempAlloca(ConvertType(Ty), Align, Name);
139 Address CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name,
141 // FIXME: Should we prefer the preferred type alignment here?
142 return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name, Alloca);
145 Address CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align,
146 const Twine &Name, Address *Alloca) {
147 return CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name,
148 /*ArraySize=*/nullptr, Alloca);
151 Address CodeGenFunction::CreateMemTempWithoutCast(QualType Ty, CharUnits Align,
153 return CreateTempAllocaWithoutCast(ConvertTypeForMem(Ty), Align, Name);
156 Address CodeGenFunction::CreateMemTempWithoutCast(QualType Ty,
158 return CreateMemTempWithoutCast(Ty, getContext().getTypeAlignInChars(Ty),
162 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
163 /// expression and compare the result against zero, returning an Int1Ty value.
164 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
165 PGO.setCurrentStmt(E);
166 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
167 llvm::Value *MemPtr = EmitScalarExpr(E);
168 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
171 QualType BoolTy = getContext().BoolTy;
172 SourceLocation Loc = E->getExprLoc();
173 if (!E->getType()->isAnyComplexType())
174 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc);
176 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy,
180 /// EmitIgnoredExpr - Emit code to compute the specified expression,
181 /// ignoring the result.
182 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
184 return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true);
186 // Just emit it as an l-value and drop the result.
190 /// EmitAnyExpr - Emit code to compute the specified expression which
191 /// can have any type. The result is returned as an RValue struct.
192 /// If this is an aggregate expression, AggSlot indicates where the
193 /// result should be returned.
194 RValue CodeGenFunction::EmitAnyExpr(const Expr *E,
195 AggValueSlot aggSlot,
197 switch (getEvaluationKind(E->getType())) {
199 return RValue::get(EmitScalarExpr(E, ignoreResult));
201 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult));
203 if (!ignoreResult && aggSlot.isIgnored())
204 aggSlot = CreateAggTemp(E->getType(), "agg-temp");
205 EmitAggExpr(E, aggSlot);
206 return aggSlot.asRValue();
208 llvm_unreachable("bad evaluation kind");
211 /// EmitAnyExprToTemp - Similar to EmitAnyExpr(), however, the result will
212 /// always be accessible even if no aggregate location is provided.
213 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
214 AggValueSlot AggSlot = AggValueSlot::ignored();
216 if (hasAggregateEvaluationKind(E->getType()))
217 AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
218 return EmitAnyExpr(E, AggSlot);
221 /// EmitAnyExprToMem - Evaluate an expression into a given memory
223 void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
227 // FIXME: This function should take an LValue as an argument.
228 switch (getEvaluationKind(E->getType())) {
230 EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()),
234 case TEK_Aggregate: {
235 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals,
236 AggValueSlot::IsDestructed_t(IsInit),
237 AggValueSlot::DoesNotNeedGCBarriers,
238 AggValueSlot::IsAliased_t(!IsInit),
239 AggValueSlot::MayOverlap));
244 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
245 LValue LV = MakeAddrLValue(Location, E->getType());
246 EmitStoreThroughLValue(RV, LV);
250 llvm_unreachable("bad evaluation kind");
254 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
255 const Expr *E, Address ReferenceTemporary) {
256 // Objective-C++ ARC:
257 // If we are binding a reference to a temporary that has ownership, we
258 // need to perform retain/release operations on the temporary.
260 // FIXME: This should be looking at E, not M.
261 if (auto Lifetime = M->getType().getObjCLifetime()) {
263 case Qualifiers::OCL_None:
264 case Qualifiers::OCL_ExplicitNone:
265 // Carry on to normal cleanup handling.
268 case Qualifiers::OCL_Autoreleasing:
269 // Nothing to do; cleaned up by an autorelease pool.
272 case Qualifiers::OCL_Strong:
273 case Qualifiers::OCL_Weak:
274 switch (StorageDuration Duration = M->getStorageDuration()) {
276 // Note: we intentionally do not register a cleanup to release
277 // the object on program termination.
281 // FIXME: We should probably register a cleanup in this case.
285 case SD_FullExpression:
286 CodeGenFunction::Destroyer *Destroy;
287 CleanupKind CleanupKind;
288 if (Lifetime == Qualifiers::OCL_Strong) {
289 const ValueDecl *VD = M->getExtendingDecl();
291 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>();
292 CleanupKind = CGF.getARCCleanupKind();
293 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise
294 : &CodeGenFunction::destroyARCStrongImprecise;
296 // __weak objects always get EH cleanups; otherwise, exceptions
297 // could cause really nasty crashes instead of mere leaks.
298 CleanupKind = NormalAndEHCleanup;
299 Destroy = &CodeGenFunction::destroyARCWeak;
301 if (Duration == SD_FullExpression)
302 CGF.pushDestroy(CleanupKind, ReferenceTemporary,
303 M->getType(), *Destroy,
304 CleanupKind & EHCleanup);
306 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary,
308 *Destroy, CleanupKind & EHCleanup);
312 llvm_unreachable("temporary cannot have dynamic storage duration");
314 llvm_unreachable("unknown storage duration");
318 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
319 if (const RecordType *RT =
320 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
321 // Get the destructor for the reference temporary.
322 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
323 if (!ClassDecl->hasTrivialDestructor())
324 ReferenceTemporaryDtor = ClassDecl->getDestructor();
327 if (!ReferenceTemporaryDtor)
330 // Call the destructor for the temporary.
331 switch (M->getStorageDuration()) {
334 llvm::Constant *CleanupFn;
335 llvm::Constant *CleanupArg;
336 if (E->getType()->isArrayType()) {
337 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
338 ReferenceTemporary, E->getType(),
339 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
340 dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
341 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
343 CleanupFn = CGF.CGM.getAddrOfCXXStructor(ReferenceTemporaryDtor,
344 StructorType::Complete);
345 CleanupArg = cast<llvm::Constant>(ReferenceTemporary.getPointer());
347 CGF.CGM.getCXXABI().registerGlobalDtor(
348 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
352 case SD_FullExpression:
353 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
354 CodeGenFunction::destroyCXXObject,
355 CGF.getLangOpts().Exceptions);
359 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
360 ReferenceTemporary, E->getType(),
361 CodeGenFunction::destroyCXXObject,
362 CGF.getLangOpts().Exceptions);
366 llvm_unreachable("temporary cannot have dynamic storage duration");
370 static Address createReferenceTemporary(CodeGenFunction &CGF,
371 const MaterializeTemporaryExpr *M,
373 Address *Alloca = nullptr) {
374 auto &TCG = CGF.getTargetHooks();
375 switch (M->getStorageDuration()) {
376 case SD_FullExpression:
378 // If we have a constant temporary array or record try to promote it into a
379 // constant global under the same rules a normal constant would've been
380 // promoted. This is easier on the optimizer and generally emits fewer
382 QualType Ty = Inner->getType();
383 if (CGF.CGM.getCodeGenOpts().MergeAllConstants &&
384 (Ty->isArrayType() || Ty->isRecordType()) &&
385 CGF.CGM.isTypeConstant(Ty, true))
386 if (auto Init = ConstantEmitter(CGF).tryEmitAbstract(Inner, Ty)) {
387 if (auto AddrSpace = CGF.getTarget().getConstantAddressSpace()) {
388 auto AS = AddrSpace.getValue();
389 auto *GV = new llvm::GlobalVariable(
390 CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true,
391 llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp", nullptr,
392 llvm::GlobalValue::NotThreadLocal,
393 CGF.getContext().getTargetAddressSpace(AS));
394 CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty);
395 GV->setAlignment(alignment.getQuantity());
396 llvm::Constant *C = GV;
397 if (AS != LangAS::Default)
398 C = TCG.performAddrSpaceCast(
399 CGF.CGM, GV, AS, LangAS::Default,
400 GV->getValueType()->getPointerTo(
401 CGF.getContext().getTargetAddressSpace(LangAS::Default)));
402 // FIXME: Should we put the new global into a COMDAT?
403 return Address(C, alignment);
406 return CGF.CreateMemTemp(Ty, "ref.tmp", Alloca);
410 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner);
413 llvm_unreachable("temporary can't have dynamic storage duration");
415 llvm_unreachable("unknown storage duration");
418 LValue CodeGenFunction::
419 EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
420 const Expr *E = M->GetTemporaryExpr();
422 assert((!M->getExtendingDecl() || !isa<VarDecl>(M->getExtendingDecl()) ||
423 !cast<VarDecl>(M->getExtendingDecl())->isARCPseudoStrong()) &&
424 "Reference should never be pseudo-strong!");
426 // FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so
427 // as that will cause the lifetime adjustment to be lost for ARC
428 auto ownership = M->getType().getObjCLifetime();
429 if (ownership != Qualifiers::OCL_None &&
430 ownership != Qualifiers::OCL_ExplicitNone) {
431 Address Object = createReferenceTemporary(*this, M, E);
432 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
433 Object = Address(llvm::ConstantExpr::getBitCast(Var,
434 ConvertTypeForMem(E->getType())
435 ->getPointerTo(Object.getAddressSpace())),
436 Object.getAlignment());
438 // createReferenceTemporary will promote the temporary to a global with a
439 // constant initializer if it can. It can only do this to a value of
440 // ARC-manageable type if the value is global and therefore "immune" to
441 // ref-counting operations. Therefore we have no need to emit either a
442 // dynamic initialization or a cleanup and we can just return the address
444 if (Var->hasInitializer())
445 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl);
447 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
449 LValue RefTempDst = MakeAddrLValue(Object, M->getType(),
450 AlignmentSource::Decl);
452 switch (getEvaluationKind(E->getType())) {
453 default: llvm_unreachable("expected scalar or aggregate expression");
455 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false);
457 case TEK_Aggregate: {
458 EmitAggExpr(E, AggValueSlot::forAddr(Object,
459 E->getType().getQualifiers(),
460 AggValueSlot::IsDestructed,
461 AggValueSlot::DoesNotNeedGCBarriers,
462 AggValueSlot::IsNotAliased,
463 AggValueSlot::DoesNotOverlap));
468 pushTemporaryCleanup(*this, M, E, Object);
472 SmallVector<const Expr *, 2> CommaLHSs;
473 SmallVector<SubobjectAdjustment, 2> Adjustments;
474 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
476 for (const auto &Ignored : CommaLHSs)
477 EmitIgnoredExpr(Ignored);
479 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) {
480 if (opaque->getType()->isRecordType()) {
481 assert(Adjustments.empty());
482 return EmitOpaqueValueLValue(opaque);
486 // Create and initialize the reference temporary.
487 Address Alloca = Address::invalid();
488 Address Object = createReferenceTemporary(*this, M, E, &Alloca);
489 if (auto *Var = dyn_cast<llvm::GlobalVariable>(
490 Object.getPointer()->stripPointerCasts())) {
491 Object = Address(llvm::ConstantExpr::getBitCast(
492 cast<llvm::Constant>(Object.getPointer()),
493 ConvertTypeForMem(E->getType())->getPointerTo()),
494 Object.getAlignment());
495 // If the temporary is a global and has a constant initializer or is a
496 // constant temporary that we promoted to a global, we may have already
498 if (!Var->hasInitializer()) {
499 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
500 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
503 switch (M->getStorageDuration()) {
505 if (auto *Size = EmitLifetimeStart(
506 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
507 Alloca.getPointer())) {
508 pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker,
513 case SD_FullExpression: {
514 if (!ShouldEmitLifetimeMarkers)
517 // Avoid creating a conditional cleanup just to hold an llvm.lifetime.end
518 // marker. Instead, start the lifetime of a conditional temporary earlier
519 // so that it's unconditional. Don't do this in ASan's use-after-scope
520 // mode so that it gets the more precise lifetime marks. If the type has
521 // a non-trivial destructor, we'll have a cleanup block for it anyway,
522 // so this typically doesn't help; skip it in that case.
523 ConditionalEvaluation *OldConditional = nullptr;
524 CGBuilderTy::InsertPoint OldIP;
525 if (isInConditionalBranch() && !E->getType().isDestructedType() &&
526 !CGM.getCodeGenOpts().SanitizeAddressUseAfterScope) {
527 OldConditional = OutermostConditional;
528 OutermostConditional = nullptr;
530 OldIP = Builder.saveIP();
531 llvm::BasicBlock *Block = OldConditional->getStartingBlock();
532 Builder.restoreIP(CGBuilderTy::InsertPoint(
533 Block, llvm::BasicBlock::iterator(Block->back())));
536 if (auto *Size = EmitLifetimeStart(
537 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
538 Alloca.getPointer())) {
539 pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca,
543 if (OldConditional) {
544 OutermostConditional = OldConditional;
545 Builder.restoreIP(OldIP);
553 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
555 pushTemporaryCleanup(*this, M, E, Object);
557 // Perform derived-to-base casts and/or field accesses, to get from the
558 // temporary object we created (and, potentially, for which we extended
559 // the lifetime) to the subobject we're binding the reference to.
560 for (unsigned I = Adjustments.size(); I != 0; --I) {
561 SubobjectAdjustment &Adjustment = Adjustments[I-1];
562 switch (Adjustment.Kind) {
563 case SubobjectAdjustment::DerivedToBaseAdjustment:
565 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass,
566 Adjustment.DerivedToBase.BasePath->path_begin(),
567 Adjustment.DerivedToBase.BasePath->path_end(),
568 /*NullCheckValue=*/ false, E->getExprLoc());
571 case SubobjectAdjustment::FieldAdjustment: {
572 LValue LV = MakeAddrLValue(Object, E->getType(), AlignmentSource::Decl);
573 LV = EmitLValueForField(LV, Adjustment.Field);
574 assert(LV.isSimple() &&
575 "materialized temporary field is not a simple lvalue");
576 Object = LV.getAddress();
580 case SubobjectAdjustment::MemberPointerAdjustment: {
581 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS);
582 Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr,
589 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl);
593 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) {
594 // Emit the expression as an lvalue.
595 LValue LV = EmitLValue(E);
596 assert(LV.isSimple());
597 llvm::Value *Value = LV.getPointer();
599 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) {
600 // C++11 [dcl.ref]p5 (as amended by core issue 453):
601 // If a glvalue to which a reference is directly bound designates neither
602 // an existing object or function of an appropriate type nor a region of
603 // storage of suitable size and alignment to contain an object of the
604 // reference's type, the behavior is undefined.
605 QualType Ty = E->getType();
606 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty);
609 return RValue::get(Value);
613 /// getAccessedFieldNo - Given an encoded value and a result number, return the
614 /// input field number being accessed.
615 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
616 const llvm::Constant *Elts) {
617 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx))
621 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h.
622 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low,
624 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL);
625 llvm::Value *K47 = Builder.getInt64(47);
626 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul);
627 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0);
628 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul);
629 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0);
630 return Builder.CreateMul(B1, KMul);
633 bool CodeGenFunction::isNullPointerAllowed(TypeCheckKind TCK) {
634 return TCK == TCK_DowncastPointer || TCK == TCK_Upcast ||
635 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation;
638 bool CodeGenFunction::isVptrCheckRequired(TypeCheckKind TCK, QualType Ty) {
639 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
640 return (RD && RD->hasDefinition() && RD->isDynamicClass()) &&
641 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall ||
642 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference ||
643 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation);
646 bool CodeGenFunction::sanitizePerformTypeCheck() const {
647 return SanOpts.has(SanitizerKind::Null) |
648 SanOpts.has(SanitizerKind::Alignment) |
649 SanOpts.has(SanitizerKind::ObjectSize) |
650 SanOpts.has(SanitizerKind::Vptr);
653 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
654 llvm::Value *Ptr, QualType Ty,
656 SanitizerSet SkippedChecks) {
657 if (!sanitizePerformTypeCheck())
660 // Don't check pointers outside the default address space. The null check
661 // isn't correct, the object-size check isn't supported by LLVM, and we can't
662 // communicate the addresses to the runtime handler for the vptr check.
663 if (Ptr->getType()->getPointerAddressSpace())
666 // Don't check pointers to volatile data. The behavior here is implementation-
668 if (Ty.isVolatileQualified())
671 SanitizerScope SanScope(this);
673 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks;
674 llvm::BasicBlock *Done = nullptr;
676 // Quickly determine whether we have a pointer to an alloca. It's possible
677 // to skip null checks, and some alignment checks, for these pointers. This
678 // can reduce compile-time significantly.
680 dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCastsNoFollowAliases());
682 llvm::Value *True = llvm::ConstantInt::getTrue(getLLVMContext());
683 llvm::Value *IsNonNull = nullptr;
684 bool IsGuaranteedNonNull =
685 SkippedChecks.has(SanitizerKind::Null) || PtrToAlloca;
686 bool AllowNullPointers = isNullPointerAllowed(TCK);
687 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) &&
688 !IsGuaranteedNonNull) {
689 // The glvalue must not be an empty glvalue.
690 IsNonNull = Builder.CreateIsNotNull(Ptr);
692 // The IR builder can constant-fold the null check if the pointer points to
694 IsGuaranteedNonNull = IsNonNull == True;
696 // Skip the null check if the pointer is known to be non-null.
697 if (!IsGuaranteedNonNull) {
698 if (AllowNullPointers) {
699 // When performing pointer casts, it's OK if the value is null.
700 // Skip the remaining checks in that case.
701 Done = createBasicBlock("null");
702 llvm::BasicBlock *Rest = createBasicBlock("not.null");
703 Builder.CreateCondBr(IsNonNull, Rest, Done);
706 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null));
711 if (SanOpts.has(SanitizerKind::ObjectSize) &&
712 !SkippedChecks.has(SanitizerKind::ObjectSize) &&
713 !Ty->isIncompleteType()) {
714 uint64_t Size = getContext().getTypeSizeInChars(Ty).getQuantity();
716 // The glvalue must refer to a large enough storage region.
717 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
719 // FIXME: Get object address space
720 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
721 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
722 llvm::Value *Min = Builder.getFalse();
723 llvm::Value *NullIsUnknown = Builder.getFalse();
724 llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy);
725 llvm::Value *LargeEnough = Builder.CreateICmpUGE(
726 Builder.CreateCall(F, {CastAddr, Min, NullIsUnknown}),
727 llvm::ConstantInt::get(IntPtrTy, Size));
728 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
731 uint64_t AlignVal = 0;
732 llvm::Value *PtrAsInt = nullptr;
734 if (SanOpts.has(SanitizerKind::Alignment) &&
735 !SkippedChecks.has(SanitizerKind::Alignment)) {
736 AlignVal = Alignment.getQuantity();
737 if (!Ty->isIncompleteType() && !AlignVal)
738 AlignVal = getContext().getTypeAlignInChars(Ty).getQuantity();
740 // The glvalue must be suitably aligned.
742 (!PtrToAlloca || PtrToAlloca->getAlignment() < AlignVal)) {
743 PtrAsInt = Builder.CreatePtrToInt(Ptr, IntPtrTy);
744 llvm::Value *Align = Builder.CreateAnd(
745 PtrAsInt, llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
746 llvm::Value *Aligned =
747 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
749 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment));
753 if (Checks.size() > 0) {
754 // Make sure we're not losing information. Alignment needs to be a power of
756 assert(!AlignVal || (uint64_t)1 << llvm::Log2_64(AlignVal) == AlignVal);
757 llvm::Constant *StaticData[] = {
758 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty),
759 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2_64(AlignVal) : 1),
760 llvm::ConstantInt::get(Int8Ty, TCK)};
761 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData,
762 PtrAsInt ? PtrAsInt : Ptr);
765 // If possible, check that the vptr indicates that there is a subobject of
766 // type Ty at offset zero within this object.
768 // C++11 [basic.life]p5,6:
769 // [For storage which does not refer to an object within its lifetime]
770 // The program has undefined behavior if:
771 // -- the [pointer or glvalue] is used to access a non-static data member
772 // or call a non-static member function
773 if (SanOpts.has(SanitizerKind::Vptr) &&
774 !SkippedChecks.has(SanitizerKind::Vptr) && isVptrCheckRequired(TCK, Ty)) {
775 // Ensure that the pointer is non-null before loading it. If there is no
776 // compile-time guarantee, reuse the run-time null check or emit a new one.
777 if (!IsGuaranteedNonNull) {
779 IsNonNull = Builder.CreateIsNotNull(Ptr);
781 Done = createBasicBlock("vptr.null");
782 llvm::BasicBlock *VptrNotNull = createBasicBlock("vptr.not.null");
783 Builder.CreateCondBr(IsNonNull, VptrNotNull, Done);
784 EmitBlock(VptrNotNull);
787 // Compute a hash of the mangled name of the type.
789 // FIXME: This is not guaranteed to be deterministic! Move to a
790 // fingerprinting mechanism once LLVM provides one. For the time
791 // being the implementation happens to be deterministic.
792 SmallString<64> MangledName;
793 llvm::raw_svector_ostream Out(MangledName);
794 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
797 // Blacklist based on the mangled type.
798 if (!CGM.getContext().getSanitizerBlacklist().isBlacklistedType(
799 SanitizerKind::Vptr, Out.str())) {
800 llvm::hash_code TypeHash = hash_value(Out.str());
802 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
803 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
804 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
805 Address VPtrAddr(Builder.CreateBitCast(Ptr, VPtrTy), getPointerAlign());
806 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
807 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
809 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
810 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
812 // Look the hash up in our cache.
813 const int CacheSize = 128;
814 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
815 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
816 "__ubsan_vptr_type_cache");
817 llvm::Value *Slot = Builder.CreateAnd(Hash,
818 llvm::ConstantInt::get(IntPtrTy,
820 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
821 llvm::Value *CacheVal =
822 Builder.CreateAlignedLoad(Builder.CreateInBoundsGEP(Cache, Indices),
825 // If the hash isn't in the cache, call a runtime handler to perform the
826 // hard work of checking whether the vptr is for an object of the right
827 // type. This will either fill in the cache and return, or produce a
829 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash);
830 llvm::Constant *StaticData[] = {
831 EmitCheckSourceLocation(Loc),
832 EmitCheckTypeDescriptor(Ty),
833 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
834 llvm::ConstantInt::get(Int8Ty, TCK)
836 llvm::Value *DynamicData[] = { Ptr, Hash };
837 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr),
838 SanitizerHandler::DynamicTypeCacheMiss, StaticData,
844 Builder.CreateBr(Done);
849 /// Determine whether this expression refers to a flexible array member in a
850 /// struct. We disable array bounds checks for such members.
851 static bool isFlexibleArrayMemberExpr(const Expr *E) {
852 // For compatibility with existing code, we treat arrays of length 0 or
853 // 1 as flexible array members.
854 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
855 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
856 if (CAT->getSize().ugt(1))
858 } else if (!isa<IncompleteArrayType>(AT))
861 E = E->IgnoreParens();
863 // A flexible array member must be the last member in the class.
864 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
865 // FIXME: If the base type of the member expr is not FD->getParent(),
866 // this should not be treated as a flexible array member access.
867 if (const auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
868 RecordDecl::field_iterator FI(
869 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
870 return ++FI == FD->getParent()->field_end();
872 } else if (const auto *IRE = dyn_cast<ObjCIvarRefExpr>(E)) {
873 return IRE->getDecl()->getNextIvar() == nullptr;
879 llvm::Value *CodeGenFunction::LoadPassedObjectSize(const Expr *E,
881 ASTContext &C = getContext();
882 uint64_t EltSize = C.getTypeSizeInChars(EltTy).getQuantity();
886 auto *ArrayDeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts());
890 auto *ParamDecl = dyn_cast<ParmVarDecl>(ArrayDeclRef->getDecl());
894 auto *POSAttr = ParamDecl->getAttr<PassObjectSizeAttr>();
898 // Don't load the size if it's a lower bound.
899 int POSType = POSAttr->getType();
900 if (POSType != 0 && POSType != 1)
903 // Find the implicit size parameter.
904 auto PassedSizeIt = SizeArguments.find(ParamDecl);
905 if (PassedSizeIt == SizeArguments.end())
908 const ImplicitParamDecl *PassedSizeDecl = PassedSizeIt->second;
909 assert(LocalDeclMap.count(PassedSizeDecl) && "Passed size not loadable");
910 Address AddrOfSize = LocalDeclMap.find(PassedSizeDecl)->second;
911 llvm::Value *SizeInBytes = EmitLoadOfScalar(AddrOfSize, /*Volatile=*/false,
912 C.getSizeType(), E->getExprLoc());
913 llvm::Value *SizeOfElement =
914 llvm::ConstantInt::get(SizeInBytes->getType(), EltSize);
915 return Builder.CreateUDiv(SizeInBytes, SizeOfElement);
918 /// If Base is known to point to the start of an array, return the length of
919 /// that array. Return 0 if the length cannot be determined.
920 static llvm::Value *getArrayIndexingBound(
921 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
922 // For the vector indexing extension, the bound is the number of elements.
923 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
924 IndexedType = Base->getType();
925 return CGF.Builder.getInt32(VT->getNumElements());
928 Base = Base->IgnoreParens();
930 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
931 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
932 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
933 IndexedType = CE->getSubExpr()->getType();
934 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
935 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
936 return CGF.Builder.getInt(CAT->getSize());
937 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
938 return CGF.getVLASize(VAT).NumElts;
939 // Ignore pass_object_size here. It's not applicable on decayed pointers.
943 QualType EltTy{Base->getType()->getPointeeOrArrayElementType(), 0};
944 if (llvm::Value *POS = CGF.LoadPassedObjectSize(Base, EltTy)) {
945 IndexedType = Base->getType();
952 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
953 llvm::Value *Index, QualType IndexType,
955 assert(SanOpts.has(SanitizerKind::ArrayBounds) &&
956 "should not be called unless adding bounds checks");
957 SanitizerScope SanScope(this);
959 QualType IndexedType;
960 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
964 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
965 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
966 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
968 llvm::Constant *StaticData[] = {
969 EmitCheckSourceLocation(E->getExprLoc()),
970 EmitCheckTypeDescriptor(IndexedType),
971 EmitCheckTypeDescriptor(IndexType)
973 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
974 : Builder.CreateICmpULE(IndexVal, BoundVal);
975 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds),
976 SanitizerHandler::OutOfBounds, StaticData, Index);
980 CodeGenFunction::ComplexPairTy CodeGenFunction::
981 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
982 bool isInc, bool isPre) {
983 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
985 llvm::Value *NextVal;
986 if (isa<llvm::IntegerType>(InVal.first->getType())) {
987 uint64_t AmountVal = isInc ? 1 : -1;
988 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
990 // Add the inc/dec to the real part.
991 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
993 QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
994 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
997 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
999 // Add the inc/dec to the real part.
1000 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1003 ComplexPairTy IncVal(NextVal, InVal.second);
1005 // Store the updated result through the lvalue.
1006 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
1008 // If this is a postinc, return the value read from memory, otherwise use the
1010 return isPre ? IncVal : InVal;
1013 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E,
1014 CodeGenFunction *CGF) {
1015 // Bind VLAs in the cast type.
1016 if (CGF && E->getType()->isVariablyModifiedType())
1017 CGF->EmitVariablyModifiedType(E->getType());
1019 if (CGDebugInfo *DI = getModuleDebugInfo())
1020 DI->EmitExplicitCastType(E->getType());
1023 //===----------------------------------------------------------------------===//
1024 // LValue Expression Emission
1025 //===----------------------------------------------------------------------===//
1027 /// EmitPointerWithAlignment - Given an expression of pointer type, try to
1028 /// derive a more accurate bound on the alignment of the pointer.
1029 Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
1030 LValueBaseInfo *BaseInfo,
1031 TBAAAccessInfo *TBAAInfo) {
1032 // We allow this with ObjC object pointers because of fragile ABIs.
1033 assert(E->getType()->isPointerType() ||
1034 E->getType()->isObjCObjectPointerType());
1035 E = E->IgnoreParens();
1038 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
1039 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE))
1040 CGM.EmitExplicitCastExprType(ECE, this);
1042 switch (CE->getCastKind()) {
1043 // Non-converting casts (but not C's implicit conversion from void*).
1046 case CK_AddressSpaceConversion:
1047 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) {
1048 if (PtrTy->getPointeeType()->isVoidType())
1051 LValueBaseInfo InnerBaseInfo;
1052 TBAAAccessInfo InnerTBAAInfo;
1053 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(),
1056 if (BaseInfo) *BaseInfo = InnerBaseInfo;
1057 if (TBAAInfo) *TBAAInfo = InnerTBAAInfo;
1059 if (isa<ExplicitCastExpr>(CE)) {
1060 LValueBaseInfo TargetTypeBaseInfo;
1061 TBAAAccessInfo TargetTypeTBAAInfo;
1062 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(),
1063 &TargetTypeBaseInfo,
1064 &TargetTypeTBAAInfo);
1066 *TBAAInfo = CGM.mergeTBAAInfoForCast(*TBAAInfo,
1067 TargetTypeTBAAInfo);
1068 // If the source l-value is opaque, honor the alignment of the
1070 if (InnerBaseInfo.getAlignmentSource() != AlignmentSource::Decl) {
1072 BaseInfo->mergeForCast(TargetTypeBaseInfo);
1073 Addr = Address(Addr.getPointer(), Align);
1077 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast) &&
1078 CE->getCastKind() == CK_BitCast) {
1079 if (auto PT = E->getType()->getAs<PointerType>())
1080 EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr.getPointer(),
1082 CodeGenFunction::CFITCK_UnrelatedCast,
1085 return CE->getCastKind() != CK_AddressSpaceConversion
1086 ? Builder.CreateBitCast(Addr, ConvertType(E->getType()))
1087 : Builder.CreateAddrSpaceCast(Addr,
1088 ConvertType(E->getType()));
1092 // Array-to-pointer decay.
1093 case CK_ArrayToPointerDecay:
1094 return EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo, TBAAInfo);
1096 // Derived-to-base conversions.
1097 case CK_UncheckedDerivedToBase:
1098 case CK_DerivedToBase: {
1099 // TODO: Support accesses to members of base classes in TBAA. For now, we
1100 // conservatively pretend that the complete object is of the base class
1103 *TBAAInfo = CGM.getTBAAAccessInfo(E->getType());
1104 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), BaseInfo);
1105 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl();
1106 return GetAddressOfBaseClass(Addr, Derived,
1107 CE->path_begin(), CE->path_end(),
1108 ShouldNullCheckClassCastValue(CE),
1112 // TODO: Is there any reason to treat base-to-derived conversions
1120 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
1121 if (UO->getOpcode() == UO_AddrOf) {
1122 LValue LV = EmitLValue(UO->getSubExpr());
1123 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
1124 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo();
1125 return LV.getAddress();
1129 // TODO: conditional operators, comma.
1131 // Otherwise, use the alignment of the type.
1132 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(), BaseInfo,
1134 return Address(EmitScalarExpr(E), Align);
1137 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
1138 if (Ty->isVoidType())
1139 return RValue::get(nullptr);
1141 switch (getEvaluationKind(Ty)) {
1144 ConvertType(Ty->castAs<ComplexType>()->getElementType());
1145 llvm::Value *U = llvm::UndefValue::get(EltTy);
1146 return RValue::getComplex(std::make_pair(U, U));
1149 // If this is a use of an undefined aggregate type, the aggregate must have an
1150 // identifiable address. Just because the contents of the value are undefined
1151 // doesn't mean that the address can't be taken and compared.
1152 case TEK_Aggregate: {
1153 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
1154 return RValue::getAggregate(DestPtr);
1158 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
1160 llvm_unreachable("bad evaluation kind");
1163 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
1165 ErrorUnsupported(E, Name);
1166 return GetUndefRValue(E->getType());
1169 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
1171 ErrorUnsupported(E, Name);
1172 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
1173 return MakeAddrLValue(Address(llvm::UndefValue::get(Ty), CharUnits::One()),
1177 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) {
1178 const Expr *Base = Obj;
1179 while (!isa<CXXThisExpr>(Base)) {
1180 // The result of a dynamic_cast can be null.
1181 if (isa<CXXDynamicCastExpr>(Base))
1184 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
1185 Base = CE->getSubExpr();
1186 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) {
1187 Base = PE->getSubExpr();
1188 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) {
1189 if (UO->getOpcode() == UO_Extension)
1190 Base = UO->getSubExpr();
1200 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
1202 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E))
1203 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
1206 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) {
1207 SanitizerSet SkippedChecks;
1208 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
1209 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase());
1211 SkippedChecks.set(SanitizerKind::Alignment, true);
1212 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase()))
1213 SkippedChecks.set(SanitizerKind::Null, true);
1215 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(),
1216 E->getType(), LV.getAlignment(), SkippedChecks);
1221 /// EmitLValue - Emit code to compute a designator that specifies the location
1222 /// of the expression.
1224 /// This can return one of two things: a simple address or a bitfield reference.
1225 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
1226 /// an LLVM pointer type.
1228 /// If this returns a bitfield reference, nothing about the pointee type of the
1229 /// LLVM value is known: For example, it may not be a pointer to an integer.
1231 /// If this returns a normal address, and if the lvalue's C type is fixed size,
1232 /// this method guarantees that the returned pointer type will point to an LLVM
1233 /// type of the same size of the lvalue's type. If the lvalue has a variable
1234 /// length type, this is not possible.
1236 LValue CodeGenFunction::EmitLValue(const Expr *E) {
1237 ApplyDebugLocation DL(*this, E);
1238 switch (E->getStmtClass()) {
1239 default: return EmitUnsupportedLValue(E, "l-value expression");
1241 case Expr::ObjCPropertyRefExprClass:
1242 llvm_unreachable("cannot emit a property reference directly");
1244 case Expr::ObjCSelectorExprClass:
1245 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
1246 case Expr::ObjCIsaExprClass:
1247 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
1248 case Expr::BinaryOperatorClass:
1249 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
1250 case Expr::CompoundAssignOperatorClass: {
1251 QualType Ty = E->getType();
1252 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1253 Ty = AT->getValueType();
1254 if (!Ty->isAnyComplexType())
1255 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1256 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1258 case Expr::CallExprClass:
1259 case Expr::CXXMemberCallExprClass:
1260 case Expr::CXXOperatorCallExprClass:
1261 case Expr::UserDefinedLiteralClass:
1262 return EmitCallExprLValue(cast<CallExpr>(E));
1263 case Expr::VAArgExprClass:
1264 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
1265 case Expr::DeclRefExprClass:
1266 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
1267 case Expr::ConstantExprClass:
1268 return EmitLValue(cast<ConstantExpr>(E)->getSubExpr());
1269 case Expr::ParenExprClass:
1270 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
1271 case Expr::GenericSelectionExprClass:
1272 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
1273 case Expr::PredefinedExprClass:
1274 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
1275 case Expr::StringLiteralClass:
1276 return EmitStringLiteralLValue(cast<StringLiteral>(E));
1277 case Expr::ObjCEncodeExprClass:
1278 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
1279 case Expr::PseudoObjectExprClass:
1280 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
1281 case Expr::InitListExprClass:
1282 return EmitInitListLValue(cast<InitListExpr>(E));
1283 case Expr::CXXTemporaryObjectExprClass:
1284 case Expr::CXXConstructExprClass:
1285 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
1286 case Expr::CXXBindTemporaryExprClass:
1287 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
1288 case Expr::CXXUuidofExprClass:
1289 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
1290 case Expr::LambdaExprClass:
1291 return EmitLambdaLValue(cast<LambdaExpr>(E));
1293 case Expr::ExprWithCleanupsClass: {
1294 const auto *cleanups = cast<ExprWithCleanups>(E);
1295 enterFullExpression(cleanups);
1296 RunCleanupsScope Scope(*this);
1297 LValue LV = EmitLValue(cleanups->getSubExpr());
1298 if (LV.isSimple()) {
1299 // Defend against branches out of gnu statement expressions surrounded by
1301 llvm::Value *V = LV.getPointer();
1302 Scope.ForceCleanup({&V});
1303 return LValue::MakeAddr(Address(V, LV.getAlignment()), LV.getType(),
1304 getContext(), LV.getBaseInfo(), LV.getTBAAInfo());
1306 // FIXME: Is it possible to create an ExprWithCleanups that produces a
1307 // bitfield lvalue or some other non-simple lvalue?
1311 case Expr::CXXDefaultArgExprClass:
1312 return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
1313 case Expr::CXXDefaultInitExprClass: {
1314 CXXDefaultInitExprScope Scope(*this);
1315 return EmitLValue(cast<CXXDefaultInitExpr>(E)->getExpr());
1317 case Expr::CXXTypeidExprClass:
1318 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
1320 case Expr::ObjCMessageExprClass:
1321 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
1322 case Expr::ObjCIvarRefExprClass:
1323 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
1324 case Expr::StmtExprClass:
1325 return EmitStmtExprLValue(cast<StmtExpr>(E));
1326 case Expr::UnaryOperatorClass:
1327 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
1328 case Expr::ArraySubscriptExprClass:
1329 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
1330 case Expr::OMPArraySectionExprClass:
1331 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E));
1332 case Expr::ExtVectorElementExprClass:
1333 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
1334 case Expr::MemberExprClass:
1335 return EmitMemberExpr(cast<MemberExpr>(E));
1336 case Expr::CompoundLiteralExprClass:
1337 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
1338 case Expr::ConditionalOperatorClass:
1339 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
1340 case Expr::BinaryConditionalOperatorClass:
1341 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
1342 case Expr::ChooseExprClass:
1343 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
1344 case Expr::OpaqueValueExprClass:
1345 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
1346 case Expr::SubstNonTypeTemplateParmExprClass:
1347 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
1348 case Expr::ImplicitCastExprClass:
1349 case Expr::CStyleCastExprClass:
1350 case Expr::CXXFunctionalCastExprClass:
1351 case Expr::CXXStaticCastExprClass:
1352 case Expr::CXXDynamicCastExprClass:
1353 case Expr::CXXReinterpretCastExprClass:
1354 case Expr::CXXConstCastExprClass:
1355 case Expr::ObjCBridgedCastExprClass:
1356 return EmitCastLValue(cast<CastExpr>(E));
1358 case Expr::MaterializeTemporaryExprClass:
1359 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
1361 case Expr::CoawaitExprClass:
1362 return EmitCoawaitLValue(cast<CoawaitExpr>(E));
1363 case Expr::CoyieldExprClass:
1364 return EmitCoyieldLValue(cast<CoyieldExpr>(E));
1368 /// Given an object of the given canonical type, can we safely copy a
1369 /// value out of it based on its initializer?
1370 static bool isConstantEmittableObjectType(QualType type) {
1371 assert(type.isCanonical());
1372 assert(!type->isReferenceType());
1374 // Must be const-qualified but non-volatile.
1375 Qualifiers qs = type.getLocalQualifiers();
1376 if (!qs.hasConst() || qs.hasVolatile()) return false;
1378 // Otherwise, all object types satisfy this except C++ classes with
1379 // mutable subobjects or non-trivial copy/destroy behavior.
1380 if (const auto *RT = dyn_cast<RecordType>(type))
1381 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1382 if (RD->hasMutableFields() || !RD->isTrivial())
1388 /// Can we constant-emit a load of a reference to a variable of the
1389 /// given type? This is different from predicates like
1390 /// Decl::isUsableInConstantExpressions because we do want it to apply
1391 /// in situations that don't necessarily satisfy the language's rules
1392 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
1393 /// to do this with const float variables even if those variables
1394 /// aren't marked 'constexpr'.
1395 enum ConstantEmissionKind {
1397 CEK_AsReferenceOnly,
1398 CEK_AsValueOrReference,
1401 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
1402 type = type.getCanonicalType();
1403 if (const auto *ref = dyn_cast<ReferenceType>(type)) {
1404 if (isConstantEmittableObjectType(ref->getPointeeType()))
1405 return CEK_AsValueOrReference;
1406 return CEK_AsReferenceOnly;
1408 if (isConstantEmittableObjectType(type))
1409 return CEK_AsValueOnly;
1413 /// Try to emit a reference to the given value without producing it as
1414 /// an l-value. This is actually more than an optimization: we can't
1415 /// produce an l-value for variables that we never actually captured
1416 /// in a block or lambda, which means const int variables or constexpr
1417 /// literals or similar.
1418 CodeGenFunction::ConstantEmission
1419 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
1420 ValueDecl *value = refExpr->getDecl();
1422 // The value needs to be an enum constant or a constant variable.
1423 ConstantEmissionKind CEK;
1424 if (isa<ParmVarDecl>(value)) {
1426 } else if (auto *var = dyn_cast<VarDecl>(value)) {
1427 CEK = checkVarTypeForConstantEmission(var->getType());
1428 } else if (isa<EnumConstantDecl>(value)) {
1429 CEK = CEK_AsValueOnly;
1433 if (CEK == CEK_None) return ConstantEmission();
1435 Expr::EvalResult result;
1436 bool resultIsReference;
1437 QualType resultType;
1439 // It's best to evaluate all the way as an r-value if that's permitted.
1440 if (CEK != CEK_AsReferenceOnly &&
1441 refExpr->EvaluateAsRValue(result, getContext())) {
1442 resultIsReference = false;
1443 resultType = refExpr->getType();
1445 // Otherwise, try to evaluate as an l-value.
1446 } else if (CEK != CEK_AsValueOnly &&
1447 refExpr->EvaluateAsLValue(result, getContext())) {
1448 resultIsReference = true;
1449 resultType = value->getType();
1453 return ConstantEmission();
1456 // In any case, if the initializer has side-effects, abandon ship.
1457 if (result.HasSideEffects)
1458 return ConstantEmission();
1460 // Emit as a constant.
1461 auto C = ConstantEmitter(*this).emitAbstract(refExpr->getLocation(),
1462 result.Val, resultType);
1464 // Make sure we emit a debug reference to the global variable.
1465 // This should probably fire even for
1466 if (isa<VarDecl>(value)) {
1467 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
1468 EmitDeclRefExprDbgValue(refExpr, result.Val);
1470 assert(isa<EnumConstantDecl>(value));
1471 EmitDeclRefExprDbgValue(refExpr, result.Val);
1474 // If we emitted a reference constant, we need to dereference that.
1475 if (resultIsReference)
1476 return ConstantEmission::forReference(C);
1478 return ConstantEmission::forValue(C);
1481 static DeclRefExpr *tryToConvertMemberExprToDeclRefExpr(CodeGenFunction &CGF,
1482 const MemberExpr *ME) {
1483 if (auto *VD = dyn_cast<VarDecl>(ME->getMemberDecl())) {
1484 // Try to emit static variable member expressions as DREs.
1485 return DeclRefExpr::Create(
1486 CGF.getContext(), NestedNameSpecifierLoc(), SourceLocation(), VD,
1487 /*RefersToEnclosingVariableOrCapture=*/false, ME->getExprLoc(),
1488 ME->getType(), ME->getValueKind());
1493 CodeGenFunction::ConstantEmission
1494 CodeGenFunction::tryEmitAsConstant(const MemberExpr *ME) {
1495 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, ME))
1496 return tryEmitAsConstant(DRE);
1497 return ConstantEmission();
1500 llvm::Value *CodeGenFunction::emitScalarConstant(
1501 const CodeGenFunction::ConstantEmission &Constant, Expr *E) {
1502 assert(Constant && "not a constant");
1503 if (Constant.isReference())
1504 return EmitLoadOfLValue(Constant.getReferenceLValue(*this, E),
1507 return Constant.getValue();
1510 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1511 SourceLocation Loc) {
1512 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
1513 lvalue.getType(), Loc, lvalue.getBaseInfo(),
1514 lvalue.getTBAAInfo(), lvalue.isNontemporal());
1517 static bool hasBooleanRepresentation(QualType Ty) {
1518 if (Ty->isBooleanType())
1521 if (const EnumType *ET = Ty->getAs<EnumType>())
1522 return ET->getDecl()->getIntegerType()->isBooleanType();
1524 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1525 return hasBooleanRepresentation(AT->getValueType());
1530 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1531 llvm::APInt &Min, llvm::APInt &End,
1532 bool StrictEnums, bool IsBool) {
1533 const EnumType *ET = Ty->getAs<EnumType>();
1534 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1535 ET && !ET->getDecl()->isFixed();
1536 if (!IsBool && !IsRegularCPlusPlusEnum)
1540 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1541 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1543 const EnumDecl *ED = ET->getDecl();
1544 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1545 unsigned Bitwidth = LTy->getScalarSizeInBits();
1546 unsigned NumNegativeBits = ED->getNumNegativeBits();
1547 unsigned NumPositiveBits = ED->getNumPositiveBits();
1549 if (NumNegativeBits) {
1550 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1551 assert(NumBits <= Bitwidth);
1552 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1555 assert(NumPositiveBits <= Bitwidth);
1556 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1557 Min = llvm::APInt(Bitwidth, 0);
1563 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1564 llvm::APInt Min, End;
1565 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums,
1566 hasBooleanRepresentation(Ty)))
1569 llvm::MDBuilder MDHelper(getLLVMContext());
1570 return MDHelper.createRange(Min, End);
1573 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
1574 SourceLocation Loc) {
1575 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool);
1576 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum);
1577 if (!HasBoolCheck && !HasEnumCheck)
1580 bool IsBool = hasBooleanRepresentation(Ty) ||
1581 NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
1582 bool NeedsBoolCheck = HasBoolCheck && IsBool;
1583 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>();
1584 if (!NeedsBoolCheck && !NeedsEnumCheck)
1587 // Single-bit booleans don't need to be checked. Special-case this to avoid
1588 // a bit width mismatch when handling bitfield values. This is handled by
1589 // EmitFromMemory for the non-bitfield case.
1591 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1)
1594 llvm::APInt Min, End;
1595 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool))
1598 auto &Ctx = getLLVMContext();
1599 SanitizerScope SanScope(this);
1603 Check = Builder.CreateICmpULE(Value, llvm::ConstantInt::get(Ctx, End));
1605 llvm::Value *Upper =
1606 Builder.CreateICmpSLE(Value, llvm::ConstantInt::get(Ctx, End));
1607 llvm::Value *Lower =
1608 Builder.CreateICmpSGE(Value, llvm::ConstantInt::get(Ctx, Min));
1609 Check = Builder.CreateAnd(Upper, Lower);
1611 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc),
1612 EmitCheckTypeDescriptor(Ty)};
1613 SanitizerMask Kind =
1614 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
1615 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue,
1616 StaticArgs, EmitCheckValue(Value));
1620 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
1623 LValueBaseInfo BaseInfo,
1624 TBAAAccessInfo TBAAInfo,
1625 bool isNontemporal) {
1626 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1627 // For better performance, handle vector loads differently.
1628 if (Ty->isVectorType()) {
1629 const llvm::Type *EltTy = Addr.getElementType();
1631 const auto *VTy = cast<llvm::VectorType>(EltTy);
1633 // Handle vectors of size 3 like size 4 for better performance.
1634 if (VTy->getNumElements() == 3) {
1636 // Bitcast to vec4 type.
1637 llvm::VectorType *vec4Ty =
1638 llvm::VectorType::get(VTy->getElementType(), 4);
1639 Address Cast = Builder.CreateElementBitCast(Addr, vec4Ty, "castToVec4");
1641 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1643 // Shuffle vector to get vec3.
1644 V = Builder.CreateShuffleVector(V, llvm::UndefValue::get(vec4Ty),
1645 {0, 1, 2}, "extractVec");
1646 return EmitFromMemory(V, Ty);
1651 // Atomic operations have to be done on integral types.
1652 LValue AtomicLValue =
1653 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1654 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) {
1655 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal();
1658 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
1659 if (isNontemporal) {
1660 llvm::MDNode *Node = llvm::MDNode::get(
1661 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1662 Load->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1665 CGM.DecorateInstructionWithTBAA(Load, TBAAInfo);
1667 if (EmitScalarRangeCheck(Load, Ty, Loc)) {
1668 // In order to prevent the optimizer from throwing away the check, don't
1669 // attach range metadata to the load.
1670 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1671 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1672 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1674 return EmitFromMemory(Load, Ty);
1677 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1678 // Bool has a different representation in memory than in registers.
1679 if (hasBooleanRepresentation(Ty)) {
1680 // This should really always be an i1, but sometimes it's already
1681 // an i8, and it's awkward to track those cases down.
1682 if (Value->getType()->isIntegerTy(1))
1683 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1684 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1685 "wrong value rep of bool");
1691 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1692 // Bool has a different representation in memory than in registers.
1693 if (hasBooleanRepresentation(Ty)) {
1694 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1695 "wrong value rep of bool");
1696 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1702 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
1703 bool Volatile, QualType Ty,
1704 LValueBaseInfo BaseInfo,
1705 TBAAAccessInfo TBAAInfo,
1706 bool isInit, bool isNontemporal) {
1707 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1708 // Handle vectors differently to get better performance.
1709 if (Ty->isVectorType()) {
1710 llvm::Type *SrcTy = Value->getType();
1711 auto *VecTy = dyn_cast<llvm::VectorType>(SrcTy);
1712 // Handle vec3 special.
1713 if (VecTy && VecTy->getNumElements() == 3) {
1714 // Our source is a vec3, do a shuffle vector to make it a vec4.
1715 llvm::Constant *Mask[] = {Builder.getInt32(0), Builder.getInt32(1),
1716 Builder.getInt32(2),
1717 llvm::UndefValue::get(Builder.getInt32Ty())};
1718 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1719 Value = Builder.CreateShuffleVector(Value, llvm::UndefValue::get(VecTy),
1720 MaskV, "extractVec");
1721 SrcTy = llvm::VectorType::get(VecTy->getElementType(), 4);
1723 if (Addr.getElementType() != SrcTy) {
1724 Addr = Builder.CreateElementBitCast(Addr, SrcTy, "storetmp");
1729 Value = EmitToMemory(Value, Ty);
1731 LValue AtomicLValue =
1732 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1733 if (Ty->isAtomicType() ||
1734 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) {
1735 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit);
1739 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1740 if (isNontemporal) {
1741 llvm::MDNode *Node =
1742 llvm::MDNode::get(Store->getContext(),
1743 llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1744 Store->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1747 CGM.DecorateInstructionWithTBAA(Store, TBAAInfo);
1750 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1752 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
1753 lvalue.getType(), lvalue.getBaseInfo(),
1754 lvalue.getTBAAInfo(), isInit, lvalue.isNontemporal());
1757 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1758 /// method emits the address of the lvalue, then loads the result as an rvalue,
1759 /// returning the rvalue.
1760 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1761 if (LV.isObjCWeak()) {
1762 // load of a __weak object.
1763 Address AddrWeakObj = LV.getAddress();
1764 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1767 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1768 // In MRC mode, we do a load+autorelease.
1769 if (!getLangOpts().ObjCAutoRefCount) {
1770 return RValue::get(EmitARCLoadWeak(LV.getAddress()));
1773 // In ARC mode, we load retained and then consume the value.
1774 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
1775 Object = EmitObjCConsumeObject(LV.getType(), Object);
1776 return RValue::get(Object);
1779 if (LV.isSimple()) {
1780 assert(!LV.getType()->isFunctionType());
1782 // Everything needs a load.
1783 return RValue::get(EmitLoadOfScalar(LV, Loc));
1786 if (LV.isVectorElt()) {
1787 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(),
1788 LV.isVolatileQualified());
1789 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1793 // If this is a reference to a subset of the elements of a vector, either
1794 // shuffle the input or extract/insert them as appropriate.
1795 if (LV.isExtVectorElt())
1796 return EmitLoadOfExtVectorElementLValue(LV);
1798 // Global Register variables always invoke intrinsics
1799 if (LV.isGlobalReg())
1800 return EmitLoadOfGlobalRegLValue(LV);
1802 assert(LV.isBitField() && "Unknown LValue type!");
1803 return EmitLoadOfBitfieldLValue(LV, Loc);
1806 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
1807 SourceLocation Loc) {
1808 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1810 // Get the output type.
1811 llvm::Type *ResLTy = ConvertType(LV.getType());
1813 Address Ptr = LV.getBitFieldAddress();
1814 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load");
1816 if (Info.IsSigned) {
1817 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1818 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1820 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1821 if (Info.Offset + HighBits)
1822 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1825 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1826 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1827 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1831 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1832 EmitScalarRangeCheck(Val, LV.getType(), Loc);
1833 return RValue::get(Val);
1836 // If this is a reference to a subset of the elements of a vector, create an
1837 // appropriate shufflevector.
1838 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1839 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(),
1840 LV.isVolatileQualified());
1842 const llvm::Constant *Elts = LV.getExtVectorElts();
1844 // If the result of the expression is a non-vector type, we must be extracting
1845 // a single element. Just codegen as an extractelement.
1846 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1848 unsigned InIdx = getAccessedFieldNo(0, Elts);
1849 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1850 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1853 // Always use shuffle vector to try to retain the original program structure
1854 unsigned NumResultElts = ExprVT->getNumElements();
1856 SmallVector<llvm::Constant*, 4> Mask;
1857 for (unsigned i = 0; i != NumResultElts; ++i)
1858 Mask.push_back(Builder.getInt32(getAccessedFieldNo(i, Elts)));
1860 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1861 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1863 return RValue::get(Vec);
1866 /// Generates lvalue for partial ext_vector access.
1867 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) {
1868 Address VectorAddress = LV.getExtVectorAddress();
1869 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1870 QualType EQT = ExprVT->getElementType();
1871 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT);
1873 Address CastToPointerElement =
1874 Builder.CreateElementBitCast(VectorAddress, VectorElementTy,
1875 "conv.ptr.element");
1877 const llvm::Constant *Elts = LV.getExtVectorElts();
1878 unsigned ix = getAccessedFieldNo(0, Elts);
1880 Address VectorBasePtrPlusIx =
1881 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix,
1882 getContext().getTypeSizeInChars(EQT),
1885 return VectorBasePtrPlusIx;
1888 /// Load of global gamed gegisters are always calls to intrinsics.
1889 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
1890 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
1891 "Bad type for register variable");
1892 llvm::MDNode *RegName = cast<llvm::MDNode>(
1893 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata());
1895 // We accept integer and pointer types only
1896 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
1897 llvm::Type *Ty = OrigTy;
1898 if (OrigTy->isPointerTy())
1899 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1900 llvm::Type *Types[] = { Ty };
1902 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
1903 llvm::Value *Call = Builder.CreateCall(
1904 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName));
1905 if (OrigTy->isPointerTy())
1906 Call = Builder.CreateIntToPtr(Call, OrigTy);
1907 return RValue::get(Call);
1911 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
1912 /// lvalue, where both are guaranteed to the have the same type, and that type
1914 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
1916 if (!Dst.isSimple()) {
1917 if (Dst.isVectorElt()) {
1918 // Read/modify/write the vector, inserting the new element.
1919 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(),
1920 Dst.isVolatileQualified());
1921 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
1922 Dst.getVectorIdx(), "vecins");
1923 Builder.CreateStore(Vec, Dst.getVectorAddress(),
1924 Dst.isVolatileQualified());
1928 // If this is an update of extended vector elements, insert them as
1930 if (Dst.isExtVectorElt())
1931 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
1933 if (Dst.isGlobalReg())
1934 return EmitStoreThroughGlobalRegLValue(Src, Dst);
1936 assert(Dst.isBitField() && "Unknown LValue type");
1937 return EmitStoreThroughBitfieldLValue(Src, Dst);
1940 // There's special magic for assigning into an ARC-qualified l-value.
1941 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
1943 case Qualifiers::OCL_None:
1944 llvm_unreachable("present but none");
1946 case Qualifiers::OCL_ExplicitNone:
1950 case Qualifiers::OCL_Strong:
1952 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal()));
1955 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
1958 case Qualifiers::OCL_Weak:
1960 // Initialize and then skip the primitive store.
1961 EmitARCInitWeak(Dst.getAddress(), Src.getScalarVal());
1963 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true);
1966 case Qualifiers::OCL_Autoreleasing:
1967 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
1968 Src.getScalarVal()));
1969 // fall into the normal path
1974 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
1975 // load of a __weak object.
1976 Address LvalueDst = Dst.getAddress();
1977 llvm::Value *src = Src.getScalarVal();
1978 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
1982 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
1983 // load of a __strong object.
1984 Address LvalueDst = Dst.getAddress();
1985 llvm::Value *src = Src.getScalarVal();
1986 if (Dst.isObjCIvar()) {
1987 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
1988 llvm::Type *ResultType = IntPtrTy;
1989 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp());
1990 llvm::Value *RHS = dst.getPointer();
1991 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
1993 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType,
1994 "sub.ptr.lhs.cast");
1995 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
1996 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
1998 } else if (Dst.isGlobalObjCRef()) {
1999 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
2000 Dst.isThreadLocalRef());
2003 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
2007 assert(Src.isScalar() && "Can't emit an agg store with this method");
2008 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
2011 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
2012 llvm::Value **Result) {
2013 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
2014 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
2015 Address Ptr = Dst.getBitFieldAddress();
2017 // Get the source value, truncated to the width of the bit-field.
2018 llvm::Value *SrcVal = Src.getScalarVal();
2020 // Cast the source to the storage type and shift it into place.
2021 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(),
2022 /*IsSigned=*/false);
2023 llvm::Value *MaskedVal = SrcVal;
2025 // See if there are other bits in the bitfield's storage we'll need to load
2026 // and mask together with source before storing.
2027 if (Info.StorageSize != Info.Size) {
2028 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
2030 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load");
2032 // Mask the source value as needed.
2033 if (!hasBooleanRepresentation(Dst.getType()))
2034 SrcVal = Builder.CreateAnd(SrcVal,
2035 llvm::APInt::getLowBitsSet(Info.StorageSize,
2040 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
2042 // Mask out the original value.
2043 Val = Builder.CreateAnd(Val,
2044 ~llvm::APInt::getBitsSet(Info.StorageSize,
2046 Info.Offset + Info.Size),
2049 // Or together the unchanged values and the source value.
2050 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
2052 assert(Info.Offset == 0);
2055 // Write the new value back out.
2056 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified());
2058 // Return the new value of the bit-field, if requested.
2060 llvm::Value *ResultVal = MaskedVal;
2062 // Sign extend the value if needed.
2063 if (Info.IsSigned) {
2064 assert(Info.Size <= Info.StorageSize);
2065 unsigned HighBits = Info.StorageSize - Info.Size;
2067 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
2068 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
2072 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
2074 *Result = EmitFromMemory(ResultVal, Dst.getType());
2078 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
2080 // This access turns into a read/modify/write of the vector. Load the input
2082 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddress(),
2083 Dst.isVolatileQualified());
2084 const llvm::Constant *Elts = Dst.getExtVectorElts();
2086 llvm::Value *SrcVal = Src.getScalarVal();
2088 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
2089 unsigned NumSrcElts = VTy->getNumElements();
2090 unsigned NumDstElts = Vec->getType()->getVectorNumElements();
2091 if (NumDstElts == NumSrcElts) {
2092 // Use shuffle vector is the src and destination are the same number of
2093 // elements and restore the vector mask since it is on the side it will be
2095 SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
2096 for (unsigned i = 0; i != NumSrcElts; ++i)
2097 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i);
2099 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
2100 Vec = Builder.CreateShuffleVector(SrcVal,
2101 llvm::UndefValue::get(Vec->getType()),
2103 } else if (NumDstElts > NumSrcElts) {
2104 // Extended the source vector to the same length and then shuffle it
2105 // into the destination.
2106 // FIXME: since we're shuffling with undef, can we just use the indices
2107 // into that? This could be simpler.
2108 SmallVector<llvm::Constant*, 4> ExtMask;
2109 for (unsigned i = 0; i != NumSrcElts; ++i)
2110 ExtMask.push_back(Builder.getInt32(i));
2111 ExtMask.resize(NumDstElts, llvm::UndefValue::get(Int32Ty));
2112 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
2113 llvm::Value *ExtSrcVal =
2114 Builder.CreateShuffleVector(SrcVal,
2115 llvm::UndefValue::get(SrcVal->getType()),
2118 SmallVector<llvm::Constant*, 4> Mask;
2119 for (unsigned i = 0; i != NumDstElts; ++i)
2120 Mask.push_back(Builder.getInt32(i));
2122 // When the vector size is odd and .odd or .hi is used, the last element
2123 // of the Elts constant array will be one past the size of the vector.
2124 // Ignore the last element here, if it is greater than the mask size.
2125 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
2128 // modify when what gets shuffled in
2129 for (unsigned i = 0; i != NumSrcElts; ++i)
2130 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i+NumDstElts);
2131 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
2132 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV);
2134 // We should never shorten the vector
2135 llvm_unreachable("unexpected shorten vector length");
2138 // If the Src is a scalar (not a vector) it must be updating one element.
2139 unsigned InIdx = getAccessedFieldNo(0, Elts);
2140 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
2141 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
2144 Builder.CreateStore(Vec, Dst.getExtVectorAddress(),
2145 Dst.isVolatileQualified());
2148 /// Store of global named registers are always calls to intrinsics.
2149 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
2150 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
2151 "Bad type for register variable");
2152 llvm::MDNode *RegName = cast<llvm::MDNode>(
2153 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata());
2154 assert(RegName && "Register LValue is not metadata");
2156 // We accept integer and pointer types only
2157 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
2158 llvm::Type *Ty = OrigTy;
2159 if (OrigTy->isPointerTy())
2160 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
2161 llvm::Type *Types[] = { Ty };
2163 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
2164 llvm::Value *Value = Src.getScalarVal();
2165 if (OrigTy->isPointerTy())
2166 Value = Builder.CreatePtrToInt(Value, Ty);
2168 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value});
2171 // setObjCGCLValueClass - sets class of the lvalue for the purpose of
2172 // generating write-barries API. It is currently a global, ivar,
2174 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
2176 bool IsMemberAccess=false) {
2177 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
2180 if (isa<ObjCIvarRefExpr>(E)) {
2181 QualType ExpTy = E->getType();
2182 if (IsMemberAccess && ExpTy->isPointerType()) {
2183 // If ivar is a structure pointer, assigning to field of
2184 // this struct follows gcc's behavior and makes it a non-ivar
2185 // writer-barrier conservatively.
2186 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
2187 if (ExpTy->isRecordType()) {
2188 LV.setObjCIvar(false);
2192 LV.setObjCIvar(true);
2193 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
2194 LV.setBaseIvarExp(Exp->getBase());
2195 LV.setObjCArray(E->getType()->isArrayType());
2199 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
2200 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
2201 if (VD->hasGlobalStorage()) {
2202 LV.setGlobalObjCRef(true);
2203 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
2206 LV.setObjCArray(E->getType()->isArrayType());
2210 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
2211 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2215 if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
2216 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2217 if (LV.isObjCIvar()) {
2218 // If cast is to a structure pointer, follow gcc's behavior and make it
2219 // a non-ivar write-barrier.
2220 QualType ExpTy = E->getType();
2221 if (ExpTy->isPointerType())
2222 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
2223 if (ExpTy->isRecordType())
2224 LV.setObjCIvar(false);
2229 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
2230 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
2234 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
2235 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2239 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
2240 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2244 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
2245 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2249 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
2250 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
2251 if (LV.isObjCIvar() && !LV.isObjCArray())
2252 // Using array syntax to assigning to what an ivar points to is not
2253 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
2254 LV.setObjCIvar(false);
2255 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
2256 // Using array syntax to assigning to what global points to is not
2257 // same as assigning to the global itself. {id *G;} G[i] = 0;
2258 LV.setGlobalObjCRef(false);
2262 if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
2263 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
2264 // We don't know if member is an 'ivar', but this flag is looked at
2265 // only in the context of LV.isObjCIvar().
2266 LV.setObjCArray(E->getType()->isArrayType());
2271 static llvm::Value *
2272 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
2273 llvm::Value *V, llvm::Type *IRType,
2274 StringRef Name = StringRef()) {
2275 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
2276 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
2279 static LValue EmitThreadPrivateVarDeclLValue(
2280 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr,
2281 llvm::Type *RealVarTy, SourceLocation Loc) {
2282 Addr = CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc);
2283 Addr = CGF.Builder.CreateElementBitCast(Addr, RealVarTy);
2284 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2287 static Address emitDeclTargetLinkVarDeclLValue(CodeGenFunction &CGF,
2288 const VarDecl *VD, QualType T) {
2289 llvm::Optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
2290 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD);
2291 if (!Res || *Res == OMPDeclareTargetDeclAttr::MT_To)
2292 return Address::invalid();
2293 assert(*Res == OMPDeclareTargetDeclAttr::MT_Link && "Expected link clause");
2294 QualType PtrTy = CGF.getContext().getPointerType(VD->getType());
2295 Address Addr = CGF.CGM.getOpenMPRuntime().getAddrOfDeclareTargetLink(VD);
2296 return CGF.EmitLoadOfPointer(Addr, PtrTy->castAs<PointerType>());
2300 CodeGenFunction::EmitLoadOfReference(LValue RefLVal,
2301 LValueBaseInfo *PointeeBaseInfo,
2302 TBAAAccessInfo *PointeeTBAAInfo) {
2303 llvm::LoadInst *Load = Builder.CreateLoad(RefLVal.getAddress(),
2304 RefLVal.isVolatile());
2305 CGM.DecorateInstructionWithTBAA(Load, RefLVal.getTBAAInfo());
2307 CharUnits Align = getNaturalTypeAlignment(RefLVal.getType()->getPointeeType(),
2308 PointeeBaseInfo, PointeeTBAAInfo,
2309 /* forPointeeType= */ true);
2310 return Address(Load, Align);
2313 LValue CodeGenFunction::EmitLoadOfReferenceLValue(LValue RefLVal) {
2314 LValueBaseInfo PointeeBaseInfo;
2315 TBAAAccessInfo PointeeTBAAInfo;
2316 Address PointeeAddr = EmitLoadOfReference(RefLVal, &PointeeBaseInfo,
2318 return MakeAddrLValue(PointeeAddr, RefLVal.getType()->getPointeeType(),
2319 PointeeBaseInfo, PointeeTBAAInfo);
2322 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr,
2323 const PointerType *PtrTy,
2324 LValueBaseInfo *BaseInfo,
2325 TBAAAccessInfo *TBAAInfo) {
2326 llvm::Value *Addr = Builder.CreateLoad(Ptr);
2327 return Address(Addr, getNaturalTypeAlignment(PtrTy->getPointeeType(),
2329 /*forPointeeType=*/true));
2332 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr,
2333 const PointerType *PtrTy) {
2334 LValueBaseInfo BaseInfo;
2335 TBAAAccessInfo TBAAInfo;
2336 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo, &TBAAInfo);
2337 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo, TBAAInfo);
2340 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
2341 const Expr *E, const VarDecl *VD) {
2342 QualType T = E->getType();
2344 // If it's thread_local, emit a call to its wrapper function instead.
2345 if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
2346 CGF.CGM.getCXXABI().usesThreadWrapperFunction())
2347 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
2348 // Check if the variable is marked as declare target with link clause in
2350 if (CGF.getLangOpts().OpenMPIsDevice) {
2351 Address Addr = emitDeclTargetLinkVarDeclLValue(CGF, VD, T);
2353 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2356 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
2357 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
2358 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
2359 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
2360 Address Addr(V, Alignment);
2361 // Emit reference to the private copy of the variable if it is an OpenMP
2362 // threadprivate variable.
2363 if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd &&
2364 VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2365 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
2368 LValue LV = VD->getType()->isReferenceType() ?
2369 CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(),
2370 AlignmentSource::Decl) :
2371 CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2372 setObjCGCLValueClass(CGF.getContext(), E, LV);
2376 static llvm::Constant *EmitFunctionDeclPointer(CodeGenModule &CGM,
2377 const FunctionDecl *FD) {
2378 if (FD->hasAttr<WeakRefAttr>()) {
2379 ConstantAddress aliasee = CGM.GetWeakRefReference(FD);
2380 return aliasee.getPointer();
2383 llvm::Constant *V = CGM.GetAddrOfFunction(FD);
2384 if (!FD->hasPrototype()) {
2385 if (const FunctionProtoType *Proto =
2386 FD->getType()->getAs<FunctionProtoType>()) {
2387 // Ugly case: for a K&R-style definition, the type of the definition
2388 // isn't the same as the type of a use. Correct for this with a
2390 QualType NoProtoType =
2391 CGM.getContext().getFunctionNoProtoType(Proto->getReturnType());
2392 NoProtoType = CGM.getContext().getPointerType(NoProtoType);
2393 V = llvm::ConstantExpr::getBitCast(V,
2394 CGM.getTypes().ConvertType(NoProtoType));
2400 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
2401 const Expr *E, const FunctionDecl *FD) {
2402 llvm::Value *V = EmitFunctionDeclPointer(CGF.CGM, FD);
2403 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
2404 return CGF.MakeAddrLValue(V, E->getType(), Alignment,
2405 AlignmentSource::Decl);
2408 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
2409 llvm::Value *ThisValue) {
2410 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
2411 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
2412 return CGF.EmitLValueForField(LV, FD);
2415 /// Named Registers are named metadata pointing to the register name
2416 /// which will be read from/written to as an argument to the intrinsic
2417 /// @llvm.read/write_register.
2418 /// So far, only the name is being passed down, but other options such as
2419 /// register type, allocation type or even optimization options could be
2420 /// passed down via the metadata node.
2421 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) {
2422 SmallString<64> Name("llvm.named.register.");
2423 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
2424 assert(Asm->getLabel().size() < 64-Name.size() &&
2425 "Register name too big");
2426 Name.append(Asm->getLabel());
2427 llvm::NamedMDNode *M =
2428 CGM.getModule().getOrInsertNamedMetadata(Name);
2429 if (M->getNumOperands() == 0) {
2430 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
2432 llvm::Metadata *Ops[] = {Str};
2433 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
2436 CharUnits Alignment = CGM.getContext().getDeclAlign(VD);
2439 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0));
2440 return LValue::MakeGlobalReg(Address(Ptr, Alignment), VD->getType());
2443 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
2444 const NamedDecl *ND = E->getDecl();
2445 QualType T = E->getType();
2447 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2448 // Global Named registers access via intrinsics only
2449 if (VD->getStorageClass() == SC_Register &&
2450 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
2451 return EmitGlobalNamedRegister(VD, CGM);
2453 // A DeclRefExpr for a reference initialized by a constant expression can
2454 // appear without being odr-used. Directly emit the constant initializer.
2455 const Expr *Init = VD->getAnyInitializer(VD);
2456 const auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl);
2457 if (Init && !isa<ParmVarDecl>(VD) && VD->getType()->isReferenceType() &&
2458 VD->isUsableInConstantExpressions(getContext()) &&
2459 VD->checkInitIsICE() &&
2460 // Do not emit if it is private OpenMP variable.
2461 !(E->refersToEnclosingVariableOrCapture() &&
2462 ((CapturedStmtInfo &&
2463 (LocalDeclMap.count(VD->getCanonicalDecl()) ||
2464 CapturedStmtInfo->lookup(VD->getCanonicalDecl()))) ||
2465 LambdaCaptureFields.lookup(VD->getCanonicalDecl()) ||
2466 (BD && BD->capturesVariable(VD))))) {
2467 llvm::Constant *Val =
2468 ConstantEmitter(*this).emitAbstract(E->getLocation(),
2469 *VD->evaluateValue(),
2471 assert(Val && "failed to emit reference constant expression");
2472 // FIXME: Eventually we will want to emit vector element references.
2474 // Should we be using the alignment of the constant pointer we emitted?
2475 CharUnits Alignment = getNaturalTypeAlignment(E->getType(),
2476 /* BaseInfo= */ nullptr,
2477 /* TBAAInfo= */ nullptr,
2478 /* forPointeeType= */ true);
2479 return MakeAddrLValue(Address(Val, Alignment), T, AlignmentSource::Decl);
2482 // Check for captured variables.
2483 if (E->refersToEnclosingVariableOrCapture()) {
2484 VD = VD->getCanonicalDecl();
2485 if (auto *FD = LambdaCaptureFields.lookup(VD))
2486 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
2487 else if (CapturedStmtInfo) {
2488 auto I = LocalDeclMap.find(VD);
2489 if (I != LocalDeclMap.end()) {
2490 if (VD->getType()->isReferenceType())
2491 return EmitLoadOfReferenceLValue(I->second, VD->getType(),
2492 AlignmentSource::Decl);
2493 return MakeAddrLValue(I->second, T);
2496 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD),
2497 CapturedStmtInfo->getContextValue());
2498 return MakeAddrLValue(
2499 Address(CapLVal.getPointer(), getContext().getDeclAlign(VD)),
2500 CapLVal.getType(), LValueBaseInfo(AlignmentSource::Decl),
2501 CapLVal.getTBAAInfo());
2504 assert(isa<BlockDecl>(CurCodeDecl));
2505 Address addr = GetAddrOfBlockDecl(VD);
2506 return MakeAddrLValue(addr, T, AlignmentSource::Decl);
2510 // FIXME: We should be able to assert this for FunctionDecls as well!
2511 // FIXME: We should be able to assert this for all DeclRefExprs, not just
2512 // those with a valid source location.
2513 assert((ND->isUsed(false) || !isa<VarDecl>(ND) ||
2514 !E->getLocation().isValid()) &&
2515 "Should not use decl without marking it used!");
2517 if (ND->hasAttr<WeakRefAttr>()) {
2518 const auto *VD = cast<ValueDecl>(ND);
2519 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD);
2520 return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl);
2523 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2524 // Check if this is a global variable.
2525 if (VD->hasLinkage() || VD->isStaticDataMember())
2526 return EmitGlobalVarDeclLValue(*this, E, VD);
2528 Address addr = Address::invalid();
2530 // The variable should generally be present in the local decl map.
2531 auto iter = LocalDeclMap.find(VD);
2532 if (iter != LocalDeclMap.end()) {
2533 addr = iter->second;
2535 // Otherwise, it might be static local we haven't emitted yet for
2536 // some reason; most likely, because it's in an outer function.
2537 } else if (VD->isStaticLocal()) {
2538 addr = Address(CGM.getOrCreateStaticVarDecl(
2539 *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)),
2540 getContext().getDeclAlign(VD));
2542 // No other cases for now.
2544 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?");
2548 // Check for OpenMP threadprivate variables.
2549 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd &&
2550 VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2551 return EmitThreadPrivateVarDeclLValue(
2552 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
2556 // Drill into block byref variables.
2557 bool isBlockByref = VD->isEscapingByref();
2559 addr = emitBlockByrefAddress(addr, VD);
2562 // Drill into reference types.
2563 LValue LV = VD->getType()->isReferenceType() ?
2564 EmitLoadOfReferenceLValue(addr, VD->getType(), AlignmentSource::Decl) :
2565 MakeAddrLValue(addr, T, AlignmentSource::Decl);
2567 bool isLocalStorage = VD->hasLocalStorage();
2569 bool NonGCable = isLocalStorage &&
2570 !VD->getType()->isReferenceType() &&
2573 LV.getQuals().removeObjCGCAttr();
2577 bool isImpreciseLifetime =
2578 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
2579 if (isImpreciseLifetime)
2580 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
2581 setObjCGCLValueClass(getContext(), E, LV);
2585 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
2586 return EmitFunctionDeclLValue(*this, E, FD);
2588 // FIXME: While we're emitting a binding from an enclosing scope, all other
2589 // DeclRefExprs we see should be implicitly treated as if they also refer to
2590 // an enclosing scope.
2591 if (const auto *BD = dyn_cast<BindingDecl>(ND))
2592 return EmitLValue(BD->getBinding());
2594 llvm_unreachable("Unhandled DeclRefExpr");
2597 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
2598 // __extension__ doesn't affect lvalue-ness.
2599 if (E->getOpcode() == UO_Extension)
2600 return EmitLValue(E->getSubExpr());
2602 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
2603 switch (E->getOpcode()) {
2604 default: llvm_unreachable("Unknown unary operator lvalue!");
2606 QualType T = E->getSubExpr()->getType()->getPointeeType();
2607 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
2609 LValueBaseInfo BaseInfo;
2610 TBAAAccessInfo TBAAInfo;
2611 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo,
2613 LValue LV = MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo);
2614 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
2616 // We should not generate __weak write barrier on indirect reference
2617 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
2618 // But, we continue to generate __strong write barrier on indirect write
2619 // into a pointer to object.
2620 if (getLangOpts().ObjC &&
2621 getLangOpts().getGC() != LangOptions::NonGC &&
2623 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2628 LValue LV = EmitLValue(E->getSubExpr());
2629 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
2631 // __real is valid on scalars. This is a faster way of testing that.
2632 // __imag can only produce an rvalue on scalars.
2633 if (E->getOpcode() == UO_Real &&
2634 !LV.getAddress().getElementType()->isStructTy()) {
2635 assert(E->getSubExpr()->getType()->isArithmeticType());
2639 QualType T = ExprTy->castAs<ComplexType>()->getElementType();
2642 (E->getOpcode() == UO_Real
2643 ? emitAddrOfRealComponent(LV.getAddress(), LV.getType())
2644 : emitAddrOfImagComponent(LV.getAddress(), LV.getType()));
2645 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo(),
2646 CGM.getTBAAInfoForSubobject(LV, T));
2647 ElemLV.getQuals().addQualifiers(LV.getQuals());
2652 LValue LV = EmitLValue(E->getSubExpr());
2653 bool isInc = E->getOpcode() == UO_PreInc;
2655 if (E->getType()->isAnyComplexType())
2656 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
2658 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
2664 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
2665 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
2666 E->getType(), AlignmentSource::Decl);
2669 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
2670 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
2671 E->getType(), AlignmentSource::Decl);
2674 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
2675 auto SL = E->getFunctionName();
2676 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr");
2677 StringRef FnName = CurFn->getName();
2678 if (FnName.startswith("\01"))
2679 FnName = FnName.substr(1);
2680 StringRef NameItems[] = {
2681 PredefinedExpr::getIdentKindName(E->getIdentKind()), FnName};
2682 std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
2683 if (auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl)) {
2684 std::string Name = SL->getString();
2685 if (!Name.empty()) {
2686 unsigned Discriminator =
2687 CGM.getCXXABI().getMangleContext().getBlockId(BD, true);
2689 Name += "_" + Twine(Discriminator + 1).str();
2690 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str());
2691 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2693 auto C = CGM.GetAddrOfConstantCString(FnName, GVName.c_str());
2694 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2697 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
2698 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2701 /// Emit a type description suitable for use by a runtime sanitizer library. The
2702 /// format of a type descriptor is
2705 /// { i16 TypeKind, i16 TypeInfo }
2708 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2709 /// integer, 1 for a floating point value, and -1 for anything else.
2710 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2711 // Only emit each type's descriptor once.
2712 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
2715 uint16_t TypeKind = -1;
2716 uint16_t TypeInfo = 0;
2718 if (T->isIntegerType()) {
2720 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2721 (T->isSignedIntegerType() ? 1 : 0);
2722 } else if (T->isFloatingType()) {
2724 TypeInfo = getContext().getTypeSize(T);
2727 // Format the type name as if for a diagnostic, including quotes and
2728 // optionally an 'aka'.
2729 SmallString<32> Buffer;
2730 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2731 (intptr_t)T.getAsOpaquePtr(),
2732 StringRef(), StringRef(), None, Buffer,
2735 llvm::Constant *Components[] = {
2736 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2737 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2739 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2741 auto *GV = new llvm::GlobalVariable(
2742 CGM.getModule(), Descriptor->getType(),
2743 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
2744 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2745 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV);
2747 // Remember the descriptor for this type.
2748 CGM.setTypeDescriptorInMap(T, GV);
2753 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2754 llvm::Type *TargetTy = IntPtrTy;
2756 if (V->getType() == TargetTy)
2759 // Floating-point types which fit into intptr_t are bitcast to integers
2760 // and then passed directly (after zero-extension, if necessary).
2761 if (V->getType()->isFloatingPointTy()) {
2762 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2763 if (Bits <= TargetTy->getIntegerBitWidth())
2764 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2768 // Integers which fit in intptr_t are zero-extended and passed directly.
2769 if (V->getType()->isIntegerTy() &&
2770 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2771 return Builder.CreateZExt(V, TargetTy);
2773 // Pointers are passed directly, everything else is passed by address.
2774 if (!V->getType()->isPointerTy()) {
2775 Address Ptr = CreateDefaultAlignTempAlloca(V->getType());
2776 Builder.CreateStore(V, Ptr);
2777 V = Ptr.getPointer();
2779 return Builder.CreatePtrToInt(V, TargetTy);
2782 /// Emit a representation of a SourceLocation for passing to a handler
2783 /// in a sanitizer runtime library. The format for this data is:
2785 /// struct SourceLocation {
2786 /// const char *Filename;
2787 /// int32_t Line, Column;
2790 /// For an invalid SourceLocation, the Filename pointer is null.
2791 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
2792 llvm::Constant *Filename;
2795 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
2796 if (PLoc.isValid()) {
2797 StringRef FilenameString = PLoc.getFilename();
2799 int PathComponentsToStrip =
2800 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip;
2801 if (PathComponentsToStrip < 0) {
2802 assert(PathComponentsToStrip != INT_MIN);
2803 int PathComponentsToKeep = -PathComponentsToStrip;
2804 auto I = llvm::sys::path::rbegin(FilenameString);
2805 auto E = llvm::sys::path::rend(FilenameString);
2806 while (I != E && --PathComponentsToKeep)
2809 FilenameString = FilenameString.substr(I - E);
2810 } else if (PathComponentsToStrip > 0) {
2811 auto I = llvm::sys::path::begin(FilenameString);
2812 auto E = llvm::sys::path::end(FilenameString);
2813 while (I != E && PathComponentsToStrip--)
2818 FilenameString.substr(I - llvm::sys::path::begin(FilenameString));
2820 FilenameString = llvm::sys::path::filename(FilenameString);
2823 auto FilenameGV = CGM.GetAddrOfConstantCString(FilenameString, ".src");
2824 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
2825 cast<llvm::GlobalVariable>(FilenameGV.getPointer()));
2826 Filename = FilenameGV.getPointer();
2827 Line = PLoc.getLine();
2828 Column = PLoc.getColumn();
2830 Filename = llvm::Constant::getNullValue(Int8PtrTy);
2834 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
2835 Builder.getInt32(Column)};
2837 return llvm::ConstantStruct::getAnon(Data);
2841 /// Specify under what conditions this check can be recovered
2842 enum class CheckRecoverableKind {
2843 /// Always terminate program execution if this check fails.
2845 /// Check supports recovering, runtime has both fatal (noreturn) and
2846 /// non-fatal handlers for this check.
2848 /// Runtime conditionally aborts, always need to support recovery.
2853 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) {
2854 assert(llvm::countPopulation(Kind) == 1);
2856 case SanitizerKind::Vptr:
2857 return CheckRecoverableKind::AlwaysRecoverable;
2858 case SanitizerKind::Return:
2859 case SanitizerKind::Unreachable:
2860 return CheckRecoverableKind::Unrecoverable;
2862 return CheckRecoverableKind::Recoverable;
2867 struct SanitizerHandlerInfo {
2868 char const *const Name;
2873 const SanitizerHandlerInfo SanitizerHandlers[] = {
2874 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version},
2875 LIST_SANITIZER_CHECKS
2876 #undef SANITIZER_CHECK
2879 static void emitCheckHandlerCall(CodeGenFunction &CGF,
2880 llvm::FunctionType *FnType,
2881 ArrayRef<llvm::Value *> FnArgs,
2882 SanitizerHandler CheckHandler,
2883 CheckRecoverableKind RecoverKind, bool IsFatal,
2884 llvm::BasicBlock *ContBB) {
2885 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable);
2886 Optional<ApplyDebugLocation> DL;
2887 if (!CGF.Builder.getCurrentDebugLocation()) {
2888 // Ensure that the call has at least an artificial debug location.
2889 DL.emplace(CGF, SourceLocation());
2891 bool NeedsAbortSuffix =
2892 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable;
2893 bool MinimalRuntime = CGF.CGM.getCodeGenOpts().SanitizeMinimalRuntime;
2894 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler];
2895 const StringRef CheckName = CheckInfo.Name;
2896 std::string FnName = "__ubsan_handle_" + CheckName.str();
2897 if (CheckInfo.Version && !MinimalRuntime)
2898 FnName += "_v" + llvm::utostr(CheckInfo.Version);
2900 FnName += "_minimal";
2901 if (NeedsAbortSuffix)
2904 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable;
2906 llvm::AttrBuilder B;
2908 B.addAttribute(llvm::Attribute::NoReturn)
2909 .addAttribute(llvm::Attribute::NoUnwind);
2911 B.addAttribute(llvm::Attribute::UWTable);
2913 llvm::Value *Fn = CGF.CGM.CreateRuntimeFunction(
2915 llvm::AttributeList::get(CGF.getLLVMContext(),
2916 llvm::AttributeList::FunctionIndex, B),
2918 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs);
2920 HandlerCall->setDoesNotReturn();
2921 CGF.Builder.CreateUnreachable();
2923 CGF.Builder.CreateBr(ContBB);
2927 void CodeGenFunction::EmitCheck(
2928 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
2929 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs,
2930 ArrayRef<llvm::Value *> DynamicArgs) {
2931 assert(IsSanitizerScope);
2932 assert(Checked.size() > 0);
2933 assert(CheckHandler >= 0 &&
2934 size_t(CheckHandler) < llvm::array_lengthof(SanitizerHandlers));
2935 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name;
2937 llvm::Value *FatalCond = nullptr;
2938 llvm::Value *RecoverableCond = nullptr;
2939 llvm::Value *TrapCond = nullptr;
2940 for (int i = 0, n = Checked.size(); i < n; ++i) {
2941 llvm::Value *Check = Checked[i].first;
2942 // -fsanitize-trap= overrides -fsanitize-recover=.
2943 llvm::Value *&Cond =
2944 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second)
2946 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second)
2949 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check;
2953 EmitTrapCheck(TrapCond);
2954 if (!FatalCond && !RecoverableCond)
2957 llvm::Value *JointCond;
2958 if (FatalCond && RecoverableCond)
2959 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond);
2961 JointCond = FatalCond ? FatalCond : RecoverableCond;
2964 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second);
2965 assert(SanOpts.has(Checked[0].second));
2967 for (int i = 1, n = Checked.size(); i < n; ++i) {
2968 assert(RecoverKind == getRecoverableKind(Checked[i].second) &&
2969 "All recoverable kinds in a single check must be same!");
2970 assert(SanOpts.has(Checked[i].second));
2974 llvm::BasicBlock *Cont = createBasicBlock("cont");
2975 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName);
2976 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers);
2977 // Give hint that we very much don't expect to execute the handler
2978 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
2979 llvm::MDBuilder MDHelper(getLLVMContext());
2980 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2981 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
2982 EmitBlock(Handlers);
2984 // Handler functions take an i8* pointing to the (handler-specific) static
2985 // information block, followed by a sequence of intptr_t arguments
2986 // representing operand values.
2987 SmallVector<llvm::Value *, 4> Args;
2988 SmallVector<llvm::Type *, 4> ArgTypes;
2989 if (!CGM.getCodeGenOpts().SanitizeMinimalRuntime) {
2990 Args.reserve(DynamicArgs.size() + 1);
2991 ArgTypes.reserve(DynamicArgs.size() + 1);
2993 // Emit handler arguments and create handler function type.
2994 if (!StaticArgs.empty()) {
2995 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2997 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2998 llvm::GlobalVariable::PrivateLinkage, Info);
2999 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3000 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3001 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
3002 ArgTypes.push_back(Int8PtrTy);
3005 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
3006 Args.push_back(EmitCheckValue(DynamicArgs[i]));
3007 ArgTypes.push_back(IntPtrTy);
3011 llvm::FunctionType *FnType =
3012 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
3014 if (!FatalCond || !RecoverableCond) {
3015 // Simple case: we need to generate a single handler call, either
3016 // fatal, or non-fatal.
3017 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind,
3018 (FatalCond != nullptr), Cont);
3020 // Emit two handler calls: first one for set of unrecoverable checks,
3021 // another one for recoverable.
3022 llvm::BasicBlock *NonFatalHandlerBB =
3023 createBasicBlock("non_fatal." + CheckName);
3024 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName);
3025 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB);
3026 EmitBlock(FatalHandlerBB);
3027 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true,
3029 EmitBlock(NonFatalHandlerBB);
3030 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false,
3037 void CodeGenFunction::EmitCfiSlowPathCheck(
3038 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId,
3039 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) {
3040 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont");
3042 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath");
3043 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB);
3045 llvm::MDBuilder MDHelper(getLLVMContext());
3046 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
3047 BI->setMetadata(llvm::LLVMContext::MD_prof, Node);
3051 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind);
3053 llvm::CallInst *CheckCall;
3054 llvm::Constant *SlowPathFn;
3056 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3058 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
3059 llvm::GlobalVariable::PrivateLinkage, Info);
3060 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3061 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3063 SlowPathFn = CGM.getModule().getOrInsertFunction(
3064 "__cfi_slowpath_diag",
3065 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy},
3067 CheckCall = Builder.CreateCall(
3068 SlowPathFn, {TypeId, Ptr, Builder.CreateBitCast(InfoPtr, Int8PtrTy)});
3070 SlowPathFn = CGM.getModule().getOrInsertFunction(
3072 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false));
3073 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr});
3076 CGM.setDSOLocal(cast<llvm::GlobalValue>(SlowPathFn->stripPointerCasts()));
3077 CheckCall->setDoesNotThrow();
3082 // Emit a stub for __cfi_check function so that the linker knows about this
3083 // symbol in LTO mode.
3084 void CodeGenFunction::EmitCfiCheckStub() {
3085 llvm::Module *M = &CGM.getModule();
3086 auto &Ctx = M->getContext();
3087 llvm::Function *F = llvm::Function::Create(
3088 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false),
3089 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M);
3091 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F);
3092 // FIXME: consider emitting an intrinsic call like
3093 // call void @llvm.cfi_check(i64 %0, i8* %1, i8* %2)
3094 // which can be lowered in CrossDSOCFI pass to the actual contents of
3095 // __cfi_check. This would allow inlining of __cfi_check calls.
3096 llvm::CallInst::Create(
3097 llvm::Intrinsic::getDeclaration(M, llvm::Intrinsic::trap), "", BB);
3098 llvm::ReturnInst::Create(Ctx, nullptr, BB);
3101 // This function is basically a switch over the CFI failure kind, which is
3102 // extracted from CFICheckFailData (1st function argument). Each case is either
3103 // llvm.trap or a call to one of the two runtime handlers, based on
3104 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid
3105 // failure kind) traps, but this should really never happen. CFICheckFailData
3106 // can be nullptr if the calling module has -fsanitize-trap behavior for this
3107 // check kind; in this case __cfi_check_fail traps as well.
3108 void CodeGenFunction::EmitCfiCheckFail() {
3109 SanitizerScope SanScope(this);
3110 FunctionArgList Args;
3111 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy,
3112 ImplicitParamDecl::Other);
3113 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy,
3114 ImplicitParamDecl::Other);
3115 Args.push_back(&ArgData);
3116 Args.push_back(&ArgAddr);
3118 const CGFunctionInfo &FI =
3119 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args);
3121 llvm::Function *F = llvm::Function::Create(
3122 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false),
3123 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule());
3124 F->setVisibility(llvm::GlobalValue::HiddenVisibility);
3126 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args,
3129 // This function should not be affected by blacklist. This function does
3130 // not have a source location, but "src:*" would still apply. Revert any
3131 // changes to SanOpts made in StartFunction.
3132 SanOpts = CGM.getLangOpts().Sanitize;
3135 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false,
3136 CGM.getContext().VoidPtrTy, ArgData.getLocation());
3138 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false,
3139 CGM.getContext().VoidPtrTy, ArgAddr.getLocation());
3141 // Data == nullptr means the calling module has trap behaviour for this check.
3142 llvm::Value *DataIsNotNullPtr =
3143 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy));
3144 EmitTrapCheck(DataIsNotNullPtr);
3146 llvm::StructType *SourceLocationTy =
3147 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty);
3148 llvm::StructType *CfiCheckFailDataTy =
3149 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy);
3151 llvm::Value *V = Builder.CreateConstGEP2_32(
3153 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0,
3155 Address CheckKindAddr(V, getIntAlign());
3156 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr);
3158 llvm::Value *AllVtables = llvm::MetadataAsValue::get(
3159 CGM.getLLVMContext(),
3160 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
3161 llvm::Value *ValidVtable = Builder.CreateZExt(
3162 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test),
3163 {Addr, AllVtables}),
3166 const std::pair<int, SanitizerMask> CheckKinds[] = {
3167 {CFITCK_VCall, SanitizerKind::CFIVCall},
3168 {CFITCK_NVCall, SanitizerKind::CFINVCall},
3169 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast},
3170 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast},
3171 {CFITCK_ICall, SanitizerKind::CFIICall}};
3173 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks;
3174 for (auto CheckKindMaskPair : CheckKinds) {
3175 int Kind = CheckKindMaskPair.first;
3176 SanitizerMask Mask = CheckKindMaskPair.second;
3178 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind));
3179 if (CGM.getLangOpts().Sanitize.has(Mask))
3180 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {},
3181 {Data, Addr, ValidVtable});
3183 EmitTrapCheck(Cond);
3187 // The only reference to this function will be created during LTO link.
3188 // Make sure it survives until then.
3189 CGM.addUsedGlobal(F);
3192 void CodeGenFunction::EmitUnreachable(SourceLocation Loc) {
3193 if (SanOpts.has(SanitizerKind::Unreachable)) {
3194 SanitizerScope SanScope(this);
3195 EmitCheck(std::make_pair(static_cast<llvm::Value *>(Builder.getFalse()),
3196 SanitizerKind::Unreachable),
3197 SanitizerHandler::BuiltinUnreachable,
3198 EmitCheckSourceLocation(Loc), None);
3200 Builder.CreateUnreachable();
3203 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
3204 llvm::BasicBlock *Cont = createBasicBlock("cont");
3206 // If we're optimizing, collapse all calls to trap down to just one per
3207 // function to save on code size.
3208 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
3209 TrapBB = createBasicBlock("trap");
3210 Builder.CreateCondBr(Checked, Cont, TrapBB);
3212 llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
3213 TrapCall->setDoesNotReturn();
3214 TrapCall->setDoesNotThrow();
3215 Builder.CreateUnreachable();
3217 Builder.CreateCondBr(Checked, Cont, TrapBB);
3223 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) {
3224 llvm::CallInst *TrapCall = Builder.CreateCall(CGM.getIntrinsic(IntrID));
3226 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
3227 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",
3228 CGM.getCodeGenOpts().TrapFuncName);
3229 TrapCall->addAttribute(llvm::AttributeList::FunctionIndex, A);
3235 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E,
3236 LValueBaseInfo *BaseInfo,
3237 TBAAAccessInfo *TBAAInfo) {
3238 assert(E->getType()->isArrayType() &&
3239 "Array to pointer decay must have array source type!");
3241 // Expressions of array type can't be bitfields or vector elements.
3242 LValue LV = EmitLValue(E);
3243 Address Addr = LV.getAddress();
3245 // If the array type was an incomplete type, we need to make sure
3246 // the decay ends up being the right type.
3247 llvm::Type *NewTy = ConvertType(E->getType());
3248 Addr = Builder.CreateElementBitCast(Addr, NewTy);
3250 // Note that VLA pointers are always decayed, so we don't need to do
3252 if (!E->getType()->isVariableArrayType()) {
3253 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3254 "Expected pointer to array");
3255 Addr = Builder.CreateStructGEP(Addr, 0, CharUnits::Zero(), "arraydecay");
3258 // The result of this decay conversion points to an array element within the
3259 // base lvalue. However, since TBAA currently does not support representing
3260 // accesses to elements of member arrays, we conservatively represent accesses
3261 // to the pointee object as if it had no any base lvalue specified.
3262 // TODO: Support TBAA for member arrays.
3263 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType();
3264 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
3265 if (TBAAInfo) *TBAAInfo = CGM.getTBAAAccessInfo(EltType);
3267 return Builder.CreateElementBitCast(Addr, ConvertTypeForMem(EltType));
3270 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
3271 /// array to pointer, return the array subexpression.
3272 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
3273 // If this isn't just an array->pointer decay, bail out.
3274 const auto *CE = dyn_cast<CastExpr>(E);
3275 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
3278 // If this is a decay from variable width array, bail out.
3279 const Expr *SubExpr = CE->getSubExpr();
3280 if (SubExpr->getType()->isVariableArrayType())
3286 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
3288 ArrayRef<llvm::Value*> indices,
3292 const llvm::Twine &name = "arrayidx") {
3294 return CGF.EmitCheckedInBoundsGEP(ptr, indices, signedIndices,
3295 CodeGenFunction::NotSubtraction, loc,
3298 return CGF.Builder.CreateGEP(ptr, indices, name);
3302 static CharUnits getArrayElementAlign(CharUnits arrayAlign,
3304 CharUnits eltSize) {
3305 // If we have a constant index, we can use the exact offset of the
3306 // element we're accessing.
3307 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) {
3308 CharUnits offset = constantIdx->getZExtValue() * eltSize;
3309 return arrayAlign.alignmentAtOffset(offset);
3311 // Otherwise, use the worst-case alignment for any element.
3313 return arrayAlign.alignmentOfArrayElement(eltSize);
3317 static QualType getFixedSizeElementType(const ASTContext &ctx,
3318 const VariableArrayType *vla) {
3321 eltType = vla->getElementType();
3322 } while ((vla = ctx.getAsVariableArrayType(eltType)));
3326 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
3327 ArrayRef<llvm::Value *> indices,
3328 QualType eltType, bool inbounds,
3329 bool signedIndices, SourceLocation loc,
3330 const llvm::Twine &name = "arrayidx") {
3331 // All the indices except that last must be zero.
3333 for (auto idx : indices.drop_back())
3334 assert(isa<llvm::ConstantInt>(idx) &&
3335 cast<llvm::ConstantInt>(idx)->isZero());
3338 // Determine the element size of the statically-sized base. This is
3339 // the thing that the indices are expressed in terms of.
3340 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) {
3341 eltType = getFixedSizeElementType(CGF.getContext(), vla);
3344 // We can use that to compute the best alignment of the element.
3345 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
3346 CharUnits eltAlign =
3347 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
3349 llvm::Value *eltPtr = emitArraySubscriptGEP(
3350 CGF, addr.getPointer(), indices, inbounds, signedIndices, loc, name);
3351 return Address(eltPtr, eltAlign);
3354 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3356 // The index must always be an integer, which is not an aggregate. Emit it
3357 // in lexical order (this complexity is, sadly, required by C++17).
3358 llvm::Value *IdxPre =
3359 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr;
3360 bool SignedIndices = false;
3361 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * {
3363 if (E->getLHS() != E->getIdx()) {
3364 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS");
3365 Idx = EmitScalarExpr(E->getIdx());
3368 QualType IdxTy = E->getIdx()->getType();
3369 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
3370 SignedIndices |= IdxSigned;
3372 if (SanOpts.has(SanitizerKind::ArrayBounds))
3373 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
3375 // Extend or truncate the index type to 32 or 64-bits.
3376 if (Promote && Idx->getType() != IntPtrTy)
3377 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
3383 // If the base is a vector type, then we are forming a vector element lvalue
3384 // with this subscript.
3385 if (E->getBase()->getType()->isVectorType() &&
3386 !isa<ExtVectorElementExpr>(E->getBase())) {
3387 // Emit the vector as an lvalue to get its address.
3388 LValue LHS = EmitLValue(E->getBase());
3389 auto *Idx = EmitIdxAfterBase(/*Promote*/false);
3390 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
3391 return LValue::MakeVectorElt(LHS.getAddress(), Idx, E->getBase()->getType(),
3392 LHS.getBaseInfo(), TBAAAccessInfo());
3395 // All the other cases basically behave like simple offsetting.
3397 // Handle the extvector case we ignored above.
3398 if (isa<ExtVectorElementExpr>(E->getBase())) {
3399 LValue LV = EmitLValue(E->getBase());
3400 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3401 Address Addr = EmitExtVectorElementLValue(LV);
3403 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
3404 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true,
3405 SignedIndices, E->getExprLoc());
3406 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo(),
3407 CGM.getTBAAInfoForSubobject(LV, EltType));
3410 LValueBaseInfo EltBaseInfo;
3411 TBAAAccessInfo EltTBAAInfo;
3412 Address Addr = Address::invalid();
3413 if (const VariableArrayType *vla =
3414 getContext().getAsVariableArrayType(E->getType())) {
3415 // The base must be a pointer, which is not an aggregate. Emit
3416 // it. It needs to be emitted first in case it's what captures
3418 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3419 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3421 // The element count here is the total number of non-VLA elements.
3422 llvm::Value *numElements = getVLASize(vla).NumElts;
3424 // Effectively, the multiply by the VLA size is part of the GEP.
3425 // GEP indexes are signed, and scaling an index isn't permitted to
3426 // signed-overflow, so we use the same semantics for our explicit
3427 // multiply. We suppress this if overflow is not undefined behavior.
3428 if (getLangOpts().isSignedOverflowDefined()) {
3429 Idx = Builder.CreateMul(Idx, numElements);
3431 Idx = Builder.CreateNSWMul(Idx, numElements);
3434 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
3435 !getLangOpts().isSignedOverflowDefined(),
3436 SignedIndices, E->getExprLoc());
3438 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
3439 // Indexing over an interface, as in "NSString *P; P[4];"
3441 // Emit the base pointer.
3442 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3443 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3445 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT);
3446 llvm::Value *InterfaceSizeVal =
3447 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity());
3449 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal);
3451 // We don't necessarily build correct LLVM struct types for ObjC
3452 // interfaces, so we can't rely on GEP to do this scaling
3453 // correctly, so we need to cast to i8*. FIXME: is this actually
3454 // true? A lot of other things in the fragile ABI would break...
3455 llvm::Type *OrigBaseTy = Addr.getType();
3456 Addr = Builder.CreateElementBitCast(Addr, Int8Ty);
3459 CharUnits EltAlign =
3460 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
3461 llvm::Value *EltPtr =
3462 emitArraySubscriptGEP(*this, Addr.getPointer(), ScaledIdx, false,
3463 SignedIndices, E->getExprLoc());
3464 Addr = Address(EltPtr, EltAlign);
3467 Addr = Builder.CreateBitCast(Addr, OrigBaseTy);
3468 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3469 // If this is A[i] where A is an array, the frontend will have decayed the
3470 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3471 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3472 // "gep x, i" here. Emit one "gep A, 0, i".
3473 assert(Array->getType()->isArrayType() &&
3474 "Array to pointer decay must have array source type!");
3476 // For simple multidimensional array indexing, set the 'accessed' flag for
3477 // better bounds-checking of the base expression.
3478 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3479 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3481 ArrayLV = EmitLValue(Array);
3482 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3484 // Propagate the alignment from the array itself to the result.
3485 Addr = emitArraySubscriptGEP(
3486 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3487 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices,
3489 EltBaseInfo = ArrayLV.getBaseInfo();
3490 EltTBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, E->getType());
3492 // The base must be a pointer; emit it with an estimate of its alignment.
3493 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3494 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3495 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
3496 !getLangOpts().isSignedOverflowDefined(),
3497 SignedIndices, E->getExprLoc());
3500 LValue LV = MakeAddrLValue(Addr, E->getType(), EltBaseInfo, EltTBAAInfo);
3502 if (getLangOpts().ObjC &&
3503 getLangOpts().getGC() != LangOptions::NonGC) {
3504 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
3505 setObjCGCLValueClass(getContext(), E, LV);
3510 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base,
3511 LValueBaseInfo &BaseInfo,
3512 TBAAAccessInfo &TBAAInfo,
3513 QualType BaseTy, QualType ElTy,
3514 bool IsLowerBound) {
3516 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) {
3517 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound);
3518 if (BaseTy->isArrayType()) {
3519 Address Addr = BaseLVal.getAddress();
3520 BaseInfo = BaseLVal.getBaseInfo();
3522 // If the array type was an incomplete type, we need to make sure
3523 // the decay ends up being the right type.
3524 llvm::Type *NewTy = CGF.ConvertType(BaseTy);
3525 Addr = CGF.Builder.CreateElementBitCast(Addr, NewTy);
3527 // Note that VLA pointers are always decayed, so we don't need to do
3529 if (!BaseTy->isVariableArrayType()) {
3530 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3531 "Expected pointer to array");
3532 Addr = CGF.Builder.CreateStructGEP(Addr, 0, CharUnits::Zero(),
3536 return CGF.Builder.CreateElementBitCast(Addr,
3537 CGF.ConvertTypeForMem(ElTy));
3539 LValueBaseInfo TypeBaseInfo;
3540 TBAAAccessInfo TypeTBAAInfo;
3541 CharUnits Align = CGF.getNaturalTypeAlignment(ElTy, &TypeBaseInfo,
3543 BaseInfo.mergeForCast(TypeBaseInfo);
3544 TBAAInfo = CGF.CGM.mergeTBAAInfoForCast(TBAAInfo, TypeTBAAInfo);
3545 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress()), Align);
3547 return CGF.EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo);
3550 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3551 bool IsLowerBound) {
3552 QualType BaseTy = OMPArraySectionExpr::getBaseOriginalType(E->getBase());
3553 QualType ResultExprTy;
3554 if (auto *AT = getContext().getAsArrayType(BaseTy))
3555 ResultExprTy = AT->getElementType();
3557 ResultExprTy = BaseTy->getPointeeType();
3558 llvm::Value *Idx = nullptr;
3559 if (IsLowerBound || E->getColonLoc().isInvalid()) {
3560 // Requesting lower bound or upper bound, but without provided length and
3561 // without ':' symbol for the default length -> length = 1.
3562 // Idx = LowerBound ?: 0;
3563 if (auto *LowerBound = E->getLowerBound()) {
3564 Idx = Builder.CreateIntCast(
3565 EmitScalarExpr(LowerBound), IntPtrTy,
3566 LowerBound->getType()->hasSignedIntegerRepresentation());
3568 Idx = llvm::ConstantInt::getNullValue(IntPtrTy);
3570 // Try to emit length or lower bound as constant. If this is possible, 1
3571 // is subtracted from constant length or lower bound. Otherwise, emit LLVM
3572 // IR (LB + Len) - 1.
3573 auto &C = CGM.getContext();
3574 auto *Length = E->getLength();
3575 llvm::APSInt ConstLength;
3577 // Idx = LowerBound + Length - 1;
3578 if (Length->isIntegerConstantExpr(ConstLength, C)) {
3579 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3582 auto *LowerBound = E->getLowerBound();
3583 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false);
3584 if (LowerBound && LowerBound->isIntegerConstantExpr(ConstLowerBound, C)) {
3585 ConstLowerBound = ConstLowerBound.zextOrTrunc(PointerWidthInBits);
3586 LowerBound = nullptr;
3590 else if (!LowerBound)
3593 if (Length || LowerBound) {
3594 auto *LowerBoundVal =
3596 ? Builder.CreateIntCast(
3597 EmitScalarExpr(LowerBound), IntPtrTy,
3598 LowerBound->getType()->hasSignedIntegerRepresentation())
3599 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound);
3602 ? Builder.CreateIntCast(
3603 EmitScalarExpr(Length), IntPtrTy,
3604 Length->getType()->hasSignedIntegerRepresentation())
3605 : llvm::ConstantInt::get(IntPtrTy, ConstLength);
3606 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len",
3608 !getLangOpts().isSignedOverflowDefined());
3609 if (Length && LowerBound) {
3610 Idx = Builder.CreateSub(
3611 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1",
3612 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3615 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound);
3617 // Idx = ArraySize - 1;
3618 QualType ArrayTy = BaseTy->isPointerType()
3619 ? E->getBase()->IgnoreParenImpCasts()->getType()
3621 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) {
3622 Length = VAT->getSizeExpr();
3623 if (Length->isIntegerConstantExpr(ConstLength, C))
3626 auto *CAT = C.getAsConstantArrayType(ArrayTy);
3627 ConstLength = CAT->getSize();
3630 auto *LengthVal = Builder.CreateIntCast(
3631 EmitScalarExpr(Length), IntPtrTy,
3632 Length->getType()->hasSignedIntegerRepresentation());
3633 Idx = Builder.CreateSub(
3634 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1",
3635 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3637 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3639 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength);
3645 Address EltPtr = Address::invalid();
3646 LValueBaseInfo BaseInfo;
3647 TBAAAccessInfo TBAAInfo;
3648 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) {
3649 // The base must be a pointer, which is not an aggregate. Emit
3650 // it. It needs to be emitted first in case it's what captures
3653 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo,
3654 BaseTy, VLA->getElementType(), IsLowerBound);
3655 // The element count here is the total number of non-VLA elements.
3656 llvm::Value *NumElements = getVLASize(VLA).NumElts;
3658 // Effectively, the multiply by the VLA size is part of the GEP.
3659 // GEP indexes are signed, and scaling an index isn't permitted to
3660 // signed-overflow, so we use the same semantics for our explicit
3661 // multiply. We suppress this if overflow is not undefined behavior.
3662 if (getLangOpts().isSignedOverflowDefined())
3663 Idx = Builder.CreateMul(Idx, NumElements);
3665 Idx = Builder.CreateNSWMul(Idx, NumElements);
3666 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
3667 !getLangOpts().isSignedOverflowDefined(),
3668 /*SignedIndices=*/false, E->getExprLoc());
3669 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3670 // If this is A[i] where A is an array, the frontend will have decayed the
3671 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3672 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3673 // "gep x, i" here. Emit one "gep A, 0, i".
3674 assert(Array->getType()->isArrayType() &&
3675 "Array to pointer decay must have array source type!");
3677 // For simple multidimensional array indexing, set the 'accessed' flag for
3678 // better bounds-checking of the base expression.
3679 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3680 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3682 ArrayLV = EmitLValue(Array);
3684 // Propagate the alignment from the array itself to the result.
3685 EltPtr = emitArraySubscriptGEP(
3686 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3687 ResultExprTy, !getLangOpts().isSignedOverflowDefined(),
3688 /*SignedIndices=*/false, E->getExprLoc());
3689 BaseInfo = ArrayLV.getBaseInfo();
3690 TBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, ResultExprTy);
3692 Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo,
3693 TBAAInfo, BaseTy, ResultExprTy,
3695 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
3696 !getLangOpts().isSignedOverflowDefined(),
3697 /*SignedIndices=*/false, E->getExprLoc());
3700 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo, TBAAInfo);
3703 LValue CodeGenFunction::
3704 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
3705 // Emit the base vector as an l-value.
3708 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
3710 // If it is a pointer to a vector, emit the address and form an lvalue with
3712 LValueBaseInfo BaseInfo;
3713 TBAAAccessInfo TBAAInfo;
3714 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo, &TBAAInfo);
3715 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
3716 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo, TBAAInfo);
3717 Base.getQuals().removeObjCGCAttr();
3718 } else if (E->getBase()->isGLValue()) {
3719 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
3720 // emit the base as an lvalue.
3721 assert(E->getBase()->getType()->isVectorType());
3722 Base = EmitLValue(E->getBase());
3724 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
3725 assert(E->getBase()->getType()->isVectorType() &&
3726 "Result must be a vector");
3727 llvm::Value *Vec = EmitScalarExpr(E->getBase());
3729 // Store the vector to memory (because LValue wants an address).
3730 Address VecMem = CreateMemTemp(E->getBase()->getType());
3731 Builder.CreateStore(Vec, VecMem);
3732 Base = MakeAddrLValue(VecMem, E->getBase()->getType(),
3733 AlignmentSource::Decl);
3737 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
3739 // Encode the element access list into a vector of unsigned indices.
3740 SmallVector<uint32_t, 4> Indices;
3741 E->getEncodedElementAccess(Indices);
3743 if (Base.isSimple()) {
3744 llvm::Constant *CV =
3745 llvm::ConstantDataVector::get(getLLVMContext(), Indices);
3746 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
3747 Base.getBaseInfo(), TBAAAccessInfo());
3749 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
3751 llvm::Constant *BaseElts = Base.getExtVectorElts();
3752 SmallVector<llvm::Constant *, 4> CElts;
3754 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
3755 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
3756 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
3757 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type,
3758 Base.getBaseInfo(), TBAAAccessInfo());
3761 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
3762 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, E)) {
3763 EmitIgnoredExpr(E->getBase());
3764 return EmitDeclRefLValue(DRE);
3767 Expr *BaseExpr = E->getBase();
3768 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
3771 LValueBaseInfo BaseInfo;
3772 TBAAAccessInfo TBAAInfo;
3773 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo, &TBAAInfo);
3774 QualType PtrTy = BaseExpr->getType()->getPointeeType();
3775 SanitizerSet SkippedChecks;
3776 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr);
3778 SkippedChecks.set(SanitizerKind::Alignment, true);
3779 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr))
3780 SkippedChecks.set(SanitizerKind::Null, true);
3781 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy,
3782 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
3783 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo, TBAAInfo);
3785 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
3787 NamedDecl *ND = E->getMemberDecl();
3788 if (auto *Field = dyn_cast<FieldDecl>(ND)) {
3789 LValue LV = EmitLValueForField(BaseLV, Field);
3790 setObjCGCLValueClass(getContext(), E, LV);
3794 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
3795 return EmitFunctionDeclLValue(*this, E, FD);
3797 llvm_unreachable("Unhandled member declaration!");
3800 /// Given that we are currently emitting a lambda, emit an l-value for
3801 /// one of its members.
3802 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
3803 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
3804 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
3805 QualType LambdaTagType =
3806 getContext().getTagDeclType(Field->getParent());
3807 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
3808 return EmitLValueForField(LambdaLV, Field);
3811 /// Drill down to the storage of a field without walking into
3812 /// reference types.
3814 /// The resulting address doesn't necessarily have the right type.
3815 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
3816 const FieldDecl *field) {
3817 const RecordDecl *rec = field->getParent();
3820 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
3823 // Adjust the alignment down to the given offset.
3824 // As a special case, if the LLVM field index is 0, we know that this
3826 assert((idx != 0 || CGF.getContext().getASTRecordLayout(rec)
3827 .getFieldOffset(field->getFieldIndex()) == 0) &&
3828 "LLVM field at index zero had non-zero offset?");
3830 auto &recLayout = CGF.getContext().getASTRecordLayout(rec);
3831 auto offsetInBits = recLayout.getFieldOffset(field->getFieldIndex());
3832 offset = CGF.getContext().toCharUnitsFromBits(offsetInBits);
3835 return CGF.Builder.CreateStructGEP(base, idx, offset, field->getName());
3838 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) {
3839 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl();
3843 if (RD->isDynamicClass())
3846 for (const auto &Base : RD->bases())
3847 if (hasAnyVptr(Base.getType(), Context))
3850 for (const FieldDecl *Field : RD->fields())
3851 if (hasAnyVptr(Field->getType(), Context))
3857 LValue CodeGenFunction::EmitLValueForField(LValue base,
3858 const FieldDecl *field) {
3859 LValueBaseInfo BaseInfo = base.getBaseInfo();
3861 if (field->isBitField()) {
3862 const CGRecordLayout &RL =
3863 CGM.getTypes().getCGRecordLayout(field->getParent());
3864 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
3865 Address Addr = base.getAddress();
3866 unsigned Idx = RL.getLLVMFieldNo(field);
3868 // For structs, we GEP to the field that the record layout suggests.
3869 Addr = Builder.CreateStructGEP(Addr, Idx, Info.StorageOffset,
3871 // Get the access type.
3872 llvm::Type *FieldIntTy =
3873 llvm::Type::getIntNTy(getLLVMContext(), Info.StorageSize);
3874 if (Addr.getElementType() != FieldIntTy)
3875 Addr = Builder.CreateElementBitCast(Addr, FieldIntTy);
3877 QualType fieldType =
3878 field->getType().withCVRQualifiers(base.getVRQualifiers());
3879 // TODO: Support TBAA for bit fields.
3880 LValueBaseInfo FieldBaseInfo(BaseInfo.getAlignmentSource());
3881 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo,
3885 // Fields of may-alias structures are may-alias themselves.
3886 // FIXME: this should get propagated down through anonymous structs
3888 QualType FieldType = field->getType();
3889 const RecordDecl *rec = field->getParent();
3890 AlignmentSource BaseAlignSource = BaseInfo.getAlignmentSource();
3891 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(BaseAlignSource));
3892 TBAAAccessInfo FieldTBAAInfo;
3893 if (base.getTBAAInfo().isMayAlias() ||
3894 rec->hasAttr<MayAliasAttr>() || FieldType->isVectorType()) {
3895 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
3896 } else if (rec->isUnion()) {
3897 // TODO: Support TBAA for unions.
3898 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
3900 // If no base type been assigned for the base access, then try to generate
3901 // one for this base lvalue.
3902 FieldTBAAInfo = base.getTBAAInfo();
3903 if (!FieldTBAAInfo.BaseType) {
3904 FieldTBAAInfo.BaseType = CGM.getTBAABaseTypeInfo(base.getType());
3905 assert(!FieldTBAAInfo.Offset &&
3906 "Nonzero offset for an access with no base type!");
3909 // Adjust offset to be relative to the base type.
3910 const ASTRecordLayout &Layout =
3911 getContext().getASTRecordLayout(field->getParent());
3912 unsigned CharWidth = getContext().getCharWidth();
3913 if (FieldTBAAInfo.BaseType)
3914 FieldTBAAInfo.Offset +=
3915 Layout.getFieldOffset(field->getFieldIndex()) / CharWidth;
3917 // Update the final access type and size.
3918 FieldTBAAInfo.AccessType = CGM.getTBAATypeInfo(FieldType);
3919 FieldTBAAInfo.Size =
3920 getContext().getTypeSizeInChars(FieldType).getQuantity();
3923 Address addr = base.getAddress();
3924 if (auto *ClassDef = dyn_cast<CXXRecordDecl>(rec)) {
3925 if (CGM.getCodeGenOpts().StrictVTablePointers &&
3926 ClassDef->isDynamicClass()) {
3927 // Getting to any field of dynamic object requires stripping dynamic
3928 // information provided by invariant.group. This is because accessing
3929 // fields may leak the real address of dynamic object, which could result
3930 // in miscompilation when leaked pointer would be compared.
3931 auto *stripped = Builder.CreateStripInvariantGroup(addr.getPointer());
3932 addr = Address(stripped, addr.getAlignment());
3936 unsigned RecordCVR = base.getVRQualifiers();
3937 if (rec->isUnion()) {
3938 // For unions, there is no pointer adjustment.
3939 assert(!FieldType->isReferenceType() && "union has reference member");
3940 if (CGM.getCodeGenOpts().StrictVTablePointers &&
3941 hasAnyVptr(FieldType, getContext()))
3942 // Because unions can easily skip invariant.barriers, we need to add
3943 // a barrier every time CXXRecord field with vptr is referenced.
3944 addr = Address(Builder.CreateLaunderInvariantGroup(addr.getPointer()),
3945 addr.getAlignment());
3947 // For structs, we GEP to the field that the record layout suggests.
3948 addr = emitAddrOfFieldStorage(*this, addr, field);
3950 // If this is a reference field, load the reference right now.
3951 if (FieldType->isReferenceType()) {
3952 LValue RefLVal = MakeAddrLValue(addr, FieldType, FieldBaseInfo,
3954 if (RecordCVR & Qualifiers::Volatile)
3955 RefLVal.getQuals().addVolatile();
3956 addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo);
3958 // Qualifiers on the struct don't apply to the referencee.
3960 FieldType = FieldType->getPointeeType();
3964 // Make sure that the address is pointing to the right type. This is critical
3965 // for both unions and structs. A union needs a bitcast, a struct element
3966 // will need a bitcast if the LLVM type laid out doesn't match the desired
3968 addr = Builder.CreateElementBitCast(
3969 addr, CGM.getTypes().ConvertTypeForMem(FieldType), field->getName());
3971 if (field->hasAttr<AnnotateAttr>())
3972 addr = EmitFieldAnnotations(field, addr);
3974 LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
3975 LV.getQuals().addCVRQualifiers(RecordCVR);
3977 // __weak attribute on a field is ignored.
3978 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
3979 LV.getQuals().removeObjCGCAttr();
3985 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
3986 const FieldDecl *Field) {
3987 QualType FieldType = Field->getType();
3989 if (!FieldType->isReferenceType())
3990 return EmitLValueForField(Base, Field);
3992 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(), Field);
3994 // Make sure that the address is pointing to the right type.
3995 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
3996 V = Builder.CreateElementBitCast(V, llvmType, Field->getName());
3998 // TODO: Generate TBAA information that describes this access as a structure
3999 // member access and not just an access to an object of the field's type. This
4000 // should be similar to what we do in EmitLValueForField().
4001 LValueBaseInfo BaseInfo = Base.getBaseInfo();
4002 AlignmentSource FieldAlignSource = BaseInfo.getAlignmentSource();
4003 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(FieldAlignSource));
4004 return MakeAddrLValue(V, FieldType, FieldBaseInfo,
4005 CGM.getTBAAInfoForSubobject(Base, FieldType));
4008 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
4009 if (E->isFileScope()) {
4010 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
4011 return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl);
4013 if (E->getType()->isVariablyModifiedType())
4014 // make sure to emit the VLA size.
4015 EmitVariablyModifiedType(E->getType());
4017 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
4018 const Expr *InitExpr = E->getInitializer();
4019 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl);
4021 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
4027 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
4028 if (!E->isGLValue())
4029 // Initializing an aggregate temporary in C++11: T{...}.
4030 return EmitAggExprToLValue(E);
4032 // An lvalue initializer list must be initializing a reference.
4033 assert(E->isTransparent() && "non-transparent glvalue init list");
4034 return EmitLValue(E->getInit(0));
4037 /// Emit the operand of a glvalue conditional operator. This is either a glvalue
4038 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no
4039 /// LValue is returned and the current block has been terminated.
4040 static Optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
4041 const Expr *Operand) {
4042 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
4043 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
4047 return CGF.EmitLValue(Operand);
4050 LValue CodeGenFunction::
4051 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
4052 if (!expr->isGLValue()) {
4053 // ?: here should be an aggregate.
4054 assert(hasAggregateEvaluationKind(expr->getType()) &&
4055 "Unexpected conditional operator!");
4056 return EmitAggExprToLValue(expr);
4059 OpaqueValueMapping binding(*this, expr);
4061 const Expr *condExpr = expr->getCond();
4063 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
4064 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
4065 if (!CondExprBool) std::swap(live, dead);
4067 if (!ContainsLabel(dead)) {
4068 // If the true case is live, we need to track its region.
4070 incrementProfileCounter(expr);
4071 return EmitLValue(live);
4075 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
4076 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
4077 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
4079 ConditionalEvaluation eval(*this);
4080 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock, getProfileCount(expr));
4082 // Any temporaries created here are conditional.
4083 EmitBlock(lhsBlock);
4084 incrementProfileCounter(expr);
4086 Optional<LValue> lhs =
4087 EmitLValueOrThrowExpression(*this, expr->getTrueExpr());
4090 if (lhs && !lhs->isSimple())
4091 return EmitUnsupportedLValue(expr, "conditional operator");
4093 lhsBlock = Builder.GetInsertBlock();
4095 Builder.CreateBr(contBlock);
4097 // Any temporaries created here are conditional.
4098 EmitBlock(rhsBlock);
4100 Optional<LValue> rhs =
4101 EmitLValueOrThrowExpression(*this, expr->getFalseExpr());
4103 if (rhs && !rhs->isSimple())
4104 return EmitUnsupportedLValue(expr, "conditional operator");
4105 rhsBlock = Builder.GetInsertBlock();
4107 EmitBlock(contBlock);
4110 llvm::PHINode *phi = Builder.CreatePHI(lhs->getPointer()->getType(),
4112 phi->addIncoming(lhs->getPointer(), lhsBlock);
4113 phi->addIncoming(rhs->getPointer(), rhsBlock);
4114 Address result(phi, std::min(lhs->getAlignment(), rhs->getAlignment()));
4115 AlignmentSource alignSource =
4116 std::max(lhs->getBaseInfo().getAlignmentSource(),
4117 rhs->getBaseInfo().getAlignmentSource());
4118 TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForConditionalOperator(
4119 lhs->getTBAAInfo(), rhs->getTBAAInfo());
4120 return MakeAddrLValue(result, expr->getType(), LValueBaseInfo(alignSource),
4123 assert((lhs || rhs) &&
4124 "both operands of glvalue conditional are throw-expressions?");
4125 return lhs ? *lhs : *rhs;
4129 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
4130 /// type. If the cast is to a reference, we can have the usual lvalue result,
4131 /// otherwise if a cast is needed by the code generator in an lvalue context,
4132 /// then it must mean that we need the address of an aggregate in order to
4133 /// access one of its members. This can happen for all the reasons that casts
4134 /// are permitted with aggregate result, including noop aggregate casts, and
4135 /// cast from scalar to union.
4136 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
4137 switch (E->getCastKind()) {
4140 case CK_ArrayToPointerDecay:
4141 case CK_FunctionToPointerDecay:
4142 case CK_NullToMemberPointer:
4143 case CK_NullToPointer:
4144 case CK_IntegralToPointer:
4145 case CK_PointerToIntegral:
4146 case CK_PointerToBoolean:
4147 case CK_VectorSplat:
4148 case CK_IntegralCast:
4149 case CK_BooleanToSignedIntegral:
4150 case CK_IntegralToBoolean:
4151 case CK_IntegralToFloating:
4152 case CK_FloatingToIntegral:
4153 case CK_FloatingToBoolean:
4154 case CK_FloatingCast:
4155 case CK_FloatingRealToComplex:
4156 case CK_FloatingComplexToReal:
4157 case CK_FloatingComplexToBoolean:
4158 case CK_FloatingComplexCast:
4159 case CK_FloatingComplexToIntegralComplex:
4160 case CK_IntegralRealToComplex:
4161 case CK_IntegralComplexToReal:
4162 case CK_IntegralComplexToBoolean:
4163 case CK_IntegralComplexCast:
4164 case CK_IntegralComplexToFloatingComplex:
4165 case CK_DerivedToBaseMemberPointer:
4166 case CK_BaseToDerivedMemberPointer:
4167 case CK_MemberPointerToBoolean:
4168 case CK_ReinterpretMemberPointer:
4169 case CK_AnyPointerToBlockPointerCast:
4170 case CK_ARCProduceObject:
4171 case CK_ARCConsumeObject:
4172 case CK_ARCReclaimReturnedObject:
4173 case CK_ARCExtendBlockObject:
4174 case CK_CopyAndAutoreleaseBlockObject:
4175 case CK_IntToOCLSampler:
4176 case CK_FixedPointCast:
4177 case CK_FixedPointToBoolean:
4178 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
4181 llvm_unreachable("dependent cast kind in IR gen!");
4183 case CK_BuiltinFnToFnPtr:
4184 llvm_unreachable("builtin functions are handled elsewhere");
4186 // These are never l-values; just use the aggregate emission code.
4187 case CK_NonAtomicToAtomic:
4188 case CK_AtomicToNonAtomic:
4189 return EmitAggExprToLValue(E);
4192 LValue LV = EmitLValue(E->getSubExpr());
4193 Address V = LV.getAddress();
4194 const auto *DCE = cast<CXXDynamicCastExpr>(E);
4195 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType());
4198 case CK_ConstructorConversion:
4199 case CK_UserDefinedConversion:
4200 case CK_CPointerToObjCPointerCast:
4201 case CK_BlockPointerToObjCPointerCast:
4203 case CK_LValueToRValue:
4204 return EmitLValue(E->getSubExpr());
4206 case CK_UncheckedDerivedToBase:
4207 case CK_DerivedToBase: {
4208 const RecordType *DerivedClassTy =
4209 E->getSubExpr()->getType()->getAs<RecordType>();
4210 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
4212 LValue LV = EmitLValue(E->getSubExpr());
4213 Address This = LV.getAddress();
4215 // Perform the derived-to-base conversion
4216 Address Base = GetAddressOfBaseClass(
4217 This, DerivedClassDecl, E->path_begin(), E->path_end(),
4218 /*NullCheckValue=*/false, E->getExprLoc());
4220 // TODO: Support accesses to members of base classes in TBAA. For now, we
4221 // conservatively pretend that the complete object is of the base class
4223 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo(),
4224 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4227 return EmitAggExprToLValue(E);
4228 case CK_BaseToDerived: {
4229 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
4230 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
4232 LValue LV = EmitLValue(E->getSubExpr());
4234 // Perform the base-to-derived conversion
4236 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
4237 E->path_begin(), E->path_end(),
4238 /*NullCheckValue=*/false);
4240 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
4241 // performed and the object is not of the derived type.
4242 if (sanitizePerformTypeCheck())
4243 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
4244 Derived.getPointer(), E->getType());
4246 if (SanOpts.has(SanitizerKind::CFIDerivedCast))
4247 EmitVTablePtrCheckForCast(E->getType(), Derived.getPointer(),
4248 /*MayBeNull=*/false, CFITCK_DerivedCast,
4251 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo(),
4252 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4254 case CK_LValueBitCast: {
4255 // This must be a reinterpret_cast (or c-style equivalent).
4256 const auto *CE = cast<ExplicitCastExpr>(E);
4258 CGM.EmitExplicitCastExprType(CE, this);
4259 LValue LV = EmitLValue(E->getSubExpr());
4260 Address V = Builder.CreateBitCast(LV.getAddress(),
4261 ConvertType(CE->getTypeAsWritten()));
4263 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast))
4264 EmitVTablePtrCheckForCast(E->getType(), V.getPointer(),
4265 /*MayBeNull=*/false, CFITCK_UnrelatedCast,
4268 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
4269 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4271 case CK_AddressSpaceConversion: {
4272 LValue LV = EmitLValue(E->getSubExpr());
4273 QualType DestTy = getContext().getPointerType(E->getType());
4274 llvm::Value *V = getTargetHooks().performAddrSpaceCast(
4275 *this, LV.getPointer(), E->getSubExpr()->getType().getAddressSpace(),
4276 E->getType().getAddressSpace(), ConvertType(DestTy));
4277 return MakeAddrLValue(Address(V, LV.getAddress().getAlignment()),
4278 E->getType(), LV.getBaseInfo(), LV.getTBAAInfo());
4280 case CK_ObjCObjectLValueCast: {
4281 LValue LV = EmitLValue(E->getSubExpr());
4282 Address V = Builder.CreateElementBitCast(LV.getAddress(),
4283 ConvertType(E->getType()));
4284 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
4285 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4287 case CK_ZeroToOCLOpaqueType:
4288 llvm_unreachable("NULL to OpenCL opaque type lvalue cast is not valid");
4291 llvm_unreachable("Unhandled lvalue cast kind?");
4294 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
4295 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
4296 return getOrCreateOpaqueLValueMapping(e);
4300 CodeGenFunction::getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e) {
4301 assert(OpaqueValueMapping::shouldBindAsLValue(e));
4303 llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator
4304 it = OpaqueLValues.find(e);
4306 if (it != OpaqueLValues.end())
4309 assert(e->isUnique() && "LValue for a nonunique OVE hasn't been emitted");
4310 return EmitLValue(e->getSourceExpr());
4314 CodeGenFunction::getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e) {
4315 assert(!OpaqueValueMapping::shouldBindAsLValue(e));
4317 llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator
4318 it = OpaqueRValues.find(e);
4320 if (it != OpaqueRValues.end())
4323 assert(e->isUnique() && "RValue for a nonunique OVE hasn't been emitted");
4324 return EmitAnyExpr(e->getSourceExpr());
4327 RValue CodeGenFunction::EmitRValueForField(LValue LV,
4328 const FieldDecl *FD,
4329 SourceLocation Loc) {
4330 QualType FT = FD->getType();
4331 LValue FieldLV = EmitLValueForField(LV, FD);
4332 switch (getEvaluationKind(FT)) {
4334 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
4336 return FieldLV.asAggregateRValue();
4338 // This routine is used to load fields one-by-one to perform a copy, so
4339 // don't load reference fields.
4340 if (FD->getType()->isReferenceType())
4341 return RValue::get(FieldLV.getPointer());
4342 return EmitLoadOfLValue(FieldLV, Loc);
4344 llvm_unreachable("bad evaluation kind");
4347 //===--------------------------------------------------------------------===//
4348 // Expression Emission
4349 //===--------------------------------------------------------------------===//
4351 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
4352 ReturnValueSlot ReturnValue) {
4353 // Builtins never have block type.
4354 if (E->getCallee()->getType()->isBlockPointerType())
4355 return EmitBlockCallExpr(E, ReturnValue);
4357 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
4358 return EmitCXXMemberCallExpr(CE, ReturnValue);
4360 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
4361 return EmitCUDAKernelCallExpr(CE, ReturnValue);
4363 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
4364 if (const CXXMethodDecl *MD =
4365 dyn_cast_or_null<CXXMethodDecl>(CE->getCalleeDecl()))
4366 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
4368 CGCallee callee = EmitCallee(E->getCallee());
4370 if (callee.isBuiltin()) {
4371 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(),
4375 if (callee.isPseudoDestructor()) {
4376 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr());
4379 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue);
4382 /// Emit a CallExpr without considering whether it might be a subclass.
4383 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E,
4384 ReturnValueSlot ReturnValue) {
4385 CGCallee Callee = EmitCallee(E->getCallee());
4386 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue);
4389 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, const FunctionDecl *FD) {
4390 if (auto builtinID = FD->getBuiltinID()) {
4391 return CGCallee::forBuiltin(builtinID, FD);
4394 llvm::Constant *calleePtr = EmitFunctionDeclPointer(CGF.CGM, FD);
4395 return CGCallee::forDirect(calleePtr, GlobalDecl(FD));
4398 CGCallee CodeGenFunction::EmitCallee(const Expr *E) {
4399 E = E->IgnoreParens();
4401 // Look through function-to-pointer decay.
4402 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) {
4403 if (ICE->getCastKind() == CK_FunctionToPointerDecay ||
4404 ICE->getCastKind() == CK_BuiltinFnToFnPtr) {
4405 return EmitCallee(ICE->getSubExpr());
4408 // Resolve direct calls.
4409 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) {
4410 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
4411 return EmitDirectCallee(*this, FD);
4413 } else if (auto ME = dyn_cast<MemberExpr>(E)) {
4414 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) {
4415 EmitIgnoredExpr(ME->getBase());
4416 return EmitDirectCallee(*this, FD);
4419 // Look through template substitutions.
4420 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
4421 return EmitCallee(NTTP->getReplacement());
4423 // Treat pseudo-destructor calls differently.
4424 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) {
4425 return CGCallee::forPseudoDestructor(PDE);
4428 // Otherwise, we have an indirect reference.
4429 llvm::Value *calleePtr;
4430 QualType functionType;
4431 if (auto ptrType = E->getType()->getAs<PointerType>()) {
4432 calleePtr = EmitScalarExpr(E);
4433 functionType = ptrType->getPointeeType();
4435 functionType = E->getType();
4436 calleePtr = EmitLValue(E).getPointer();
4438 assert(functionType->isFunctionType());
4441 if (const auto *VD =
4442 dyn_cast_or_null<VarDecl>(E->getReferencedDeclOfCallee()))
4443 GD = GlobalDecl(VD);
4445 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(), GD);
4446 CGCallee callee(calleeInfo, calleePtr);
4450 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
4451 // Comma expressions just emit their LHS then their RHS as an l-value.
4452 if (E->getOpcode() == BO_Comma) {
4453 EmitIgnoredExpr(E->getLHS());
4454 EnsureInsertPoint();
4455 return EmitLValue(E->getRHS());
4458 if (E->getOpcode() == BO_PtrMemD ||
4459 E->getOpcode() == BO_PtrMemI)
4460 return EmitPointerToDataMemberBinaryExpr(E);
4462 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
4464 // Note that in all of these cases, __block variables need the RHS
4465 // evaluated first just in case the variable gets moved by the RHS.
4467 switch (getEvaluationKind(E->getType())) {
4469 switch (E->getLHS()->getType().getObjCLifetime()) {
4470 case Qualifiers::OCL_Strong:
4471 return EmitARCStoreStrong(E, /*ignored*/ false).first;
4473 case Qualifiers::OCL_Autoreleasing:
4474 return EmitARCStoreAutoreleasing(E).first;
4476 // No reason to do any of these differently.
4477 case Qualifiers::OCL_None:
4478 case Qualifiers::OCL_ExplicitNone:
4479 case Qualifiers::OCL_Weak:
4483 RValue RV = EmitAnyExpr(E->getRHS());
4484 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
4486 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc());
4487 EmitStoreThroughLValue(RV, LV);
4492 return EmitComplexAssignmentLValue(E);
4495 return EmitAggExprToLValue(E);
4497 llvm_unreachable("bad evaluation kind");
4500 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
4501 RValue RV = EmitCallExpr(E);
4504 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4505 AlignmentSource::Decl);
4507 assert(E->getCallReturnType(getContext())->isReferenceType() &&
4508 "Can't have a scalar return unless the return type is a "
4511 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4514 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
4515 // FIXME: This shouldn't require another copy.
4516 return EmitAggExprToLValue(E);
4519 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
4520 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
4521 && "binding l-value to type which needs a temporary");
4522 AggValueSlot Slot = CreateAggTemp(E->getType());
4523 EmitCXXConstructExpr(E, Slot);
4524 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4528 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
4529 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType());
4532 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
4533 return Builder.CreateElementBitCast(CGM.GetAddrOfUuidDescriptor(E),
4534 ConvertType(E->getType()));
4537 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
4538 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(),
4539 AlignmentSource::Decl);
4543 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
4544 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4545 Slot.setExternallyDestructed();
4546 EmitAggExpr(E->getSubExpr(), Slot);
4547 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress());
4548 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4552 CodeGenFunction::EmitLambdaLValue(const LambdaExpr *E) {
4553 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4554 EmitLambdaExpr(E, Slot);
4555 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4558 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
4559 RValue RV = EmitObjCMessageExpr(E);
4562 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4563 AlignmentSource::Decl);
4565 assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
4566 "Can't have a scalar return unless the return type is a "
4569 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4572 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
4574 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector());
4575 return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl);
4578 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
4579 const ObjCIvarDecl *Ivar) {
4580 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
4583 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
4584 llvm::Value *BaseValue,
4585 const ObjCIvarDecl *Ivar,
4586 unsigned CVRQualifiers) {
4587 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
4588 Ivar, CVRQualifiers);
4591 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
4592 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
4593 llvm::Value *BaseValue = nullptr;
4594 const Expr *BaseExpr = E->getBase();
4595 Qualifiers BaseQuals;
4598 BaseValue = EmitScalarExpr(BaseExpr);
4599 ObjectTy = BaseExpr->getType()->getPointeeType();
4600 BaseQuals = ObjectTy.getQualifiers();
4602 LValue BaseLV = EmitLValue(BaseExpr);
4603 BaseValue = BaseLV.getPointer();
4604 ObjectTy = BaseExpr->getType();
4605 BaseQuals = ObjectTy.getQualifiers();
4609 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
4610 BaseQuals.getCVRQualifiers());
4611 setObjCGCLValueClass(getContext(), E, LV);
4615 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
4616 // Can only get l-value for message expression returning aggregate type
4617 RValue RV = EmitAnyExprToTemp(E);
4618 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4619 AlignmentSource::Decl);
4622 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee,
4623 const CallExpr *E, ReturnValueSlot ReturnValue,
4624 llvm::Value *Chain) {
4625 // Get the actual function type. The callee type will always be a pointer to
4626 // function type or a block pointer type.
4627 assert(CalleeType->isFunctionPointerType() &&
4628 "Call must have function pointer type!");
4630 const Decl *TargetDecl =
4631 OrigCallee.getAbstractInfo().getCalleeDecl().getDecl();
4633 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl))
4634 // We can only guarantee that a function is called from the correct
4635 // context/function based on the appropriate target attributes,
4636 // so only check in the case where we have both always_inline and target
4637 // since otherwise we could be making a conditional call after a check for
4638 // the proper cpu features (and it won't cause code generation issues due to
4639 // function based code generation).
4640 if (TargetDecl->hasAttr<AlwaysInlineAttr>() &&
4641 TargetDecl->hasAttr<TargetAttr>())
4642 checkTargetFeatures(E, FD);
4644 CalleeType = getContext().getCanonicalType(CalleeType);
4646 auto PointeeType = cast<PointerType>(CalleeType)->getPointeeType();
4648 CGCallee Callee = OrigCallee;
4650 if (getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function) &&
4651 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4652 if (llvm::Constant *PrefixSig =
4653 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
4654 SanitizerScope SanScope(this);
4655 // Remove any (C++17) exception specifications, to allow calling e.g. a
4656 // noexcept function through a non-noexcept pointer.
4658 getContext().getFunctionTypeWithExceptionSpec(PointeeType, EST_None);
4659 llvm::Constant *FTRTTIConst =
4660 CGM.GetAddrOfRTTIDescriptor(ProtoTy, /*ForEH=*/true);
4661 llvm::Type *PrefixStructTyElems[] = {PrefixSig->getType(), Int32Ty};
4662 llvm::StructType *PrefixStructTy = llvm::StructType::get(
4663 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
4665 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4667 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
4668 CalleePtr, llvm::PointerType::getUnqual(PrefixStructTy));
4669 llvm::Value *CalleeSigPtr =
4670 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 0);
4671 llvm::Value *CalleeSig =
4672 Builder.CreateAlignedLoad(CalleeSigPtr, getIntAlign());
4673 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
4675 llvm::BasicBlock *Cont = createBasicBlock("cont");
4676 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
4677 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
4679 EmitBlock(TypeCheck);
4680 llvm::Value *CalleeRTTIPtr =
4681 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 1);
4682 llvm::Value *CalleeRTTIEncoded =
4683 Builder.CreateAlignedLoad(CalleeRTTIPtr, getPointerAlign());
4684 llvm::Value *CalleeRTTI =
4685 DecodeAddrUsedInPrologue(CalleePtr, CalleeRTTIEncoded);
4686 llvm::Value *CalleeRTTIMatch =
4687 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
4688 llvm::Constant *StaticData[] = {EmitCheckSourceLocation(E->getBeginLoc()),
4689 EmitCheckTypeDescriptor(CalleeType)};
4690 EmitCheck(std::make_pair(CalleeRTTIMatch, SanitizerKind::Function),
4691 SanitizerHandler::FunctionTypeMismatch, StaticData, CalleePtr);
4693 Builder.CreateBr(Cont);
4698 const auto *FnType = cast<FunctionType>(PointeeType);
4700 // If we are checking indirect calls and this call is indirect, check that the
4701 // function pointer is a member of the bit set for the function type.
4702 if (SanOpts.has(SanitizerKind::CFIICall) &&
4703 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4704 SanitizerScope SanScope(this);
4705 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
4708 if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers)
4709 MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0));
4711 MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
4713 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD);
4715 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4716 llvm::Value *CastedCallee = Builder.CreateBitCast(CalleePtr, Int8PtrTy);
4717 llvm::Value *TypeTest = Builder.CreateCall(
4718 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CastedCallee, TypeId});
4720 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD);
4721 llvm::Constant *StaticData[] = {
4722 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall),
4723 EmitCheckSourceLocation(E->getBeginLoc()),
4724 EmitCheckTypeDescriptor(QualType(FnType, 0)),
4726 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) {
4727 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId,
4728 CastedCallee, StaticData);
4730 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall),
4731 SanitizerHandler::CFICheckFail, StaticData,
4732 {CastedCallee, llvm::UndefValue::get(IntPtrTy)});
4738 Args.add(RValue::get(Builder.CreateBitCast(Chain, CGM.VoidPtrTy)),
4739 CGM.getContext().VoidPtrTy);
4741 // C++17 requires that we evaluate arguments to a call using assignment syntax
4742 // right-to-left, and that we evaluate arguments to certain other operators
4743 // left-to-right. Note that we allow this to override the order dictated by
4744 // the calling convention on the MS ABI, which means that parameter
4745 // destruction order is not necessarily reverse construction order.
4746 // FIXME: Revisit this based on C++ committee response to unimplementability.
4747 EvaluationOrder Order = EvaluationOrder::Default;
4748 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) {
4749 if (OCE->isAssignmentOp())
4750 Order = EvaluationOrder::ForceRightToLeft;
4752 switch (OCE->getOperator()) {
4754 case OO_GreaterGreater:
4759 Order = EvaluationOrder::ForceLeftToRight;
4767 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(),
4768 E->getDirectCallee(), /*ParamsToSkip*/ 0, Order);
4770 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall(
4771 Args, FnType, /*isChainCall=*/Chain);
4774 // If the expression that denotes the called function has a type
4775 // that does not include a prototype, [the default argument
4776 // promotions are performed]. If the number of arguments does not
4777 // equal the number of parameters, the behavior is undefined. If
4778 // the function is defined with a type that includes a prototype,
4779 // and either the prototype ends with an ellipsis (, ...) or the
4780 // types of the arguments after promotion are not compatible with
4781 // the types of the parameters, the behavior is undefined. If the
4782 // function is defined with a type that does not include a
4783 // prototype, and the types of the arguments after promotion are
4784 // not compatible with those of the parameters after promotion,
4785 // the behavior is undefined [except in some trivial cases].
4786 // That is, in the general case, we should assume that a call
4787 // through an unprototyped function type works like a *non-variadic*
4788 // call. The way we make this work is to cast to the exact type
4789 // of the promoted arguments.
4791 // Chain calls use this same code path to add the invisible chain parameter
4792 // to the function type.
4793 if (isa<FunctionNoProtoType>(FnType) || Chain) {
4794 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
4795 CalleeTy = CalleeTy->getPointerTo();
4797 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4798 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast");
4799 Callee.setFunctionPointer(CalleePtr);
4802 return EmitCall(FnInfo, Callee, ReturnValue, Args, nullptr, E->getExprLoc());
4805 LValue CodeGenFunction::
4806 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
4807 Address BaseAddr = Address::invalid();
4808 if (E->getOpcode() == BO_PtrMemI) {
4809 BaseAddr = EmitPointerWithAlignment(E->getLHS());
4811 BaseAddr = EmitLValue(E->getLHS()).getAddress();
4814 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
4816 const MemberPointerType *MPT
4817 = E->getRHS()->getType()->getAs<MemberPointerType>();
4819 LValueBaseInfo BaseInfo;
4820 TBAAAccessInfo TBAAInfo;
4821 Address MemberAddr =
4822 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo,
4825 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo, TBAAInfo);
4828 /// Given the address of a temporary variable, produce an r-value of
4830 RValue CodeGenFunction::convertTempToRValue(Address addr,
4832 SourceLocation loc) {
4833 LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl);
4834 switch (getEvaluationKind(type)) {
4836 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
4838 return lvalue.asAggregateRValue();
4840 return RValue::get(EmitLoadOfScalar(lvalue, loc));
4842 llvm_unreachable("bad evaluation kind");
4845 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
4846 assert(Val->getType()->isFPOrFPVectorTy());
4847 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
4850 llvm::MDBuilder MDHelper(getLLVMContext());
4851 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
4853 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
4857 struct LValueOrRValue {
4863 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
4864 const PseudoObjectExpr *E,
4866 AggValueSlot slot) {
4867 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
4869 // Find the result expression, if any.
4870 const Expr *resultExpr = E->getResultExpr();
4871 LValueOrRValue result;
4873 for (PseudoObjectExpr::const_semantics_iterator
4874 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
4875 const Expr *semantic = *i;
4877 // If this semantic expression is an opaque value, bind it
4878 // to the result of its source expression.
4879 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
4880 // Skip unique OVEs.
4881 if (ov->isUnique()) {
4882 assert(ov != resultExpr &&
4883 "A unique OVE cannot be used as the result expression");
4887 // If this is the result expression, we may need to evaluate
4888 // directly into the slot.
4889 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
4891 if (ov == resultExpr && ov->isRValue() && !forLValue &&
4892 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
4893 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
4894 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(),
4895 AlignmentSource::Decl);
4896 opaqueData = OVMA::bind(CGF, ov, LV);
4897 result.RV = slot.asRValue();
4899 // Otherwise, emit as normal.
4901 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
4903 // If this is the result, also evaluate the result now.
4904 if (ov == resultExpr) {
4906 result.LV = CGF.EmitLValue(ov);
4908 result.RV = CGF.EmitAnyExpr(ov, slot);
4912 opaques.push_back(opaqueData);
4914 // Otherwise, if the expression is the result, evaluate it
4915 // and remember the result.
4916 } else if (semantic == resultExpr) {
4918 result.LV = CGF.EmitLValue(semantic);
4920 result.RV = CGF.EmitAnyExpr(semantic, slot);
4922 // Otherwise, evaluate the expression in an ignored context.
4924 CGF.EmitIgnoredExpr(semantic);
4928 // Unbind all the opaques now.
4929 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
4930 opaques[i].unbind(CGF);
4935 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
4936 AggValueSlot slot) {
4937 return emitPseudoObjectExpr(*this, E, false, slot).RV;
4940 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
4941 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;