1 //===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This contains code to emit Expr nodes as LLVM code.
11 //===----------------------------------------------------------------------===//
15 #include "CGCleanup.h"
16 #include "CGDebugInfo.h"
17 #include "CGObjCRuntime.h"
18 #include "CGOpenMPRuntime.h"
19 #include "CGRecordLayout.h"
20 #include "CodeGenFunction.h"
21 #include "CodeGenModule.h"
22 #include "ConstantEmitter.h"
23 #include "TargetInfo.h"
24 #include "clang/AST/ASTContext.h"
25 #include "clang/AST/Attr.h"
26 #include "clang/AST/DeclObjC.h"
27 #include "clang/AST/NSAPI.h"
28 #include "clang/Basic/Builtins.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::FunctionCallee 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.getAddrAndTypeOfCXXStructor(
344 GlobalDecl(ReferenceTemporaryDtor, Dtor_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 llvm::Value *ArraySize) {
658 if (!sanitizePerformTypeCheck())
661 // Don't check pointers outside the default address space. The null check
662 // isn't correct, the object-size check isn't supported by LLVM, and we can't
663 // communicate the addresses to the runtime handler for the vptr check.
664 if (Ptr->getType()->getPointerAddressSpace())
667 // Don't check pointers to volatile data. The behavior here is implementation-
669 if (Ty.isVolatileQualified())
672 SanitizerScope SanScope(this);
674 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks;
675 llvm::BasicBlock *Done = nullptr;
677 // Quickly determine whether we have a pointer to an alloca. It's possible
678 // to skip null checks, and some alignment checks, for these pointers. This
679 // can reduce compile-time significantly.
681 dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCastsNoFollowAliases());
683 llvm::Value *True = llvm::ConstantInt::getTrue(getLLVMContext());
684 llvm::Value *IsNonNull = nullptr;
685 bool IsGuaranteedNonNull =
686 SkippedChecks.has(SanitizerKind::Null) || PtrToAlloca;
687 bool AllowNullPointers = isNullPointerAllowed(TCK);
688 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) &&
689 !IsGuaranteedNonNull) {
690 // The glvalue must not be an empty glvalue.
691 IsNonNull = Builder.CreateIsNotNull(Ptr);
693 // The IR builder can constant-fold the null check if the pointer points to
695 IsGuaranteedNonNull = IsNonNull == True;
697 // Skip the null check if the pointer is known to be non-null.
698 if (!IsGuaranteedNonNull) {
699 if (AllowNullPointers) {
700 // When performing pointer casts, it's OK if the value is null.
701 // Skip the remaining checks in that case.
702 Done = createBasicBlock("null");
703 llvm::BasicBlock *Rest = createBasicBlock("not.null");
704 Builder.CreateCondBr(IsNonNull, Rest, Done);
707 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null));
712 if (SanOpts.has(SanitizerKind::ObjectSize) &&
713 !SkippedChecks.has(SanitizerKind::ObjectSize) &&
714 !Ty->isIncompleteType()) {
715 uint64_t TySize = getContext().getTypeSizeInChars(Ty).getQuantity();
716 llvm::Value *Size = llvm::ConstantInt::get(IntPtrTy, TySize);
718 Size = Builder.CreateMul(Size, ArraySize);
720 // Degenerate case: new X[0] does not need an objectsize check.
721 llvm::Constant *ConstantSize = dyn_cast<llvm::Constant>(Size);
722 if (!ConstantSize || !ConstantSize->isNullValue()) {
723 // The glvalue must refer to a large enough storage region.
724 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
726 // FIXME: Get object address space
727 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
728 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
729 llvm::Value *Min = Builder.getFalse();
730 llvm::Value *NullIsUnknown = Builder.getFalse();
731 llvm::Value *Dynamic = Builder.getFalse();
732 llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy);
733 llvm::Value *LargeEnough = Builder.CreateICmpUGE(
734 Builder.CreateCall(F, {CastAddr, Min, NullIsUnknown, Dynamic}), Size);
735 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
739 uint64_t AlignVal = 0;
740 llvm::Value *PtrAsInt = nullptr;
742 if (SanOpts.has(SanitizerKind::Alignment) &&
743 !SkippedChecks.has(SanitizerKind::Alignment)) {
744 AlignVal = Alignment.getQuantity();
745 if (!Ty->isIncompleteType() && !AlignVal)
746 AlignVal = getContext().getTypeAlignInChars(Ty).getQuantity();
748 // The glvalue must be suitably aligned.
750 (!PtrToAlloca || PtrToAlloca->getAlignment() < AlignVal)) {
751 PtrAsInt = Builder.CreatePtrToInt(Ptr, IntPtrTy);
752 llvm::Value *Align = Builder.CreateAnd(
753 PtrAsInt, llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
754 llvm::Value *Aligned =
755 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
757 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment));
761 if (Checks.size() > 0) {
762 // Make sure we're not losing information. Alignment needs to be a power of
764 assert(!AlignVal || (uint64_t)1 << llvm::Log2_64(AlignVal) == AlignVal);
765 llvm::Constant *StaticData[] = {
766 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty),
767 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2_64(AlignVal) : 1),
768 llvm::ConstantInt::get(Int8Ty, TCK)};
769 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData,
770 PtrAsInt ? PtrAsInt : Ptr);
773 // If possible, check that the vptr indicates that there is a subobject of
774 // type Ty at offset zero within this object.
776 // C++11 [basic.life]p5,6:
777 // [For storage which does not refer to an object within its lifetime]
778 // The program has undefined behavior if:
779 // -- the [pointer or glvalue] is used to access a non-static data member
780 // or call a non-static member function
781 if (SanOpts.has(SanitizerKind::Vptr) &&
782 !SkippedChecks.has(SanitizerKind::Vptr) && isVptrCheckRequired(TCK, Ty)) {
783 // Ensure that the pointer is non-null before loading it. If there is no
784 // compile-time guarantee, reuse the run-time null check or emit a new one.
785 if (!IsGuaranteedNonNull) {
787 IsNonNull = Builder.CreateIsNotNull(Ptr);
789 Done = createBasicBlock("vptr.null");
790 llvm::BasicBlock *VptrNotNull = createBasicBlock("vptr.not.null");
791 Builder.CreateCondBr(IsNonNull, VptrNotNull, Done);
792 EmitBlock(VptrNotNull);
795 // Compute a hash of the mangled name of the type.
797 // FIXME: This is not guaranteed to be deterministic! Move to a
798 // fingerprinting mechanism once LLVM provides one. For the time
799 // being the implementation happens to be deterministic.
800 SmallString<64> MangledName;
801 llvm::raw_svector_ostream Out(MangledName);
802 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
805 // Blacklist based on the mangled type.
806 if (!CGM.getContext().getSanitizerBlacklist().isBlacklistedType(
807 SanitizerKind::Vptr, Out.str())) {
808 llvm::hash_code TypeHash = hash_value(Out.str());
810 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
811 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
812 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
813 Address VPtrAddr(Builder.CreateBitCast(Ptr, VPtrTy), getPointerAlign());
814 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
815 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
817 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
818 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
820 // Look the hash up in our cache.
821 const int CacheSize = 128;
822 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
823 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
824 "__ubsan_vptr_type_cache");
825 llvm::Value *Slot = Builder.CreateAnd(Hash,
826 llvm::ConstantInt::get(IntPtrTy,
828 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
829 llvm::Value *CacheVal =
830 Builder.CreateAlignedLoad(Builder.CreateInBoundsGEP(Cache, Indices),
833 // If the hash isn't in the cache, call a runtime handler to perform the
834 // hard work of checking whether the vptr is for an object of the right
835 // type. This will either fill in the cache and return, or produce a
837 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash);
838 llvm::Constant *StaticData[] = {
839 EmitCheckSourceLocation(Loc),
840 EmitCheckTypeDescriptor(Ty),
841 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
842 llvm::ConstantInt::get(Int8Ty, TCK)
844 llvm::Value *DynamicData[] = { Ptr, Hash };
845 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr),
846 SanitizerHandler::DynamicTypeCacheMiss, StaticData,
852 Builder.CreateBr(Done);
857 /// Determine whether this expression refers to a flexible array member in a
858 /// struct. We disable array bounds checks for such members.
859 static bool isFlexibleArrayMemberExpr(const Expr *E) {
860 // For compatibility with existing code, we treat arrays of length 0 or
861 // 1 as flexible array members.
862 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
863 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
864 if (CAT->getSize().ugt(1))
866 } else if (!isa<IncompleteArrayType>(AT))
869 E = E->IgnoreParens();
871 // A flexible array member must be the last member in the class.
872 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
873 // FIXME: If the base type of the member expr is not FD->getParent(),
874 // this should not be treated as a flexible array member access.
875 if (const auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
876 RecordDecl::field_iterator FI(
877 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
878 return ++FI == FD->getParent()->field_end();
880 } else if (const auto *IRE = dyn_cast<ObjCIvarRefExpr>(E)) {
881 return IRE->getDecl()->getNextIvar() == nullptr;
887 llvm::Value *CodeGenFunction::LoadPassedObjectSize(const Expr *E,
889 ASTContext &C = getContext();
890 uint64_t EltSize = C.getTypeSizeInChars(EltTy).getQuantity();
894 auto *ArrayDeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts());
898 auto *ParamDecl = dyn_cast<ParmVarDecl>(ArrayDeclRef->getDecl());
902 auto *POSAttr = ParamDecl->getAttr<PassObjectSizeAttr>();
906 // Don't load the size if it's a lower bound.
907 int POSType = POSAttr->getType();
908 if (POSType != 0 && POSType != 1)
911 // Find the implicit size parameter.
912 auto PassedSizeIt = SizeArguments.find(ParamDecl);
913 if (PassedSizeIt == SizeArguments.end())
916 const ImplicitParamDecl *PassedSizeDecl = PassedSizeIt->second;
917 assert(LocalDeclMap.count(PassedSizeDecl) && "Passed size not loadable");
918 Address AddrOfSize = LocalDeclMap.find(PassedSizeDecl)->second;
919 llvm::Value *SizeInBytes = EmitLoadOfScalar(AddrOfSize, /*Volatile=*/false,
920 C.getSizeType(), E->getExprLoc());
921 llvm::Value *SizeOfElement =
922 llvm::ConstantInt::get(SizeInBytes->getType(), EltSize);
923 return Builder.CreateUDiv(SizeInBytes, SizeOfElement);
926 /// If Base is known to point to the start of an array, return the length of
927 /// that array. Return 0 if the length cannot be determined.
928 static llvm::Value *getArrayIndexingBound(
929 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
930 // For the vector indexing extension, the bound is the number of elements.
931 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
932 IndexedType = Base->getType();
933 return CGF.Builder.getInt32(VT->getNumElements());
936 Base = Base->IgnoreParens();
938 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
939 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
940 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
941 IndexedType = CE->getSubExpr()->getType();
942 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
943 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
944 return CGF.Builder.getInt(CAT->getSize());
945 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
946 return CGF.getVLASize(VAT).NumElts;
947 // Ignore pass_object_size here. It's not applicable on decayed pointers.
951 QualType EltTy{Base->getType()->getPointeeOrArrayElementType(), 0};
952 if (llvm::Value *POS = CGF.LoadPassedObjectSize(Base, EltTy)) {
953 IndexedType = Base->getType();
960 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
961 llvm::Value *Index, QualType IndexType,
963 assert(SanOpts.has(SanitizerKind::ArrayBounds) &&
964 "should not be called unless adding bounds checks");
965 SanitizerScope SanScope(this);
967 QualType IndexedType;
968 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
972 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
973 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
974 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
976 llvm::Constant *StaticData[] = {
977 EmitCheckSourceLocation(E->getExprLoc()),
978 EmitCheckTypeDescriptor(IndexedType),
979 EmitCheckTypeDescriptor(IndexType)
981 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
982 : Builder.CreateICmpULE(IndexVal, BoundVal);
983 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds),
984 SanitizerHandler::OutOfBounds, StaticData, Index);
988 CodeGenFunction::ComplexPairTy CodeGenFunction::
989 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
990 bool isInc, bool isPre) {
991 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
993 llvm::Value *NextVal;
994 if (isa<llvm::IntegerType>(InVal.first->getType())) {
995 uint64_t AmountVal = isInc ? 1 : -1;
996 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
998 // Add the inc/dec to the real part.
999 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1001 QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
1002 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
1005 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
1007 // Add the inc/dec to the real part.
1008 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1011 ComplexPairTy IncVal(NextVal, InVal.second);
1013 // Store the updated result through the lvalue.
1014 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
1016 // If this is a postinc, return the value read from memory, otherwise use the
1018 return isPre ? IncVal : InVal;
1021 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E,
1022 CodeGenFunction *CGF) {
1023 // Bind VLAs in the cast type.
1024 if (CGF && E->getType()->isVariablyModifiedType())
1025 CGF->EmitVariablyModifiedType(E->getType());
1027 if (CGDebugInfo *DI = getModuleDebugInfo())
1028 DI->EmitExplicitCastType(E->getType());
1031 //===----------------------------------------------------------------------===//
1032 // LValue Expression Emission
1033 //===----------------------------------------------------------------------===//
1035 /// EmitPointerWithAlignment - Given an expression of pointer type, try to
1036 /// derive a more accurate bound on the alignment of the pointer.
1037 Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
1038 LValueBaseInfo *BaseInfo,
1039 TBAAAccessInfo *TBAAInfo) {
1040 // We allow this with ObjC object pointers because of fragile ABIs.
1041 assert(E->getType()->isPointerType() ||
1042 E->getType()->isObjCObjectPointerType());
1043 E = E->IgnoreParens();
1046 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
1047 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE))
1048 CGM.EmitExplicitCastExprType(ECE, this);
1050 switch (CE->getCastKind()) {
1051 // Non-converting casts (but not C's implicit conversion from void*).
1054 case CK_AddressSpaceConversion:
1055 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) {
1056 if (PtrTy->getPointeeType()->isVoidType())
1059 LValueBaseInfo InnerBaseInfo;
1060 TBAAAccessInfo InnerTBAAInfo;
1061 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(),
1064 if (BaseInfo) *BaseInfo = InnerBaseInfo;
1065 if (TBAAInfo) *TBAAInfo = InnerTBAAInfo;
1067 if (isa<ExplicitCastExpr>(CE)) {
1068 LValueBaseInfo TargetTypeBaseInfo;
1069 TBAAAccessInfo TargetTypeTBAAInfo;
1070 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(),
1071 &TargetTypeBaseInfo,
1072 &TargetTypeTBAAInfo);
1074 *TBAAInfo = CGM.mergeTBAAInfoForCast(*TBAAInfo,
1075 TargetTypeTBAAInfo);
1076 // If the source l-value is opaque, honor the alignment of the
1078 if (InnerBaseInfo.getAlignmentSource() != AlignmentSource::Decl) {
1080 BaseInfo->mergeForCast(TargetTypeBaseInfo);
1081 Addr = Address(Addr.getPointer(), Align);
1085 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast) &&
1086 CE->getCastKind() == CK_BitCast) {
1087 if (auto PT = E->getType()->getAs<PointerType>())
1088 EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr.getPointer(),
1090 CodeGenFunction::CFITCK_UnrelatedCast,
1093 return CE->getCastKind() != CK_AddressSpaceConversion
1094 ? Builder.CreateBitCast(Addr, ConvertType(E->getType()))
1095 : Builder.CreateAddrSpaceCast(Addr,
1096 ConvertType(E->getType()));
1100 // Array-to-pointer decay.
1101 case CK_ArrayToPointerDecay:
1102 return EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo, TBAAInfo);
1104 // Derived-to-base conversions.
1105 case CK_UncheckedDerivedToBase:
1106 case CK_DerivedToBase: {
1107 // TODO: Support accesses to members of base classes in TBAA. For now, we
1108 // conservatively pretend that the complete object is of the base class
1111 *TBAAInfo = CGM.getTBAAAccessInfo(E->getType());
1112 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), BaseInfo);
1113 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl();
1114 return GetAddressOfBaseClass(Addr, Derived,
1115 CE->path_begin(), CE->path_end(),
1116 ShouldNullCheckClassCastValue(CE),
1120 // TODO: Is there any reason to treat base-to-derived conversions
1128 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
1129 if (UO->getOpcode() == UO_AddrOf) {
1130 LValue LV = EmitLValue(UO->getSubExpr());
1131 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
1132 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo();
1133 return LV.getAddress();
1137 // TODO: conditional operators, comma.
1139 // Otherwise, use the alignment of the type.
1140 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(), BaseInfo,
1142 return Address(EmitScalarExpr(E), Align);
1145 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
1146 if (Ty->isVoidType())
1147 return RValue::get(nullptr);
1149 switch (getEvaluationKind(Ty)) {
1152 ConvertType(Ty->castAs<ComplexType>()->getElementType());
1153 llvm::Value *U = llvm::UndefValue::get(EltTy);
1154 return RValue::getComplex(std::make_pair(U, U));
1157 // If this is a use of an undefined aggregate type, the aggregate must have an
1158 // identifiable address. Just because the contents of the value are undefined
1159 // doesn't mean that the address can't be taken and compared.
1160 case TEK_Aggregate: {
1161 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
1162 return RValue::getAggregate(DestPtr);
1166 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
1168 llvm_unreachable("bad evaluation kind");
1171 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
1173 ErrorUnsupported(E, Name);
1174 return GetUndefRValue(E->getType());
1177 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
1179 ErrorUnsupported(E, Name);
1180 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
1181 return MakeAddrLValue(Address(llvm::UndefValue::get(Ty), CharUnits::One()),
1185 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) {
1186 const Expr *Base = Obj;
1187 while (!isa<CXXThisExpr>(Base)) {
1188 // The result of a dynamic_cast can be null.
1189 if (isa<CXXDynamicCastExpr>(Base))
1192 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
1193 Base = CE->getSubExpr();
1194 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) {
1195 Base = PE->getSubExpr();
1196 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) {
1197 if (UO->getOpcode() == UO_Extension)
1198 Base = UO->getSubExpr();
1208 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
1210 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E))
1211 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
1214 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) {
1215 SanitizerSet SkippedChecks;
1216 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
1217 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase());
1219 SkippedChecks.set(SanitizerKind::Alignment, true);
1220 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase()))
1221 SkippedChecks.set(SanitizerKind::Null, true);
1223 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(),
1224 E->getType(), LV.getAlignment(), SkippedChecks);
1229 /// EmitLValue - Emit code to compute a designator that specifies the location
1230 /// of the expression.
1232 /// This can return one of two things: a simple address or a bitfield reference.
1233 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
1234 /// an LLVM pointer type.
1236 /// If this returns a bitfield reference, nothing about the pointee type of the
1237 /// LLVM value is known: For example, it may not be a pointer to an integer.
1239 /// If this returns a normal address, and if the lvalue's C type is fixed size,
1240 /// this method guarantees that the returned pointer type will point to an LLVM
1241 /// type of the same size of the lvalue's type. If the lvalue has a variable
1242 /// length type, this is not possible.
1244 LValue CodeGenFunction::EmitLValue(const Expr *E) {
1245 ApplyDebugLocation DL(*this, E);
1246 switch (E->getStmtClass()) {
1247 default: return EmitUnsupportedLValue(E, "l-value expression");
1249 case Expr::ObjCPropertyRefExprClass:
1250 llvm_unreachable("cannot emit a property reference directly");
1252 case Expr::ObjCSelectorExprClass:
1253 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
1254 case Expr::ObjCIsaExprClass:
1255 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
1256 case Expr::BinaryOperatorClass:
1257 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
1258 case Expr::CompoundAssignOperatorClass: {
1259 QualType Ty = E->getType();
1260 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1261 Ty = AT->getValueType();
1262 if (!Ty->isAnyComplexType())
1263 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1264 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1266 case Expr::CallExprClass:
1267 case Expr::CXXMemberCallExprClass:
1268 case Expr::CXXOperatorCallExprClass:
1269 case Expr::UserDefinedLiteralClass:
1270 return EmitCallExprLValue(cast<CallExpr>(E));
1271 case Expr::VAArgExprClass:
1272 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
1273 case Expr::DeclRefExprClass:
1274 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
1275 case Expr::ConstantExprClass:
1276 return EmitLValue(cast<ConstantExpr>(E)->getSubExpr());
1277 case Expr::ParenExprClass:
1278 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
1279 case Expr::GenericSelectionExprClass:
1280 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
1281 case Expr::PredefinedExprClass:
1282 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
1283 case Expr::StringLiteralClass:
1284 return EmitStringLiteralLValue(cast<StringLiteral>(E));
1285 case Expr::ObjCEncodeExprClass:
1286 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
1287 case Expr::PseudoObjectExprClass:
1288 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
1289 case Expr::InitListExprClass:
1290 return EmitInitListLValue(cast<InitListExpr>(E));
1291 case Expr::CXXTemporaryObjectExprClass:
1292 case Expr::CXXConstructExprClass:
1293 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
1294 case Expr::CXXBindTemporaryExprClass:
1295 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
1296 case Expr::CXXUuidofExprClass:
1297 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
1298 case Expr::LambdaExprClass:
1299 return EmitAggExprToLValue(E);
1301 case Expr::ExprWithCleanupsClass: {
1302 const auto *cleanups = cast<ExprWithCleanups>(E);
1303 enterFullExpression(cleanups);
1304 RunCleanupsScope Scope(*this);
1305 LValue LV = EmitLValue(cleanups->getSubExpr());
1306 if (LV.isSimple()) {
1307 // Defend against branches out of gnu statement expressions surrounded by
1309 llvm::Value *V = LV.getPointer();
1310 Scope.ForceCleanup({&V});
1311 return LValue::MakeAddr(Address(V, LV.getAlignment()), LV.getType(),
1312 getContext(), LV.getBaseInfo(), LV.getTBAAInfo());
1314 // FIXME: Is it possible to create an ExprWithCleanups that produces a
1315 // bitfield lvalue or some other non-simple lvalue?
1319 case Expr::CXXDefaultArgExprClass: {
1320 auto *DAE = cast<CXXDefaultArgExpr>(E);
1321 CXXDefaultArgExprScope Scope(*this, DAE);
1322 return EmitLValue(DAE->getExpr());
1324 case Expr::CXXDefaultInitExprClass: {
1325 auto *DIE = cast<CXXDefaultInitExpr>(E);
1326 CXXDefaultInitExprScope Scope(*this, DIE);
1327 return EmitLValue(DIE->getExpr());
1329 case Expr::CXXTypeidExprClass:
1330 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
1332 case Expr::ObjCMessageExprClass:
1333 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
1334 case Expr::ObjCIvarRefExprClass:
1335 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
1336 case Expr::StmtExprClass:
1337 return EmitStmtExprLValue(cast<StmtExpr>(E));
1338 case Expr::UnaryOperatorClass:
1339 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
1340 case Expr::ArraySubscriptExprClass:
1341 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
1342 case Expr::OMPArraySectionExprClass:
1343 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E));
1344 case Expr::ExtVectorElementExprClass:
1345 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
1346 case Expr::MemberExprClass:
1347 return EmitMemberExpr(cast<MemberExpr>(E));
1348 case Expr::CompoundLiteralExprClass:
1349 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
1350 case Expr::ConditionalOperatorClass:
1351 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
1352 case Expr::BinaryConditionalOperatorClass:
1353 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
1354 case Expr::ChooseExprClass:
1355 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
1356 case Expr::OpaqueValueExprClass:
1357 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
1358 case Expr::SubstNonTypeTemplateParmExprClass:
1359 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
1360 case Expr::ImplicitCastExprClass:
1361 case Expr::CStyleCastExprClass:
1362 case Expr::CXXFunctionalCastExprClass:
1363 case Expr::CXXStaticCastExprClass:
1364 case Expr::CXXDynamicCastExprClass:
1365 case Expr::CXXReinterpretCastExprClass:
1366 case Expr::CXXConstCastExprClass:
1367 case Expr::ObjCBridgedCastExprClass:
1368 return EmitCastLValue(cast<CastExpr>(E));
1370 case Expr::MaterializeTemporaryExprClass:
1371 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
1373 case Expr::CoawaitExprClass:
1374 return EmitCoawaitLValue(cast<CoawaitExpr>(E));
1375 case Expr::CoyieldExprClass:
1376 return EmitCoyieldLValue(cast<CoyieldExpr>(E));
1380 /// Given an object of the given canonical type, can we safely copy a
1381 /// value out of it based on its initializer?
1382 static bool isConstantEmittableObjectType(QualType type) {
1383 assert(type.isCanonical());
1384 assert(!type->isReferenceType());
1386 // Must be const-qualified but non-volatile.
1387 Qualifiers qs = type.getLocalQualifiers();
1388 if (!qs.hasConst() || qs.hasVolatile()) return false;
1390 // Otherwise, all object types satisfy this except C++ classes with
1391 // mutable subobjects or non-trivial copy/destroy behavior.
1392 if (const auto *RT = dyn_cast<RecordType>(type))
1393 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1394 if (RD->hasMutableFields() || !RD->isTrivial())
1400 /// Can we constant-emit a load of a reference to a variable of the
1401 /// given type? This is different from predicates like
1402 /// Decl::mightBeUsableInConstantExpressions because we do want it to apply
1403 /// in situations that don't necessarily satisfy the language's rules
1404 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
1405 /// to do this with const float variables even if those variables
1406 /// aren't marked 'constexpr'.
1407 enum ConstantEmissionKind {
1409 CEK_AsReferenceOnly,
1410 CEK_AsValueOrReference,
1413 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
1414 type = type.getCanonicalType();
1415 if (const auto *ref = dyn_cast<ReferenceType>(type)) {
1416 if (isConstantEmittableObjectType(ref->getPointeeType()))
1417 return CEK_AsValueOrReference;
1418 return CEK_AsReferenceOnly;
1420 if (isConstantEmittableObjectType(type))
1421 return CEK_AsValueOnly;
1425 /// Try to emit a reference to the given value without producing it as
1426 /// an l-value. This is just an optimization, but it avoids us needing
1427 /// to emit global copies of variables if they're named without triggering
1428 /// a formal use in a context where we can't emit a direct reference to them,
1429 /// for instance if a block or lambda or a member of a local class uses a
1430 /// const int variable or constexpr variable from an enclosing function.
1431 CodeGenFunction::ConstantEmission
1432 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
1433 ValueDecl *value = refExpr->getDecl();
1435 // The value needs to be an enum constant or a constant variable.
1436 ConstantEmissionKind CEK;
1437 if (isa<ParmVarDecl>(value)) {
1439 } else if (auto *var = dyn_cast<VarDecl>(value)) {
1440 CEK = checkVarTypeForConstantEmission(var->getType());
1441 } else if (isa<EnumConstantDecl>(value)) {
1442 CEK = CEK_AsValueOnly;
1446 if (CEK == CEK_None) return ConstantEmission();
1448 Expr::EvalResult result;
1449 bool resultIsReference;
1450 QualType resultType;
1452 // It's best to evaluate all the way as an r-value if that's permitted.
1453 if (CEK != CEK_AsReferenceOnly &&
1454 refExpr->EvaluateAsRValue(result, getContext())) {
1455 resultIsReference = false;
1456 resultType = refExpr->getType();
1458 // Otherwise, try to evaluate as an l-value.
1459 } else if (CEK != CEK_AsValueOnly &&
1460 refExpr->EvaluateAsLValue(result, getContext())) {
1461 resultIsReference = true;
1462 resultType = value->getType();
1466 return ConstantEmission();
1469 // In any case, if the initializer has side-effects, abandon ship.
1470 if (result.HasSideEffects)
1471 return ConstantEmission();
1473 // Emit as a constant.
1474 auto C = ConstantEmitter(*this).emitAbstract(refExpr->getLocation(),
1475 result.Val, resultType);
1477 // Make sure we emit a debug reference to the global variable.
1478 // This should probably fire even for
1479 if (isa<VarDecl>(value)) {
1480 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
1481 EmitDeclRefExprDbgValue(refExpr, result.Val);
1483 assert(isa<EnumConstantDecl>(value));
1484 EmitDeclRefExprDbgValue(refExpr, result.Val);
1487 // If we emitted a reference constant, we need to dereference that.
1488 if (resultIsReference)
1489 return ConstantEmission::forReference(C);
1491 return ConstantEmission::forValue(C);
1494 static DeclRefExpr *tryToConvertMemberExprToDeclRefExpr(CodeGenFunction &CGF,
1495 const MemberExpr *ME) {
1496 if (auto *VD = dyn_cast<VarDecl>(ME->getMemberDecl())) {
1497 // Try to emit static variable member expressions as DREs.
1498 return DeclRefExpr::Create(
1499 CGF.getContext(), NestedNameSpecifierLoc(), SourceLocation(), VD,
1500 /*RefersToEnclosingVariableOrCapture=*/false, ME->getExprLoc(),
1501 ME->getType(), ME->getValueKind(), nullptr, nullptr, ME->isNonOdrUse());
1506 CodeGenFunction::ConstantEmission
1507 CodeGenFunction::tryEmitAsConstant(const MemberExpr *ME) {
1508 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, ME))
1509 return tryEmitAsConstant(DRE);
1510 return ConstantEmission();
1513 llvm::Value *CodeGenFunction::emitScalarConstant(
1514 const CodeGenFunction::ConstantEmission &Constant, Expr *E) {
1515 assert(Constant && "not a constant");
1516 if (Constant.isReference())
1517 return EmitLoadOfLValue(Constant.getReferenceLValue(*this, E),
1520 return Constant.getValue();
1523 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1524 SourceLocation Loc) {
1525 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
1526 lvalue.getType(), Loc, lvalue.getBaseInfo(),
1527 lvalue.getTBAAInfo(), lvalue.isNontemporal());
1530 static bool hasBooleanRepresentation(QualType Ty) {
1531 if (Ty->isBooleanType())
1534 if (const EnumType *ET = Ty->getAs<EnumType>())
1535 return ET->getDecl()->getIntegerType()->isBooleanType();
1537 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1538 return hasBooleanRepresentation(AT->getValueType());
1543 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1544 llvm::APInt &Min, llvm::APInt &End,
1545 bool StrictEnums, bool IsBool) {
1546 const EnumType *ET = Ty->getAs<EnumType>();
1547 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1548 ET && !ET->getDecl()->isFixed();
1549 if (!IsBool && !IsRegularCPlusPlusEnum)
1553 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1554 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1556 const EnumDecl *ED = ET->getDecl();
1557 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1558 unsigned Bitwidth = LTy->getScalarSizeInBits();
1559 unsigned NumNegativeBits = ED->getNumNegativeBits();
1560 unsigned NumPositiveBits = ED->getNumPositiveBits();
1562 if (NumNegativeBits) {
1563 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1564 assert(NumBits <= Bitwidth);
1565 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1568 assert(NumPositiveBits <= Bitwidth);
1569 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1570 Min = llvm::APInt(Bitwidth, 0);
1576 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1577 llvm::APInt Min, End;
1578 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums,
1579 hasBooleanRepresentation(Ty)))
1582 llvm::MDBuilder MDHelper(getLLVMContext());
1583 return MDHelper.createRange(Min, End);
1586 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
1587 SourceLocation Loc) {
1588 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool);
1589 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum);
1590 if (!HasBoolCheck && !HasEnumCheck)
1593 bool IsBool = hasBooleanRepresentation(Ty) ||
1594 NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
1595 bool NeedsBoolCheck = HasBoolCheck && IsBool;
1596 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>();
1597 if (!NeedsBoolCheck && !NeedsEnumCheck)
1600 // Single-bit booleans don't need to be checked. Special-case this to avoid
1601 // a bit width mismatch when handling bitfield values. This is handled by
1602 // EmitFromMemory for the non-bitfield case.
1604 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1)
1607 llvm::APInt Min, End;
1608 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool))
1611 auto &Ctx = getLLVMContext();
1612 SanitizerScope SanScope(this);
1616 Check = Builder.CreateICmpULE(Value, llvm::ConstantInt::get(Ctx, End));
1618 llvm::Value *Upper =
1619 Builder.CreateICmpSLE(Value, llvm::ConstantInt::get(Ctx, End));
1620 llvm::Value *Lower =
1621 Builder.CreateICmpSGE(Value, llvm::ConstantInt::get(Ctx, Min));
1622 Check = Builder.CreateAnd(Upper, Lower);
1624 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc),
1625 EmitCheckTypeDescriptor(Ty)};
1626 SanitizerMask Kind =
1627 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
1628 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue,
1629 StaticArgs, EmitCheckValue(Value));
1633 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
1636 LValueBaseInfo BaseInfo,
1637 TBAAAccessInfo TBAAInfo,
1638 bool isNontemporal) {
1639 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1640 // For better performance, handle vector loads differently.
1641 if (Ty->isVectorType()) {
1642 const llvm::Type *EltTy = Addr.getElementType();
1644 const auto *VTy = cast<llvm::VectorType>(EltTy);
1646 // Handle vectors of size 3 like size 4 for better performance.
1647 if (VTy->getNumElements() == 3) {
1649 // Bitcast to vec4 type.
1650 llvm::VectorType *vec4Ty =
1651 llvm::VectorType::get(VTy->getElementType(), 4);
1652 Address Cast = Builder.CreateElementBitCast(Addr, vec4Ty, "castToVec4");
1654 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1656 // Shuffle vector to get vec3.
1657 V = Builder.CreateShuffleVector(V, llvm::UndefValue::get(vec4Ty),
1658 {0, 1, 2}, "extractVec");
1659 return EmitFromMemory(V, Ty);
1664 // Atomic operations have to be done on integral types.
1665 LValue AtomicLValue =
1666 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1667 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) {
1668 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal();
1671 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
1672 if (isNontemporal) {
1673 llvm::MDNode *Node = llvm::MDNode::get(
1674 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1675 Load->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1678 CGM.DecorateInstructionWithTBAA(Load, TBAAInfo);
1680 if (EmitScalarRangeCheck(Load, Ty, Loc)) {
1681 // In order to prevent the optimizer from throwing away the check, don't
1682 // attach range metadata to the load.
1683 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1684 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1685 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1687 return EmitFromMemory(Load, Ty);
1690 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1691 // Bool has a different representation in memory than in registers.
1692 if (hasBooleanRepresentation(Ty)) {
1693 // This should really always be an i1, but sometimes it's already
1694 // an i8, and it's awkward to track those cases down.
1695 if (Value->getType()->isIntegerTy(1))
1696 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1697 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1698 "wrong value rep of bool");
1704 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1705 // Bool has a different representation in memory than in registers.
1706 if (hasBooleanRepresentation(Ty)) {
1707 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1708 "wrong value rep of bool");
1709 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1715 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
1716 bool Volatile, QualType Ty,
1717 LValueBaseInfo BaseInfo,
1718 TBAAAccessInfo TBAAInfo,
1719 bool isInit, bool isNontemporal) {
1720 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1721 // Handle vectors differently to get better performance.
1722 if (Ty->isVectorType()) {
1723 llvm::Type *SrcTy = Value->getType();
1724 auto *VecTy = dyn_cast<llvm::VectorType>(SrcTy);
1725 // Handle vec3 special.
1726 if (VecTy && VecTy->getNumElements() == 3) {
1727 // Our source is a vec3, do a shuffle vector to make it a vec4.
1728 llvm::Constant *Mask[] = {Builder.getInt32(0), Builder.getInt32(1),
1729 Builder.getInt32(2),
1730 llvm::UndefValue::get(Builder.getInt32Ty())};
1731 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1732 Value = Builder.CreateShuffleVector(Value, llvm::UndefValue::get(VecTy),
1733 MaskV, "extractVec");
1734 SrcTy = llvm::VectorType::get(VecTy->getElementType(), 4);
1736 if (Addr.getElementType() != SrcTy) {
1737 Addr = Builder.CreateElementBitCast(Addr, SrcTy, "storetmp");
1742 Value = EmitToMemory(Value, Ty);
1744 LValue AtomicLValue =
1745 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1746 if (Ty->isAtomicType() ||
1747 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) {
1748 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit);
1752 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1753 if (isNontemporal) {
1754 llvm::MDNode *Node =
1755 llvm::MDNode::get(Store->getContext(),
1756 llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1757 Store->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1760 CGM.DecorateInstructionWithTBAA(Store, TBAAInfo);
1763 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1765 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
1766 lvalue.getType(), lvalue.getBaseInfo(),
1767 lvalue.getTBAAInfo(), isInit, lvalue.isNontemporal());
1770 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1771 /// method emits the address of the lvalue, then loads the result as an rvalue,
1772 /// returning the rvalue.
1773 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1774 if (LV.isObjCWeak()) {
1775 // load of a __weak object.
1776 Address AddrWeakObj = LV.getAddress();
1777 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1780 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1781 // In MRC mode, we do a load+autorelease.
1782 if (!getLangOpts().ObjCAutoRefCount) {
1783 return RValue::get(EmitARCLoadWeak(LV.getAddress()));
1786 // In ARC mode, we load retained and then consume the value.
1787 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
1788 Object = EmitObjCConsumeObject(LV.getType(), Object);
1789 return RValue::get(Object);
1792 if (LV.isSimple()) {
1793 assert(!LV.getType()->isFunctionType());
1795 // Everything needs a load.
1796 return RValue::get(EmitLoadOfScalar(LV, Loc));
1799 if (LV.isVectorElt()) {
1800 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(),
1801 LV.isVolatileQualified());
1802 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1806 // If this is a reference to a subset of the elements of a vector, either
1807 // shuffle the input or extract/insert them as appropriate.
1808 if (LV.isExtVectorElt())
1809 return EmitLoadOfExtVectorElementLValue(LV);
1811 // Global Register variables always invoke intrinsics
1812 if (LV.isGlobalReg())
1813 return EmitLoadOfGlobalRegLValue(LV);
1815 assert(LV.isBitField() && "Unknown LValue type!");
1816 return EmitLoadOfBitfieldLValue(LV, Loc);
1819 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
1820 SourceLocation Loc) {
1821 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1823 // Get the output type.
1824 llvm::Type *ResLTy = ConvertType(LV.getType());
1826 Address Ptr = LV.getBitFieldAddress();
1827 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load");
1829 if (Info.IsSigned) {
1830 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1831 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1833 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1834 if (Info.Offset + HighBits)
1835 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1838 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1839 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1840 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1844 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1845 EmitScalarRangeCheck(Val, LV.getType(), Loc);
1846 return RValue::get(Val);
1849 // If this is a reference to a subset of the elements of a vector, create an
1850 // appropriate shufflevector.
1851 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1852 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(),
1853 LV.isVolatileQualified());
1855 const llvm::Constant *Elts = LV.getExtVectorElts();
1857 // If the result of the expression is a non-vector type, we must be extracting
1858 // a single element. Just codegen as an extractelement.
1859 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1861 unsigned InIdx = getAccessedFieldNo(0, Elts);
1862 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1863 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1866 // Always use shuffle vector to try to retain the original program structure
1867 unsigned NumResultElts = ExprVT->getNumElements();
1869 SmallVector<llvm::Constant*, 4> Mask;
1870 for (unsigned i = 0; i != NumResultElts; ++i)
1871 Mask.push_back(Builder.getInt32(getAccessedFieldNo(i, Elts)));
1873 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1874 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1876 return RValue::get(Vec);
1879 /// Generates lvalue for partial ext_vector access.
1880 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) {
1881 Address VectorAddress = LV.getExtVectorAddress();
1882 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1883 QualType EQT = ExprVT->getElementType();
1884 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT);
1886 Address CastToPointerElement =
1887 Builder.CreateElementBitCast(VectorAddress, VectorElementTy,
1888 "conv.ptr.element");
1890 const llvm::Constant *Elts = LV.getExtVectorElts();
1891 unsigned ix = getAccessedFieldNo(0, Elts);
1893 Address VectorBasePtrPlusIx =
1894 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix,
1897 return VectorBasePtrPlusIx;
1900 /// Load of global gamed gegisters are always calls to intrinsics.
1901 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
1902 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
1903 "Bad type for register variable");
1904 llvm::MDNode *RegName = cast<llvm::MDNode>(
1905 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata());
1907 // We accept integer and pointer types only
1908 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
1909 llvm::Type *Ty = OrigTy;
1910 if (OrigTy->isPointerTy())
1911 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1912 llvm::Type *Types[] = { Ty };
1914 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
1915 llvm::Value *Call = Builder.CreateCall(
1916 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName));
1917 if (OrigTy->isPointerTy())
1918 Call = Builder.CreateIntToPtr(Call, OrigTy);
1919 return RValue::get(Call);
1923 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
1924 /// lvalue, where both are guaranteed to the have the same type, and that type
1926 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
1928 if (!Dst.isSimple()) {
1929 if (Dst.isVectorElt()) {
1930 // Read/modify/write the vector, inserting the new element.
1931 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(),
1932 Dst.isVolatileQualified());
1933 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
1934 Dst.getVectorIdx(), "vecins");
1935 Builder.CreateStore(Vec, Dst.getVectorAddress(),
1936 Dst.isVolatileQualified());
1940 // If this is an update of extended vector elements, insert them as
1942 if (Dst.isExtVectorElt())
1943 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
1945 if (Dst.isGlobalReg())
1946 return EmitStoreThroughGlobalRegLValue(Src, Dst);
1948 assert(Dst.isBitField() && "Unknown LValue type");
1949 return EmitStoreThroughBitfieldLValue(Src, Dst);
1952 // There's special magic for assigning into an ARC-qualified l-value.
1953 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
1955 case Qualifiers::OCL_None:
1956 llvm_unreachable("present but none");
1958 case Qualifiers::OCL_ExplicitNone:
1962 case Qualifiers::OCL_Strong:
1964 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal()));
1967 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
1970 case Qualifiers::OCL_Weak:
1972 // Initialize and then skip the primitive store.
1973 EmitARCInitWeak(Dst.getAddress(), Src.getScalarVal());
1975 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true);
1978 case Qualifiers::OCL_Autoreleasing:
1979 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
1980 Src.getScalarVal()));
1981 // fall into the normal path
1986 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
1987 // load of a __weak object.
1988 Address LvalueDst = Dst.getAddress();
1989 llvm::Value *src = Src.getScalarVal();
1990 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
1994 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
1995 // load of a __strong object.
1996 Address LvalueDst = Dst.getAddress();
1997 llvm::Value *src = Src.getScalarVal();
1998 if (Dst.isObjCIvar()) {
1999 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
2000 llvm::Type *ResultType = IntPtrTy;
2001 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp());
2002 llvm::Value *RHS = dst.getPointer();
2003 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
2005 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType,
2006 "sub.ptr.lhs.cast");
2007 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
2008 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
2010 } else if (Dst.isGlobalObjCRef()) {
2011 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
2012 Dst.isThreadLocalRef());
2015 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
2019 assert(Src.isScalar() && "Can't emit an agg store with this method");
2020 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
2023 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
2024 llvm::Value **Result) {
2025 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
2026 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
2027 Address Ptr = Dst.getBitFieldAddress();
2029 // Get the source value, truncated to the width of the bit-field.
2030 llvm::Value *SrcVal = Src.getScalarVal();
2032 // Cast the source to the storage type and shift it into place.
2033 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(),
2034 /*isSigned=*/false);
2035 llvm::Value *MaskedVal = SrcVal;
2037 // See if there are other bits in the bitfield's storage we'll need to load
2038 // and mask together with source before storing.
2039 if (Info.StorageSize != Info.Size) {
2040 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
2042 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load");
2044 // Mask the source value as needed.
2045 if (!hasBooleanRepresentation(Dst.getType()))
2046 SrcVal = Builder.CreateAnd(SrcVal,
2047 llvm::APInt::getLowBitsSet(Info.StorageSize,
2052 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
2054 // Mask out the original value.
2055 Val = Builder.CreateAnd(Val,
2056 ~llvm::APInt::getBitsSet(Info.StorageSize,
2058 Info.Offset + Info.Size),
2061 // Or together the unchanged values and the source value.
2062 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
2064 assert(Info.Offset == 0);
2067 // Write the new value back out.
2068 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified());
2070 // Return the new value of the bit-field, if requested.
2072 llvm::Value *ResultVal = MaskedVal;
2074 // Sign extend the value if needed.
2075 if (Info.IsSigned) {
2076 assert(Info.Size <= Info.StorageSize);
2077 unsigned HighBits = Info.StorageSize - Info.Size;
2079 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
2080 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
2084 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
2086 *Result = EmitFromMemory(ResultVal, Dst.getType());
2090 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
2092 // This access turns into a read/modify/write of the vector. Load the input
2094 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddress(),
2095 Dst.isVolatileQualified());
2096 const llvm::Constant *Elts = Dst.getExtVectorElts();
2098 llvm::Value *SrcVal = Src.getScalarVal();
2100 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
2101 unsigned NumSrcElts = VTy->getNumElements();
2102 unsigned NumDstElts = Vec->getType()->getVectorNumElements();
2103 if (NumDstElts == NumSrcElts) {
2104 // Use shuffle vector is the src and destination are the same number of
2105 // elements and restore the vector mask since it is on the side it will be
2107 SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
2108 for (unsigned i = 0; i != NumSrcElts; ++i)
2109 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i);
2111 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
2112 Vec = Builder.CreateShuffleVector(SrcVal,
2113 llvm::UndefValue::get(Vec->getType()),
2115 } else if (NumDstElts > NumSrcElts) {
2116 // Extended the source vector to the same length and then shuffle it
2117 // into the destination.
2118 // FIXME: since we're shuffling with undef, can we just use the indices
2119 // into that? This could be simpler.
2120 SmallVector<llvm::Constant*, 4> ExtMask;
2121 for (unsigned i = 0; i != NumSrcElts; ++i)
2122 ExtMask.push_back(Builder.getInt32(i));
2123 ExtMask.resize(NumDstElts, llvm::UndefValue::get(Int32Ty));
2124 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
2125 llvm::Value *ExtSrcVal =
2126 Builder.CreateShuffleVector(SrcVal,
2127 llvm::UndefValue::get(SrcVal->getType()),
2130 SmallVector<llvm::Constant*, 4> Mask;
2131 for (unsigned i = 0; i != NumDstElts; ++i)
2132 Mask.push_back(Builder.getInt32(i));
2134 // When the vector size is odd and .odd or .hi is used, the last element
2135 // of the Elts constant array will be one past the size of the vector.
2136 // Ignore the last element here, if it is greater than the mask size.
2137 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
2140 // modify when what gets shuffled in
2141 for (unsigned i = 0; i != NumSrcElts; ++i)
2142 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i+NumDstElts);
2143 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
2144 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV);
2146 // We should never shorten the vector
2147 llvm_unreachable("unexpected shorten vector length");
2150 // If the Src is a scalar (not a vector) it must be updating one element.
2151 unsigned InIdx = getAccessedFieldNo(0, Elts);
2152 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
2153 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
2156 Builder.CreateStore(Vec, Dst.getExtVectorAddress(),
2157 Dst.isVolatileQualified());
2160 /// Store of global named registers are always calls to intrinsics.
2161 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
2162 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
2163 "Bad type for register variable");
2164 llvm::MDNode *RegName = cast<llvm::MDNode>(
2165 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata());
2166 assert(RegName && "Register LValue is not metadata");
2168 // We accept integer and pointer types only
2169 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
2170 llvm::Type *Ty = OrigTy;
2171 if (OrigTy->isPointerTy())
2172 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
2173 llvm::Type *Types[] = { Ty };
2175 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
2176 llvm::Value *Value = Src.getScalarVal();
2177 if (OrigTy->isPointerTy())
2178 Value = Builder.CreatePtrToInt(Value, Ty);
2180 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value});
2183 // setObjCGCLValueClass - sets class of the lvalue for the purpose of
2184 // generating write-barries API. It is currently a global, ivar,
2186 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
2188 bool IsMemberAccess=false) {
2189 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
2192 if (isa<ObjCIvarRefExpr>(E)) {
2193 QualType ExpTy = E->getType();
2194 if (IsMemberAccess && ExpTy->isPointerType()) {
2195 // If ivar is a structure pointer, assigning to field of
2196 // this struct follows gcc's behavior and makes it a non-ivar
2197 // writer-barrier conservatively.
2198 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
2199 if (ExpTy->isRecordType()) {
2200 LV.setObjCIvar(false);
2204 LV.setObjCIvar(true);
2205 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
2206 LV.setBaseIvarExp(Exp->getBase());
2207 LV.setObjCArray(E->getType()->isArrayType());
2211 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
2212 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
2213 if (VD->hasGlobalStorage()) {
2214 LV.setGlobalObjCRef(true);
2215 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
2218 LV.setObjCArray(E->getType()->isArrayType());
2222 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
2223 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2227 if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
2228 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2229 if (LV.isObjCIvar()) {
2230 // If cast is to a structure pointer, follow gcc's behavior and make it
2231 // a non-ivar write-barrier.
2232 QualType ExpTy = E->getType();
2233 if (ExpTy->isPointerType())
2234 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
2235 if (ExpTy->isRecordType())
2236 LV.setObjCIvar(false);
2241 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
2242 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
2246 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
2247 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2251 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
2252 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2256 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
2257 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2261 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
2262 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
2263 if (LV.isObjCIvar() && !LV.isObjCArray())
2264 // Using array syntax to assigning to what an ivar points to is not
2265 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
2266 LV.setObjCIvar(false);
2267 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
2268 // Using array syntax to assigning to what global points to is not
2269 // same as assigning to the global itself. {id *G;} G[i] = 0;
2270 LV.setGlobalObjCRef(false);
2274 if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
2275 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
2276 // We don't know if member is an 'ivar', but this flag is looked at
2277 // only in the context of LV.isObjCIvar().
2278 LV.setObjCArray(E->getType()->isArrayType());
2283 static llvm::Value *
2284 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
2285 llvm::Value *V, llvm::Type *IRType,
2286 StringRef Name = StringRef()) {
2287 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
2288 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
2291 static LValue EmitThreadPrivateVarDeclLValue(
2292 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr,
2293 llvm::Type *RealVarTy, SourceLocation Loc) {
2294 Addr = CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc);
2295 Addr = CGF.Builder.CreateElementBitCast(Addr, RealVarTy);
2296 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2299 static Address emitDeclTargetVarDeclLValue(CodeGenFunction &CGF,
2300 const VarDecl *VD, QualType T) {
2301 llvm::Optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
2302 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD);
2303 // Return an invalid address if variable is MT_To and unified
2304 // memory is not enabled. For all other cases: MT_Link and
2305 // MT_To with unified memory, return a valid address.
2306 if (!Res || (*Res == OMPDeclareTargetDeclAttr::MT_To &&
2307 !CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory()))
2308 return Address::invalid();
2309 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) ||
2310 (*Res == OMPDeclareTargetDeclAttr::MT_To &&
2311 CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) &&
2312 "Expected link clause OR to clause with unified memory enabled.");
2313 QualType PtrTy = CGF.getContext().getPointerType(VD->getType());
2314 Address Addr = CGF.CGM.getOpenMPRuntime().getAddrOfDeclareTargetVar(VD);
2315 return CGF.EmitLoadOfPointer(Addr, PtrTy->castAs<PointerType>());
2319 CodeGenFunction::EmitLoadOfReference(LValue RefLVal,
2320 LValueBaseInfo *PointeeBaseInfo,
2321 TBAAAccessInfo *PointeeTBAAInfo) {
2322 llvm::LoadInst *Load = Builder.CreateLoad(RefLVal.getAddress(),
2323 RefLVal.isVolatile());
2324 CGM.DecorateInstructionWithTBAA(Load, RefLVal.getTBAAInfo());
2326 CharUnits Align = getNaturalTypeAlignment(RefLVal.getType()->getPointeeType(),
2327 PointeeBaseInfo, PointeeTBAAInfo,
2328 /* forPointeeType= */ true);
2329 return Address(Load, Align);
2332 LValue CodeGenFunction::EmitLoadOfReferenceLValue(LValue RefLVal) {
2333 LValueBaseInfo PointeeBaseInfo;
2334 TBAAAccessInfo PointeeTBAAInfo;
2335 Address PointeeAddr = EmitLoadOfReference(RefLVal, &PointeeBaseInfo,
2337 return MakeAddrLValue(PointeeAddr, RefLVal.getType()->getPointeeType(),
2338 PointeeBaseInfo, PointeeTBAAInfo);
2341 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr,
2342 const PointerType *PtrTy,
2343 LValueBaseInfo *BaseInfo,
2344 TBAAAccessInfo *TBAAInfo) {
2345 llvm::Value *Addr = Builder.CreateLoad(Ptr);
2346 return Address(Addr, getNaturalTypeAlignment(PtrTy->getPointeeType(),
2348 /*forPointeeType=*/true));
2351 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr,
2352 const PointerType *PtrTy) {
2353 LValueBaseInfo BaseInfo;
2354 TBAAAccessInfo TBAAInfo;
2355 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo, &TBAAInfo);
2356 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo, TBAAInfo);
2359 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
2360 const Expr *E, const VarDecl *VD) {
2361 QualType T = E->getType();
2363 // If it's thread_local, emit a call to its wrapper function instead.
2364 if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
2365 CGF.CGM.getCXXABI().usesThreadWrapperFunction())
2366 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
2367 // Check if the variable is marked as declare target with link clause in
2369 if (CGF.getLangOpts().OpenMPIsDevice) {
2370 Address Addr = emitDeclTargetVarDeclLValue(CGF, VD, T);
2372 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2375 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
2376 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
2377 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
2378 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
2379 Address Addr(V, Alignment);
2380 // Emit reference to the private copy of the variable if it is an OpenMP
2381 // threadprivate variable.
2382 if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd &&
2383 VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2384 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
2387 LValue LV = VD->getType()->isReferenceType() ?
2388 CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(),
2389 AlignmentSource::Decl) :
2390 CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2391 setObjCGCLValueClass(CGF.getContext(), E, LV);
2395 static llvm::Constant *EmitFunctionDeclPointer(CodeGenModule &CGM,
2396 const FunctionDecl *FD) {
2397 if (FD->hasAttr<WeakRefAttr>()) {
2398 ConstantAddress aliasee = CGM.GetWeakRefReference(FD);
2399 return aliasee.getPointer();
2402 llvm::Constant *V = CGM.GetAddrOfFunction(FD);
2403 if (!FD->hasPrototype()) {
2404 if (const FunctionProtoType *Proto =
2405 FD->getType()->getAs<FunctionProtoType>()) {
2406 // Ugly case: for a K&R-style definition, the type of the definition
2407 // isn't the same as the type of a use. Correct for this with a
2409 QualType NoProtoType =
2410 CGM.getContext().getFunctionNoProtoType(Proto->getReturnType());
2411 NoProtoType = CGM.getContext().getPointerType(NoProtoType);
2412 V = llvm::ConstantExpr::getBitCast(V,
2413 CGM.getTypes().ConvertType(NoProtoType));
2419 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
2420 const Expr *E, const FunctionDecl *FD) {
2421 llvm::Value *V = EmitFunctionDeclPointer(CGF.CGM, FD);
2422 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
2423 return CGF.MakeAddrLValue(V, E->getType(), Alignment,
2424 AlignmentSource::Decl);
2427 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
2428 llvm::Value *ThisValue) {
2429 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
2430 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
2431 return CGF.EmitLValueForField(LV, FD);
2434 /// Named Registers are named metadata pointing to the register name
2435 /// which will be read from/written to as an argument to the intrinsic
2436 /// @llvm.read/write_register.
2437 /// So far, only the name is being passed down, but other options such as
2438 /// register type, allocation type or even optimization options could be
2439 /// passed down via the metadata node.
2440 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) {
2441 SmallString<64> Name("llvm.named.register.");
2442 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
2443 assert(Asm->getLabel().size() < 64-Name.size() &&
2444 "Register name too big");
2445 Name.append(Asm->getLabel());
2446 llvm::NamedMDNode *M =
2447 CGM.getModule().getOrInsertNamedMetadata(Name);
2448 if (M->getNumOperands() == 0) {
2449 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
2451 llvm::Metadata *Ops[] = {Str};
2452 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
2455 CharUnits Alignment = CGM.getContext().getDeclAlign(VD);
2458 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0));
2459 return LValue::MakeGlobalReg(Address(Ptr, Alignment), VD->getType());
2462 /// Determine whether we can emit a reference to \p VD from the current
2463 /// context, despite not necessarily having seen an odr-use of the variable in
2465 static bool canEmitSpuriousReferenceToVariable(CodeGenFunction &CGF,
2466 const DeclRefExpr *E,
2469 // For a variable declared in an enclosing scope, do not emit a spurious
2470 // reference even if we have a capture, as that will emit an unwarranted
2471 // reference to our capture state, and will likely generate worse code than
2472 // emitting a local copy.
2473 if (E->refersToEnclosingVariableOrCapture())
2476 // For a local declaration declared in this function, we can always reference
2477 // it even if we don't have an odr-use.
2478 if (VD->hasLocalStorage()) {
2479 return VD->getDeclContext() ==
2480 dyn_cast_or_null<DeclContext>(CGF.CurCodeDecl);
2483 // For a global declaration, we can emit a reference to it if we know
2484 // for sure that we are able to emit a definition of it.
2485 VD = VD->getDefinition(CGF.getContext());
2489 // Don't emit a spurious reference if it might be to a variable that only
2490 // exists on a different device / target.
2491 // FIXME: This is unnecessarily broad. Check whether this would actually be a
2492 // cross-target reference.
2493 if (CGF.getLangOpts().OpenMP || CGF.getLangOpts().CUDA ||
2494 CGF.getLangOpts().OpenCL) {
2498 // We can emit a spurious reference only if the linkage implies that we'll
2499 // be emitting a non-interposable symbol that will be retained until link
2501 switch (CGF.CGM.getLLVMLinkageVarDefinition(VD, IsConstant)) {
2502 case llvm::GlobalValue::ExternalLinkage:
2503 case llvm::GlobalValue::LinkOnceODRLinkage:
2504 case llvm::GlobalValue::WeakODRLinkage:
2505 case llvm::GlobalValue::InternalLinkage:
2506 case llvm::GlobalValue::PrivateLinkage:
2513 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
2514 const NamedDecl *ND = E->getDecl();
2515 QualType T = E->getType();
2517 assert(E->isNonOdrUse() != NOUR_Unevaluated &&
2518 "should not emit an unevaluated operand");
2520 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2521 // Global Named registers access via intrinsics only
2522 if (VD->getStorageClass() == SC_Register &&
2523 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
2524 return EmitGlobalNamedRegister(VD, CGM);
2526 // If this DeclRefExpr does not constitute an odr-use of the variable,
2527 // we're not permitted to emit a reference to it in general, and it might
2528 // not be captured if capture would be necessary for a use. Emit the
2529 // constant value directly instead.
2530 if (E->isNonOdrUse() == NOUR_Constant &&
2531 (VD->getType()->isReferenceType() ||
2532 !canEmitSpuriousReferenceToVariable(*this, E, VD, true))) {
2533 VD->getAnyInitializer(VD);
2534 llvm::Constant *Val = ConstantEmitter(*this).emitAbstract(
2535 E->getLocation(), *VD->evaluateValue(), VD->getType());
2536 assert(Val && "failed to emit constant expression");
2538 Address Addr = Address::invalid();
2539 if (!VD->getType()->isReferenceType()) {
2540 // Spill the constant value to a global.
2541 Addr = CGM.createUnnamedGlobalFrom(*VD, Val,
2542 getContext().getDeclAlign(VD));
2544 // Should we be using the alignment of the constant pointer we emitted?
2545 CharUnits Alignment =
2546 getNaturalTypeAlignment(E->getType(),
2547 /* BaseInfo= */ nullptr,
2548 /* TBAAInfo= */ nullptr,
2549 /* forPointeeType= */ true);
2550 Addr = Address(Val, Alignment);
2552 return MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2555 // FIXME: Handle other kinds of non-odr-use DeclRefExprs.
2557 // Check for captured variables.
2558 if (E->refersToEnclosingVariableOrCapture()) {
2559 VD = VD->getCanonicalDecl();
2560 if (auto *FD = LambdaCaptureFields.lookup(VD))
2561 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
2562 else if (CapturedStmtInfo) {
2563 auto I = LocalDeclMap.find(VD);
2564 if (I != LocalDeclMap.end()) {
2565 if (VD->getType()->isReferenceType())
2566 return EmitLoadOfReferenceLValue(I->second, VD->getType(),
2567 AlignmentSource::Decl);
2568 return MakeAddrLValue(I->second, T);
2571 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD),
2572 CapturedStmtInfo->getContextValue());
2573 return MakeAddrLValue(
2574 Address(CapLVal.getPointer(), getContext().getDeclAlign(VD)),
2575 CapLVal.getType(), LValueBaseInfo(AlignmentSource::Decl),
2576 CapLVal.getTBAAInfo());
2579 assert(isa<BlockDecl>(CurCodeDecl));
2580 Address addr = GetAddrOfBlockDecl(VD);
2581 return MakeAddrLValue(addr, T, AlignmentSource::Decl);
2585 // FIXME: We should be able to assert this for FunctionDecls as well!
2586 // FIXME: We should be able to assert this for all DeclRefExprs, not just
2587 // those with a valid source location.
2588 assert((ND->isUsed(false) || !isa<VarDecl>(ND) || E->isNonOdrUse() ||
2589 !E->getLocation().isValid()) &&
2590 "Should not use decl without marking it used!");
2592 if (ND->hasAttr<WeakRefAttr>()) {
2593 const auto *VD = cast<ValueDecl>(ND);
2594 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD);
2595 return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl);
2598 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2599 // Check if this is a global variable.
2600 if (VD->hasLinkage() || VD->isStaticDataMember())
2601 return EmitGlobalVarDeclLValue(*this, E, VD);
2603 Address addr = Address::invalid();
2605 // The variable should generally be present in the local decl map.
2606 auto iter = LocalDeclMap.find(VD);
2607 if (iter != LocalDeclMap.end()) {
2608 addr = iter->second;
2610 // Otherwise, it might be static local we haven't emitted yet for
2611 // some reason; most likely, because it's in an outer function.
2612 } else if (VD->isStaticLocal()) {
2613 addr = Address(CGM.getOrCreateStaticVarDecl(
2614 *VD, CGM.getLLVMLinkageVarDefinition(VD, /*IsConstant=*/false)),
2615 getContext().getDeclAlign(VD));
2617 // No other cases for now.
2619 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?");
2623 // Check for OpenMP threadprivate variables.
2624 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd &&
2625 VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2626 return EmitThreadPrivateVarDeclLValue(
2627 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
2631 // Drill into block byref variables.
2632 bool isBlockByref = VD->isEscapingByref();
2634 addr = emitBlockByrefAddress(addr, VD);
2637 // Drill into reference types.
2638 LValue LV = VD->getType()->isReferenceType() ?
2639 EmitLoadOfReferenceLValue(addr, VD->getType(), AlignmentSource::Decl) :
2640 MakeAddrLValue(addr, T, AlignmentSource::Decl);
2642 bool isLocalStorage = VD->hasLocalStorage();
2644 bool NonGCable = isLocalStorage &&
2645 !VD->getType()->isReferenceType() &&
2648 LV.getQuals().removeObjCGCAttr();
2652 bool isImpreciseLifetime =
2653 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
2654 if (isImpreciseLifetime)
2655 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
2656 setObjCGCLValueClass(getContext(), E, LV);
2660 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
2661 return EmitFunctionDeclLValue(*this, E, FD);
2663 // FIXME: While we're emitting a binding from an enclosing scope, all other
2664 // DeclRefExprs we see should be implicitly treated as if they also refer to
2665 // an enclosing scope.
2666 if (const auto *BD = dyn_cast<BindingDecl>(ND))
2667 return EmitLValue(BD->getBinding());
2669 llvm_unreachable("Unhandled DeclRefExpr");
2672 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
2673 // __extension__ doesn't affect lvalue-ness.
2674 if (E->getOpcode() == UO_Extension)
2675 return EmitLValue(E->getSubExpr());
2677 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
2678 switch (E->getOpcode()) {
2679 default: llvm_unreachable("Unknown unary operator lvalue!");
2681 QualType T = E->getSubExpr()->getType()->getPointeeType();
2682 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
2684 LValueBaseInfo BaseInfo;
2685 TBAAAccessInfo TBAAInfo;
2686 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo,
2688 LValue LV = MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo);
2689 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
2691 // We should not generate __weak write barrier on indirect reference
2692 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
2693 // But, we continue to generate __strong write barrier on indirect write
2694 // into a pointer to object.
2695 if (getLangOpts().ObjC &&
2696 getLangOpts().getGC() != LangOptions::NonGC &&
2698 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2703 LValue LV = EmitLValue(E->getSubExpr());
2704 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
2706 // __real is valid on scalars. This is a faster way of testing that.
2707 // __imag can only produce an rvalue on scalars.
2708 if (E->getOpcode() == UO_Real &&
2709 !LV.getAddress().getElementType()->isStructTy()) {
2710 assert(E->getSubExpr()->getType()->isArithmeticType());
2714 QualType T = ExprTy->castAs<ComplexType>()->getElementType();
2717 (E->getOpcode() == UO_Real
2718 ? emitAddrOfRealComponent(LV.getAddress(), LV.getType())
2719 : emitAddrOfImagComponent(LV.getAddress(), LV.getType()));
2720 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo(),
2721 CGM.getTBAAInfoForSubobject(LV, T));
2722 ElemLV.getQuals().addQualifiers(LV.getQuals());
2727 LValue LV = EmitLValue(E->getSubExpr());
2728 bool isInc = E->getOpcode() == UO_PreInc;
2730 if (E->getType()->isAnyComplexType())
2731 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
2733 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
2739 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
2740 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
2741 E->getType(), AlignmentSource::Decl);
2744 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
2745 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
2746 E->getType(), AlignmentSource::Decl);
2749 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
2750 auto SL = E->getFunctionName();
2751 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr");
2752 StringRef FnName = CurFn->getName();
2753 if (FnName.startswith("\01"))
2754 FnName = FnName.substr(1);
2755 StringRef NameItems[] = {
2756 PredefinedExpr::getIdentKindName(E->getIdentKind()), FnName};
2757 std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
2758 if (auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl)) {
2759 std::string Name = SL->getString();
2760 if (!Name.empty()) {
2761 unsigned Discriminator =
2762 CGM.getCXXABI().getMangleContext().getBlockId(BD, true);
2764 Name += "_" + Twine(Discriminator + 1).str();
2765 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str());
2766 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2768 auto C = CGM.GetAddrOfConstantCString(FnName, GVName.c_str());
2769 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2772 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
2773 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2776 /// Emit a type description suitable for use by a runtime sanitizer library. The
2777 /// format of a type descriptor is
2780 /// { i16 TypeKind, i16 TypeInfo }
2783 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2784 /// integer, 1 for a floating point value, and -1 for anything else.
2785 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2786 // Only emit each type's descriptor once.
2787 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
2790 uint16_t TypeKind = -1;
2791 uint16_t TypeInfo = 0;
2793 if (T->isIntegerType()) {
2795 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2796 (T->isSignedIntegerType() ? 1 : 0);
2797 } else if (T->isFloatingType()) {
2799 TypeInfo = getContext().getTypeSize(T);
2802 // Format the type name as if for a diagnostic, including quotes and
2803 // optionally an 'aka'.
2804 SmallString<32> Buffer;
2805 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2806 (intptr_t)T.getAsOpaquePtr(),
2807 StringRef(), StringRef(), None, Buffer,
2810 llvm::Constant *Components[] = {
2811 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2812 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2814 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2816 auto *GV = new llvm::GlobalVariable(
2817 CGM.getModule(), Descriptor->getType(),
2818 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
2819 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2820 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV);
2822 // Remember the descriptor for this type.
2823 CGM.setTypeDescriptorInMap(T, GV);
2828 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2829 llvm::Type *TargetTy = IntPtrTy;
2831 if (V->getType() == TargetTy)
2834 // Floating-point types which fit into intptr_t are bitcast to integers
2835 // and then passed directly (after zero-extension, if necessary).
2836 if (V->getType()->isFloatingPointTy()) {
2837 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2838 if (Bits <= TargetTy->getIntegerBitWidth())
2839 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2843 // Integers which fit in intptr_t are zero-extended and passed directly.
2844 if (V->getType()->isIntegerTy() &&
2845 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2846 return Builder.CreateZExt(V, TargetTy);
2848 // Pointers are passed directly, everything else is passed by address.
2849 if (!V->getType()->isPointerTy()) {
2850 Address Ptr = CreateDefaultAlignTempAlloca(V->getType());
2851 Builder.CreateStore(V, Ptr);
2852 V = Ptr.getPointer();
2854 return Builder.CreatePtrToInt(V, TargetTy);
2857 /// Emit a representation of a SourceLocation for passing to a handler
2858 /// in a sanitizer runtime library. The format for this data is:
2860 /// struct SourceLocation {
2861 /// const char *Filename;
2862 /// int32_t Line, Column;
2865 /// For an invalid SourceLocation, the Filename pointer is null.
2866 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
2867 llvm::Constant *Filename;
2870 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
2871 if (PLoc.isValid()) {
2872 StringRef FilenameString = PLoc.getFilename();
2874 int PathComponentsToStrip =
2875 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip;
2876 if (PathComponentsToStrip < 0) {
2877 assert(PathComponentsToStrip != INT_MIN);
2878 int PathComponentsToKeep = -PathComponentsToStrip;
2879 auto I = llvm::sys::path::rbegin(FilenameString);
2880 auto E = llvm::sys::path::rend(FilenameString);
2881 while (I != E && --PathComponentsToKeep)
2884 FilenameString = FilenameString.substr(I - E);
2885 } else if (PathComponentsToStrip > 0) {
2886 auto I = llvm::sys::path::begin(FilenameString);
2887 auto E = llvm::sys::path::end(FilenameString);
2888 while (I != E && PathComponentsToStrip--)
2893 FilenameString.substr(I - llvm::sys::path::begin(FilenameString));
2895 FilenameString = llvm::sys::path::filename(FilenameString);
2898 auto FilenameGV = CGM.GetAddrOfConstantCString(FilenameString, ".src");
2899 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
2900 cast<llvm::GlobalVariable>(FilenameGV.getPointer()));
2901 Filename = FilenameGV.getPointer();
2902 Line = PLoc.getLine();
2903 Column = PLoc.getColumn();
2905 Filename = llvm::Constant::getNullValue(Int8PtrTy);
2909 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
2910 Builder.getInt32(Column)};
2912 return llvm::ConstantStruct::getAnon(Data);
2916 /// Specify under what conditions this check can be recovered
2917 enum class CheckRecoverableKind {
2918 /// Always terminate program execution if this check fails.
2920 /// Check supports recovering, runtime has both fatal (noreturn) and
2921 /// non-fatal handlers for this check.
2923 /// Runtime conditionally aborts, always need to support recovery.
2928 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) {
2929 assert(Kind.countPopulation() == 1);
2930 if (Kind == SanitizerKind::Function || Kind == SanitizerKind::Vptr)
2931 return CheckRecoverableKind::AlwaysRecoverable;
2932 else if (Kind == SanitizerKind::Return || Kind == SanitizerKind::Unreachable)
2933 return CheckRecoverableKind::Unrecoverable;
2935 return CheckRecoverableKind::Recoverable;
2939 struct SanitizerHandlerInfo {
2940 char const *const Name;
2945 const SanitizerHandlerInfo SanitizerHandlers[] = {
2946 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version},
2947 LIST_SANITIZER_CHECKS
2948 #undef SANITIZER_CHECK
2951 static void emitCheckHandlerCall(CodeGenFunction &CGF,
2952 llvm::FunctionType *FnType,
2953 ArrayRef<llvm::Value *> FnArgs,
2954 SanitizerHandler CheckHandler,
2955 CheckRecoverableKind RecoverKind, bool IsFatal,
2956 llvm::BasicBlock *ContBB) {
2957 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable);
2958 Optional<ApplyDebugLocation> DL;
2959 if (!CGF.Builder.getCurrentDebugLocation()) {
2960 // Ensure that the call has at least an artificial debug location.
2961 DL.emplace(CGF, SourceLocation());
2963 bool NeedsAbortSuffix =
2964 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable;
2965 bool MinimalRuntime = CGF.CGM.getCodeGenOpts().SanitizeMinimalRuntime;
2966 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler];
2967 const StringRef CheckName = CheckInfo.Name;
2968 std::string FnName = "__ubsan_handle_" + CheckName.str();
2969 if (CheckInfo.Version && !MinimalRuntime)
2970 FnName += "_v" + llvm::utostr(CheckInfo.Version);
2972 FnName += "_minimal";
2973 if (NeedsAbortSuffix)
2976 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable;
2978 llvm::AttrBuilder B;
2980 B.addAttribute(llvm::Attribute::NoReturn)
2981 .addAttribute(llvm::Attribute::NoUnwind);
2983 B.addAttribute(llvm::Attribute::UWTable);
2985 llvm::FunctionCallee Fn = CGF.CGM.CreateRuntimeFunction(
2987 llvm::AttributeList::get(CGF.getLLVMContext(),
2988 llvm::AttributeList::FunctionIndex, B),
2990 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs);
2992 HandlerCall->setDoesNotReturn();
2993 CGF.Builder.CreateUnreachable();
2995 CGF.Builder.CreateBr(ContBB);
2999 void CodeGenFunction::EmitCheck(
3000 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
3001 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs,
3002 ArrayRef<llvm::Value *> DynamicArgs) {
3003 assert(IsSanitizerScope);
3004 assert(Checked.size() > 0);
3005 assert(CheckHandler >= 0 &&
3006 size_t(CheckHandler) < llvm::array_lengthof(SanitizerHandlers));
3007 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name;
3009 llvm::Value *FatalCond = nullptr;
3010 llvm::Value *RecoverableCond = nullptr;
3011 llvm::Value *TrapCond = nullptr;
3012 for (int i = 0, n = Checked.size(); i < n; ++i) {
3013 llvm::Value *Check = Checked[i].first;
3014 // -fsanitize-trap= overrides -fsanitize-recover=.
3015 llvm::Value *&Cond =
3016 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second)
3018 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second)
3021 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check;
3025 EmitTrapCheck(TrapCond);
3026 if (!FatalCond && !RecoverableCond)
3029 llvm::Value *JointCond;
3030 if (FatalCond && RecoverableCond)
3031 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond);
3033 JointCond = FatalCond ? FatalCond : RecoverableCond;
3036 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second);
3037 assert(SanOpts.has(Checked[0].second));
3039 for (int i = 1, n = Checked.size(); i < n; ++i) {
3040 assert(RecoverKind == getRecoverableKind(Checked[i].second) &&
3041 "All recoverable kinds in a single check must be same!");
3042 assert(SanOpts.has(Checked[i].second));
3046 llvm::BasicBlock *Cont = createBasicBlock("cont");
3047 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName);
3048 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers);
3049 // Give hint that we very much don't expect to execute the handler
3050 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
3051 llvm::MDBuilder MDHelper(getLLVMContext());
3052 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
3053 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
3054 EmitBlock(Handlers);
3056 // Handler functions take an i8* pointing to the (handler-specific) static
3057 // information block, followed by a sequence of intptr_t arguments
3058 // representing operand values.
3059 SmallVector<llvm::Value *, 4> Args;
3060 SmallVector<llvm::Type *, 4> ArgTypes;
3061 if (!CGM.getCodeGenOpts().SanitizeMinimalRuntime) {
3062 Args.reserve(DynamicArgs.size() + 1);
3063 ArgTypes.reserve(DynamicArgs.size() + 1);
3065 // Emit handler arguments and create handler function type.
3066 if (!StaticArgs.empty()) {
3067 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3069 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
3070 llvm::GlobalVariable::PrivateLinkage, Info);
3071 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3072 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3073 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
3074 ArgTypes.push_back(Int8PtrTy);
3077 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
3078 Args.push_back(EmitCheckValue(DynamicArgs[i]));
3079 ArgTypes.push_back(IntPtrTy);
3083 llvm::FunctionType *FnType =
3084 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
3086 if (!FatalCond || !RecoverableCond) {
3087 // Simple case: we need to generate a single handler call, either
3088 // fatal, or non-fatal.
3089 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind,
3090 (FatalCond != nullptr), Cont);
3092 // Emit two handler calls: first one for set of unrecoverable checks,
3093 // another one for recoverable.
3094 llvm::BasicBlock *NonFatalHandlerBB =
3095 createBasicBlock("non_fatal." + CheckName);
3096 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName);
3097 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB);
3098 EmitBlock(FatalHandlerBB);
3099 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true,
3101 EmitBlock(NonFatalHandlerBB);
3102 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false,
3109 void CodeGenFunction::EmitCfiSlowPathCheck(
3110 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId,
3111 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) {
3112 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont");
3114 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath");
3115 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB);
3117 llvm::MDBuilder MDHelper(getLLVMContext());
3118 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
3119 BI->setMetadata(llvm::LLVMContext::MD_prof, Node);
3123 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind);
3125 llvm::CallInst *CheckCall;
3126 llvm::FunctionCallee SlowPathFn;
3128 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3130 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
3131 llvm::GlobalVariable::PrivateLinkage, Info);
3132 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3133 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3135 SlowPathFn = CGM.getModule().getOrInsertFunction(
3136 "__cfi_slowpath_diag",
3137 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy},
3139 CheckCall = Builder.CreateCall(
3140 SlowPathFn, {TypeId, Ptr, Builder.CreateBitCast(InfoPtr, Int8PtrTy)});
3142 SlowPathFn = CGM.getModule().getOrInsertFunction(
3144 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false));
3145 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr});
3149 cast<llvm::GlobalValue>(SlowPathFn.getCallee()->stripPointerCasts()));
3150 CheckCall->setDoesNotThrow();
3155 // Emit a stub for __cfi_check function so that the linker knows about this
3156 // symbol in LTO mode.
3157 void CodeGenFunction::EmitCfiCheckStub() {
3158 llvm::Module *M = &CGM.getModule();
3159 auto &Ctx = M->getContext();
3160 llvm::Function *F = llvm::Function::Create(
3161 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false),
3162 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M);
3164 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F);
3165 // FIXME: consider emitting an intrinsic call like
3166 // call void @llvm.cfi_check(i64 %0, i8* %1, i8* %2)
3167 // which can be lowered in CrossDSOCFI pass to the actual contents of
3168 // __cfi_check. This would allow inlining of __cfi_check calls.
3169 llvm::CallInst::Create(
3170 llvm::Intrinsic::getDeclaration(M, llvm::Intrinsic::trap), "", BB);
3171 llvm::ReturnInst::Create(Ctx, nullptr, BB);
3174 // This function is basically a switch over the CFI failure kind, which is
3175 // extracted from CFICheckFailData (1st function argument). Each case is either
3176 // llvm.trap or a call to one of the two runtime handlers, based on
3177 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid
3178 // failure kind) traps, but this should really never happen. CFICheckFailData
3179 // can be nullptr if the calling module has -fsanitize-trap behavior for this
3180 // check kind; in this case __cfi_check_fail traps as well.
3181 void CodeGenFunction::EmitCfiCheckFail() {
3182 SanitizerScope SanScope(this);
3183 FunctionArgList Args;
3184 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy,
3185 ImplicitParamDecl::Other);
3186 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy,
3187 ImplicitParamDecl::Other);
3188 Args.push_back(&ArgData);
3189 Args.push_back(&ArgAddr);
3191 const CGFunctionInfo &FI =
3192 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args);
3194 llvm::Function *F = llvm::Function::Create(
3195 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false),
3196 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule());
3197 F->setVisibility(llvm::GlobalValue::HiddenVisibility);
3199 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args,
3202 // This function should not be affected by blacklist. This function does
3203 // not have a source location, but "src:*" would still apply. Revert any
3204 // changes to SanOpts made in StartFunction.
3205 SanOpts = CGM.getLangOpts().Sanitize;
3208 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false,
3209 CGM.getContext().VoidPtrTy, ArgData.getLocation());
3211 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false,
3212 CGM.getContext().VoidPtrTy, ArgAddr.getLocation());
3214 // Data == nullptr means the calling module has trap behaviour for this check.
3215 llvm::Value *DataIsNotNullPtr =
3216 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy));
3217 EmitTrapCheck(DataIsNotNullPtr);
3219 llvm::StructType *SourceLocationTy =
3220 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty);
3221 llvm::StructType *CfiCheckFailDataTy =
3222 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy);
3224 llvm::Value *V = Builder.CreateConstGEP2_32(
3226 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0,
3228 Address CheckKindAddr(V, getIntAlign());
3229 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr);
3231 llvm::Value *AllVtables = llvm::MetadataAsValue::get(
3232 CGM.getLLVMContext(),
3233 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
3234 llvm::Value *ValidVtable = Builder.CreateZExt(
3235 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test),
3236 {Addr, AllVtables}),
3239 const std::pair<int, SanitizerMask> CheckKinds[] = {
3240 {CFITCK_VCall, SanitizerKind::CFIVCall},
3241 {CFITCK_NVCall, SanitizerKind::CFINVCall},
3242 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast},
3243 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast},
3244 {CFITCK_ICall, SanitizerKind::CFIICall}};
3246 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks;
3247 for (auto CheckKindMaskPair : CheckKinds) {
3248 int Kind = CheckKindMaskPair.first;
3249 SanitizerMask Mask = CheckKindMaskPair.second;
3251 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind));
3252 if (CGM.getLangOpts().Sanitize.has(Mask))
3253 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {},
3254 {Data, Addr, ValidVtable});
3256 EmitTrapCheck(Cond);
3260 // The only reference to this function will be created during LTO link.
3261 // Make sure it survives until then.
3262 CGM.addUsedGlobal(F);
3265 void CodeGenFunction::EmitUnreachable(SourceLocation Loc) {
3266 if (SanOpts.has(SanitizerKind::Unreachable)) {
3267 SanitizerScope SanScope(this);
3268 EmitCheck(std::make_pair(static_cast<llvm::Value *>(Builder.getFalse()),
3269 SanitizerKind::Unreachable),
3270 SanitizerHandler::BuiltinUnreachable,
3271 EmitCheckSourceLocation(Loc), None);
3273 Builder.CreateUnreachable();
3276 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
3277 llvm::BasicBlock *Cont = createBasicBlock("cont");
3279 // If we're optimizing, collapse all calls to trap down to just one per
3280 // function to save on code size.
3281 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
3282 TrapBB = createBasicBlock("trap");
3283 Builder.CreateCondBr(Checked, Cont, TrapBB);
3285 llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
3286 TrapCall->setDoesNotReturn();
3287 TrapCall->setDoesNotThrow();
3288 Builder.CreateUnreachable();
3290 Builder.CreateCondBr(Checked, Cont, TrapBB);
3296 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) {
3297 llvm::CallInst *TrapCall = Builder.CreateCall(CGM.getIntrinsic(IntrID));
3299 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
3300 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",
3301 CGM.getCodeGenOpts().TrapFuncName);
3302 TrapCall->addAttribute(llvm::AttributeList::FunctionIndex, A);
3308 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E,
3309 LValueBaseInfo *BaseInfo,
3310 TBAAAccessInfo *TBAAInfo) {
3311 assert(E->getType()->isArrayType() &&
3312 "Array to pointer decay must have array source type!");
3314 // Expressions of array type can't be bitfields or vector elements.
3315 LValue LV = EmitLValue(E);
3316 Address Addr = LV.getAddress();
3318 // If the array type was an incomplete type, we need to make sure
3319 // the decay ends up being the right type.
3320 llvm::Type *NewTy = ConvertType(E->getType());
3321 Addr = Builder.CreateElementBitCast(Addr, NewTy);
3323 // Note that VLA pointers are always decayed, so we don't need to do
3325 if (!E->getType()->isVariableArrayType()) {
3326 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3327 "Expected pointer to array");
3328 Addr = Builder.CreateConstArrayGEP(Addr, 0, "arraydecay");
3331 // The result of this decay conversion points to an array element within the
3332 // base lvalue. However, since TBAA currently does not support representing
3333 // accesses to elements of member arrays, we conservatively represent accesses
3334 // to the pointee object as if it had no any base lvalue specified.
3335 // TODO: Support TBAA for member arrays.
3336 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType();
3337 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
3338 if (TBAAInfo) *TBAAInfo = CGM.getTBAAAccessInfo(EltType);
3340 return Builder.CreateElementBitCast(Addr, ConvertTypeForMem(EltType));
3343 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
3344 /// array to pointer, return the array subexpression.
3345 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
3346 // If this isn't just an array->pointer decay, bail out.
3347 const auto *CE = dyn_cast<CastExpr>(E);
3348 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
3351 // If this is a decay from variable width array, bail out.
3352 const Expr *SubExpr = CE->getSubExpr();
3353 if (SubExpr->getType()->isVariableArrayType())
3359 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
3361 ArrayRef<llvm::Value*> indices,
3365 const llvm::Twine &name = "arrayidx") {
3367 return CGF.EmitCheckedInBoundsGEP(ptr, indices, signedIndices,
3368 CodeGenFunction::NotSubtraction, loc,
3371 return CGF.Builder.CreateGEP(ptr, indices, name);
3375 static CharUnits getArrayElementAlign(CharUnits arrayAlign,
3377 CharUnits eltSize) {
3378 // If we have a constant index, we can use the exact offset of the
3379 // element we're accessing.
3380 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) {
3381 CharUnits offset = constantIdx->getZExtValue() * eltSize;
3382 return arrayAlign.alignmentAtOffset(offset);
3384 // Otherwise, use the worst-case alignment for any element.
3386 return arrayAlign.alignmentOfArrayElement(eltSize);
3390 static QualType getFixedSizeElementType(const ASTContext &ctx,
3391 const VariableArrayType *vla) {
3394 eltType = vla->getElementType();
3395 } while ((vla = ctx.getAsVariableArrayType(eltType)));
3399 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
3400 ArrayRef<llvm::Value *> indices,
3401 QualType eltType, bool inbounds,
3402 bool signedIndices, SourceLocation loc,
3403 const llvm::Twine &name = "arrayidx") {
3404 // All the indices except that last must be zero.
3406 for (auto idx : indices.drop_back())
3407 assert(isa<llvm::ConstantInt>(idx) &&
3408 cast<llvm::ConstantInt>(idx)->isZero());
3411 // Determine the element size of the statically-sized base. This is
3412 // the thing that the indices are expressed in terms of.
3413 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) {
3414 eltType = getFixedSizeElementType(CGF.getContext(), vla);
3417 // We can use that to compute the best alignment of the element.
3418 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
3419 CharUnits eltAlign =
3420 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
3422 llvm::Value *eltPtr;
3423 auto LastIndex = dyn_cast<llvm::ConstantInt>(indices.back());
3424 if (!CGF.IsInPreservedAIRegion || !LastIndex) {
3425 eltPtr = emitArraySubscriptGEP(
3426 CGF, addr.getPointer(), indices, inbounds, signedIndices,
3429 // Remember the original array subscript for bpf target
3430 unsigned idx = LastIndex->getZExtValue();
3431 eltPtr = CGF.Builder.CreatePreserveArrayAccessIndex(addr.getPointer(),
3436 return Address(eltPtr, eltAlign);
3439 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3441 // The index must always be an integer, which is not an aggregate. Emit it
3442 // in lexical order (this complexity is, sadly, required by C++17).
3443 llvm::Value *IdxPre =
3444 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr;
3445 bool SignedIndices = false;
3446 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * {
3448 if (E->getLHS() != E->getIdx()) {
3449 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS");
3450 Idx = EmitScalarExpr(E->getIdx());
3453 QualType IdxTy = E->getIdx()->getType();
3454 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
3455 SignedIndices |= IdxSigned;
3457 if (SanOpts.has(SanitizerKind::ArrayBounds))
3458 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
3460 // Extend or truncate the index type to 32 or 64-bits.
3461 if (Promote && Idx->getType() != IntPtrTy)
3462 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
3468 // If the base is a vector type, then we are forming a vector element lvalue
3469 // with this subscript.
3470 if (E->getBase()->getType()->isVectorType() &&
3471 !isa<ExtVectorElementExpr>(E->getBase())) {
3472 // Emit the vector as an lvalue to get its address.
3473 LValue LHS = EmitLValue(E->getBase());
3474 auto *Idx = EmitIdxAfterBase(/*Promote*/false);
3475 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
3476 return LValue::MakeVectorElt(LHS.getAddress(), Idx, E->getBase()->getType(),
3477 LHS.getBaseInfo(), TBAAAccessInfo());
3480 // All the other cases basically behave like simple offsetting.
3482 // Handle the extvector case we ignored above.
3483 if (isa<ExtVectorElementExpr>(E->getBase())) {
3484 LValue LV = EmitLValue(E->getBase());
3485 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3486 Address Addr = EmitExtVectorElementLValue(LV);
3488 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
3489 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true,
3490 SignedIndices, E->getExprLoc());
3491 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo(),
3492 CGM.getTBAAInfoForSubobject(LV, EltType));
3495 LValueBaseInfo EltBaseInfo;
3496 TBAAAccessInfo EltTBAAInfo;
3497 Address Addr = Address::invalid();
3498 if (const VariableArrayType *vla =
3499 getContext().getAsVariableArrayType(E->getType())) {
3500 // The base must be a pointer, which is not an aggregate. Emit
3501 // it. It needs to be emitted first in case it's what captures
3503 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3504 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3506 // The element count here is the total number of non-VLA elements.
3507 llvm::Value *numElements = getVLASize(vla).NumElts;
3509 // Effectively, the multiply by the VLA size is part of the GEP.
3510 // GEP indexes are signed, and scaling an index isn't permitted to
3511 // signed-overflow, so we use the same semantics for our explicit
3512 // multiply. We suppress this if overflow is not undefined behavior.
3513 if (getLangOpts().isSignedOverflowDefined()) {
3514 Idx = Builder.CreateMul(Idx, numElements);
3516 Idx = Builder.CreateNSWMul(Idx, numElements);
3519 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
3520 !getLangOpts().isSignedOverflowDefined(),
3521 SignedIndices, E->getExprLoc());
3523 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
3524 // Indexing over an interface, as in "NSString *P; P[4];"
3526 // Emit the base pointer.
3527 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3528 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3530 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT);
3531 llvm::Value *InterfaceSizeVal =
3532 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity());
3534 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal);
3536 // We don't necessarily build correct LLVM struct types for ObjC
3537 // interfaces, so we can't rely on GEP to do this scaling
3538 // correctly, so we need to cast to i8*. FIXME: is this actually
3539 // true? A lot of other things in the fragile ABI would break...
3540 llvm::Type *OrigBaseTy = Addr.getType();
3541 Addr = Builder.CreateElementBitCast(Addr, Int8Ty);
3544 CharUnits EltAlign =
3545 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
3546 llvm::Value *EltPtr =
3547 emitArraySubscriptGEP(*this, Addr.getPointer(), ScaledIdx, false,
3548 SignedIndices, E->getExprLoc());
3549 Addr = Address(EltPtr, EltAlign);
3552 Addr = Builder.CreateBitCast(Addr, OrigBaseTy);
3553 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3554 // If this is A[i] where A is an array, the frontend will have decayed the
3555 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3556 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3557 // "gep x, i" here. Emit one "gep A, 0, i".
3558 assert(Array->getType()->isArrayType() &&
3559 "Array to pointer decay must have array source type!");
3561 // For simple multidimensional array indexing, set the 'accessed' flag for
3562 // better bounds-checking of the base expression.
3563 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3564 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3566 ArrayLV = EmitLValue(Array);
3567 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3569 // Propagate the alignment from the array itself to the result.
3570 Addr = emitArraySubscriptGEP(
3571 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3572 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices,
3574 EltBaseInfo = ArrayLV.getBaseInfo();
3575 EltTBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, E->getType());
3577 // The base must be a pointer; emit it with an estimate of its alignment.
3578 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3579 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3580 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
3581 !getLangOpts().isSignedOverflowDefined(),
3582 SignedIndices, E->getExprLoc());
3585 LValue LV = MakeAddrLValue(Addr, E->getType(), EltBaseInfo, EltTBAAInfo);
3587 if (getLangOpts().ObjC &&
3588 getLangOpts().getGC() != LangOptions::NonGC) {
3589 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
3590 setObjCGCLValueClass(getContext(), E, LV);
3595 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base,
3596 LValueBaseInfo &BaseInfo,
3597 TBAAAccessInfo &TBAAInfo,
3598 QualType BaseTy, QualType ElTy,
3599 bool IsLowerBound) {
3601 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) {
3602 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound);
3603 if (BaseTy->isArrayType()) {
3604 Address Addr = BaseLVal.getAddress();
3605 BaseInfo = BaseLVal.getBaseInfo();
3607 // If the array type was an incomplete type, we need to make sure
3608 // the decay ends up being the right type.
3609 llvm::Type *NewTy = CGF.ConvertType(BaseTy);
3610 Addr = CGF.Builder.CreateElementBitCast(Addr, NewTy);
3612 // Note that VLA pointers are always decayed, so we don't need to do
3614 if (!BaseTy->isVariableArrayType()) {
3615 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3616 "Expected pointer to array");
3617 Addr = CGF.Builder.CreateConstArrayGEP(Addr, 0, "arraydecay");
3620 return CGF.Builder.CreateElementBitCast(Addr,
3621 CGF.ConvertTypeForMem(ElTy));
3623 LValueBaseInfo TypeBaseInfo;
3624 TBAAAccessInfo TypeTBAAInfo;
3625 CharUnits Align = CGF.getNaturalTypeAlignment(ElTy, &TypeBaseInfo,
3627 BaseInfo.mergeForCast(TypeBaseInfo);
3628 TBAAInfo = CGF.CGM.mergeTBAAInfoForCast(TBAAInfo, TypeTBAAInfo);
3629 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress()), Align);
3631 return CGF.EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo);
3634 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3635 bool IsLowerBound) {
3636 QualType BaseTy = OMPArraySectionExpr::getBaseOriginalType(E->getBase());
3637 QualType ResultExprTy;
3638 if (auto *AT = getContext().getAsArrayType(BaseTy))
3639 ResultExprTy = AT->getElementType();
3641 ResultExprTy = BaseTy->getPointeeType();
3642 llvm::Value *Idx = nullptr;
3643 if (IsLowerBound || E->getColonLoc().isInvalid()) {
3644 // Requesting lower bound or upper bound, but without provided length and
3645 // without ':' symbol for the default length -> length = 1.
3646 // Idx = LowerBound ?: 0;
3647 if (auto *LowerBound = E->getLowerBound()) {
3648 Idx = Builder.CreateIntCast(
3649 EmitScalarExpr(LowerBound), IntPtrTy,
3650 LowerBound->getType()->hasSignedIntegerRepresentation());
3652 Idx = llvm::ConstantInt::getNullValue(IntPtrTy);
3654 // Try to emit length or lower bound as constant. If this is possible, 1
3655 // is subtracted from constant length or lower bound. Otherwise, emit LLVM
3656 // IR (LB + Len) - 1.
3657 auto &C = CGM.getContext();
3658 auto *Length = E->getLength();
3659 llvm::APSInt ConstLength;
3661 // Idx = LowerBound + Length - 1;
3662 if (Length->isIntegerConstantExpr(ConstLength, C)) {
3663 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3666 auto *LowerBound = E->getLowerBound();
3667 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false);
3668 if (LowerBound && LowerBound->isIntegerConstantExpr(ConstLowerBound, C)) {
3669 ConstLowerBound = ConstLowerBound.zextOrTrunc(PointerWidthInBits);
3670 LowerBound = nullptr;
3674 else if (!LowerBound)
3677 if (Length || LowerBound) {
3678 auto *LowerBoundVal =
3680 ? Builder.CreateIntCast(
3681 EmitScalarExpr(LowerBound), IntPtrTy,
3682 LowerBound->getType()->hasSignedIntegerRepresentation())
3683 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound);
3686 ? Builder.CreateIntCast(
3687 EmitScalarExpr(Length), IntPtrTy,
3688 Length->getType()->hasSignedIntegerRepresentation())
3689 : llvm::ConstantInt::get(IntPtrTy, ConstLength);
3690 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len",
3692 !getLangOpts().isSignedOverflowDefined());
3693 if (Length && LowerBound) {
3694 Idx = Builder.CreateSub(
3695 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1",
3696 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3699 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound);
3701 // Idx = ArraySize - 1;
3702 QualType ArrayTy = BaseTy->isPointerType()
3703 ? E->getBase()->IgnoreParenImpCasts()->getType()
3705 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) {
3706 Length = VAT->getSizeExpr();
3707 if (Length->isIntegerConstantExpr(ConstLength, C))
3710 auto *CAT = C.getAsConstantArrayType(ArrayTy);
3711 ConstLength = CAT->getSize();
3714 auto *LengthVal = Builder.CreateIntCast(
3715 EmitScalarExpr(Length), IntPtrTy,
3716 Length->getType()->hasSignedIntegerRepresentation());
3717 Idx = Builder.CreateSub(
3718 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1",
3719 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3721 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3723 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength);
3729 Address EltPtr = Address::invalid();
3730 LValueBaseInfo BaseInfo;
3731 TBAAAccessInfo TBAAInfo;
3732 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) {
3733 // The base must be a pointer, which is not an aggregate. Emit
3734 // it. It needs to be emitted first in case it's what captures
3737 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo,
3738 BaseTy, VLA->getElementType(), IsLowerBound);
3739 // The element count here is the total number of non-VLA elements.
3740 llvm::Value *NumElements = getVLASize(VLA).NumElts;
3742 // Effectively, the multiply by the VLA size is part of the GEP.
3743 // GEP indexes are signed, and scaling an index isn't permitted to
3744 // signed-overflow, so we use the same semantics for our explicit
3745 // multiply. We suppress this if overflow is not undefined behavior.
3746 if (getLangOpts().isSignedOverflowDefined())
3747 Idx = Builder.CreateMul(Idx, NumElements);
3749 Idx = Builder.CreateNSWMul(Idx, NumElements);
3750 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
3751 !getLangOpts().isSignedOverflowDefined(),
3752 /*signedIndices=*/false, E->getExprLoc());
3753 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3754 // If this is A[i] where A is an array, the frontend will have decayed the
3755 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3756 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3757 // "gep x, i" here. Emit one "gep A, 0, i".
3758 assert(Array->getType()->isArrayType() &&
3759 "Array to pointer decay must have array source type!");
3761 // For simple multidimensional array indexing, set the 'accessed' flag for
3762 // better bounds-checking of the base expression.
3763 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3764 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3766 ArrayLV = EmitLValue(Array);
3768 // Propagate the alignment from the array itself to the result.
3769 EltPtr = emitArraySubscriptGEP(
3770 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3771 ResultExprTy, !getLangOpts().isSignedOverflowDefined(),
3772 /*signedIndices=*/false, E->getExprLoc());
3773 BaseInfo = ArrayLV.getBaseInfo();
3774 TBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, ResultExprTy);
3776 Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo,
3777 TBAAInfo, BaseTy, ResultExprTy,
3779 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
3780 !getLangOpts().isSignedOverflowDefined(),
3781 /*signedIndices=*/false, E->getExprLoc());
3784 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo, TBAAInfo);
3787 LValue CodeGenFunction::
3788 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
3789 // Emit the base vector as an l-value.
3792 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
3794 // If it is a pointer to a vector, emit the address and form an lvalue with
3796 LValueBaseInfo BaseInfo;
3797 TBAAAccessInfo TBAAInfo;
3798 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo, &TBAAInfo);
3799 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
3800 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo, TBAAInfo);
3801 Base.getQuals().removeObjCGCAttr();
3802 } else if (E->getBase()->isGLValue()) {
3803 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
3804 // emit the base as an lvalue.
3805 assert(E->getBase()->getType()->isVectorType());
3806 Base = EmitLValue(E->getBase());
3808 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
3809 assert(E->getBase()->getType()->isVectorType() &&
3810 "Result must be a vector");
3811 llvm::Value *Vec = EmitScalarExpr(E->getBase());
3813 // Store the vector to memory (because LValue wants an address).
3814 Address VecMem = CreateMemTemp(E->getBase()->getType());
3815 Builder.CreateStore(Vec, VecMem);
3816 Base = MakeAddrLValue(VecMem, E->getBase()->getType(),
3817 AlignmentSource::Decl);
3821 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
3823 // Encode the element access list into a vector of unsigned indices.
3824 SmallVector<uint32_t, 4> Indices;
3825 E->getEncodedElementAccess(Indices);
3827 if (Base.isSimple()) {
3828 llvm::Constant *CV =
3829 llvm::ConstantDataVector::get(getLLVMContext(), Indices);
3830 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
3831 Base.getBaseInfo(), TBAAAccessInfo());
3833 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
3835 llvm::Constant *BaseElts = Base.getExtVectorElts();
3836 SmallVector<llvm::Constant *, 4> CElts;
3838 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
3839 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
3840 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
3841 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type,
3842 Base.getBaseInfo(), TBAAAccessInfo());
3845 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
3846 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, E)) {
3847 EmitIgnoredExpr(E->getBase());
3848 return EmitDeclRefLValue(DRE);
3851 Expr *BaseExpr = E->getBase();
3852 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
3855 LValueBaseInfo BaseInfo;
3856 TBAAAccessInfo TBAAInfo;
3857 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo, &TBAAInfo);
3858 QualType PtrTy = BaseExpr->getType()->getPointeeType();
3859 SanitizerSet SkippedChecks;
3860 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr);
3862 SkippedChecks.set(SanitizerKind::Alignment, true);
3863 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr))
3864 SkippedChecks.set(SanitizerKind::Null, true);
3865 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy,
3866 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
3867 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo, TBAAInfo);
3869 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
3871 NamedDecl *ND = E->getMemberDecl();
3872 if (auto *Field = dyn_cast<FieldDecl>(ND)) {
3873 LValue LV = EmitLValueForField(BaseLV, Field);
3874 setObjCGCLValueClass(getContext(), E, LV);
3878 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
3879 return EmitFunctionDeclLValue(*this, E, FD);
3881 llvm_unreachable("Unhandled member declaration!");
3884 /// Given that we are currently emitting a lambda, emit an l-value for
3885 /// one of its members.
3886 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
3887 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
3888 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
3889 QualType LambdaTagType =
3890 getContext().getTagDeclType(Field->getParent());
3891 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
3892 return EmitLValueForField(LambdaLV, Field);
3895 /// Get the field index in the debug info. The debug info structure/union
3896 /// will ignore the unnamed bitfields.
3897 unsigned CodeGenFunction::getDebugInfoFIndex(const RecordDecl *Rec,
3898 unsigned FieldIndex) {
3899 unsigned I = 0, Skipped = 0;
3901 for (auto F : Rec->getDefinition()->fields()) {
3902 if (I == FieldIndex)
3904 if (F->isUnnamedBitfield())
3909 return FieldIndex - Skipped;
3912 /// Get the address of a zero-sized field within a record. The resulting
3913 /// address doesn't necessarily have the right type.
3914 static Address emitAddrOfZeroSizeField(CodeGenFunction &CGF, Address Base,
3915 const FieldDecl *Field) {
3916 CharUnits Offset = CGF.getContext().toCharUnitsFromBits(
3917 CGF.getContext().getFieldOffset(Field));
3918 if (Offset.isZero())
3920 Base = CGF.Builder.CreateElementBitCast(Base, CGF.Int8Ty);
3921 return CGF.Builder.CreateConstInBoundsByteGEP(Base, Offset);
3924 /// Drill down to the storage of a field without walking into
3925 /// reference types.
3927 /// The resulting address doesn't necessarily have the right type.
3928 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
3929 const FieldDecl *field) {
3930 if (field->isZeroSize(CGF.getContext()))
3931 return emitAddrOfZeroSizeField(CGF, base, field);
3933 const RecordDecl *rec = field->getParent();
3936 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
3938 return CGF.Builder.CreateStructGEP(base, idx, field->getName());
3941 static Address emitPreserveStructAccess(CodeGenFunction &CGF, Address base,
3942 const FieldDecl *field) {
3943 const RecordDecl *rec = field->getParent();
3944 llvm::DIType *DbgInfo = CGF.getDebugInfo()->getOrCreateRecordType(
3945 CGF.getContext().getRecordType(rec), rec->getLocation());
3948 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
3950 return CGF.Builder.CreatePreserveStructAccessIndex(
3951 base, idx, CGF.getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo);
3954 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) {
3955 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl();
3959 if (RD->isDynamicClass())
3962 for (const auto &Base : RD->bases())
3963 if (hasAnyVptr(Base.getType(), Context))
3966 for (const FieldDecl *Field : RD->fields())
3967 if (hasAnyVptr(Field->getType(), Context))
3973 LValue CodeGenFunction::EmitLValueForField(LValue base,
3974 const FieldDecl *field) {
3975 LValueBaseInfo BaseInfo = base.getBaseInfo();
3977 if (field->isBitField()) {
3978 const CGRecordLayout &RL =
3979 CGM.getTypes().getCGRecordLayout(field->getParent());
3980 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
3981 Address Addr = base.getAddress();
3982 unsigned Idx = RL.getLLVMFieldNo(field);
3984 // For structs, we GEP to the field that the record layout suggests.
3985 Addr = Builder.CreateStructGEP(Addr, Idx, field->getName());
3986 // Get the access type.
3987 llvm::Type *FieldIntTy =
3988 llvm::Type::getIntNTy(getLLVMContext(), Info.StorageSize);
3989 if (Addr.getElementType() != FieldIntTy)
3990 Addr = Builder.CreateElementBitCast(Addr, FieldIntTy);
3992 QualType fieldType =
3993 field->getType().withCVRQualifiers(base.getVRQualifiers());
3994 // TODO: Support TBAA for bit fields.
3995 LValueBaseInfo FieldBaseInfo(BaseInfo.getAlignmentSource());
3996 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo,
4000 // Fields of may-alias structures are may-alias themselves.
4001 // FIXME: this should get propagated down through anonymous structs
4003 QualType FieldType = field->getType();
4004 const RecordDecl *rec = field->getParent();
4005 AlignmentSource BaseAlignSource = BaseInfo.getAlignmentSource();
4006 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(BaseAlignSource));
4007 TBAAAccessInfo FieldTBAAInfo;
4008 if (base.getTBAAInfo().isMayAlias() ||
4009 rec->hasAttr<MayAliasAttr>() || FieldType->isVectorType()) {
4010 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
4011 } else if (rec->isUnion()) {
4012 // TODO: Support TBAA for unions.
4013 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
4015 // If no base type been assigned for the base access, then try to generate
4016 // one for this base lvalue.
4017 FieldTBAAInfo = base.getTBAAInfo();
4018 if (!FieldTBAAInfo.BaseType) {
4019 FieldTBAAInfo.BaseType = CGM.getTBAABaseTypeInfo(base.getType());
4020 assert(!FieldTBAAInfo.Offset &&
4021 "Nonzero offset for an access with no base type!");
4024 // Adjust offset to be relative to the base type.
4025 const ASTRecordLayout &Layout =
4026 getContext().getASTRecordLayout(field->getParent());
4027 unsigned CharWidth = getContext().getCharWidth();
4028 if (FieldTBAAInfo.BaseType)
4029 FieldTBAAInfo.Offset +=
4030 Layout.getFieldOffset(field->getFieldIndex()) / CharWidth;
4032 // Update the final access type and size.
4033 FieldTBAAInfo.AccessType = CGM.getTBAATypeInfo(FieldType);
4034 FieldTBAAInfo.Size =
4035 getContext().getTypeSizeInChars(FieldType).getQuantity();
4038 Address addr = base.getAddress();
4039 if (auto *ClassDef = dyn_cast<CXXRecordDecl>(rec)) {
4040 if (CGM.getCodeGenOpts().StrictVTablePointers &&
4041 ClassDef->isDynamicClass()) {
4042 // Getting to any field of dynamic object requires stripping dynamic
4043 // information provided by invariant.group. This is because accessing
4044 // fields may leak the real address of dynamic object, which could result
4045 // in miscompilation when leaked pointer would be compared.
4046 auto *stripped = Builder.CreateStripInvariantGroup(addr.getPointer());
4047 addr = Address(stripped, addr.getAlignment());
4051 unsigned RecordCVR = base.getVRQualifiers();
4052 if (rec->isUnion()) {
4053 // For unions, there is no pointer adjustment.
4054 assert(!FieldType->isReferenceType() && "union has reference member");
4055 if (CGM.getCodeGenOpts().StrictVTablePointers &&
4056 hasAnyVptr(FieldType, getContext()))
4057 // Because unions can easily skip invariant.barriers, we need to add
4058 // a barrier every time CXXRecord field with vptr is referenced.
4059 addr = Address(Builder.CreateLaunderInvariantGroup(addr.getPointer()),
4060 addr.getAlignment());
4062 if (IsInPreservedAIRegion) {
4063 // Remember the original union field index
4064 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateRecordType(
4065 getContext().getRecordType(rec), rec->getLocation());
4067 Builder.CreatePreserveUnionAccessIndex(
4068 addr.getPointer(), getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo),
4069 addr.getAlignment());
4073 if (!IsInPreservedAIRegion)
4074 // For structs, we GEP to the field that the record layout suggests.
4075 addr = emitAddrOfFieldStorage(*this, addr, field);
4077 // Remember the original struct field index
4078 addr = emitPreserveStructAccess(*this, addr, field);
4080 // If this is a reference field, load the reference right now.
4081 if (FieldType->isReferenceType()) {
4082 LValue RefLVal = MakeAddrLValue(addr, FieldType, FieldBaseInfo,
4084 if (RecordCVR & Qualifiers::Volatile)
4085 RefLVal.getQuals().addVolatile();
4086 addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo);
4088 // Qualifiers on the struct don't apply to the referencee.
4090 FieldType = FieldType->getPointeeType();
4094 // Make sure that the address is pointing to the right type. This is critical
4095 // for both unions and structs. A union needs a bitcast, a struct element
4096 // will need a bitcast if the LLVM type laid out doesn't match the desired
4098 addr = Builder.CreateElementBitCast(
4099 addr, CGM.getTypes().ConvertTypeForMem(FieldType), field->getName());
4101 if (field->hasAttr<AnnotateAttr>())
4102 addr = EmitFieldAnnotations(field, addr);
4104 LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
4105 LV.getQuals().addCVRQualifiers(RecordCVR);
4107 // __weak attribute on a field is ignored.
4108 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
4109 LV.getQuals().removeObjCGCAttr();
4115 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
4116 const FieldDecl *Field) {
4117 QualType FieldType = Field->getType();
4119 if (!FieldType->isReferenceType())
4120 return EmitLValueForField(Base, Field);
4122 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(), Field);
4124 // Make sure that the address is pointing to the right type.
4125 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
4126 V = Builder.CreateElementBitCast(V, llvmType, Field->getName());
4128 // TODO: Generate TBAA information that describes this access as a structure
4129 // member access and not just an access to an object of the field's type. This
4130 // should be similar to what we do in EmitLValueForField().
4131 LValueBaseInfo BaseInfo = Base.getBaseInfo();
4132 AlignmentSource FieldAlignSource = BaseInfo.getAlignmentSource();
4133 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(FieldAlignSource));
4134 return MakeAddrLValue(V, FieldType, FieldBaseInfo,
4135 CGM.getTBAAInfoForSubobject(Base, FieldType));
4138 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
4139 if (E->isFileScope()) {
4140 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
4141 return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl);
4143 if (E->getType()->isVariablyModifiedType())
4144 // make sure to emit the VLA size.
4145 EmitVariablyModifiedType(E->getType());
4147 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
4148 const Expr *InitExpr = E->getInitializer();
4149 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl);
4151 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
4157 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
4158 if (!E->isGLValue())
4159 // Initializing an aggregate temporary in C++11: T{...}.
4160 return EmitAggExprToLValue(E);
4162 // An lvalue initializer list must be initializing a reference.
4163 assert(E->isTransparent() && "non-transparent glvalue init list");
4164 return EmitLValue(E->getInit(0));
4167 /// Emit the operand of a glvalue conditional operator. This is either a glvalue
4168 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no
4169 /// LValue is returned and the current block has been terminated.
4170 static Optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
4171 const Expr *Operand) {
4172 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
4173 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
4177 return CGF.EmitLValue(Operand);
4180 LValue CodeGenFunction::
4181 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
4182 if (!expr->isGLValue()) {
4183 // ?: here should be an aggregate.
4184 assert(hasAggregateEvaluationKind(expr->getType()) &&
4185 "Unexpected conditional operator!");
4186 return EmitAggExprToLValue(expr);
4189 OpaqueValueMapping binding(*this, expr);
4191 const Expr *condExpr = expr->getCond();
4193 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
4194 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
4195 if (!CondExprBool) std::swap(live, dead);
4197 if (!ContainsLabel(dead)) {
4198 // If the true case is live, we need to track its region.
4200 incrementProfileCounter(expr);
4201 return EmitLValue(live);
4205 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
4206 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
4207 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
4209 ConditionalEvaluation eval(*this);
4210 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock, getProfileCount(expr));
4212 // Any temporaries created here are conditional.
4213 EmitBlock(lhsBlock);
4214 incrementProfileCounter(expr);
4216 Optional<LValue> lhs =
4217 EmitLValueOrThrowExpression(*this, expr->getTrueExpr());
4220 if (lhs && !lhs->isSimple())
4221 return EmitUnsupportedLValue(expr, "conditional operator");
4223 lhsBlock = Builder.GetInsertBlock();
4225 Builder.CreateBr(contBlock);
4227 // Any temporaries created here are conditional.
4228 EmitBlock(rhsBlock);
4230 Optional<LValue> rhs =
4231 EmitLValueOrThrowExpression(*this, expr->getFalseExpr());
4233 if (rhs && !rhs->isSimple())
4234 return EmitUnsupportedLValue(expr, "conditional operator");
4235 rhsBlock = Builder.GetInsertBlock();
4237 EmitBlock(contBlock);
4240 llvm::PHINode *phi = Builder.CreatePHI(lhs->getPointer()->getType(),
4242 phi->addIncoming(lhs->getPointer(), lhsBlock);
4243 phi->addIncoming(rhs->getPointer(), rhsBlock);
4244 Address result(phi, std::min(lhs->getAlignment(), rhs->getAlignment()));
4245 AlignmentSource alignSource =
4246 std::max(lhs->getBaseInfo().getAlignmentSource(),
4247 rhs->getBaseInfo().getAlignmentSource());
4248 TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForConditionalOperator(
4249 lhs->getTBAAInfo(), rhs->getTBAAInfo());
4250 return MakeAddrLValue(result, expr->getType(), LValueBaseInfo(alignSource),
4253 assert((lhs || rhs) &&
4254 "both operands of glvalue conditional are throw-expressions?");
4255 return lhs ? *lhs : *rhs;
4259 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
4260 /// type. If the cast is to a reference, we can have the usual lvalue result,
4261 /// otherwise if a cast is needed by the code generator in an lvalue context,
4262 /// then it must mean that we need the address of an aggregate in order to
4263 /// access one of its members. This can happen for all the reasons that casts
4264 /// are permitted with aggregate result, including noop aggregate casts, and
4265 /// cast from scalar to union.
4266 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
4267 switch (E->getCastKind()) {
4270 case CK_LValueToRValueBitCast:
4271 case CK_ArrayToPointerDecay:
4272 case CK_FunctionToPointerDecay:
4273 case CK_NullToMemberPointer:
4274 case CK_NullToPointer:
4275 case CK_IntegralToPointer:
4276 case CK_PointerToIntegral:
4277 case CK_PointerToBoolean:
4278 case CK_VectorSplat:
4279 case CK_IntegralCast:
4280 case CK_BooleanToSignedIntegral:
4281 case CK_IntegralToBoolean:
4282 case CK_IntegralToFloating:
4283 case CK_FloatingToIntegral:
4284 case CK_FloatingToBoolean:
4285 case CK_FloatingCast:
4286 case CK_FloatingRealToComplex:
4287 case CK_FloatingComplexToReal:
4288 case CK_FloatingComplexToBoolean:
4289 case CK_FloatingComplexCast:
4290 case CK_FloatingComplexToIntegralComplex:
4291 case CK_IntegralRealToComplex:
4292 case CK_IntegralComplexToReal:
4293 case CK_IntegralComplexToBoolean:
4294 case CK_IntegralComplexCast:
4295 case CK_IntegralComplexToFloatingComplex:
4296 case CK_DerivedToBaseMemberPointer:
4297 case CK_BaseToDerivedMemberPointer:
4298 case CK_MemberPointerToBoolean:
4299 case CK_ReinterpretMemberPointer:
4300 case CK_AnyPointerToBlockPointerCast:
4301 case CK_ARCProduceObject:
4302 case CK_ARCConsumeObject:
4303 case CK_ARCReclaimReturnedObject:
4304 case CK_ARCExtendBlockObject:
4305 case CK_CopyAndAutoreleaseBlockObject:
4306 case CK_IntToOCLSampler:
4307 case CK_FixedPointCast:
4308 case CK_FixedPointToBoolean:
4309 case CK_FixedPointToIntegral:
4310 case CK_IntegralToFixedPoint:
4311 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
4314 llvm_unreachable("dependent cast kind in IR gen!");
4316 case CK_BuiltinFnToFnPtr:
4317 llvm_unreachable("builtin functions are handled elsewhere");
4319 // These are never l-values; just use the aggregate emission code.
4320 case CK_NonAtomicToAtomic:
4321 case CK_AtomicToNonAtomic:
4322 return EmitAggExprToLValue(E);
4325 LValue LV = EmitLValue(E->getSubExpr());
4326 Address V = LV.getAddress();
4327 const auto *DCE = cast<CXXDynamicCastExpr>(E);
4328 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType());
4331 case CK_ConstructorConversion:
4332 case CK_UserDefinedConversion:
4333 case CK_CPointerToObjCPointerCast:
4334 case CK_BlockPointerToObjCPointerCast:
4336 case CK_LValueToRValue:
4337 return EmitLValue(E->getSubExpr());
4339 case CK_UncheckedDerivedToBase:
4340 case CK_DerivedToBase: {
4341 const RecordType *DerivedClassTy =
4342 E->getSubExpr()->getType()->getAs<RecordType>();
4343 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
4345 LValue LV = EmitLValue(E->getSubExpr());
4346 Address This = LV.getAddress();
4348 // Perform the derived-to-base conversion
4349 Address Base = GetAddressOfBaseClass(
4350 This, DerivedClassDecl, E->path_begin(), E->path_end(),
4351 /*NullCheckValue=*/false, E->getExprLoc());
4353 // TODO: Support accesses to members of base classes in TBAA. For now, we
4354 // conservatively pretend that the complete object is of the base class
4356 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo(),
4357 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4360 return EmitAggExprToLValue(E);
4361 case CK_BaseToDerived: {
4362 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
4363 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
4365 LValue LV = EmitLValue(E->getSubExpr());
4367 // Perform the base-to-derived conversion
4369 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
4370 E->path_begin(), E->path_end(),
4371 /*NullCheckValue=*/false);
4373 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
4374 // performed and the object is not of the derived type.
4375 if (sanitizePerformTypeCheck())
4376 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
4377 Derived.getPointer(), E->getType());
4379 if (SanOpts.has(SanitizerKind::CFIDerivedCast))
4380 EmitVTablePtrCheckForCast(E->getType(), Derived.getPointer(),
4381 /*MayBeNull=*/false, CFITCK_DerivedCast,
4384 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo(),
4385 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4387 case CK_LValueBitCast: {
4388 // This must be a reinterpret_cast (or c-style equivalent).
4389 const auto *CE = cast<ExplicitCastExpr>(E);
4391 CGM.EmitExplicitCastExprType(CE, this);
4392 LValue LV = EmitLValue(E->getSubExpr());
4393 Address V = Builder.CreateBitCast(LV.getAddress(),
4394 ConvertType(CE->getTypeAsWritten()));
4396 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast))
4397 EmitVTablePtrCheckForCast(E->getType(), V.getPointer(),
4398 /*MayBeNull=*/false, CFITCK_UnrelatedCast,
4401 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
4402 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4404 case CK_AddressSpaceConversion: {
4405 LValue LV = EmitLValue(E->getSubExpr());
4406 QualType DestTy = getContext().getPointerType(E->getType());
4407 llvm::Value *V = getTargetHooks().performAddrSpaceCast(
4408 *this, LV.getPointer(), E->getSubExpr()->getType().getAddressSpace(),
4409 E->getType().getAddressSpace(), ConvertType(DestTy));
4410 return MakeAddrLValue(Address(V, LV.getAddress().getAlignment()),
4411 E->getType(), LV.getBaseInfo(), LV.getTBAAInfo());
4413 case CK_ObjCObjectLValueCast: {
4414 LValue LV = EmitLValue(E->getSubExpr());
4415 Address V = Builder.CreateElementBitCast(LV.getAddress(),
4416 ConvertType(E->getType()));
4417 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
4418 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4420 case CK_ZeroToOCLOpaqueType:
4421 llvm_unreachable("NULL to OpenCL opaque type lvalue cast is not valid");
4424 llvm_unreachable("Unhandled lvalue cast kind?");
4427 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
4428 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
4429 return getOrCreateOpaqueLValueMapping(e);
4433 CodeGenFunction::getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e) {
4434 assert(OpaqueValueMapping::shouldBindAsLValue(e));
4436 llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator
4437 it = OpaqueLValues.find(e);
4439 if (it != OpaqueLValues.end())
4442 assert(e->isUnique() && "LValue for a nonunique OVE hasn't been emitted");
4443 return EmitLValue(e->getSourceExpr());
4447 CodeGenFunction::getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e) {
4448 assert(!OpaqueValueMapping::shouldBindAsLValue(e));
4450 llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator
4451 it = OpaqueRValues.find(e);
4453 if (it != OpaqueRValues.end())
4456 assert(e->isUnique() && "RValue for a nonunique OVE hasn't been emitted");
4457 return EmitAnyExpr(e->getSourceExpr());
4460 RValue CodeGenFunction::EmitRValueForField(LValue LV,
4461 const FieldDecl *FD,
4462 SourceLocation Loc) {
4463 QualType FT = FD->getType();
4464 LValue FieldLV = EmitLValueForField(LV, FD);
4465 switch (getEvaluationKind(FT)) {
4467 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
4469 return FieldLV.asAggregateRValue();
4471 // This routine is used to load fields one-by-one to perform a copy, so
4472 // don't load reference fields.
4473 if (FD->getType()->isReferenceType())
4474 return RValue::get(FieldLV.getPointer());
4475 return EmitLoadOfLValue(FieldLV, Loc);
4477 llvm_unreachable("bad evaluation kind");
4480 //===--------------------------------------------------------------------===//
4481 // Expression Emission
4482 //===--------------------------------------------------------------------===//
4484 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
4485 ReturnValueSlot ReturnValue) {
4486 // Builtins never have block type.
4487 if (E->getCallee()->getType()->isBlockPointerType())
4488 return EmitBlockCallExpr(E, ReturnValue);
4490 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
4491 return EmitCXXMemberCallExpr(CE, ReturnValue);
4493 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
4494 return EmitCUDAKernelCallExpr(CE, ReturnValue);
4496 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
4497 if (const CXXMethodDecl *MD =
4498 dyn_cast_or_null<CXXMethodDecl>(CE->getCalleeDecl()))
4499 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
4501 CGCallee callee = EmitCallee(E->getCallee());
4503 if (callee.isBuiltin()) {
4504 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(),
4508 if (callee.isPseudoDestructor()) {
4509 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr());
4512 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue);
4515 /// Emit a CallExpr without considering whether it might be a subclass.
4516 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E,
4517 ReturnValueSlot ReturnValue) {
4518 CGCallee Callee = EmitCallee(E->getCallee());
4519 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue);
4522 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, const FunctionDecl *FD) {
4523 if (auto builtinID = FD->getBuiltinID()) {
4524 return CGCallee::forBuiltin(builtinID, FD);
4527 llvm::Constant *calleePtr = EmitFunctionDeclPointer(CGF.CGM, FD);
4528 return CGCallee::forDirect(calleePtr, GlobalDecl(FD));
4531 CGCallee CodeGenFunction::EmitCallee(const Expr *E) {
4532 E = E->IgnoreParens();
4534 // Look through function-to-pointer decay.
4535 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) {
4536 if (ICE->getCastKind() == CK_FunctionToPointerDecay ||
4537 ICE->getCastKind() == CK_BuiltinFnToFnPtr) {
4538 return EmitCallee(ICE->getSubExpr());
4541 // Resolve direct calls.
4542 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) {
4543 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
4544 return EmitDirectCallee(*this, FD);
4546 } else if (auto ME = dyn_cast<MemberExpr>(E)) {
4547 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) {
4548 EmitIgnoredExpr(ME->getBase());
4549 return EmitDirectCallee(*this, FD);
4552 // Look through template substitutions.
4553 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
4554 return EmitCallee(NTTP->getReplacement());
4556 // Treat pseudo-destructor calls differently.
4557 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) {
4558 return CGCallee::forPseudoDestructor(PDE);
4561 // Otherwise, we have an indirect reference.
4562 llvm::Value *calleePtr;
4563 QualType functionType;
4564 if (auto ptrType = E->getType()->getAs<PointerType>()) {
4565 calleePtr = EmitScalarExpr(E);
4566 functionType = ptrType->getPointeeType();
4568 functionType = E->getType();
4569 calleePtr = EmitLValue(E).getPointer();
4571 assert(functionType->isFunctionType());
4574 if (const auto *VD =
4575 dyn_cast_or_null<VarDecl>(E->getReferencedDeclOfCallee()))
4576 GD = GlobalDecl(VD);
4578 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(), GD);
4579 CGCallee callee(calleeInfo, calleePtr);
4583 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
4584 // Comma expressions just emit their LHS then their RHS as an l-value.
4585 if (E->getOpcode() == BO_Comma) {
4586 EmitIgnoredExpr(E->getLHS());
4587 EnsureInsertPoint();
4588 return EmitLValue(E->getRHS());
4591 if (E->getOpcode() == BO_PtrMemD ||
4592 E->getOpcode() == BO_PtrMemI)
4593 return EmitPointerToDataMemberBinaryExpr(E);
4595 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
4597 // Note that in all of these cases, __block variables need the RHS
4598 // evaluated first just in case the variable gets moved by the RHS.
4600 switch (getEvaluationKind(E->getType())) {
4602 switch (E->getLHS()->getType().getObjCLifetime()) {
4603 case Qualifiers::OCL_Strong:
4604 return EmitARCStoreStrong(E, /*ignored*/ false).first;
4606 case Qualifiers::OCL_Autoreleasing:
4607 return EmitARCStoreAutoreleasing(E).first;
4609 // No reason to do any of these differently.
4610 case Qualifiers::OCL_None:
4611 case Qualifiers::OCL_ExplicitNone:
4612 case Qualifiers::OCL_Weak:
4616 RValue RV = EmitAnyExpr(E->getRHS());
4617 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
4619 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc());
4620 EmitStoreThroughLValue(RV, LV);
4625 return EmitComplexAssignmentLValue(E);
4628 return EmitAggExprToLValue(E);
4630 llvm_unreachable("bad evaluation kind");
4633 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
4634 RValue RV = EmitCallExpr(E);
4637 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4638 AlignmentSource::Decl);
4640 assert(E->getCallReturnType(getContext())->isReferenceType() &&
4641 "Can't have a scalar return unless the return type is a "
4644 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4647 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
4648 // FIXME: This shouldn't require another copy.
4649 return EmitAggExprToLValue(E);
4652 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
4653 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
4654 && "binding l-value to type which needs a temporary");
4655 AggValueSlot Slot = CreateAggTemp(E->getType());
4656 EmitCXXConstructExpr(E, Slot);
4657 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4661 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
4662 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType());
4665 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
4666 return Builder.CreateElementBitCast(CGM.GetAddrOfUuidDescriptor(E),
4667 ConvertType(E->getType()));
4670 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
4671 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(),
4672 AlignmentSource::Decl);
4676 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
4677 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4678 Slot.setExternallyDestructed();
4679 EmitAggExpr(E->getSubExpr(), Slot);
4680 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress());
4681 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4684 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
4685 RValue RV = EmitObjCMessageExpr(E);
4688 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4689 AlignmentSource::Decl);
4691 assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
4692 "Can't have a scalar return unless the return type is a "
4695 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4698 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
4700 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector());
4701 return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl);
4704 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
4705 const ObjCIvarDecl *Ivar) {
4706 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
4709 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
4710 llvm::Value *BaseValue,
4711 const ObjCIvarDecl *Ivar,
4712 unsigned CVRQualifiers) {
4713 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
4714 Ivar, CVRQualifiers);
4717 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
4718 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
4719 llvm::Value *BaseValue = nullptr;
4720 const Expr *BaseExpr = E->getBase();
4721 Qualifiers BaseQuals;
4724 BaseValue = EmitScalarExpr(BaseExpr);
4725 ObjectTy = BaseExpr->getType()->getPointeeType();
4726 BaseQuals = ObjectTy.getQualifiers();
4728 LValue BaseLV = EmitLValue(BaseExpr);
4729 BaseValue = BaseLV.getPointer();
4730 ObjectTy = BaseExpr->getType();
4731 BaseQuals = ObjectTy.getQualifiers();
4735 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
4736 BaseQuals.getCVRQualifiers());
4737 setObjCGCLValueClass(getContext(), E, LV);
4741 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
4742 // Can only get l-value for message expression returning aggregate type
4743 RValue RV = EmitAnyExprToTemp(E);
4744 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4745 AlignmentSource::Decl);
4748 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee,
4749 const CallExpr *E, ReturnValueSlot ReturnValue,
4750 llvm::Value *Chain) {
4751 // Get the actual function type. The callee type will always be a pointer to
4752 // function type or a block pointer type.
4753 assert(CalleeType->isFunctionPointerType() &&
4754 "Call must have function pointer type!");
4756 const Decl *TargetDecl =
4757 OrigCallee.getAbstractInfo().getCalleeDecl().getDecl();
4759 CalleeType = getContext().getCanonicalType(CalleeType);
4761 auto PointeeType = cast<PointerType>(CalleeType)->getPointeeType();
4763 CGCallee Callee = OrigCallee;
4765 if (getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function) &&
4766 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4767 if (llvm::Constant *PrefixSig =
4768 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
4769 SanitizerScope SanScope(this);
4770 // Remove any (C++17) exception specifications, to allow calling e.g. a
4771 // noexcept function through a non-noexcept pointer.
4773 getContext().getFunctionTypeWithExceptionSpec(PointeeType, EST_None);
4774 llvm::Constant *FTRTTIConst =
4775 CGM.GetAddrOfRTTIDescriptor(ProtoTy, /*ForEH=*/true);
4776 llvm::Type *PrefixStructTyElems[] = {PrefixSig->getType(), Int32Ty};
4777 llvm::StructType *PrefixStructTy = llvm::StructType::get(
4778 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
4780 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4782 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
4783 CalleePtr, llvm::PointerType::getUnqual(PrefixStructTy));
4784 llvm::Value *CalleeSigPtr =
4785 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 0);
4786 llvm::Value *CalleeSig =
4787 Builder.CreateAlignedLoad(CalleeSigPtr, getIntAlign());
4788 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
4790 llvm::BasicBlock *Cont = createBasicBlock("cont");
4791 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
4792 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
4794 EmitBlock(TypeCheck);
4795 llvm::Value *CalleeRTTIPtr =
4796 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 1);
4797 llvm::Value *CalleeRTTIEncoded =
4798 Builder.CreateAlignedLoad(CalleeRTTIPtr, getPointerAlign());
4799 llvm::Value *CalleeRTTI =
4800 DecodeAddrUsedInPrologue(CalleePtr, CalleeRTTIEncoded);
4801 llvm::Value *CalleeRTTIMatch =
4802 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
4803 llvm::Constant *StaticData[] = {EmitCheckSourceLocation(E->getBeginLoc()),
4804 EmitCheckTypeDescriptor(CalleeType)};
4805 EmitCheck(std::make_pair(CalleeRTTIMatch, SanitizerKind::Function),
4806 SanitizerHandler::FunctionTypeMismatch, StaticData,
4807 {CalleePtr, CalleeRTTI, FTRTTIConst});
4809 Builder.CreateBr(Cont);
4814 const auto *FnType = cast<FunctionType>(PointeeType);
4816 // If we are checking indirect calls and this call is indirect, check that the
4817 // function pointer is a member of the bit set for the function type.
4818 if (SanOpts.has(SanitizerKind::CFIICall) &&
4819 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4820 SanitizerScope SanScope(this);
4821 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
4824 if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers)
4825 MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0));
4827 MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
4829 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD);
4831 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4832 llvm::Value *CastedCallee = Builder.CreateBitCast(CalleePtr, Int8PtrTy);
4833 llvm::Value *TypeTest = Builder.CreateCall(
4834 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CastedCallee, TypeId});
4836 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD);
4837 llvm::Constant *StaticData[] = {
4838 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall),
4839 EmitCheckSourceLocation(E->getBeginLoc()),
4840 EmitCheckTypeDescriptor(QualType(FnType, 0)),
4842 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) {
4843 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId,
4844 CastedCallee, StaticData);
4846 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall),
4847 SanitizerHandler::CFICheckFail, StaticData,
4848 {CastedCallee, llvm::UndefValue::get(IntPtrTy)});
4854 Args.add(RValue::get(Builder.CreateBitCast(Chain, CGM.VoidPtrTy)),
4855 CGM.getContext().VoidPtrTy);
4857 // C++17 requires that we evaluate arguments to a call using assignment syntax
4858 // right-to-left, and that we evaluate arguments to certain other operators
4859 // left-to-right. Note that we allow this to override the order dictated by
4860 // the calling convention on the MS ABI, which means that parameter
4861 // destruction order is not necessarily reverse construction order.
4862 // FIXME: Revisit this based on C++ committee response to unimplementability.
4863 EvaluationOrder Order = EvaluationOrder::Default;
4864 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) {
4865 if (OCE->isAssignmentOp())
4866 Order = EvaluationOrder::ForceRightToLeft;
4868 switch (OCE->getOperator()) {
4870 case OO_GreaterGreater:
4875 Order = EvaluationOrder::ForceLeftToRight;
4883 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(),
4884 E->getDirectCallee(), /*ParamsToSkip*/ 0, Order);
4886 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall(
4887 Args, FnType, /*ChainCall=*/Chain);
4890 // If the expression that denotes the called function has a type
4891 // that does not include a prototype, [the default argument
4892 // promotions are performed]. If the number of arguments does not
4893 // equal the number of parameters, the behavior is undefined. If
4894 // the function is defined with a type that includes a prototype,
4895 // and either the prototype ends with an ellipsis (, ...) or the
4896 // types of the arguments after promotion are not compatible with
4897 // the types of the parameters, the behavior is undefined. If the
4898 // function is defined with a type that does not include a
4899 // prototype, and the types of the arguments after promotion are
4900 // not compatible with those of the parameters after promotion,
4901 // the behavior is undefined [except in some trivial cases].
4902 // That is, in the general case, we should assume that a call
4903 // through an unprototyped function type works like a *non-variadic*
4904 // call. The way we make this work is to cast to the exact type
4905 // of the promoted arguments.
4907 // Chain calls use this same code path to add the invisible chain parameter
4908 // to the function type.
4909 if (isa<FunctionNoProtoType>(FnType) || Chain) {
4910 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
4911 CalleeTy = CalleeTy->getPointerTo();
4913 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4914 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast");
4915 Callee.setFunctionPointer(CalleePtr);
4918 llvm::CallBase *CallOrInvoke = nullptr;
4919 RValue Call = EmitCall(FnInfo, Callee, ReturnValue, Args, &CallOrInvoke,
4922 // Generate function declaration DISuprogram in order to be used
4923 // in debug info about call sites.
4924 if (CGDebugInfo *DI = getDebugInfo()) {
4925 if (auto *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl))
4926 DI->EmitFuncDeclForCallSite(CallOrInvoke, QualType(FnType, 0),
4933 LValue CodeGenFunction::
4934 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
4935 Address BaseAddr = Address::invalid();
4936 if (E->getOpcode() == BO_PtrMemI) {
4937 BaseAddr = EmitPointerWithAlignment(E->getLHS());
4939 BaseAddr = EmitLValue(E->getLHS()).getAddress();
4942 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
4944 const MemberPointerType *MPT
4945 = E->getRHS()->getType()->getAs<MemberPointerType>();
4947 LValueBaseInfo BaseInfo;
4948 TBAAAccessInfo TBAAInfo;
4949 Address MemberAddr =
4950 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo,
4953 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo, TBAAInfo);
4956 /// Given the address of a temporary variable, produce an r-value of
4958 RValue CodeGenFunction::convertTempToRValue(Address addr,
4960 SourceLocation loc) {
4961 LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl);
4962 switch (getEvaluationKind(type)) {
4964 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
4966 return lvalue.asAggregateRValue();
4968 return RValue::get(EmitLoadOfScalar(lvalue, loc));
4970 llvm_unreachable("bad evaluation kind");
4973 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
4974 assert(Val->getType()->isFPOrFPVectorTy());
4975 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
4978 llvm::MDBuilder MDHelper(getLLVMContext());
4979 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
4981 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
4985 struct LValueOrRValue {
4991 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
4992 const PseudoObjectExpr *E,
4994 AggValueSlot slot) {
4995 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
4997 // Find the result expression, if any.
4998 const Expr *resultExpr = E->getResultExpr();
4999 LValueOrRValue result;
5001 for (PseudoObjectExpr::const_semantics_iterator
5002 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
5003 const Expr *semantic = *i;
5005 // If this semantic expression is an opaque value, bind it
5006 // to the result of its source expression.
5007 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
5008 // Skip unique OVEs.
5009 if (ov->isUnique()) {
5010 assert(ov != resultExpr &&
5011 "A unique OVE cannot be used as the result expression");
5015 // If this is the result expression, we may need to evaluate
5016 // directly into the slot.
5017 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
5019 if (ov == resultExpr && ov->isRValue() && !forLValue &&
5020 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
5021 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
5022 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(),
5023 AlignmentSource::Decl);
5024 opaqueData = OVMA::bind(CGF, ov, LV);
5025 result.RV = slot.asRValue();
5027 // Otherwise, emit as normal.
5029 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
5031 // If this is the result, also evaluate the result now.
5032 if (ov == resultExpr) {
5034 result.LV = CGF.EmitLValue(ov);
5036 result.RV = CGF.EmitAnyExpr(ov, slot);
5040 opaques.push_back(opaqueData);
5042 // Otherwise, if the expression is the result, evaluate it
5043 // and remember the result.
5044 } else if (semantic == resultExpr) {
5046 result.LV = CGF.EmitLValue(semantic);
5048 result.RV = CGF.EmitAnyExpr(semantic, slot);
5050 // Otherwise, evaluate the expression in an ignored context.
5052 CGF.EmitIgnoredExpr(semantic);
5056 // Unbind all the opaques now.
5057 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
5058 opaques[i].unbind(CGF);
5063 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
5064 AggValueSlot slot) {
5065 return emitPseudoObjectExpr(*this, E, false, slot).RV;
5068 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
5069 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;