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.getAsAlign());
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().getAsAlign());
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.getAsAlign());
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 with sanitizers which need
520 // more precise lifetime marks.
521 ConditionalEvaluation *OldConditional = nullptr;
522 CGBuilderTy::InsertPoint OldIP;
523 if (isInConditionalBranch() && !E->getType().isDestructedType() &&
524 !SanOpts.has(SanitizerKind::HWAddress) &&
525 !SanOpts.has(SanitizerKind::Memory) &&
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.
680 auto PtrToAlloca = dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCasts());
682 llvm::Value *True = llvm::ConstantInt::getTrue(getLLVMContext());
683 llvm::Value *IsNonNull = nullptr;
684 bool IsGuaranteedNonNull =
685 SkippedChecks.has(SanitizerKind::Null) || PtrToAlloca;
686 bool AllowNullPointers = isNullPointerAllowed(TCK);
687 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) &&
688 !IsGuaranteedNonNull) {
689 // The glvalue must not be an empty glvalue.
690 IsNonNull = Builder.CreateIsNotNull(Ptr);
692 // The IR builder can constant-fold the null check if the pointer points to
694 IsGuaranteedNonNull = IsNonNull == True;
696 // Skip the null check if the pointer is known to be non-null.
697 if (!IsGuaranteedNonNull) {
698 if (AllowNullPointers) {
699 // When performing pointer casts, it's OK if the value is null.
700 // Skip the remaining checks in that case.
701 Done = createBasicBlock("null");
702 llvm::BasicBlock *Rest = createBasicBlock("not.null");
703 Builder.CreateCondBr(IsNonNull, Rest, Done);
706 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null));
711 if (SanOpts.has(SanitizerKind::ObjectSize) &&
712 !SkippedChecks.has(SanitizerKind::ObjectSize) &&
713 !Ty->isIncompleteType()) {
714 uint64_t TySize = getContext().getTypeSizeInChars(Ty).getQuantity();
715 llvm::Value *Size = llvm::ConstantInt::get(IntPtrTy, TySize);
717 Size = Builder.CreateMul(Size, ArraySize);
719 // Degenerate case: new X[0] does not need an objectsize check.
720 llvm::Constant *ConstantSize = dyn_cast<llvm::Constant>(Size);
721 if (!ConstantSize || !ConstantSize->isNullValue()) {
722 // The glvalue must refer to a large enough storage region.
723 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
725 // FIXME: Get object address space
726 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
727 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
728 llvm::Value *Min = Builder.getFalse();
729 llvm::Value *NullIsUnknown = Builder.getFalse();
730 llvm::Value *Dynamic = Builder.getFalse();
731 llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy);
732 llvm::Value *LargeEnough = Builder.CreateICmpUGE(
733 Builder.CreateCall(F, {CastAddr, Min, NullIsUnknown, Dynamic}), Size);
734 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
738 uint64_t AlignVal = 0;
739 llvm::Value *PtrAsInt = nullptr;
741 if (SanOpts.has(SanitizerKind::Alignment) &&
742 !SkippedChecks.has(SanitizerKind::Alignment)) {
743 AlignVal = Alignment.getQuantity();
744 if (!Ty->isIncompleteType() && !AlignVal)
745 AlignVal = getContext().getTypeAlignInChars(Ty).getQuantity();
747 // The glvalue must be suitably aligned.
749 (!PtrToAlloca || PtrToAlloca->getAlignment() < AlignVal)) {
750 PtrAsInt = Builder.CreatePtrToInt(Ptr, IntPtrTy);
751 llvm::Value *Align = Builder.CreateAnd(
752 PtrAsInt, llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
753 llvm::Value *Aligned =
754 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
756 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment));
760 if (Checks.size() > 0) {
761 // Make sure we're not losing information. Alignment needs to be a power of
763 assert(!AlignVal || (uint64_t)1 << llvm::Log2_64(AlignVal) == AlignVal);
764 llvm::Constant *StaticData[] = {
765 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty),
766 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2_64(AlignVal) : 1),
767 llvm::ConstantInt::get(Int8Ty, TCK)};
768 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData,
769 PtrAsInt ? PtrAsInt : Ptr);
772 // If possible, check that the vptr indicates that there is a subobject of
773 // type Ty at offset zero within this object.
775 // C++11 [basic.life]p5,6:
776 // [For storage which does not refer to an object within its lifetime]
777 // The program has undefined behavior if:
778 // -- the [pointer or glvalue] is used to access a non-static data member
779 // or call a non-static member function
780 if (SanOpts.has(SanitizerKind::Vptr) &&
781 !SkippedChecks.has(SanitizerKind::Vptr) && isVptrCheckRequired(TCK, Ty)) {
782 // Ensure that the pointer is non-null before loading it. If there is no
783 // compile-time guarantee, reuse the run-time null check or emit a new one.
784 if (!IsGuaranteedNonNull) {
786 IsNonNull = Builder.CreateIsNotNull(Ptr);
788 Done = createBasicBlock("vptr.null");
789 llvm::BasicBlock *VptrNotNull = createBasicBlock("vptr.not.null");
790 Builder.CreateCondBr(IsNonNull, VptrNotNull, Done);
791 EmitBlock(VptrNotNull);
794 // Compute a hash of the mangled name of the type.
796 // FIXME: This is not guaranteed to be deterministic! Move to a
797 // fingerprinting mechanism once LLVM provides one. For the time
798 // being the implementation happens to be deterministic.
799 SmallString<64> MangledName;
800 llvm::raw_svector_ostream Out(MangledName);
801 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
804 // Blacklist based on the mangled type.
805 if (!CGM.getContext().getSanitizerBlacklist().isBlacklistedType(
806 SanitizerKind::Vptr, Out.str())) {
807 llvm::hash_code TypeHash = hash_value(Out.str());
809 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
810 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
811 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
812 Address VPtrAddr(Builder.CreateBitCast(Ptr, VPtrTy), getPointerAlign());
813 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
814 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
816 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
817 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
819 // Look the hash up in our cache.
820 const int CacheSize = 128;
821 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
822 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
823 "__ubsan_vptr_type_cache");
824 llvm::Value *Slot = Builder.CreateAnd(Hash,
825 llvm::ConstantInt::get(IntPtrTy,
827 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
828 llvm::Value *CacheVal =
829 Builder.CreateAlignedLoad(Builder.CreateInBoundsGEP(Cache, Indices),
832 // If the hash isn't in the cache, call a runtime handler to perform the
833 // hard work of checking whether the vptr is for an object of the right
834 // type. This will either fill in the cache and return, or produce a
836 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash);
837 llvm::Constant *StaticData[] = {
838 EmitCheckSourceLocation(Loc),
839 EmitCheckTypeDescriptor(Ty),
840 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
841 llvm::ConstantInt::get(Int8Ty, TCK)
843 llvm::Value *DynamicData[] = { Ptr, Hash };
844 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr),
845 SanitizerHandler::DynamicTypeCacheMiss, StaticData,
851 Builder.CreateBr(Done);
856 /// Determine whether this expression refers to a flexible array member in a
857 /// struct. We disable array bounds checks for such members.
858 static bool isFlexibleArrayMemberExpr(const Expr *E) {
859 // For compatibility with existing code, we treat arrays of length 0 or
860 // 1 as flexible array members.
861 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
862 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
863 if (CAT->getSize().ugt(1))
865 } else if (!isa<IncompleteArrayType>(AT))
868 E = E->IgnoreParens();
870 // A flexible array member must be the last member in the class.
871 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
872 // FIXME: If the base type of the member expr is not FD->getParent(),
873 // this should not be treated as a flexible array member access.
874 if (const auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
875 RecordDecl::field_iterator FI(
876 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
877 return ++FI == FD->getParent()->field_end();
879 } else if (const auto *IRE = dyn_cast<ObjCIvarRefExpr>(E)) {
880 return IRE->getDecl()->getNextIvar() == nullptr;
886 llvm::Value *CodeGenFunction::LoadPassedObjectSize(const Expr *E,
888 ASTContext &C = getContext();
889 uint64_t EltSize = C.getTypeSizeInChars(EltTy).getQuantity();
893 auto *ArrayDeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts());
897 auto *ParamDecl = dyn_cast<ParmVarDecl>(ArrayDeclRef->getDecl());
901 auto *POSAttr = ParamDecl->getAttr<PassObjectSizeAttr>();
905 // Don't load the size if it's a lower bound.
906 int POSType = POSAttr->getType();
907 if (POSType != 0 && POSType != 1)
910 // Find the implicit size parameter.
911 auto PassedSizeIt = SizeArguments.find(ParamDecl);
912 if (PassedSizeIt == SizeArguments.end())
915 const ImplicitParamDecl *PassedSizeDecl = PassedSizeIt->second;
916 assert(LocalDeclMap.count(PassedSizeDecl) && "Passed size not loadable");
917 Address AddrOfSize = LocalDeclMap.find(PassedSizeDecl)->second;
918 llvm::Value *SizeInBytes = EmitLoadOfScalar(AddrOfSize, /*Volatile=*/false,
919 C.getSizeType(), E->getExprLoc());
920 llvm::Value *SizeOfElement =
921 llvm::ConstantInt::get(SizeInBytes->getType(), EltSize);
922 return Builder.CreateUDiv(SizeInBytes, SizeOfElement);
925 /// If Base is known to point to the start of an array, return the length of
926 /// that array. Return 0 if the length cannot be determined.
927 static llvm::Value *getArrayIndexingBound(
928 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
929 // For the vector indexing extension, the bound is the number of elements.
930 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
931 IndexedType = Base->getType();
932 return CGF.Builder.getInt32(VT->getNumElements());
935 Base = Base->IgnoreParens();
937 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
938 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
939 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
940 IndexedType = CE->getSubExpr()->getType();
941 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
942 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
943 return CGF.Builder.getInt(CAT->getSize());
944 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
945 return CGF.getVLASize(VAT).NumElts;
946 // Ignore pass_object_size here. It's not applicable on decayed pointers.
950 QualType EltTy{Base->getType()->getPointeeOrArrayElementType(), 0};
951 if (llvm::Value *POS = CGF.LoadPassedObjectSize(Base, EltTy)) {
952 IndexedType = Base->getType();
959 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
960 llvm::Value *Index, QualType IndexType,
962 assert(SanOpts.has(SanitizerKind::ArrayBounds) &&
963 "should not be called unless adding bounds checks");
964 SanitizerScope SanScope(this);
966 QualType IndexedType;
967 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
971 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
972 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
973 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
975 llvm::Constant *StaticData[] = {
976 EmitCheckSourceLocation(E->getExprLoc()),
977 EmitCheckTypeDescriptor(IndexedType),
978 EmitCheckTypeDescriptor(IndexType)
980 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
981 : Builder.CreateICmpULE(IndexVal, BoundVal);
982 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds),
983 SanitizerHandler::OutOfBounds, StaticData, Index);
987 CodeGenFunction::ComplexPairTy CodeGenFunction::
988 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
989 bool isInc, bool isPre) {
990 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
992 llvm::Value *NextVal;
993 if (isa<llvm::IntegerType>(InVal.first->getType())) {
994 uint64_t AmountVal = isInc ? 1 : -1;
995 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
997 // Add the inc/dec to the real part.
998 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1000 QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType();
1001 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
1004 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
1006 // Add the inc/dec to the real part.
1007 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1010 ComplexPairTy IncVal(NextVal, InVal.second);
1012 // Store the updated result through the lvalue.
1013 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
1015 // If this is a postinc, return the value read from memory, otherwise use the
1017 return isPre ? IncVal : InVal;
1020 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E,
1021 CodeGenFunction *CGF) {
1022 // Bind VLAs in the cast type.
1023 if (CGF && E->getType()->isVariablyModifiedType())
1024 CGF->EmitVariablyModifiedType(E->getType());
1026 if (CGDebugInfo *DI = getModuleDebugInfo())
1027 DI->EmitExplicitCastType(E->getType());
1030 //===----------------------------------------------------------------------===//
1031 // LValue Expression Emission
1032 //===----------------------------------------------------------------------===//
1034 /// EmitPointerWithAlignment - Given an expression of pointer type, try to
1035 /// derive a more accurate bound on the alignment of the pointer.
1036 Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
1037 LValueBaseInfo *BaseInfo,
1038 TBAAAccessInfo *TBAAInfo) {
1039 // We allow this with ObjC object pointers because of fragile ABIs.
1040 assert(E->getType()->isPointerType() ||
1041 E->getType()->isObjCObjectPointerType());
1042 E = E->IgnoreParens();
1045 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
1046 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE))
1047 CGM.EmitExplicitCastExprType(ECE, this);
1049 switch (CE->getCastKind()) {
1050 // Non-converting casts (but not C's implicit conversion from void*).
1053 case CK_AddressSpaceConversion:
1054 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) {
1055 if (PtrTy->getPointeeType()->isVoidType())
1058 LValueBaseInfo InnerBaseInfo;
1059 TBAAAccessInfo InnerTBAAInfo;
1060 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(),
1063 if (BaseInfo) *BaseInfo = InnerBaseInfo;
1064 if (TBAAInfo) *TBAAInfo = InnerTBAAInfo;
1066 if (isa<ExplicitCastExpr>(CE)) {
1067 LValueBaseInfo TargetTypeBaseInfo;
1068 TBAAAccessInfo TargetTypeTBAAInfo;
1069 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(),
1070 &TargetTypeBaseInfo,
1071 &TargetTypeTBAAInfo);
1073 *TBAAInfo = CGM.mergeTBAAInfoForCast(*TBAAInfo,
1074 TargetTypeTBAAInfo);
1075 // If the source l-value is opaque, honor the alignment of the
1077 if (InnerBaseInfo.getAlignmentSource() != AlignmentSource::Decl) {
1079 BaseInfo->mergeForCast(TargetTypeBaseInfo);
1080 Addr = Address(Addr.getPointer(), Align);
1084 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast) &&
1085 CE->getCastKind() == CK_BitCast) {
1086 if (auto PT = E->getType()->getAs<PointerType>())
1087 EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr.getPointer(),
1089 CodeGenFunction::CFITCK_UnrelatedCast,
1092 return CE->getCastKind() != CK_AddressSpaceConversion
1093 ? Builder.CreateBitCast(Addr, ConvertType(E->getType()))
1094 : Builder.CreateAddrSpaceCast(Addr,
1095 ConvertType(E->getType()));
1099 // Array-to-pointer decay.
1100 case CK_ArrayToPointerDecay:
1101 return EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo, TBAAInfo);
1103 // Derived-to-base conversions.
1104 case CK_UncheckedDerivedToBase:
1105 case CK_DerivedToBase: {
1106 // TODO: Support accesses to members of base classes in TBAA. For now, we
1107 // conservatively pretend that the complete object is of the base class
1110 *TBAAInfo = CGM.getTBAAAccessInfo(E->getType());
1111 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), BaseInfo);
1112 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl();
1113 return GetAddressOfBaseClass(Addr, Derived,
1114 CE->path_begin(), CE->path_end(),
1115 ShouldNullCheckClassCastValue(CE),
1119 // TODO: Is there any reason to treat base-to-derived conversions
1127 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
1128 if (UO->getOpcode() == UO_AddrOf) {
1129 LValue LV = EmitLValue(UO->getSubExpr());
1130 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
1131 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo();
1132 return LV.getAddress();
1136 // TODO: conditional operators, comma.
1138 // Otherwise, use the alignment of the type.
1139 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(), BaseInfo,
1141 return Address(EmitScalarExpr(E), Align);
1144 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
1145 if (Ty->isVoidType())
1146 return RValue::get(nullptr);
1148 switch (getEvaluationKind(Ty)) {
1151 ConvertType(Ty->castAs<ComplexType>()->getElementType());
1152 llvm::Value *U = llvm::UndefValue::get(EltTy);
1153 return RValue::getComplex(std::make_pair(U, U));
1156 // If this is a use of an undefined aggregate type, the aggregate must have an
1157 // identifiable address. Just because the contents of the value are undefined
1158 // doesn't mean that the address can't be taken and compared.
1159 case TEK_Aggregate: {
1160 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
1161 return RValue::getAggregate(DestPtr);
1165 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
1167 llvm_unreachable("bad evaluation kind");
1170 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
1172 ErrorUnsupported(E, Name);
1173 return GetUndefRValue(E->getType());
1176 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
1178 ErrorUnsupported(E, Name);
1179 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
1180 return MakeAddrLValue(Address(llvm::UndefValue::get(Ty), CharUnits::One()),
1184 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) {
1185 const Expr *Base = Obj;
1186 while (!isa<CXXThisExpr>(Base)) {
1187 // The result of a dynamic_cast can be null.
1188 if (isa<CXXDynamicCastExpr>(Base))
1191 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
1192 Base = CE->getSubExpr();
1193 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) {
1194 Base = PE->getSubExpr();
1195 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) {
1196 if (UO->getOpcode() == UO_Extension)
1197 Base = UO->getSubExpr();
1207 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
1209 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E))
1210 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
1213 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) {
1214 SanitizerSet SkippedChecks;
1215 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
1216 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase());
1218 SkippedChecks.set(SanitizerKind::Alignment, true);
1219 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase()))
1220 SkippedChecks.set(SanitizerKind::Null, true);
1222 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(),
1223 E->getType(), LV.getAlignment(), SkippedChecks);
1228 /// EmitLValue - Emit code to compute a designator that specifies the location
1229 /// of the expression.
1231 /// This can return one of two things: a simple address or a bitfield reference.
1232 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
1233 /// an LLVM pointer type.
1235 /// If this returns a bitfield reference, nothing about the pointee type of the
1236 /// LLVM value is known: For example, it may not be a pointer to an integer.
1238 /// If this returns a normal address, and if the lvalue's C type is fixed size,
1239 /// this method guarantees that the returned pointer type will point to an LLVM
1240 /// type of the same size of the lvalue's type. If the lvalue has a variable
1241 /// length type, this is not possible.
1243 LValue CodeGenFunction::EmitLValue(const Expr *E) {
1244 ApplyDebugLocation DL(*this, E);
1245 switch (E->getStmtClass()) {
1246 default: return EmitUnsupportedLValue(E, "l-value expression");
1248 case Expr::ObjCPropertyRefExprClass:
1249 llvm_unreachable("cannot emit a property reference directly");
1251 case Expr::ObjCSelectorExprClass:
1252 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
1253 case Expr::ObjCIsaExprClass:
1254 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
1255 case Expr::BinaryOperatorClass:
1256 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
1257 case Expr::CompoundAssignOperatorClass: {
1258 QualType Ty = E->getType();
1259 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1260 Ty = AT->getValueType();
1261 if (!Ty->isAnyComplexType())
1262 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1263 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1265 case Expr::CallExprClass:
1266 case Expr::CXXMemberCallExprClass:
1267 case Expr::CXXOperatorCallExprClass:
1268 case Expr::UserDefinedLiteralClass:
1269 return EmitCallExprLValue(cast<CallExpr>(E));
1270 case Expr::CXXRewrittenBinaryOperatorClass:
1271 return EmitLValue(cast<CXXRewrittenBinaryOperator>(E)->getSemanticForm());
1272 case Expr::VAArgExprClass:
1273 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
1274 case Expr::DeclRefExprClass:
1275 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
1276 case Expr::ConstantExprClass:
1277 return EmitLValue(cast<ConstantExpr>(E)->getSubExpr());
1278 case Expr::ParenExprClass:
1279 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
1280 case Expr::GenericSelectionExprClass:
1281 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
1282 case Expr::PredefinedExprClass:
1283 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
1284 case Expr::StringLiteralClass:
1285 return EmitStringLiteralLValue(cast<StringLiteral>(E));
1286 case Expr::ObjCEncodeExprClass:
1287 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
1288 case Expr::PseudoObjectExprClass:
1289 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
1290 case Expr::InitListExprClass:
1291 return EmitInitListLValue(cast<InitListExpr>(E));
1292 case Expr::CXXTemporaryObjectExprClass:
1293 case Expr::CXXConstructExprClass:
1294 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
1295 case Expr::CXXBindTemporaryExprClass:
1296 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
1297 case Expr::CXXUuidofExprClass:
1298 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
1299 case Expr::LambdaExprClass:
1300 return EmitAggExprToLValue(E);
1302 case Expr::ExprWithCleanupsClass: {
1303 const auto *cleanups = cast<ExprWithCleanups>(E);
1304 enterFullExpression(cleanups);
1305 RunCleanupsScope Scope(*this);
1306 LValue LV = EmitLValue(cleanups->getSubExpr());
1307 if (LV.isSimple()) {
1308 // Defend against branches out of gnu statement expressions surrounded by
1310 llvm::Value *V = LV.getPointer();
1311 Scope.ForceCleanup({&V});
1312 return LValue::MakeAddr(Address(V, LV.getAlignment()), LV.getType(),
1313 getContext(), LV.getBaseInfo(), LV.getTBAAInfo());
1315 // FIXME: Is it possible to create an ExprWithCleanups that produces a
1316 // bitfield lvalue or some other non-simple lvalue?
1320 case Expr::CXXDefaultArgExprClass: {
1321 auto *DAE = cast<CXXDefaultArgExpr>(E);
1322 CXXDefaultArgExprScope Scope(*this, DAE);
1323 return EmitLValue(DAE->getExpr());
1325 case Expr::CXXDefaultInitExprClass: {
1326 auto *DIE = cast<CXXDefaultInitExpr>(E);
1327 CXXDefaultInitExprScope Scope(*this, DIE);
1328 return EmitLValue(DIE->getExpr());
1330 case Expr::CXXTypeidExprClass:
1331 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
1333 case Expr::ObjCMessageExprClass:
1334 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
1335 case Expr::ObjCIvarRefExprClass:
1336 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
1337 case Expr::StmtExprClass:
1338 return EmitStmtExprLValue(cast<StmtExpr>(E));
1339 case Expr::UnaryOperatorClass:
1340 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
1341 case Expr::ArraySubscriptExprClass:
1342 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
1343 case Expr::OMPArraySectionExprClass:
1344 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E));
1345 case Expr::ExtVectorElementExprClass:
1346 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
1347 case Expr::MemberExprClass:
1348 return EmitMemberExpr(cast<MemberExpr>(E));
1349 case Expr::CompoundLiteralExprClass:
1350 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
1351 case Expr::ConditionalOperatorClass:
1352 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
1353 case Expr::BinaryConditionalOperatorClass:
1354 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
1355 case Expr::ChooseExprClass:
1356 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
1357 case Expr::OpaqueValueExprClass:
1358 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
1359 case Expr::SubstNonTypeTemplateParmExprClass:
1360 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
1361 case Expr::ImplicitCastExprClass:
1362 case Expr::CStyleCastExprClass:
1363 case Expr::CXXFunctionalCastExprClass:
1364 case Expr::CXXStaticCastExprClass:
1365 case Expr::CXXDynamicCastExprClass:
1366 case Expr::CXXReinterpretCastExprClass:
1367 case Expr::CXXConstCastExprClass:
1368 case Expr::ObjCBridgedCastExprClass:
1369 return EmitCastLValue(cast<CastExpr>(E));
1371 case Expr::MaterializeTemporaryExprClass:
1372 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
1374 case Expr::CoawaitExprClass:
1375 return EmitCoawaitLValue(cast<CoawaitExpr>(E));
1376 case Expr::CoyieldExprClass:
1377 return EmitCoyieldLValue(cast<CoyieldExpr>(E));
1381 /// Given an object of the given canonical type, can we safely copy a
1382 /// value out of it based on its initializer?
1383 static bool isConstantEmittableObjectType(QualType type) {
1384 assert(type.isCanonical());
1385 assert(!type->isReferenceType());
1387 // Must be const-qualified but non-volatile.
1388 Qualifiers qs = type.getLocalQualifiers();
1389 if (!qs.hasConst() || qs.hasVolatile()) return false;
1391 // Otherwise, all object types satisfy this except C++ classes with
1392 // mutable subobjects or non-trivial copy/destroy behavior.
1393 if (const auto *RT = dyn_cast<RecordType>(type))
1394 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1395 if (RD->hasMutableFields() || !RD->isTrivial())
1401 /// Can we constant-emit a load of a reference to a variable of the
1402 /// given type? This is different from predicates like
1403 /// Decl::mightBeUsableInConstantExpressions because we do want it to apply
1404 /// in situations that don't necessarily satisfy the language's rules
1405 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
1406 /// to do this with const float variables even if those variables
1407 /// aren't marked 'constexpr'.
1408 enum ConstantEmissionKind {
1410 CEK_AsReferenceOnly,
1411 CEK_AsValueOrReference,
1414 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
1415 type = type.getCanonicalType();
1416 if (const auto *ref = dyn_cast<ReferenceType>(type)) {
1417 if (isConstantEmittableObjectType(ref->getPointeeType()))
1418 return CEK_AsValueOrReference;
1419 return CEK_AsReferenceOnly;
1421 if (isConstantEmittableObjectType(type))
1422 return CEK_AsValueOnly;
1426 /// Try to emit a reference to the given value without producing it as
1427 /// an l-value. This is just an optimization, but it avoids us needing
1428 /// to emit global copies of variables if they're named without triggering
1429 /// a formal use in a context where we can't emit a direct reference to them,
1430 /// for instance if a block or lambda or a member of a local class uses a
1431 /// const int variable or constexpr variable from an enclosing function.
1432 CodeGenFunction::ConstantEmission
1433 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
1434 ValueDecl *value = refExpr->getDecl();
1436 // The value needs to be an enum constant or a constant variable.
1437 ConstantEmissionKind CEK;
1438 if (isa<ParmVarDecl>(value)) {
1440 } else if (auto *var = dyn_cast<VarDecl>(value)) {
1441 CEK = checkVarTypeForConstantEmission(var->getType());
1442 } else if (isa<EnumConstantDecl>(value)) {
1443 CEK = CEK_AsValueOnly;
1447 if (CEK == CEK_None) return ConstantEmission();
1449 Expr::EvalResult result;
1450 bool resultIsReference;
1451 QualType resultType;
1453 // It's best to evaluate all the way as an r-value if that's permitted.
1454 if (CEK != CEK_AsReferenceOnly &&
1455 refExpr->EvaluateAsRValue(result, getContext())) {
1456 resultIsReference = false;
1457 resultType = refExpr->getType();
1459 // Otherwise, try to evaluate as an l-value.
1460 } else if (CEK != CEK_AsValueOnly &&
1461 refExpr->EvaluateAsLValue(result, getContext())) {
1462 resultIsReference = true;
1463 resultType = value->getType();
1467 return ConstantEmission();
1470 // In any case, if the initializer has side-effects, abandon ship.
1471 if (result.HasSideEffects)
1472 return ConstantEmission();
1474 // Emit as a constant.
1475 auto C = ConstantEmitter(*this).emitAbstract(refExpr->getLocation(),
1476 result.Val, resultType);
1478 // Make sure we emit a debug reference to the global variable.
1479 // This should probably fire even for
1480 if (isa<VarDecl>(value)) {
1481 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
1482 EmitDeclRefExprDbgValue(refExpr, result.Val);
1484 assert(isa<EnumConstantDecl>(value));
1485 EmitDeclRefExprDbgValue(refExpr, result.Val);
1488 // If we emitted a reference constant, we need to dereference that.
1489 if (resultIsReference)
1490 return ConstantEmission::forReference(C);
1492 return ConstantEmission::forValue(C);
1495 static DeclRefExpr *tryToConvertMemberExprToDeclRefExpr(CodeGenFunction &CGF,
1496 const MemberExpr *ME) {
1497 if (auto *VD = dyn_cast<VarDecl>(ME->getMemberDecl())) {
1498 // Try to emit static variable member expressions as DREs.
1499 return DeclRefExpr::Create(
1500 CGF.getContext(), NestedNameSpecifierLoc(), SourceLocation(), VD,
1501 /*RefersToEnclosingVariableOrCapture=*/false, ME->getExprLoc(),
1502 ME->getType(), ME->getValueKind(), nullptr, nullptr, ME->isNonOdrUse());
1507 CodeGenFunction::ConstantEmission
1508 CodeGenFunction::tryEmitAsConstant(const MemberExpr *ME) {
1509 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, ME))
1510 return tryEmitAsConstant(DRE);
1511 return ConstantEmission();
1514 llvm::Value *CodeGenFunction::emitScalarConstant(
1515 const CodeGenFunction::ConstantEmission &Constant, Expr *E) {
1516 assert(Constant && "not a constant");
1517 if (Constant.isReference())
1518 return EmitLoadOfLValue(Constant.getReferenceLValue(*this, E),
1521 return Constant.getValue();
1524 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1525 SourceLocation Loc) {
1526 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
1527 lvalue.getType(), Loc, lvalue.getBaseInfo(),
1528 lvalue.getTBAAInfo(), lvalue.isNontemporal());
1531 static bool hasBooleanRepresentation(QualType Ty) {
1532 if (Ty->isBooleanType())
1535 if (const EnumType *ET = Ty->getAs<EnumType>())
1536 return ET->getDecl()->getIntegerType()->isBooleanType();
1538 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1539 return hasBooleanRepresentation(AT->getValueType());
1544 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1545 llvm::APInt &Min, llvm::APInt &End,
1546 bool StrictEnums, bool IsBool) {
1547 const EnumType *ET = Ty->getAs<EnumType>();
1548 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1549 ET && !ET->getDecl()->isFixed();
1550 if (!IsBool && !IsRegularCPlusPlusEnum)
1554 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1555 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1557 const EnumDecl *ED = ET->getDecl();
1558 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1559 unsigned Bitwidth = LTy->getScalarSizeInBits();
1560 unsigned NumNegativeBits = ED->getNumNegativeBits();
1561 unsigned NumPositiveBits = ED->getNumPositiveBits();
1563 if (NumNegativeBits) {
1564 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1565 assert(NumBits <= Bitwidth);
1566 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1569 assert(NumPositiveBits <= Bitwidth);
1570 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1571 Min = llvm::APInt(Bitwidth, 0);
1577 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1578 llvm::APInt Min, End;
1579 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums,
1580 hasBooleanRepresentation(Ty)))
1583 llvm::MDBuilder MDHelper(getLLVMContext());
1584 return MDHelper.createRange(Min, End);
1587 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
1588 SourceLocation Loc) {
1589 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool);
1590 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum);
1591 if (!HasBoolCheck && !HasEnumCheck)
1594 bool IsBool = hasBooleanRepresentation(Ty) ||
1595 NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
1596 bool NeedsBoolCheck = HasBoolCheck && IsBool;
1597 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>();
1598 if (!NeedsBoolCheck && !NeedsEnumCheck)
1601 // Single-bit booleans don't need to be checked. Special-case this to avoid
1602 // a bit width mismatch when handling bitfield values. This is handled by
1603 // EmitFromMemory for the non-bitfield case.
1605 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1)
1608 llvm::APInt Min, End;
1609 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool))
1612 auto &Ctx = getLLVMContext();
1613 SanitizerScope SanScope(this);
1617 Check = Builder.CreateICmpULE(Value, llvm::ConstantInt::get(Ctx, End));
1619 llvm::Value *Upper =
1620 Builder.CreateICmpSLE(Value, llvm::ConstantInt::get(Ctx, End));
1621 llvm::Value *Lower =
1622 Builder.CreateICmpSGE(Value, llvm::ConstantInt::get(Ctx, Min));
1623 Check = Builder.CreateAnd(Upper, Lower);
1625 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc),
1626 EmitCheckTypeDescriptor(Ty)};
1627 SanitizerMask Kind =
1628 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
1629 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue,
1630 StaticArgs, EmitCheckValue(Value));
1634 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
1637 LValueBaseInfo BaseInfo,
1638 TBAAAccessInfo TBAAInfo,
1639 bool isNontemporal) {
1640 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1641 // For better performance, handle vector loads differently.
1642 if (Ty->isVectorType()) {
1643 const llvm::Type *EltTy = Addr.getElementType();
1645 const auto *VTy = cast<llvm::VectorType>(EltTy);
1647 // Handle vectors of size 3 like size 4 for better performance.
1648 if (VTy->getNumElements() == 3) {
1650 // Bitcast to vec4 type.
1651 llvm::VectorType *vec4Ty =
1652 llvm::VectorType::get(VTy->getElementType(), 4);
1653 Address Cast = Builder.CreateElementBitCast(Addr, vec4Ty, "castToVec4");
1655 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1657 // Shuffle vector to get vec3.
1658 V = Builder.CreateShuffleVector(V, llvm::UndefValue::get(vec4Ty),
1659 {0, 1, 2}, "extractVec");
1660 return EmitFromMemory(V, Ty);
1665 // Atomic operations have to be done on integral types.
1666 LValue AtomicLValue =
1667 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1668 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) {
1669 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal();
1672 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
1673 if (isNontemporal) {
1674 llvm::MDNode *Node = llvm::MDNode::get(
1675 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1676 Load->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1679 CGM.DecorateInstructionWithTBAA(Load, TBAAInfo);
1681 if (EmitScalarRangeCheck(Load, Ty, Loc)) {
1682 // In order to prevent the optimizer from throwing away the check, don't
1683 // attach range metadata to the load.
1684 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1685 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1686 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1688 return EmitFromMemory(Load, Ty);
1691 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1692 // Bool has a different representation in memory than in registers.
1693 if (hasBooleanRepresentation(Ty)) {
1694 // This should really always be an i1, but sometimes it's already
1695 // an i8, and it's awkward to track those cases down.
1696 if (Value->getType()->isIntegerTy(1))
1697 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1698 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1699 "wrong value rep of bool");
1705 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1706 // Bool has a different representation in memory than in registers.
1707 if (hasBooleanRepresentation(Ty)) {
1708 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1709 "wrong value rep of bool");
1710 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1716 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
1717 bool Volatile, QualType Ty,
1718 LValueBaseInfo BaseInfo,
1719 TBAAAccessInfo TBAAInfo,
1720 bool isInit, bool isNontemporal) {
1721 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1722 // Handle vectors differently to get better performance.
1723 if (Ty->isVectorType()) {
1724 llvm::Type *SrcTy = Value->getType();
1725 auto *VecTy = dyn_cast<llvm::VectorType>(SrcTy);
1726 // Handle vec3 special.
1727 if (VecTy && VecTy->getNumElements() == 3) {
1728 // Our source is a vec3, do a shuffle vector to make it a vec4.
1729 llvm::Constant *Mask[] = {Builder.getInt32(0), Builder.getInt32(1),
1730 Builder.getInt32(2),
1731 llvm::UndefValue::get(Builder.getInt32Ty())};
1732 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1733 Value = Builder.CreateShuffleVector(Value, llvm::UndefValue::get(VecTy),
1734 MaskV, "extractVec");
1735 SrcTy = llvm::VectorType::get(VecTy->getElementType(), 4);
1737 if (Addr.getElementType() != SrcTy) {
1738 Addr = Builder.CreateElementBitCast(Addr, SrcTy, "storetmp");
1743 Value = EmitToMemory(Value, Ty);
1745 LValue AtomicLValue =
1746 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1747 if (Ty->isAtomicType() ||
1748 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) {
1749 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit);
1753 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1754 if (isNontemporal) {
1755 llvm::MDNode *Node =
1756 llvm::MDNode::get(Store->getContext(),
1757 llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1758 Store->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1761 CGM.DecorateInstructionWithTBAA(Store, TBAAInfo);
1764 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1766 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
1767 lvalue.getType(), lvalue.getBaseInfo(),
1768 lvalue.getTBAAInfo(), isInit, lvalue.isNontemporal());
1771 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1772 /// method emits the address of the lvalue, then loads the result as an rvalue,
1773 /// returning the rvalue.
1774 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1775 if (LV.isObjCWeak()) {
1776 // load of a __weak object.
1777 Address AddrWeakObj = LV.getAddress();
1778 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1781 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1782 // In MRC mode, we do a load+autorelease.
1783 if (!getLangOpts().ObjCAutoRefCount) {
1784 return RValue::get(EmitARCLoadWeak(LV.getAddress()));
1787 // In ARC mode, we load retained and then consume the value.
1788 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
1789 Object = EmitObjCConsumeObject(LV.getType(), Object);
1790 return RValue::get(Object);
1793 if (LV.isSimple()) {
1794 assert(!LV.getType()->isFunctionType());
1796 // Everything needs a load.
1797 return RValue::get(EmitLoadOfScalar(LV, Loc));
1800 if (LV.isVectorElt()) {
1801 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(),
1802 LV.isVolatileQualified());
1803 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1807 // If this is a reference to a subset of the elements of a vector, either
1808 // shuffle the input or extract/insert them as appropriate.
1809 if (LV.isExtVectorElt())
1810 return EmitLoadOfExtVectorElementLValue(LV);
1812 // Global Register variables always invoke intrinsics
1813 if (LV.isGlobalReg())
1814 return EmitLoadOfGlobalRegLValue(LV);
1816 assert(LV.isBitField() && "Unknown LValue type!");
1817 return EmitLoadOfBitfieldLValue(LV, Loc);
1820 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
1821 SourceLocation Loc) {
1822 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1824 // Get the output type.
1825 llvm::Type *ResLTy = ConvertType(LV.getType());
1827 Address Ptr = LV.getBitFieldAddress();
1828 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load");
1830 if (Info.IsSigned) {
1831 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1832 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1834 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1835 if (Info.Offset + HighBits)
1836 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1839 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1840 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1841 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1845 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1846 EmitScalarRangeCheck(Val, LV.getType(), Loc);
1847 return RValue::get(Val);
1850 // If this is a reference to a subset of the elements of a vector, create an
1851 // appropriate shufflevector.
1852 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1853 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(),
1854 LV.isVolatileQualified());
1856 const llvm::Constant *Elts = LV.getExtVectorElts();
1858 // If the result of the expression is a non-vector type, we must be extracting
1859 // a single element. Just codegen as an extractelement.
1860 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1862 unsigned InIdx = getAccessedFieldNo(0, Elts);
1863 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1864 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1867 // Always use shuffle vector to try to retain the original program structure
1868 unsigned NumResultElts = ExprVT->getNumElements();
1870 SmallVector<llvm::Constant*, 4> Mask;
1871 for (unsigned i = 0; i != NumResultElts; ++i)
1872 Mask.push_back(Builder.getInt32(getAccessedFieldNo(i, Elts)));
1874 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1875 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1877 return RValue::get(Vec);
1880 /// Generates lvalue for partial ext_vector access.
1881 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) {
1882 Address VectorAddress = LV.getExtVectorAddress();
1883 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1884 QualType EQT = ExprVT->getElementType();
1885 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT);
1887 Address CastToPointerElement =
1888 Builder.CreateElementBitCast(VectorAddress, VectorElementTy,
1889 "conv.ptr.element");
1891 const llvm::Constant *Elts = LV.getExtVectorElts();
1892 unsigned ix = getAccessedFieldNo(0, Elts);
1894 Address VectorBasePtrPlusIx =
1895 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix,
1898 return VectorBasePtrPlusIx;
1901 /// Load of global gamed gegisters are always calls to intrinsics.
1902 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
1903 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
1904 "Bad type for register variable");
1905 llvm::MDNode *RegName = cast<llvm::MDNode>(
1906 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata());
1908 // We accept integer and pointer types only
1909 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
1910 llvm::Type *Ty = OrigTy;
1911 if (OrigTy->isPointerTy())
1912 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1913 llvm::Type *Types[] = { Ty };
1915 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
1916 llvm::Value *Call = Builder.CreateCall(
1917 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName));
1918 if (OrigTy->isPointerTy())
1919 Call = Builder.CreateIntToPtr(Call, OrigTy);
1920 return RValue::get(Call);
1924 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
1925 /// lvalue, where both are guaranteed to the have the same type, and that type
1927 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
1929 if (!Dst.isSimple()) {
1930 if (Dst.isVectorElt()) {
1931 // Read/modify/write the vector, inserting the new element.
1932 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(),
1933 Dst.isVolatileQualified());
1934 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
1935 Dst.getVectorIdx(), "vecins");
1936 Builder.CreateStore(Vec, Dst.getVectorAddress(),
1937 Dst.isVolatileQualified());
1941 // If this is an update of extended vector elements, insert them as
1943 if (Dst.isExtVectorElt())
1944 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
1946 if (Dst.isGlobalReg())
1947 return EmitStoreThroughGlobalRegLValue(Src, Dst);
1949 assert(Dst.isBitField() && "Unknown LValue type");
1950 return EmitStoreThroughBitfieldLValue(Src, Dst);
1953 // There's special magic for assigning into an ARC-qualified l-value.
1954 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
1956 case Qualifiers::OCL_None:
1957 llvm_unreachable("present but none");
1959 case Qualifiers::OCL_ExplicitNone:
1963 case Qualifiers::OCL_Strong:
1965 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal()));
1968 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
1971 case Qualifiers::OCL_Weak:
1973 // Initialize and then skip the primitive store.
1974 EmitARCInitWeak(Dst.getAddress(), Src.getScalarVal());
1976 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true);
1979 case Qualifiers::OCL_Autoreleasing:
1980 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
1981 Src.getScalarVal()));
1982 // fall into the normal path
1987 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
1988 // load of a __weak object.
1989 Address LvalueDst = Dst.getAddress();
1990 llvm::Value *src = Src.getScalarVal();
1991 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
1995 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
1996 // load of a __strong object.
1997 Address LvalueDst = Dst.getAddress();
1998 llvm::Value *src = Src.getScalarVal();
1999 if (Dst.isObjCIvar()) {
2000 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
2001 llvm::Type *ResultType = IntPtrTy;
2002 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp());
2003 llvm::Value *RHS = dst.getPointer();
2004 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
2006 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType,
2007 "sub.ptr.lhs.cast");
2008 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
2009 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
2011 } else if (Dst.isGlobalObjCRef()) {
2012 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
2013 Dst.isThreadLocalRef());
2016 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
2020 assert(Src.isScalar() && "Can't emit an agg store with this method");
2021 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
2024 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
2025 llvm::Value **Result) {
2026 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
2027 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
2028 Address Ptr = Dst.getBitFieldAddress();
2030 // Get the source value, truncated to the width of the bit-field.
2031 llvm::Value *SrcVal = Src.getScalarVal();
2033 // Cast the source to the storage type and shift it into place.
2034 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(),
2035 /*isSigned=*/false);
2036 llvm::Value *MaskedVal = SrcVal;
2038 // See if there are other bits in the bitfield's storage we'll need to load
2039 // and mask together with source before storing.
2040 if (Info.StorageSize != Info.Size) {
2041 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
2043 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load");
2045 // Mask the source value as needed.
2046 if (!hasBooleanRepresentation(Dst.getType()))
2047 SrcVal = Builder.CreateAnd(SrcVal,
2048 llvm::APInt::getLowBitsSet(Info.StorageSize,
2053 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
2055 // Mask out the original value.
2056 Val = Builder.CreateAnd(Val,
2057 ~llvm::APInt::getBitsSet(Info.StorageSize,
2059 Info.Offset + Info.Size),
2062 // Or together the unchanged values and the source value.
2063 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
2065 assert(Info.Offset == 0);
2068 // Write the new value back out.
2069 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified());
2071 // Return the new value of the bit-field, if requested.
2073 llvm::Value *ResultVal = MaskedVal;
2075 // Sign extend the value if needed.
2076 if (Info.IsSigned) {
2077 assert(Info.Size <= Info.StorageSize);
2078 unsigned HighBits = Info.StorageSize - Info.Size;
2080 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
2081 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
2085 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
2087 *Result = EmitFromMemory(ResultVal, Dst.getType());
2091 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
2093 // This access turns into a read/modify/write of the vector. Load the input
2095 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddress(),
2096 Dst.isVolatileQualified());
2097 const llvm::Constant *Elts = Dst.getExtVectorElts();
2099 llvm::Value *SrcVal = Src.getScalarVal();
2101 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
2102 unsigned NumSrcElts = VTy->getNumElements();
2103 unsigned NumDstElts = Vec->getType()->getVectorNumElements();
2104 if (NumDstElts == NumSrcElts) {
2105 // Use shuffle vector is the src and destination are the same number of
2106 // elements and restore the vector mask since it is on the side it will be
2108 SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
2109 for (unsigned i = 0; i != NumSrcElts; ++i)
2110 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i);
2112 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
2113 Vec = Builder.CreateShuffleVector(SrcVal,
2114 llvm::UndefValue::get(Vec->getType()),
2116 } else if (NumDstElts > NumSrcElts) {
2117 // Extended the source vector to the same length and then shuffle it
2118 // into the destination.
2119 // FIXME: since we're shuffling with undef, can we just use the indices
2120 // into that? This could be simpler.
2121 SmallVector<llvm::Constant*, 4> ExtMask;
2122 for (unsigned i = 0; i != NumSrcElts; ++i)
2123 ExtMask.push_back(Builder.getInt32(i));
2124 ExtMask.resize(NumDstElts, llvm::UndefValue::get(Int32Ty));
2125 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
2126 llvm::Value *ExtSrcVal =
2127 Builder.CreateShuffleVector(SrcVal,
2128 llvm::UndefValue::get(SrcVal->getType()),
2131 SmallVector<llvm::Constant*, 4> Mask;
2132 for (unsigned i = 0; i != NumDstElts; ++i)
2133 Mask.push_back(Builder.getInt32(i));
2135 // When the vector size is odd and .odd or .hi is used, the last element
2136 // of the Elts constant array will be one past the size of the vector.
2137 // Ignore the last element here, if it is greater than the mask size.
2138 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
2141 // modify when what gets shuffled in
2142 for (unsigned i = 0; i != NumSrcElts; ++i)
2143 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i+NumDstElts);
2144 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
2145 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV);
2147 // We should never shorten the vector
2148 llvm_unreachable("unexpected shorten vector length");
2151 // If the Src is a scalar (not a vector) it must be updating one element.
2152 unsigned InIdx = getAccessedFieldNo(0, Elts);
2153 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
2154 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
2157 Builder.CreateStore(Vec, Dst.getExtVectorAddress(),
2158 Dst.isVolatileQualified());
2161 /// Store of global named registers are always calls to intrinsics.
2162 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
2163 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
2164 "Bad type for register variable");
2165 llvm::MDNode *RegName = cast<llvm::MDNode>(
2166 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata());
2167 assert(RegName && "Register LValue is not metadata");
2169 // We accept integer and pointer types only
2170 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
2171 llvm::Type *Ty = OrigTy;
2172 if (OrigTy->isPointerTy())
2173 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
2174 llvm::Type *Types[] = { Ty };
2176 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
2177 llvm::Value *Value = Src.getScalarVal();
2178 if (OrigTy->isPointerTy())
2179 Value = Builder.CreatePtrToInt(Value, Ty);
2181 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value});
2184 // setObjCGCLValueClass - sets class of the lvalue for the purpose of
2185 // generating write-barries API. It is currently a global, ivar,
2187 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
2189 bool IsMemberAccess=false) {
2190 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
2193 if (isa<ObjCIvarRefExpr>(E)) {
2194 QualType ExpTy = E->getType();
2195 if (IsMemberAccess && ExpTy->isPointerType()) {
2196 // If ivar is a structure pointer, assigning to field of
2197 // this struct follows gcc's behavior and makes it a non-ivar
2198 // writer-barrier conservatively.
2199 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType();
2200 if (ExpTy->isRecordType()) {
2201 LV.setObjCIvar(false);
2205 LV.setObjCIvar(true);
2206 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
2207 LV.setBaseIvarExp(Exp->getBase());
2208 LV.setObjCArray(E->getType()->isArrayType());
2212 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
2213 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
2214 if (VD->hasGlobalStorage()) {
2215 LV.setGlobalObjCRef(true);
2216 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
2219 LV.setObjCArray(E->getType()->isArrayType());
2223 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
2224 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2228 if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
2229 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2230 if (LV.isObjCIvar()) {
2231 // If cast is to a structure pointer, follow gcc's behavior and make it
2232 // a non-ivar write-barrier.
2233 QualType ExpTy = E->getType();
2234 if (ExpTy->isPointerType())
2235 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType();
2236 if (ExpTy->isRecordType())
2237 LV.setObjCIvar(false);
2242 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
2243 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
2247 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
2248 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2252 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
2253 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2257 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
2258 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2262 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
2263 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
2264 if (LV.isObjCIvar() && !LV.isObjCArray())
2265 // Using array syntax to assigning to what an ivar points to is not
2266 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
2267 LV.setObjCIvar(false);
2268 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
2269 // Using array syntax to assigning to what global points to is not
2270 // same as assigning to the global itself. {id *G;} G[i] = 0;
2271 LV.setGlobalObjCRef(false);
2275 if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
2276 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
2277 // We don't know if member is an 'ivar', but this flag is looked at
2278 // only in the context of LV.isObjCIvar().
2279 LV.setObjCArray(E->getType()->isArrayType());
2284 static llvm::Value *
2285 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
2286 llvm::Value *V, llvm::Type *IRType,
2287 StringRef Name = StringRef()) {
2288 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
2289 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
2292 static LValue EmitThreadPrivateVarDeclLValue(
2293 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr,
2294 llvm::Type *RealVarTy, SourceLocation Loc) {
2295 Addr = CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc);
2296 Addr = CGF.Builder.CreateElementBitCast(Addr, RealVarTy);
2297 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2300 static Address emitDeclTargetVarDeclLValue(CodeGenFunction &CGF,
2301 const VarDecl *VD, QualType T) {
2302 llvm::Optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
2303 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD);
2304 // Return an invalid address if variable is MT_To and unified
2305 // memory is not enabled. For all other cases: MT_Link and
2306 // MT_To with unified memory, return a valid address.
2307 if (!Res || (*Res == OMPDeclareTargetDeclAttr::MT_To &&
2308 !CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory()))
2309 return Address::invalid();
2310 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) ||
2311 (*Res == OMPDeclareTargetDeclAttr::MT_To &&
2312 CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) &&
2313 "Expected link clause OR to clause with unified memory enabled.");
2314 QualType PtrTy = CGF.getContext().getPointerType(VD->getType());
2315 Address Addr = CGF.CGM.getOpenMPRuntime().getAddrOfDeclareTargetVar(VD);
2316 return CGF.EmitLoadOfPointer(Addr, PtrTy->castAs<PointerType>());
2320 CodeGenFunction::EmitLoadOfReference(LValue RefLVal,
2321 LValueBaseInfo *PointeeBaseInfo,
2322 TBAAAccessInfo *PointeeTBAAInfo) {
2323 llvm::LoadInst *Load = Builder.CreateLoad(RefLVal.getAddress(),
2324 RefLVal.isVolatile());
2325 CGM.DecorateInstructionWithTBAA(Load, RefLVal.getTBAAInfo());
2327 CharUnits Align = getNaturalTypeAlignment(RefLVal.getType()->getPointeeType(),
2328 PointeeBaseInfo, PointeeTBAAInfo,
2329 /* forPointeeType= */ true);
2330 return Address(Load, Align);
2333 LValue CodeGenFunction::EmitLoadOfReferenceLValue(LValue RefLVal) {
2334 LValueBaseInfo PointeeBaseInfo;
2335 TBAAAccessInfo PointeeTBAAInfo;
2336 Address PointeeAddr = EmitLoadOfReference(RefLVal, &PointeeBaseInfo,
2338 return MakeAddrLValue(PointeeAddr, RefLVal.getType()->getPointeeType(),
2339 PointeeBaseInfo, PointeeTBAAInfo);
2342 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr,
2343 const PointerType *PtrTy,
2344 LValueBaseInfo *BaseInfo,
2345 TBAAAccessInfo *TBAAInfo) {
2346 llvm::Value *Addr = Builder.CreateLoad(Ptr);
2347 return Address(Addr, getNaturalTypeAlignment(PtrTy->getPointeeType(),
2349 /*forPointeeType=*/true));
2352 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr,
2353 const PointerType *PtrTy) {
2354 LValueBaseInfo BaseInfo;
2355 TBAAAccessInfo TBAAInfo;
2356 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo, &TBAAInfo);
2357 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo, TBAAInfo);
2360 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
2361 const Expr *E, const VarDecl *VD) {
2362 QualType T = E->getType();
2364 // If it's thread_local, emit a call to its wrapper function instead.
2365 if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
2366 CGF.CGM.getCXXABI().usesThreadWrapperFunction(VD))
2367 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
2368 // Check if the variable is marked as declare target with link clause in
2370 if (CGF.getLangOpts().OpenMPIsDevice) {
2371 Address Addr = emitDeclTargetVarDeclLValue(CGF, VD, T);
2373 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2376 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
2377 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
2378 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
2379 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
2380 Address Addr(V, Alignment);
2381 // Emit reference to the private copy of the variable if it is an OpenMP
2382 // threadprivate variable.
2383 if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd &&
2384 VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2385 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
2388 LValue LV = VD->getType()->isReferenceType() ?
2389 CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(),
2390 AlignmentSource::Decl) :
2391 CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2392 setObjCGCLValueClass(CGF.getContext(), E, LV);
2396 static llvm::Constant *EmitFunctionDeclPointer(CodeGenModule &CGM,
2397 const FunctionDecl *FD) {
2398 if (FD->hasAttr<WeakRefAttr>()) {
2399 ConstantAddress aliasee = CGM.GetWeakRefReference(FD);
2400 return aliasee.getPointer();
2403 llvm::Constant *V = CGM.GetAddrOfFunction(FD);
2404 if (!FD->hasPrototype()) {
2405 if (const FunctionProtoType *Proto =
2406 FD->getType()->getAs<FunctionProtoType>()) {
2407 // Ugly case: for a K&R-style definition, the type of the definition
2408 // isn't the same as the type of a use. Correct for this with a
2410 QualType NoProtoType =
2411 CGM.getContext().getFunctionNoProtoType(Proto->getReturnType());
2412 NoProtoType = CGM.getContext().getPointerType(NoProtoType);
2413 V = llvm::ConstantExpr::getBitCast(V,
2414 CGM.getTypes().ConvertType(NoProtoType));
2420 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
2421 const Expr *E, const FunctionDecl *FD) {
2422 llvm::Value *V = EmitFunctionDeclPointer(CGF.CGM, FD);
2423 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
2424 return CGF.MakeAddrLValue(V, E->getType(), Alignment,
2425 AlignmentSource::Decl);
2428 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
2429 llvm::Value *ThisValue) {
2430 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
2431 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
2432 return CGF.EmitLValueForField(LV, FD);
2435 /// Named Registers are named metadata pointing to the register name
2436 /// which will be read from/written to as an argument to the intrinsic
2437 /// @llvm.read/write_register.
2438 /// So far, only the name is being passed down, but other options such as
2439 /// register type, allocation type or even optimization options could be
2440 /// passed down via the metadata node.
2441 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) {
2442 SmallString<64> Name("llvm.named.register.");
2443 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
2444 assert(Asm->getLabel().size() < 64-Name.size() &&
2445 "Register name too big");
2446 Name.append(Asm->getLabel());
2447 llvm::NamedMDNode *M =
2448 CGM.getModule().getOrInsertNamedMetadata(Name);
2449 if (M->getNumOperands() == 0) {
2450 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
2452 llvm::Metadata *Ops[] = {Str};
2453 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
2456 CharUnits Alignment = CGM.getContext().getDeclAlign(VD);
2459 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0));
2460 return LValue::MakeGlobalReg(Address(Ptr, Alignment), VD->getType());
2463 /// Determine whether we can emit a reference to \p VD from the current
2464 /// context, despite not necessarily having seen an odr-use of the variable in
2466 static bool canEmitSpuriousReferenceToVariable(CodeGenFunction &CGF,
2467 const DeclRefExpr *E,
2470 // For a variable declared in an enclosing scope, do not emit a spurious
2471 // reference even if we have a capture, as that will emit an unwarranted
2472 // reference to our capture state, and will likely generate worse code than
2473 // emitting a local copy.
2474 if (E->refersToEnclosingVariableOrCapture())
2477 // For a local declaration declared in this function, we can always reference
2478 // it even if we don't have an odr-use.
2479 if (VD->hasLocalStorage()) {
2480 return VD->getDeclContext() ==
2481 dyn_cast_or_null<DeclContext>(CGF.CurCodeDecl);
2484 // For a global declaration, we can emit a reference to it if we know
2485 // for sure that we are able to emit a definition of it.
2486 VD = VD->getDefinition(CGF.getContext());
2490 // Don't emit a spurious reference if it might be to a variable that only
2491 // exists on a different device / target.
2492 // FIXME: This is unnecessarily broad. Check whether this would actually be a
2493 // cross-target reference.
2494 if (CGF.getLangOpts().OpenMP || CGF.getLangOpts().CUDA ||
2495 CGF.getLangOpts().OpenCL) {
2499 // We can emit a spurious reference only if the linkage implies that we'll
2500 // be emitting a non-interposable symbol that will be retained until link
2502 switch (CGF.CGM.getLLVMLinkageVarDefinition(VD, IsConstant)) {
2503 case llvm::GlobalValue::ExternalLinkage:
2504 case llvm::GlobalValue::LinkOnceODRLinkage:
2505 case llvm::GlobalValue::WeakODRLinkage:
2506 case llvm::GlobalValue::InternalLinkage:
2507 case llvm::GlobalValue::PrivateLinkage:
2514 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
2515 const NamedDecl *ND = E->getDecl();
2516 QualType T = E->getType();
2518 assert(E->isNonOdrUse() != NOUR_Unevaluated &&
2519 "should not emit an unevaluated operand");
2521 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2522 // Global Named registers access via intrinsics only
2523 if (VD->getStorageClass() == SC_Register &&
2524 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
2525 return EmitGlobalNamedRegister(VD, CGM);
2527 // If this DeclRefExpr does not constitute an odr-use of the variable,
2528 // we're not permitted to emit a reference to it in general, and it might
2529 // not be captured if capture would be necessary for a use. Emit the
2530 // constant value directly instead.
2531 if (E->isNonOdrUse() == NOUR_Constant &&
2532 (VD->getType()->isReferenceType() ||
2533 !canEmitSpuriousReferenceToVariable(*this, E, VD, true))) {
2534 VD->getAnyInitializer(VD);
2535 llvm::Constant *Val = ConstantEmitter(*this).emitAbstract(
2536 E->getLocation(), *VD->evaluateValue(), VD->getType());
2537 assert(Val && "failed to emit constant expression");
2539 Address Addr = Address::invalid();
2540 if (!VD->getType()->isReferenceType()) {
2541 // Spill the constant value to a global.
2542 Addr = CGM.createUnnamedGlobalFrom(*VD, Val,
2543 getContext().getDeclAlign(VD));
2544 llvm::Type *VarTy = getTypes().ConvertTypeForMem(VD->getType());
2545 auto *PTy = llvm::PointerType::get(
2546 VarTy, getContext().getTargetAddressSpace(VD->getType()));
2547 if (PTy != Addr.getType())
2548 Addr = Builder.CreatePointerBitCastOrAddrSpaceCast(Addr, PTy);
2550 // Should we be using the alignment of the constant pointer we emitted?
2551 CharUnits Alignment =
2552 getNaturalTypeAlignment(E->getType(),
2553 /* BaseInfo= */ nullptr,
2554 /* TBAAInfo= */ nullptr,
2555 /* forPointeeType= */ true);
2556 Addr = Address(Val, Alignment);
2558 return MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2561 // FIXME: Handle other kinds of non-odr-use DeclRefExprs.
2563 // Check for captured variables.
2564 if (E->refersToEnclosingVariableOrCapture()) {
2565 VD = VD->getCanonicalDecl();
2566 if (auto *FD = LambdaCaptureFields.lookup(VD))
2567 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
2568 else if (CapturedStmtInfo) {
2569 auto I = LocalDeclMap.find(VD);
2570 if (I != LocalDeclMap.end()) {
2571 if (VD->getType()->isReferenceType())
2572 return EmitLoadOfReferenceLValue(I->second, VD->getType(),
2573 AlignmentSource::Decl);
2574 return MakeAddrLValue(I->second, T);
2577 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD),
2578 CapturedStmtInfo->getContextValue());
2579 return MakeAddrLValue(
2580 Address(CapLVal.getPointer(), getContext().getDeclAlign(VD)),
2581 CapLVal.getType(), LValueBaseInfo(AlignmentSource::Decl),
2582 CapLVal.getTBAAInfo());
2585 assert(isa<BlockDecl>(CurCodeDecl));
2586 Address addr = GetAddrOfBlockDecl(VD);
2587 return MakeAddrLValue(addr, T, AlignmentSource::Decl);
2591 // FIXME: We should be able to assert this for FunctionDecls as well!
2592 // FIXME: We should be able to assert this for all DeclRefExprs, not just
2593 // those with a valid source location.
2594 assert((ND->isUsed(false) || !isa<VarDecl>(ND) || E->isNonOdrUse() ||
2595 !E->getLocation().isValid()) &&
2596 "Should not use decl without marking it used!");
2598 if (ND->hasAttr<WeakRefAttr>()) {
2599 const auto *VD = cast<ValueDecl>(ND);
2600 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD);
2601 return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl);
2604 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2605 // Check if this is a global variable.
2606 if (VD->hasLinkage() || VD->isStaticDataMember())
2607 return EmitGlobalVarDeclLValue(*this, E, VD);
2609 Address addr = Address::invalid();
2611 // The variable should generally be present in the local decl map.
2612 auto iter = LocalDeclMap.find(VD);
2613 if (iter != LocalDeclMap.end()) {
2614 addr = iter->second;
2616 // Otherwise, it might be static local we haven't emitted yet for
2617 // some reason; most likely, because it's in an outer function.
2618 } else if (VD->isStaticLocal()) {
2619 addr = Address(CGM.getOrCreateStaticVarDecl(
2620 *VD, CGM.getLLVMLinkageVarDefinition(VD, /*IsConstant=*/false)),
2621 getContext().getDeclAlign(VD));
2623 // No other cases for now.
2625 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?");
2629 // Check for OpenMP threadprivate variables.
2630 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd &&
2631 VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2632 return EmitThreadPrivateVarDeclLValue(
2633 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
2637 // Drill into block byref variables.
2638 bool isBlockByref = VD->isEscapingByref();
2640 addr = emitBlockByrefAddress(addr, VD);
2643 // Drill into reference types.
2644 LValue LV = VD->getType()->isReferenceType() ?
2645 EmitLoadOfReferenceLValue(addr, VD->getType(), AlignmentSource::Decl) :
2646 MakeAddrLValue(addr, T, AlignmentSource::Decl);
2648 bool isLocalStorage = VD->hasLocalStorage();
2650 bool NonGCable = isLocalStorage &&
2651 !VD->getType()->isReferenceType() &&
2654 LV.getQuals().removeObjCGCAttr();
2658 bool isImpreciseLifetime =
2659 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
2660 if (isImpreciseLifetime)
2661 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
2662 setObjCGCLValueClass(getContext(), E, LV);
2666 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
2667 return EmitFunctionDeclLValue(*this, E, FD);
2669 // FIXME: While we're emitting a binding from an enclosing scope, all other
2670 // DeclRefExprs we see should be implicitly treated as if they also refer to
2671 // an enclosing scope.
2672 if (const auto *BD = dyn_cast<BindingDecl>(ND))
2673 return EmitLValue(BD->getBinding());
2675 llvm_unreachable("Unhandled DeclRefExpr");
2678 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
2679 // __extension__ doesn't affect lvalue-ness.
2680 if (E->getOpcode() == UO_Extension)
2681 return EmitLValue(E->getSubExpr());
2683 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
2684 switch (E->getOpcode()) {
2685 default: llvm_unreachable("Unknown unary operator lvalue!");
2687 QualType T = E->getSubExpr()->getType()->getPointeeType();
2688 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
2690 LValueBaseInfo BaseInfo;
2691 TBAAAccessInfo TBAAInfo;
2692 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo,
2694 LValue LV = MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo);
2695 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
2697 // We should not generate __weak write barrier on indirect reference
2698 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
2699 // But, we continue to generate __strong write barrier on indirect write
2700 // into a pointer to object.
2701 if (getLangOpts().ObjC &&
2702 getLangOpts().getGC() != LangOptions::NonGC &&
2704 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2709 LValue LV = EmitLValue(E->getSubExpr());
2710 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
2712 // __real is valid on scalars. This is a faster way of testing that.
2713 // __imag can only produce an rvalue on scalars.
2714 if (E->getOpcode() == UO_Real &&
2715 !LV.getAddress().getElementType()->isStructTy()) {
2716 assert(E->getSubExpr()->getType()->isArithmeticType());
2720 QualType T = ExprTy->castAs<ComplexType>()->getElementType();
2723 (E->getOpcode() == UO_Real
2724 ? emitAddrOfRealComponent(LV.getAddress(), LV.getType())
2725 : emitAddrOfImagComponent(LV.getAddress(), LV.getType()));
2726 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo(),
2727 CGM.getTBAAInfoForSubobject(LV, T));
2728 ElemLV.getQuals().addQualifiers(LV.getQuals());
2733 LValue LV = EmitLValue(E->getSubExpr());
2734 bool isInc = E->getOpcode() == UO_PreInc;
2736 if (E->getType()->isAnyComplexType())
2737 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
2739 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
2745 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
2746 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
2747 E->getType(), AlignmentSource::Decl);
2750 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
2751 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
2752 E->getType(), AlignmentSource::Decl);
2755 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
2756 auto SL = E->getFunctionName();
2757 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr");
2758 StringRef FnName = CurFn->getName();
2759 if (FnName.startswith("\01"))
2760 FnName = FnName.substr(1);
2761 StringRef NameItems[] = {
2762 PredefinedExpr::getIdentKindName(E->getIdentKind()), FnName};
2763 std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
2764 if (auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl)) {
2765 std::string Name = SL->getString();
2766 if (!Name.empty()) {
2767 unsigned Discriminator =
2768 CGM.getCXXABI().getMangleContext().getBlockId(BD, true);
2770 Name += "_" + Twine(Discriminator + 1).str();
2771 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str());
2772 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2774 auto C = CGM.GetAddrOfConstantCString(FnName, GVName.c_str());
2775 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2778 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
2779 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2782 /// Emit a type description suitable for use by a runtime sanitizer library. The
2783 /// format of a type descriptor is
2786 /// { i16 TypeKind, i16 TypeInfo }
2789 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2790 /// integer, 1 for a floating point value, and -1 for anything else.
2791 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2792 // Only emit each type's descriptor once.
2793 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
2796 uint16_t TypeKind = -1;
2797 uint16_t TypeInfo = 0;
2799 if (T->isIntegerType()) {
2801 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2802 (T->isSignedIntegerType() ? 1 : 0);
2803 } else if (T->isFloatingType()) {
2805 TypeInfo = getContext().getTypeSize(T);
2808 // Format the type name as if for a diagnostic, including quotes and
2809 // optionally an 'aka'.
2810 SmallString<32> Buffer;
2811 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2812 (intptr_t)T.getAsOpaquePtr(),
2813 StringRef(), StringRef(), None, Buffer,
2816 llvm::Constant *Components[] = {
2817 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2818 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2820 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2822 auto *GV = new llvm::GlobalVariable(
2823 CGM.getModule(), Descriptor->getType(),
2824 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
2825 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2826 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV);
2828 // Remember the descriptor for this type.
2829 CGM.setTypeDescriptorInMap(T, GV);
2834 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2835 llvm::Type *TargetTy = IntPtrTy;
2837 if (V->getType() == TargetTy)
2840 // Floating-point types which fit into intptr_t are bitcast to integers
2841 // and then passed directly (after zero-extension, if necessary).
2842 if (V->getType()->isFloatingPointTy()) {
2843 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2844 if (Bits <= TargetTy->getIntegerBitWidth())
2845 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2849 // Integers which fit in intptr_t are zero-extended and passed directly.
2850 if (V->getType()->isIntegerTy() &&
2851 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2852 return Builder.CreateZExt(V, TargetTy);
2854 // Pointers are passed directly, everything else is passed by address.
2855 if (!V->getType()->isPointerTy()) {
2856 Address Ptr = CreateDefaultAlignTempAlloca(V->getType());
2857 Builder.CreateStore(V, Ptr);
2858 V = Ptr.getPointer();
2860 return Builder.CreatePtrToInt(V, TargetTy);
2863 /// Emit a representation of a SourceLocation for passing to a handler
2864 /// in a sanitizer runtime library. The format for this data is:
2866 /// struct SourceLocation {
2867 /// const char *Filename;
2868 /// int32_t Line, Column;
2871 /// For an invalid SourceLocation, the Filename pointer is null.
2872 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
2873 llvm::Constant *Filename;
2876 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
2877 if (PLoc.isValid()) {
2878 StringRef FilenameString = PLoc.getFilename();
2880 int PathComponentsToStrip =
2881 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip;
2882 if (PathComponentsToStrip < 0) {
2883 assert(PathComponentsToStrip != INT_MIN);
2884 int PathComponentsToKeep = -PathComponentsToStrip;
2885 auto I = llvm::sys::path::rbegin(FilenameString);
2886 auto E = llvm::sys::path::rend(FilenameString);
2887 while (I != E && --PathComponentsToKeep)
2890 FilenameString = FilenameString.substr(I - E);
2891 } else if (PathComponentsToStrip > 0) {
2892 auto I = llvm::sys::path::begin(FilenameString);
2893 auto E = llvm::sys::path::end(FilenameString);
2894 while (I != E && PathComponentsToStrip--)
2899 FilenameString.substr(I - llvm::sys::path::begin(FilenameString));
2901 FilenameString = llvm::sys::path::filename(FilenameString);
2904 auto FilenameGV = CGM.GetAddrOfConstantCString(FilenameString, ".src");
2905 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
2906 cast<llvm::GlobalVariable>(FilenameGV.getPointer()));
2907 Filename = FilenameGV.getPointer();
2908 Line = PLoc.getLine();
2909 Column = PLoc.getColumn();
2911 Filename = llvm::Constant::getNullValue(Int8PtrTy);
2915 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
2916 Builder.getInt32(Column)};
2918 return llvm::ConstantStruct::getAnon(Data);
2922 /// Specify under what conditions this check can be recovered
2923 enum class CheckRecoverableKind {
2924 /// Always terminate program execution if this check fails.
2926 /// Check supports recovering, runtime has both fatal (noreturn) and
2927 /// non-fatal handlers for this check.
2929 /// Runtime conditionally aborts, always need to support recovery.
2934 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) {
2935 assert(Kind.countPopulation() == 1);
2936 if (Kind == SanitizerKind::Function || Kind == SanitizerKind::Vptr)
2937 return CheckRecoverableKind::AlwaysRecoverable;
2938 else if (Kind == SanitizerKind::Return || Kind == SanitizerKind::Unreachable)
2939 return CheckRecoverableKind::Unrecoverable;
2941 return CheckRecoverableKind::Recoverable;
2945 struct SanitizerHandlerInfo {
2946 char const *const Name;
2951 const SanitizerHandlerInfo SanitizerHandlers[] = {
2952 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version},
2953 LIST_SANITIZER_CHECKS
2954 #undef SANITIZER_CHECK
2957 static void emitCheckHandlerCall(CodeGenFunction &CGF,
2958 llvm::FunctionType *FnType,
2959 ArrayRef<llvm::Value *> FnArgs,
2960 SanitizerHandler CheckHandler,
2961 CheckRecoverableKind RecoverKind, bool IsFatal,
2962 llvm::BasicBlock *ContBB) {
2963 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable);
2964 Optional<ApplyDebugLocation> DL;
2965 if (!CGF.Builder.getCurrentDebugLocation()) {
2966 // Ensure that the call has at least an artificial debug location.
2967 DL.emplace(CGF, SourceLocation());
2969 bool NeedsAbortSuffix =
2970 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable;
2971 bool MinimalRuntime = CGF.CGM.getCodeGenOpts().SanitizeMinimalRuntime;
2972 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler];
2973 const StringRef CheckName = CheckInfo.Name;
2974 std::string FnName = "__ubsan_handle_" + CheckName.str();
2975 if (CheckInfo.Version && !MinimalRuntime)
2976 FnName += "_v" + llvm::utostr(CheckInfo.Version);
2978 FnName += "_minimal";
2979 if (NeedsAbortSuffix)
2982 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable;
2984 llvm::AttrBuilder B;
2986 B.addAttribute(llvm::Attribute::NoReturn)
2987 .addAttribute(llvm::Attribute::NoUnwind);
2989 B.addAttribute(llvm::Attribute::UWTable);
2991 llvm::FunctionCallee Fn = CGF.CGM.CreateRuntimeFunction(
2993 llvm::AttributeList::get(CGF.getLLVMContext(),
2994 llvm::AttributeList::FunctionIndex, B),
2996 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs);
2998 HandlerCall->setDoesNotReturn();
2999 CGF.Builder.CreateUnreachable();
3001 CGF.Builder.CreateBr(ContBB);
3005 void CodeGenFunction::EmitCheck(
3006 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
3007 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs,
3008 ArrayRef<llvm::Value *> DynamicArgs) {
3009 assert(IsSanitizerScope);
3010 assert(Checked.size() > 0);
3011 assert(CheckHandler >= 0 &&
3012 size_t(CheckHandler) < llvm::array_lengthof(SanitizerHandlers));
3013 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name;
3015 llvm::Value *FatalCond = nullptr;
3016 llvm::Value *RecoverableCond = nullptr;
3017 llvm::Value *TrapCond = nullptr;
3018 for (int i = 0, n = Checked.size(); i < n; ++i) {
3019 llvm::Value *Check = Checked[i].first;
3020 // -fsanitize-trap= overrides -fsanitize-recover=.
3021 llvm::Value *&Cond =
3022 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second)
3024 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second)
3027 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check;
3031 EmitTrapCheck(TrapCond);
3032 if (!FatalCond && !RecoverableCond)
3035 llvm::Value *JointCond;
3036 if (FatalCond && RecoverableCond)
3037 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond);
3039 JointCond = FatalCond ? FatalCond : RecoverableCond;
3042 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second);
3043 assert(SanOpts.has(Checked[0].second));
3045 for (int i = 1, n = Checked.size(); i < n; ++i) {
3046 assert(RecoverKind == getRecoverableKind(Checked[i].second) &&
3047 "All recoverable kinds in a single check must be same!");
3048 assert(SanOpts.has(Checked[i].second));
3052 llvm::BasicBlock *Cont = createBasicBlock("cont");
3053 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName);
3054 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers);
3055 // Give hint that we very much don't expect to execute the handler
3056 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
3057 llvm::MDBuilder MDHelper(getLLVMContext());
3058 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
3059 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
3060 EmitBlock(Handlers);
3062 // Handler functions take an i8* pointing to the (handler-specific) static
3063 // information block, followed by a sequence of intptr_t arguments
3064 // representing operand values.
3065 SmallVector<llvm::Value *, 4> Args;
3066 SmallVector<llvm::Type *, 4> ArgTypes;
3067 if (!CGM.getCodeGenOpts().SanitizeMinimalRuntime) {
3068 Args.reserve(DynamicArgs.size() + 1);
3069 ArgTypes.reserve(DynamicArgs.size() + 1);
3071 // Emit handler arguments and create handler function type.
3072 if (!StaticArgs.empty()) {
3073 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3075 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
3076 llvm::GlobalVariable::PrivateLinkage, Info);
3077 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3078 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3079 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
3080 ArgTypes.push_back(Int8PtrTy);
3083 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
3084 Args.push_back(EmitCheckValue(DynamicArgs[i]));
3085 ArgTypes.push_back(IntPtrTy);
3089 llvm::FunctionType *FnType =
3090 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
3092 if (!FatalCond || !RecoverableCond) {
3093 // Simple case: we need to generate a single handler call, either
3094 // fatal, or non-fatal.
3095 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind,
3096 (FatalCond != nullptr), Cont);
3098 // Emit two handler calls: first one for set of unrecoverable checks,
3099 // another one for recoverable.
3100 llvm::BasicBlock *NonFatalHandlerBB =
3101 createBasicBlock("non_fatal." + CheckName);
3102 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName);
3103 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB);
3104 EmitBlock(FatalHandlerBB);
3105 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true,
3107 EmitBlock(NonFatalHandlerBB);
3108 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false,
3115 void CodeGenFunction::EmitCfiSlowPathCheck(
3116 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId,
3117 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) {
3118 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont");
3120 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath");
3121 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB);
3123 llvm::MDBuilder MDHelper(getLLVMContext());
3124 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
3125 BI->setMetadata(llvm::LLVMContext::MD_prof, Node);
3129 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind);
3131 llvm::CallInst *CheckCall;
3132 llvm::FunctionCallee SlowPathFn;
3134 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3136 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
3137 llvm::GlobalVariable::PrivateLinkage, Info);
3138 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3139 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3141 SlowPathFn = CGM.getModule().getOrInsertFunction(
3142 "__cfi_slowpath_diag",
3143 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy},
3145 CheckCall = Builder.CreateCall(
3146 SlowPathFn, {TypeId, Ptr, Builder.CreateBitCast(InfoPtr, Int8PtrTy)});
3148 SlowPathFn = CGM.getModule().getOrInsertFunction(
3150 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false));
3151 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr});
3155 cast<llvm::GlobalValue>(SlowPathFn.getCallee()->stripPointerCasts()));
3156 CheckCall->setDoesNotThrow();
3161 // Emit a stub for __cfi_check function so that the linker knows about this
3162 // symbol in LTO mode.
3163 void CodeGenFunction::EmitCfiCheckStub() {
3164 llvm::Module *M = &CGM.getModule();
3165 auto &Ctx = M->getContext();
3166 llvm::Function *F = llvm::Function::Create(
3167 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false),
3168 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M);
3170 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F);
3171 // FIXME: consider emitting an intrinsic call like
3172 // call void @llvm.cfi_check(i64 %0, i8* %1, i8* %2)
3173 // which can be lowered in CrossDSOCFI pass to the actual contents of
3174 // __cfi_check. This would allow inlining of __cfi_check calls.
3175 llvm::CallInst::Create(
3176 llvm::Intrinsic::getDeclaration(M, llvm::Intrinsic::trap), "", BB);
3177 llvm::ReturnInst::Create(Ctx, nullptr, BB);
3180 // This function is basically a switch over the CFI failure kind, which is
3181 // extracted from CFICheckFailData (1st function argument). Each case is either
3182 // llvm.trap or a call to one of the two runtime handlers, based on
3183 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid
3184 // failure kind) traps, but this should really never happen. CFICheckFailData
3185 // can be nullptr if the calling module has -fsanitize-trap behavior for this
3186 // check kind; in this case __cfi_check_fail traps as well.
3187 void CodeGenFunction::EmitCfiCheckFail() {
3188 SanitizerScope SanScope(this);
3189 FunctionArgList Args;
3190 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy,
3191 ImplicitParamDecl::Other);
3192 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy,
3193 ImplicitParamDecl::Other);
3194 Args.push_back(&ArgData);
3195 Args.push_back(&ArgAddr);
3197 const CGFunctionInfo &FI =
3198 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args);
3200 llvm::Function *F = llvm::Function::Create(
3201 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false),
3202 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule());
3203 F->setVisibility(llvm::GlobalValue::HiddenVisibility);
3205 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args,
3208 // This function should not be affected by blacklist. This function does
3209 // not have a source location, but "src:*" would still apply. Revert any
3210 // changes to SanOpts made in StartFunction.
3211 SanOpts = CGM.getLangOpts().Sanitize;
3214 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false,
3215 CGM.getContext().VoidPtrTy, ArgData.getLocation());
3217 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false,
3218 CGM.getContext().VoidPtrTy, ArgAddr.getLocation());
3220 // Data == nullptr means the calling module has trap behaviour for this check.
3221 llvm::Value *DataIsNotNullPtr =
3222 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy));
3223 EmitTrapCheck(DataIsNotNullPtr);
3225 llvm::StructType *SourceLocationTy =
3226 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty);
3227 llvm::StructType *CfiCheckFailDataTy =
3228 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy);
3230 llvm::Value *V = Builder.CreateConstGEP2_32(
3232 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0,
3234 Address CheckKindAddr(V, getIntAlign());
3235 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr);
3237 llvm::Value *AllVtables = llvm::MetadataAsValue::get(
3238 CGM.getLLVMContext(),
3239 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
3240 llvm::Value *ValidVtable = Builder.CreateZExt(
3241 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test),
3242 {Addr, AllVtables}),
3245 const std::pair<int, SanitizerMask> CheckKinds[] = {
3246 {CFITCK_VCall, SanitizerKind::CFIVCall},
3247 {CFITCK_NVCall, SanitizerKind::CFINVCall},
3248 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast},
3249 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast},
3250 {CFITCK_ICall, SanitizerKind::CFIICall}};
3252 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks;
3253 for (auto CheckKindMaskPair : CheckKinds) {
3254 int Kind = CheckKindMaskPair.first;
3255 SanitizerMask Mask = CheckKindMaskPair.second;
3257 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind));
3258 if (CGM.getLangOpts().Sanitize.has(Mask))
3259 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {},
3260 {Data, Addr, ValidVtable});
3262 EmitTrapCheck(Cond);
3266 // The only reference to this function will be created during LTO link.
3267 // Make sure it survives until then.
3268 CGM.addUsedGlobal(F);
3271 void CodeGenFunction::EmitUnreachable(SourceLocation Loc) {
3272 if (SanOpts.has(SanitizerKind::Unreachable)) {
3273 SanitizerScope SanScope(this);
3274 EmitCheck(std::make_pair(static_cast<llvm::Value *>(Builder.getFalse()),
3275 SanitizerKind::Unreachable),
3276 SanitizerHandler::BuiltinUnreachable,
3277 EmitCheckSourceLocation(Loc), None);
3279 Builder.CreateUnreachable();
3282 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
3283 llvm::BasicBlock *Cont = createBasicBlock("cont");
3285 // If we're optimizing, collapse all calls to trap down to just one per
3286 // function to save on code size.
3287 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
3288 TrapBB = createBasicBlock("trap");
3289 Builder.CreateCondBr(Checked, Cont, TrapBB);
3291 llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
3292 TrapCall->setDoesNotReturn();
3293 TrapCall->setDoesNotThrow();
3294 Builder.CreateUnreachable();
3296 Builder.CreateCondBr(Checked, Cont, TrapBB);
3302 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) {
3303 llvm::CallInst *TrapCall = Builder.CreateCall(CGM.getIntrinsic(IntrID));
3305 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
3306 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",
3307 CGM.getCodeGenOpts().TrapFuncName);
3308 TrapCall->addAttribute(llvm::AttributeList::FunctionIndex, A);
3314 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E,
3315 LValueBaseInfo *BaseInfo,
3316 TBAAAccessInfo *TBAAInfo) {
3317 assert(E->getType()->isArrayType() &&
3318 "Array to pointer decay must have array source type!");
3320 // Expressions of array type can't be bitfields or vector elements.
3321 LValue LV = EmitLValue(E);
3322 Address Addr = LV.getAddress();
3324 // If the array type was an incomplete type, we need to make sure
3325 // the decay ends up being the right type.
3326 llvm::Type *NewTy = ConvertType(E->getType());
3327 Addr = Builder.CreateElementBitCast(Addr, NewTy);
3329 // Note that VLA pointers are always decayed, so we don't need to do
3331 if (!E->getType()->isVariableArrayType()) {
3332 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3333 "Expected pointer to array");
3334 Addr = Builder.CreateConstArrayGEP(Addr, 0, "arraydecay");
3337 // The result of this decay conversion points to an array element within the
3338 // base lvalue. However, since TBAA currently does not support representing
3339 // accesses to elements of member arrays, we conservatively represent accesses
3340 // to the pointee object as if it had no any base lvalue specified.
3341 // TODO: Support TBAA for member arrays.
3342 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType();
3343 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
3344 if (TBAAInfo) *TBAAInfo = CGM.getTBAAAccessInfo(EltType);
3346 return Builder.CreateElementBitCast(Addr, ConvertTypeForMem(EltType));
3349 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
3350 /// array to pointer, return the array subexpression.
3351 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
3352 // If this isn't just an array->pointer decay, bail out.
3353 const auto *CE = dyn_cast<CastExpr>(E);
3354 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
3357 // If this is a decay from variable width array, bail out.
3358 const Expr *SubExpr = CE->getSubExpr();
3359 if (SubExpr->getType()->isVariableArrayType())
3365 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
3367 ArrayRef<llvm::Value*> indices,
3371 const llvm::Twine &name = "arrayidx") {
3373 return CGF.EmitCheckedInBoundsGEP(ptr, indices, signedIndices,
3374 CodeGenFunction::NotSubtraction, loc,
3377 return CGF.Builder.CreateGEP(ptr, indices, name);
3381 static CharUnits getArrayElementAlign(CharUnits arrayAlign,
3383 CharUnits eltSize) {
3384 // If we have a constant index, we can use the exact offset of the
3385 // element we're accessing.
3386 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) {
3387 CharUnits offset = constantIdx->getZExtValue() * eltSize;
3388 return arrayAlign.alignmentAtOffset(offset);
3390 // Otherwise, use the worst-case alignment for any element.
3392 return arrayAlign.alignmentOfArrayElement(eltSize);
3396 static QualType getFixedSizeElementType(const ASTContext &ctx,
3397 const VariableArrayType *vla) {
3400 eltType = vla->getElementType();
3401 } while ((vla = ctx.getAsVariableArrayType(eltType)));
3405 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
3406 ArrayRef<llvm::Value *> indices,
3407 QualType eltType, bool inbounds,
3408 bool signedIndices, SourceLocation loc,
3409 QualType *arrayType = nullptr,
3410 const llvm::Twine &name = "arrayidx") {
3411 // All the indices except that last must be zero.
3413 for (auto idx : indices.drop_back())
3414 assert(isa<llvm::ConstantInt>(idx) &&
3415 cast<llvm::ConstantInt>(idx)->isZero());
3418 // Determine the element size of the statically-sized base. This is
3419 // the thing that the indices are expressed in terms of.
3420 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) {
3421 eltType = getFixedSizeElementType(CGF.getContext(), vla);
3424 // We can use that to compute the best alignment of the element.
3425 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
3426 CharUnits eltAlign =
3427 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
3429 llvm::Value *eltPtr;
3430 auto LastIndex = dyn_cast<llvm::ConstantInt>(indices.back());
3431 if (!CGF.IsInPreservedAIRegion || !LastIndex) {
3432 eltPtr = emitArraySubscriptGEP(
3433 CGF, addr.getPointer(), indices, inbounds, signedIndices,
3436 // Remember the original array subscript for bpf target
3437 unsigned idx = LastIndex->getZExtValue();
3438 llvm::DIType *DbgInfo = nullptr;
3440 DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType(*arrayType, loc);
3441 eltPtr = CGF.Builder.CreatePreserveArrayAccessIndex(addr.getPointer(),
3446 return Address(eltPtr, eltAlign);
3449 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3451 // The index must always be an integer, which is not an aggregate. Emit it
3452 // in lexical order (this complexity is, sadly, required by C++17).
3453 llvm::Value *IdxPre =
3454 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr;
3455 bool SignedIndices = false;
3456 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * {
3458 if (E->getLHS() != E->getIdx()) {
3459 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS");
3460 Idx = EmitScalarExpr(E->getIdx());
3463 QualType IdxTy = E->getIdx()->getType();
3464 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
3465 SignedIndices |= IdxSigned;
3467 if (SanOpts.has(SanitizerKind::ArrayBounds))
3468 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
3470 // Extend or truncate the index type to 32 or 64-bits.
3471 if (Promote && Idx->getType() != IntPtrTy)
3472 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
3478 // If the base is a vector type, then we are forming a vector element lvalue
3479 // with this subscript.
3480 if (E->getBase()->getType()->isVectorType() &&
3481 !isa<ExtVectorElementExpr>(E->getBase())) {
3482 // Emit the vector as an lvalue to get its address.
3483 LValue LHS = EmitLValue(E->getBase());
3484 auto *Idx = EmitIdxAfterBase(/*Promote*/false);
3485 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
3486 return LValue::MakeVectorElt(LHS.getAddress(), Idx, E->getBase()->getType(),
3487 LHS.getBaseInfo(), TBAAAccessInfo());
3490 // All the other cases basically behave like simple offsetting.
3492 // Handle the extvector case we ignored above.
3493 if (isa<ExtVectorElementExpr>(E->getBase())) {
3494 LValue LV = EmitLValue(E->getBase());
3495 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3496 Address Addr = EmitExtVectorElementLValue(LV);
3498 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
3499 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true,
3500 SignedIndices, E->getExprLoc());
3501 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo(),
3502 CGM.getTBAAInfoForSubobject(LV, EltType));
3505 LValueBaseInfo EltBaseInfo;
3506 TBAAAccessInfo EltTBAAInfo;
3507 Address Addr = Address::invalid();
3508 if (const VariableArrayType *vla =
3509 getContext().getAsVariableArrayType(E->getType())) {
3510 // The base must be a pointer, which is not an aggregate. Emit
3511 // it. It needs to be emitted first in case it's what captures
3513 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3514 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3516 // The element count here is the total number of non-VLA elements.
3517 llvm::Value *numElements = getVLASize(vla).NumElts;
3519 // Effectively, the multiply by the VLA size is part of the GEP.
3520 // GEP indexes are signed, and scaling an index isn't permitted to
3521 // signed-overflow, so we use the same semantics for our explicit
3522 // multiply. We suppress this if overflow is not undefined behavior.
3523 if (getLangOpts().isSignedOverflowDefined()) {
3524 Idx = Builder.CreateMul(Idx, numElements);
3526 Idx = Builder.CreateNSWMul(Idx, numElements);
3529 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
3530 !getLangOpts().isSignedOverflowDefined(),
3531 SignedIndices, E->getExprLoc());
3533 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
3534 // Indexing over an interface, as in "NSString *P; P[4];"
3536 // Emit the base pointer.
3537 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3538 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3540 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT);
3541 llvm::Value *InterfaceSizeVal =
3542 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity());
3544 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal);
3546 // We don't necessarily build correct LLVM struct types for ObjC
3547 // interfaces, so we can't rely on GEP to do this scaling
3548 // correctly, so we need to cast to i8*. FIXME: is this actually
3549 // true? A lot of other things in the fragile ABI would break...
3550 llvm::Type *OrigBaseTy = Addr.getType();
3551 Addr = Builder.CreateElementBitCast(Addr, Int8Ty);
3554 CharUnits EltAlign =
3555 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
3556 llvm::Value *EltPtr =
3557 emitArraySubscriptGEP(*this, Addr.getPointer(), ScaledIdx, false,
3558 SignedIndices, E->getExprLoc());
3559 Addr = Address(EltPtr, EltAlign);
3562 Addr = Builder.CreateBitCast(Addr, OrigBaseTy);
3563 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3564 // If this is A[i] where A is an array, the frontend will have decayed the
3565 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3566 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3567 // "gep x, i" here. Emit one "gep A, 0, i".
3568 assert(Array->getType()->isArrayType() &&
3569 "Array to pointer decay must have array source type!");
3571 // For simple multidimensional array indexing, set the 'accessed' flag for
3572 // better bounds-checking of the base expression.
3573 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3574 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3576 ArrayLV = EmitLValue(Array);
3577 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3579 // Propagate the alignment from the array itself to the result.
3580 QualType arrayType = Array->getType();
3581 Addr = emitArraySubscriptGEP(
3582 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3583 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices,
3584 E->getExprLoc(), &arrayType);
3585 EltBaseInfo = ArrayLV.getBaseInfo();
3586 EltTBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, E->getType());
3588 // The base must be a pointer; emit it with an estimate of its alignment.
3589 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3590 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3591 QualType ptrType = E->getBase()->getType();
3592 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
3593 !getLangOpts().isSignedOverflowDefined(),
3594 SignedIndices, E->getExprLoc(), &ptrType);
3597 LValue LV = MakeAddrLValue(Addr, E->getType(), EltBaseInfo, EltTBAAInfo);
3599 if (getLangOpts().ObjC &&
3600 getLangOpts().getGC() != LangOptions::NonGC) {
3601 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
3602 setObjCGCLValueClass(getContext(), E, LV);
3607 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base,
3608 LValueBaseInfo &BaseInfo,
3609 TBAAAccessInfo &TBAAInfo,
3610 QualType BaseTy, QualType ElTy,
3611 bool IsLowerBound) {
3613 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) {
3614 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound);
3615 if (BaseTy->isArrayType()) {
3616 Address Addr = BaseLVal.getAddress();
3617 BaseInfo = BaseLVal.getBaseInfo();
3619 // If the array type was an incomplete type, we need to make sure
3620 // the decay ends up being the right type.
3621 llvm::Type *NewTy = CGF.ConvertType(BaseTy);
3622 Addr = CGF.Builder.CreateElementBitCast(Addr, NewTy);
3624 // Note that VLA pointers are always decayed, so we don't need to do
3626 if (!BaseTy->isVariableArrayType()) {
3627 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3628 "Expected pointer to array");
3629 Addr = CGF.Builder.CreateConstArrayGEP(Addr, 0, "arraydecay");
3632 return CGF.Builder.CreateElementBitCast(Addr,
3633 CGF.ConvertTypeForMem(ElTy));
3635 LValueBaseInfo TypeBaseInfo;
3636 TBAAAccessInfo TypeTBAAInfo;
3637 CharUnits Align = CGF.getNaturalTypeAlignment(ElTy, &TypeBaseInfo,
3639 BaseInfo.mergeForCast(TypeBaseInfo);
3640 TBAAInfo = CGF.CGM.mergeTBAAInfoForCast(TBAAInfo, TypeTBAAInfo);
3641 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress()), Align);
3643 return CGF.EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo);
3646 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3647 bool IsLowerBound) {
3648 QualType BaseTy = OMPArraySectionExpr::getBaseOriginalType(E->getBase());
3649 QualType ResultExprTy;
3650 if (auto *AT = getContext().getAsArrayType(BaseTy))
3651 ResultExprTy = AT->getElementType();
3653 ResultExprTy = BaseTy->getPointeeType();
3654 llvm::Value *Idx = nullptr;
3655 if (IsLowerBound || E->getColonLoc().isInvalid()) {
3656 // Requesting lower bound or upper bound, but without provided length and
3657 // without ':' symbol for the default length -> length = 1.
3658 // Idx = LowerBound ?: 0;
3659 if (auto *LowerBound = E->getLowerBound()) {
3660 Idx = Builder.CreateIntCast(
3661 EmitScalarExpr(LowerBound), IntPtrTy,
3662 LowerBound->getType()->hasSignedIntegerRepresentation());
3664 Idx = llvm::ConstantInt::getNullValue(IntPtrTy);
3666 // Try to emit length or lower bound as constant. If this is possible, 1
3667 // is subtracted from constant length or lower bound. Otherwise, emit LLVM
3668 // IR (LB + Len) - 1.
3669 auto &C = CGM.getContext();
3670 auto *Length = E->getLength();
3671 llvm::APSInt ConstLength;
3673 // Idx = LowerBound + Length - 1;
3674 if (Length->isIntegerConstantExpr(ConstLength, C)) {
3675 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3678 auto *LowerBound = E->getLowerBound();
3679 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false);
3680 if (LowerBound && LowerBound->isIntegerConstantExpr(ConstLowerBound, C)) {
3681 ConstLowerBound = ConstLowerBound.zextOrTrunc(PointerWidthInBits);
3682 LowerBound = nullptr;
3686 else if (!LowerBound)
3689 if (Length || LowerBound) {
3690 auto *LowerBoundVal =
3692 ? Builder.CreateIntCast(
3693 EmitScalarExpr(LowerBound), IntPtrTy,
3694 LowerBound->getType()->hasSignedIntegerRepresentation())
3695 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound);
3698 ? Builder.CreateIntCast(
3699 EmitScalarExpr(Length), IntPtrTy,
3700 Length->getType()->hasSignedIntegerRepresentation())
3701 : llvm::ConstantInt::get(IntPtrTy, ConstLength);
3702 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len",
3704 !getLangOpts().isSignedOverflowDefined());
3705 if (Length && LowerBound) {
3706 Idx = Builder.CreateSub(
3707 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1",
3708 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3711 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound);
3713 // Idx = ArraySize - 1;
3714 QualType ArrayTy = BaseTy->isPointerType()
3715 ? E->getBase()->IgnoreParenImpCasts()->getType()
3717 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) {
3718 Length = VAT->getSizeExpr();
3719 if (Length->isIntegerConstantExpr(ConstLength, C))
3722 auto *CAT = C.getAsConstantArrayType(ArrayTy);
3723 ConstLength = CAT->getSize();
3726 auto *LengthVal = Builder.CreateIntCast(
3727 EmitScalarExpr(Length), IntPtrTy,
3728 Length->getType()->hasSignedIntegerRepresentation());
3729 Idx = Builder.CreateSub(
3730 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1",
3731 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3733 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3735 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength);
3741 Address EltPtr = Address::invalid();
3742 LValueBaseInfo BaseInfo;
3743 TBAAAccessInfo TBAAInfo;
3744 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) {
3745 // The base must be a pointer, which is not an aggregate. Emit
3746 // it. It needs to be emitted first in case it's what captures
3749 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo,
3750 BaseTy, VLA->getElementType(), IsLowerBound);
3751 // The element count here is the total number of non-VLA elements.
3752 llvm::Value *NumElements = getVLASize(VLA).NumElts;
3754 // Effectively, the multiply by the VLA size is part of the GEP.
3755 // GEP indexes are signed, and scaling an index isn't permitted to
3756 // signed-overflow, so we use the same semantics for our explicit
3757 // multiply. We suppress this if overflow is not undefined behavior.
3758 if (getLangOpts().isSignedOverflowDefined())
3759 Idx = Builder.CreateMul(Idx, NumElements);
3761 Idx = Builder.CreateNSWMul(Idx, NumElements);
3762 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
3763 !getLangOpts().isSignedOverflowDefined(),
3764 /*signedIndices=*/false, E->getExprLoc());
3765 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3766 // If this is A[i] where A is an array, the frontend will have decayed the
3767 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3768 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3769 // "gep x, i" here. Emit one "gep A, 0, i".
3770 assert(Array->getType()->isArrayType() &&
3771 "Array to pointer decay must have array source type!");
3773 // For simple multidimensional array indexing, set the 'accessed' flag for
3774 // better bounds-checking of the base expression.
3775 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3776 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3778 ArrayLV = EmitLValue(Array);
3780 // Propagate the alignment from the array itself to the result.
3781 EltPtr = emitArraySubscriptGEP(
3782 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3783 ResultExprTy, !getLangOpts().isSignedOverflowDefined(),
3784 /*signedIndices=*/false, E->getExprLoc());
3785 BaseInfo = ArrayLV.getBaseInfo();
3786 TBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, ResultExprTy);
3788 Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo,
3789 TBAAInfo, BaseTy, ResultExprTy,
3791 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
3792 !getLangOpts().isSignedOverflowDefined(),
3793 /*signedIndices=*/false, E->getExprLoc());
3796 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo, TBAAInfo);
3799 LValue CodeGenFunction::
3800 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
3801 // Emit the base vector as an l-value.
3804 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
3806 // If it is a pointer to a vector, emit the address and form an lvalue with
3808 LValueBaseInfo BaseInfo;
3809 TBAAAccessInfo TBAAInfo;
3810 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo, &TBAAInfo);
3811 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
3812 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo, TBAAInfo);
3813 Base.getQuals().removeObjCGCAttr();
3814 } else if (E->getBase()->isGLValue()) {
3815 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
3816 // emit the base as an lvalue.
3817 assert(E->getBase()->getType()->isVectorType());
3818 Base = EmitLValue(E->getBase());
3820 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
3821 assert(E->getBase()->getType()->isVectorType() &&
3822 "Result must be a vector");
3823 llvm::Value *Vec = EmitScalarExpr(E->getBase());
3825 // Store the vector to memory (because LValue wants an address).
3826 Address VecMem = CreateMemTemp(E->getBase()->getType());
3827 Builder.CreateStore(Vec, VecMem);
3828 Base = MakeAddrLValue(VecMem, E->getBase()->getType(),
3829 AlignmentSource::Decl);
3833 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
3835 // Encode the element access list into a vector of unsigned indices.
3836 SmallVector<uint32_t, 4> Indices;
3837 E->getEncodedElementAccess(Indices);
3839 if (Base.isSimple()) {
3840 llvm::Constant *CV =
3841 llvm::ConstantDataVector::get(getLLVMContext(), Indices);
3842 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
3843 Base.getBaseInfo(), TBAAAccessInfo());
3845 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
3847 llvm::Constant *BaseElts = Base.getExtVectorElts();
3848 SmallVector<llvm::Constant *, 4> CElts;
3850 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
3851 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
3852 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
3853 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type,
3854 Base.getBaseInfo(), TBAAAccessInfo());
3857 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
3858 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, E)) {
3859 EmitIgnoredExpr(E->getBase());
3860 return EmitDeclRefLValue(DRE);
3863 Expr *BaseExpr = E->getBase();
3864 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
3867 LValueBaseInfo BaseInfo;
3868 TBAAAccessInfo TBAAInfo;
3869 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo, &TBAAInfo);
3870 QualType PtrTy = BaseExpr->getType()->getPointeeType();
3871 SanitizerSet SkippedChecks;
3872 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr);
3874 SkippedChecks.set(SanitizerKind::Alignment, true);
3875 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr))
3876 SkippedChecks.set(SanitizerKind::Null, true);
3877 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy,
3878 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
3879 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo, TBAAInfo);
3881 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
3883 NamedDecl *ND = E->getMemberDecl();
3884 if (auto *Field = dyn_cast<FieldDecl>(ND)) {
3885 LValue LV = EmitLValueForField(BaseLV, Field);
3886 setObjCGCLValueClass(getContext(), E, LV);
3890 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
3891 return EmitFunctionDeclLValue(*this, E, FD);
3893 llvm_unreachable("Unhandled member declaration!");
3896 /// Given that we are currently emitting a lambda, emit an l-value for
3897 /// one of its members.
3898 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
3899 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
3900 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
3901 QualType LambdaTagType =
3902 getContext().getTagDeclType(Field->getParent());
3903 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
3904 return EmitLValueForField(LambdaLV, Field);
3907 /// Get the field index in the debug info. The debug info structure/union
3908 /// will ignore the unnamed bitfields.
3909 unsigned CodeGenFunction::getDebugInfoFIndex(const RecordDecl *Rec,
3910 unsigned FieldIndex) {
3911 unsigned I = 0, Skipped = 0;
3913 for (auto F : Rec->getDefinition()->fields()) {
3914 if (I == FieldIndex)
3916 if (F->isUnnamedBitfield())
3921 return FieldIndex - Skipped;
3924 /// Get the address of a zero-sized field within a record. The resulting
3925 /// address doesn't necessarily have the right type.
3926 static Address emitAddrOfZeroSizeField(CodeGenFunction &CGF, Address Base,
3927 const FieldDecl *Field) {
3928 CharUnits Offset = CGF.getContext().toCharUnitsFromBits(
3929 CGF.getContext().getFieldOffset(Field));
3930 if (Offset.isZero())
3932 Base = CGF.Builder.CreateElementBitCast(Base, CGF.Int8Ty);
3933 return CGF.Builder.CreateConstInBoundsByteGEP(Base, Offset);
3936 /// Drill down to the storage of a field without walking into
3937 /// reference types.
3939 /// The resulting address doesn't necessarily have the right type.
3940 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
3941 const FieldDecl *field) {
3942 if (field->isZeroSize(CGF.getContext()))
3943 return emitAddrOfZeroSizeField(CGF, base, field);
3945 const RecordDecl *rec = field->getParent();
3948 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
3950 return CGF.Builder.CreateStructGEP(base, idx, field->getName());
3953 static Address emitPreserveStructAccess(CodeGenFunction &CGF, Address base,
3954 const FieldDecl *field) {
3955 const RecordDecl *rec = field->getParent();
3956 llvm::DIType *DbgInfo = CGF.getDebugInfo()->getOrCreateRecordType(
3957 CGF.getContext().getRecordType(rec), rec->getLocation());
3960 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
3962 return CGF.Builder.CreatePreserveStructAccessIndex(
3963 base, idx, CGF.getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo);
3966 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) {
3967 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl();
3971 if (RD->isDynamicClass())
3974 for (const auto &Base : RD->bases())
3975 if (hasAnyVptr(Base.getType(), Context))
3978 for (const FieldDecl *Field : RD->fields())
3979 if (hasAnyVptr(Field->getType(), Context))
3985 LValue CodeGenFunction::EmitLValueForField(LValue base,
3986 const FieldDecl *field) {
3987 LValueBaseInfo BaseInfo = base.getBaseInfo();
3989 if (field->isBitField()) {
3990 const CGRecordLayout &RL =
3991 CGM.getTypes().getCGRecordLayout(field->getParent());
3992 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
3993 Address Addr = base.getAddress();
3994 unsigned Idx = RL.getLLVMFieldNo(field);
3995 if (!IsInPreservedAIRegion) {
3997 // For structs, we GEP to the field that the record layout suggests.
3998 Addr = Builder.CreateStructGEP(Addr, Idx, field->getName());
4000 const RecordDecl *rec = field->getParent();
4001 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateRecordType(
4002 getContext().getRecordType(rec), rec->getLocation());
4003 Addr = Builder.CreatePreserveStructAccessIndex(Addr, Idx,
4004 getDebugInfoFIndex(rec, field->getFieldIndex()),
4008 // Get the access type.
4009 llvm::Type *FieldIntTy =
4010 llvm::Type::getIntNTy(getLLVMContext(), Info.StorageSize);
4011 if (Addr.getElementType() != FieldIntTy)
4012 Addr = Builder.CreateElementBitCast(Addr, FieldIntTy);
4014 QualType fieldType =
4015 field->getType().withCVRQualifiers(base.getVRQualifiers());
4016 // TODO: Support TBAA for bit fields.
4017 LValueBaseInfo FieldBaseInfo(BaseInfo.getAlignmentSource());
4018 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo,
4022 // Fields of may-alias structures are may-alias themselves.
4023 // FIXME: this should get propagated down through anonymous structs
4025 QualType FieldType = field->getType();
4026 const RecordDecl *rec = field->getParent();
4027 AlignmentSource BaseAlignSource = BaseInfo.getAlignmentSource();
4028 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(BaseAlignSource));
4029 TBAAAccessInfo FieldTBAAInfo;
4030 if (base.getTBAAInfo().isMayAlias() ||
4031 rec->hasAttr<MayAliasAttr>() || FieldType->isVectorType()) {
4032 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
4033 } else if (rec->isUnion()) {
4034 // TODO: Support TBAA for unions.
4035 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
4037 // If no base type been assigned for the base access, then try to generate
4038 // one for this base lvalue.
4039 FieldTBAAInfo = base.getTBAAInfo();
4040 if (!FieldTBAAInfo.BaseType) {
4041 FieldTBAAInfo.BaseType = CGM.getTBAABaseTypeInfo(base.getType());
4042 assert(!FieldTBAAInfo.Offset &&
4043 "Nonzero offset for an access with no base type!");
4046 // Adjust offset to be relative to the base type.
4047 const ASTRecordLayout &Layout =
4048 getContext().getASTRecordLayout(field->getParent());
4049 unsigned CharWidth = getContext().getCharWidth();
4050 if (FieldTBAAInfo.BaseType)
4051 FieldTBAAInfo.Offset +=
4052 Layout.getFieldOffset(field->getFieldIndex()) / CharWidth;
4054 // Update the final access type and size.
4055 FieldTBAAInfo.AccessType = CGM.getTBAATypeInfo(FieldType);
4056 FieldTBAAInfo.Size =
4057 getContext().getTypeSizeInChars(FieldType).getQuantity();
4060 Address addr = base.getAddress();
4061 if (auto *ClassDef = dyn_cast<CXXRecordDecl>(rec)) {
4062 if (CGM.getCodeGenOpts().StrictVTablePointers &&
4063 ClassDef->isDynamicClass()) {
4064 // Getting to any field of dynamic object requires stripping dynamic
4065 // information provided by invariant.group. This is because accessing
4066 // fields may leak the real address of dynamic object, which could result
4067 // in miscompilation when leaked pointer would be compared.
4068 auto *stripped = Builder.CreateStripInvariantGroup(addr.getPointer());
4069 addr = Address(stripped, addr.getAlignment());
4073 unsigned RecordCVR = base.getVRQualifiers();
4074 if (rec->isUnion()) {
4075 // For unions, there is no pointer adjustment.
4076 if (CGM.getCodeGenOpts().StrictVTablePointers &&
4077 hasAnyVptr(FieldType, getContext()))
4078 // Because unions can easily skip invariant.barriers, we need to add
4079 // a barrier every time CXXRecord field with vptr is referenced.
4080 addr = Address(Builder.CreateLaunderInvariantGroup(addr.getPointer()),
4081 addr.getAlignment());
4083 if (IsInPreservedAIRegion) {
4084 // Remember the original union field index
4085 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateRecordType(
4086 getContext().getRecordType(rec), rec->getLocation());
4088 Builder.CreatePreserveUnionAccessIndex(
4089 addr.getPointer(), getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo),
4090 addr.getAlignment());
4093 if (FieldType->isReferenceType())
4094 addr = Builder.CreateElementBitCast(
4095 addr, CGM.getTypes().ConvertTypeForMem(FieldType), field->getName());
4097 if (!IsInPreservedAIRegion)
4098 // For structs, we GEP to the field that the record layout suggests.
4099 addr = emitAddrOfFieldStorage(*this, addr, field);
4101 // Remember the original struct field index
4102 addr = emitPreserveStructAccess(*this, addr, field);
4105 // If this is a reference field, load the reference right now.
4106 if (FieldType->isReferenceType()) {
4108 MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
4109 if (RecordCVR & Qualifiers::Volatile)
4110 RefLVal.getQuals().addVolatile();
4111 addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo);
4113 // Qualifiers on the struct don't apply to the referencee.
4115 FieldType = FieldType->getPointeeType();
4118 // Make sure that the address is pointing to the right type. This is critical
4119 // for both unions and structs. A union needs a bitcast, a struct element
4120 // will need a bitcast if the LLVM type laid out doesn't match the desired
4122 addr = Builder.CreateElementBitCast(
4123 addr, CGM.getTypes().ConvertTypeForMem(FieldType), field->getName());
4125 if (field->hasAttr<AnnotateAttr>())
4126 addr = EmitFieldAnnotations(field, addr);
4128 LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
4129 LV.getQuals().addCVRQualifiers(RecordCVR);
4131 // __weak attribute on a field is ignored.
4132 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
4133 LV.getQuals().removeObjCGCAttr();
4139 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
4140 const FieldDecl *Field) {
4141 QualType FieldType = Field->getType();
4143 if (!FieldType->isReferenceType())
4144 return EmitLValueForField(Base, Field);
4146 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(), Field);
4148 // Make sure that the address is pointing to the right type.
4149 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
4150 V = Builder.CreateElementBitCast(V, llvmType, Field->getName());
4152 // TODO: Generate TBAA information that describes this access as a structure
4153 // member access and not just an access to an object of the field's type. This
4154 // should be similar to what we do in EmitLValueForField().
4155 LValueBaseInfo BaseInfo = Base.getBaseInfo();
4156 AlignmentSource FieldAlignSource = BaseInfo.getAlignmentSource();
4157 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(FieldAlignSource));
4158 return MakeAddrLValue(V, FieldType, FieldBaseInfo,
4159 CGM.getTBAAInfoForSubobject(Base, FieldType));
4162 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
4163 if (E->isFileScope()) {
4164 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
4165 return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl);
4167 if (E->getType()->isVariablyModifiedType())
4168 // make sure to emit the VLA size.
4169 EmitVariablyModifiedType(E->getType());
4171 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
4172 const Expr *InitExpr = E->getInitializer();
4173 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl);
4175 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
4181 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
4182 if (!E->isGLValue())
4183 // Initializing an aggregate temporary in C++11: T{...}.
4184 return EmitAggExprToLValue(E);
4186 // An lvalue initializer list must be initializing a reference.
4187 assert(E->isTransparent() && "non-transparent glvalue init list");
4188 return EmitLValue(E->getInit(0));
4191 /// Emit the operand of a glvalue conditional operator. This is either a glvalue
4192 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no
4193 /// LValue is returned and the current block has been terminated.
4194 static Optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
4195 const Expr *Operand) {
4196 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
4197 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
4201 return CGF.EmitLValue(Operand);
4204 LValue CodeGenFunction::
4205 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
4206 if (!expr->isGLValue()) {
4207 // ?: here should be an aggregate.
4208 assert(hasAggregateEvaluationKind(expr->getType()) &&
4209 "Unexpected conditional operator!");
4210 return EmitAggExprToLValue(expr);
4213 OpaqueValueMapping binding(*this, expr);
4215 const Expr *condExpr = expr->getCond();
4217 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
4218 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
4219 if (!CondExprBool) std::swap(live, dead);
4221 if (!ContainsLabel(dead)) {
4222 // If the true case is live, we need to track its region.
4224 incrementProfileCounter(expr);
4225 return EmitLValue(live);
4229 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
4230 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
4231 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
4233 ConditionalEvaluation eval(*this);
4234 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock, getProfileCount(expr));
4236 // Any temporaries created here are conditional.
4237 EmitBlock(lhsBlock);
4238 incrementProfileCounter(expr);
4240 Optional<LValue> lhs =
4241 EmitLValueOrThrowExpression(*this, expr->getTrueExpr());
4244 if (lhs && !lhs->isSimple())
4245 return EmitUnsupportedLValue(expr, "conditional operator");
4247 lhsBlock = Builder.GetInsertBlock();
4249 Builder.CreateBr(contBlock);
4251 // Any temporaries created here are conditional.
4252 EmitBlock(rhsBlock);
4254 Optional<LValue> rhs =
4255 EmitLValueOrThrowExpression(*this, expr->getFalseExpr());
4257 if (rhs && !rhs->isSimple())
4258 return EmitUnsupportedLValue(expr, "conditional operator");
4259 rhsBlock = Builder.GetInsertBlock();
4261 EmitBlock(contBlock);
4264 llvm::PHINode *phi = Builder.CreatePHI(lhs->getPointer()->getType(),
4266 phi->addIncoming(lhs->getPointer(), lhsBlock);
4267 phi->addIncoming(rhs->getPointer(), rhsBlock);
4268 Address result(phi, std::min(lhs->getAlignment(), rhs->getAlignment()));
4269 AlignmentSource alignSource =
4270 std::max(lhs->getBaseInfo().getAlignmentSource(),
4271 rhs->getBaseInfo().getAlignmentSource());
4272 TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForConditionalOperator(
4273 lhs->getTBAAInfo(), rhs->getTBAAInfo());
4274 return MakeAddrLValue(result, expr->getType(), LValueBaseInfo(alignSource),
4277 assert((lhs || rhs) &&
4278 "both operands of glvalue conditional are throw-expressions?");
4279 return lhs ? *lhs : *rhs;
4283 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
4284 /// type. If the cast is to a reference, we can have the usual lvalue result,
4285 /// otherwise if a cast is needed by the code generator in an lvalue context,
4286 /// then it must mean that we need the address of an aggregate in order to
4287 /// access one of its members. This can happen for all the reasons that casts
4288 /// are permitted with aggregate result, including noop aggregate casts, and
4289 /// cast from scalar to union.
4290 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
4291 switch (E->getCastKind()) {
4294 case CK_LValueToRValueBitCast:
4295 case CK_ArrayToPointerDecay:
4296 case CK_FunctionToPointerDecay:
4297 case CK_NullToMemberPointer:
4298 case CK_NullToPointer:
4299 case CK_IntegralToPointer:
4300 case CK_PointerToIntegral:
4301 case CK_PointerToBoolean:
4302 case CK_VectorSplat:
4303 case CK_IntegralCast:
4304 case CK_BooleanToSignedIntegral:
4305 case CK_IntegralToBoolean:
4306 case CK_IntegralToFloating:
4307 case CK_FloatingToIntegral:
4308 case CK_FloatingToBoolean:
4309 case CK_FloatingCast:
4310 case CK_FloatingRealToComplex:
4311 case CK_FloatingComplexToReal:
4312 case CK_FloatingComplexToBoolean:
4313 case CK_FloatingComplexCast:
4314 case CK_FloatingComplexToIntegralComplex:
4315 case CK_IntegralRealToComplex:
4316 case CK_IntegralComplexToReal:
4317 case CK_IntegralComplexToBoolean:
4318 case CK_IntegralComplexCast:
4319 case CK_IntegralComplexToFloatingComplex:
4320 case CK_DerivedToBaseMemberPointer:
4321 case CK_BaseToDerivedMemberPointer:
4322 case CK_MemberPointerToBoolean:
4323 case CK_ReinterpretMemberPointer:
4324 case CK_AnyPointerToBlockPointerCast:
4325 case CK_ARCProduceObject:
4326 case CK_ARCConsumeObject:
4327 case CK_ARCReclaimReturnedObject:
4328 case CK_ARCExtendBlockObject:
4329 case CK_CopyAndAutoreleaseBlockObject:
4330 case CK_IntToOCLSampler:
4331 case CK_FixedPointCast:
4332 case CK_FixedPointToBoolean:
4333 case CK_FixedPointToIntegral:
4334 case CK_IntegralToFixedPoint:
4335 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
4338 llvm_unreachable("dependent cast kind in IR gen!");
4340 case CK_BuiltinFnToFnPtr:
4341 llvm_unreachable("builtin functions are handled elsewhere");
4343 // These are never l-values; just use the aggregate emission code.
4344 case CK_NonAtomicToAtomic:
4345 case CK_AtomicToNonAtomic:
4346 return EmitAggExprToLValue(E);
4349 LValue LV = EmitLValue(E->getSubExpr());
4350 Address V = LV.getAddress();
4351 const auto *DCE = cast<CXXDynamicCastExpr>(E);
4352 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType());
4355 case CK_ConstructorConversion:
4356 case CK_UserDefinedConversion:
4357 case CK_CPointerToObjCPointerCast:
4358 case CK_BlockPointerToObjCPointerCast:
4360 case CK_LValueToRValue:
4361 return EmitLValue(E->getSubExpr());
4363 case CK_UncheckedDerivedToBase:
4364 case CK_DerivedToBase: {
4365 const RecordType *DerivedClassTy =
4366 E->getSubExpr()->getType()->getAs<RecordType>();
4367 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
4369 LValue LV = EmitLValue(E->getSubExpr());
4370 Address This = LV.getAddress();
4372 // Perform the derived-to-base conversion
4373 Address Base = GetAddressOfBaseClass(
4374 This, DerivedClassDecl, E->path_begin(), E->path_end(),
4375 /*NullCheckValue=*/false, E->getExprLoc());
4377 // TODO: Support accesses to members of base classes in TBAA. For now, we
4378 // conservatively pretend that the complete object is of the base class
4380 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo(),
4381 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4384 return EmitAggExprToLValue(E);
4385 case CK_BaseToDerived: {
4386 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
4387 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
4389 LValue LV = EmitLValue(E->getSubExpr());
4391 // Perform the base-to-derived conversion
4393 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
4394 E->path_begin(), E->path_end(),
4395 /*NullCheckValue=*/false);
4397 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
4398 // performed and the object is not of the derived type.
4399 if (sanitizePerformTypeCheck())
4400 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
4401 Derived.getPointer(), E->getType());
4403 if (SanOpts.has(SanitizerKind::CFIDerivedCast))
4404 EmitVTablePtrCheckForCast(E->getType(), Derived.getPointer(),
4405 /*MayBeNull=*/false, CFITCK_DerivedCast,
4408 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo(),
4409 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4411 case CK_LValueBitCast: {
4412 // This must be a reinterpret_cast (or c-style equivalent).
4413 const auto *CE = cast<ExplicitCastExpr>(E);
4415 CGM.EmitExplicitCastExprType(CE, this);
4416 LValue LV = EmitLValue(E->getSubExpr());
4417 Address V = Builder.CreateBitCast(LV.getAddress(),
4418 ConvertType(CE->getTypeAsWritten()));
4420 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast))
4421 EmitVTablePtrCheckForCast(E->getType(), V.getPointer(),
4422 /*MayBeNull=*/false, CFITCK_UnrelatedCast,
4425 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
4426 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4428 case CK_AddressSpaceConversion: {
4429 LValue LV = EmitLValue(E->getSubExpr());
4430 QualType DestTy = getContext().getPointerType(E->getType());
4431 llvm::Value *V = getTargetHooks().performAddrSpaceCast(
4432 *this, LV.getPointer(), E->getSubExpr()->getType().getAddressSpace(),
4433 E->getType().getAddressSpace(), ConvertType(DestTy));
4434 return MakeAddrLValue(Address(V, LV.getAddress().getAlignment()),
4435 E->getType(), LV.getBaseInfo(), LV.getTBAAInfo());
4437 case CK_ObjCObjectLValueCast: {
4438 LValue LV = EmitLValue(E->getSubExpr());
4439 Address V = Builder.CreateElementBitCast(LV.getAddress(),
4440 ConvertType(E->getType()));
4441 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
4442 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4444 case CK_ZeroToOCLOpaqueType:
4445 llvm_unreachable("NULL to OpenCL opaque type lvalue cast is not valid");
4448 llvm_unreachable("Unhandled lvalue cast kind?");
4451 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
4452 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
4453 return getOrCreateOpaqueLValueMapping(e);
4457 CodeGenFunction::getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e) {
4458 assert(OpaqueValueMapping::shouldBindAsLValue(e));
4460 llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator
4461 it = OpaqueLValues.find(e);
4463 if (it != OpaqueLValues.end())
4466 assert(e->isUnique() && "LValue for a nonunique OVE hasn't been emitted");
4467 return EmitLValue(e->getSourceExpr());
4471 CodeGenFunction::getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e) {
4472 assert(!OpaqueValueMapping::shouldBindAsLValue(e));
4474 llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator
4475 it = OpaqueRValues.find(e);
4477 if (it != OpaqueRValues.end())
4480 assert(e->isUnique() && "RValue for a nonunique OVE hasn't been emitted");
4481 return EmitAnyExpr(e->getSourceExpr());
4484 RValue CodeGenFunction::EmitRValueForField(LValue LV,
4485 const FieldDecl *FD,
4486 SourceLocation Loc) {
4487 QualType FT = FD->getType();
4488 LValue FieldLV = EmitLValueForField(LV, FD);
4489 switch (getEvaluationKind(FT)) {
4491 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
4493 return FieldLV.asAggregateRValue();
4495 // This routine is used to load fields one-by-one to perform a copy, so
4496 // don't load reference fields.
4497 if (FD->getType()->isReferenceType())
4498 return RValue::get(FieldLV.getPointer());
4499 return EmitLoadOfLValue(FieldLV, Loc);
4501 llvm_unreachable("bad evaluation kind");
4504 //===--------------------------------------------------------------------===//
4505 // Expression Emission
4506 //===--------------------------------------------------------------------===//
4508 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
4509 ReturnValueSlot ReturnValue) {
4510 // Builtins never have block type.
4511 if (E->getCallee()->getType()->isBlockPointerType())
4512 return EmitBlockCallExpr(E, ReturnValue);
4514 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
4515 return EmitCXXMemberCallExpr(CE, ReturnValue);
4517 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
4518 return EmitCUDAKernelCallExpr(CE, ReturnValue);
4520 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
4521 if (const CXXMethodDecl *MD =
4522 dyn_cast_or_null<CXXMethodDecl>(CE->getCalleeDecl()))
4523 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
4525 CGCallee callee = EmitCallee(E->getCallee());
4527 if (callee.isBuiltin()) {
4528 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(),
4532 if (callee.isPseudoDestructor()) {
4533 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr());
4536 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue);
4539 /// Emit a CallExpr without considering whether it might be a subclass.
4540 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E,
4541 ReturnValueSlot ReturnValue) {
4542 CGCallee Callee = EmitCallee(E->getCallee());
4543 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue);
4546 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, const FunctionDecl *FD) {
4547 if (auto builtinID = FD->getBuiltinID()) {
4548 return CGCallee::forBuiltin(builtinID, FD);
4551 llvm::Constant *calleePtr = EmitFunctionDeclPointer(CGF.CGM, FD);
4552 return CGCallee::forDirect(calleePtr, GlobalDecl(FD));
4555 CGCallee CodeGenFunction::EmitCallee(const Expr *E) {
4556 E = E->IgnoreParens();
4558 // Look through function-to-pointer decay.
4559 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) {
4560 if (ICE->getCastKind() == CK_FunctionToPointerDecay ||
4561 ICE->getCastKind() == CK_BuiltinFnToFnPtr) {
4562 return EmitCallee(ICE->getSubExpr());
4565 // Resolve direct calls.
4566 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) {
4567 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
4568 return EmitDirectCallee(*this, FD);
4570 } else if (auto ME = dyn_cast<MemberExpr>(E)) {
4571 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) {
4572 EmitIgnoredExpr(ME->getBase());
4573 return EmitDirectCallee(*this, FD);
4576 // Look through template substitutions.
4577 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
4578 return EmitCallee(NTTP->getReplacement());
4580 // Treat pseudo-destructor calls differently.
4581 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) {
4582 return CGCallee::forPseudoDestructor(PDE);
4585 // Otherwise, we have an indirect reference.
4586 llvm::Value *calleePtr;
4587 QualType functionType;
4588 if (auto ptrType = E->getType()->getAs<PointerType>()) {
4589 calleePtr = EmitScalarExpr(E);
4590 functionType = ptrType->getPointeeType();
4592 functionType = E->getType();
4593 calleePtr = EmitLValue(E).getPointer();
4595 assert(functionType->isFunctionType());
4598 if (const auto *VD =
4599 dyn_cast_or_null<VarDecl>(E->getReferencedDeclOfCallee()))
4600 GD = GlobalDecl(VD);
4602 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(), GD);
4603 CGCallee callee(calleeInfo, calleePtr);
4607 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
4608 // Comma expressions just emit their LHS then their RHS as an l-value.
4609 if (E->getOpcode() == BO_Comma) {
4610 EmitIgnoredExpr(E->getLHS());
4611 EnsureInsertPoint();
4612 return EmitLValue(E->getRHS());
4615 if (E->getOpcode() == BO_PtrMemD ||
4616 E->getOpcode() == BO_PtrMemI)
4617 return EmitPointerToDataMemberBinaryExpr(E);
4619 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
4621 // Note that in all of these cases, __block variables need the RHS
4622 // evaluated first just in case the variable gets moved by the RHS.
4624 switch (getEvaluationKind(E->getType())) {
4626 switch (E->getLHS()->getType().getObjCLifetime()) {
4627 case Qualifiers::OCL_Strong:
4628 return EmitARCStoreStrong(E, /*ignored*/ false).first;
4630 case Qualifiers::OCL_Autoreleasing:
4631 return EmitARCStoreAutoreleasing(E).first;
4633 // No reason to do any of these differently.
4634 case Qualifiers::OCL_None:
4635 case Qualifiers::OCL_ExplicitNone:
4636 case Qualifiers::OCL_Weak:
4640 RValue RV = EmitAnyExpr(E->getRHS());
4641 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
4643 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc());
4644 EmitStoreThroughLValue(RV, LV);
4649 return EmitComplexAssignmentLValue(E);
4652 return EmitAggExprToLValue(E);
4654 llvm_unreachable("bad evaluation kind");
4657 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
4658 RValue RV = EmitCallExpr(E);
4661 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4662 AlignmentSource::Decl);
4664 assert(E->getCallReturnType(getContext())->isReferenceType() &&
4665 "Can't have a scalar return unless the return type is a "
4668 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4671 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
4672 // FIXME: This shouldn't require another copy.
4673 return EmitAggExprToLValue(E);
4676 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
4677 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
4678 && "binding l-value to type which needs a temporary");
4679 AggValueSlot Slot = CreateAggTemp(E->getType());
4680 EmitCXXConstructExpr(E, Slot);
4681 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4685 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
4686 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType());
4689 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
4690 return Builder.CreateElementBitCast(CGM.GetAddrOfUuidDescriptor(E),
4691 ConvertType(E->getType()));
4694 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
4695 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(),
4696 AlignmentSource::Decl);
4700 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
4701 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4702 Slot.setExternallyDestructed();
4703 EmitAggExpr(E->getSubExpr(), Slot);
4704 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress());
4705 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4708 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
4709 RValue RV = EmitObjCMessageExpr(E);
4712 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4713 AlignmentSource::Decl);
4715 assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
4716 "Can't have a scalar return unless the return type is a "
4719 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4722 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
4724 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector());
4725 return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl);
4728 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
4729 const ObjCIvarDecl *Ivar) {
4730 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
4733 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
4734 llvm::Value *BaseValue,
4735 const ObjCIvarDecl *Ivar,
4736 unsigned CVRQualifiers) {
4737 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
4738 Ivar, CVRQualifiers);
4741 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
4742 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
4743 llvm::Value *BaseValue = nullptr;
4744 const Expr *BaseExpr = E->getBase();
4745 Qualifiers BaseQuals;
4748 BaseValue = EmitScalarExpr(BaseExpr);
4749 ObjectTy = BaseExpr->getType()->getPointeeType();
4750 BaseQuals = ObjectTy.getQualifiers();
4752 LValue BaseLV = EmitLValue(BaseExpr);
4753 BaseValue = BaseLV.getPointer();
4754 ObjectTy = BaseExpr->getType();
4755 BaseQuals = ObjectTy.getQualifiers();
4759 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
4760 BaseQuals.getCVRQualifiers());
4761 setObjCGCLValueClass(getContext(), E, LV);
4765 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
4766 // Can only get l-value for message expression returning aggregate type
4767 RValue RV = EmitAnyExprToTemp(E);
4768 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4769 AlignmentSource::Decl);
4772 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee,
4773 const CallExpr *E, ReturnValueSlot ReturnValue,
4774 llvm::Value *Chain) {
4775 // Get the actual function type. The callee type will always be a pointer to
4776 // function type or a block pointer type.
4777 assert(CalleeType->isFunctionPointerType() &&
4778 "Call must have function pointer type!");
4780 const Decl *TargetDecl =
4781 OrigCallee.getAbstractInfo().getCalleeDecl().getDecl();
4783 CalleeType = getContext().getCanonicalType(CalleeType);
4785 auto PointeeType = cast<PointerType>(CalleeType)->getPointeeType();
4787 CGCallee Callee = OrigCallee;
4789 if (getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function) &&
4790 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4791 if (llvm::Constant *PrefixSig =
4792 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
4793 SanitizerScope SanScope(this);
4794 // Remove any (C++17) exception specifications, to allow calling e.g. a
4795 // noexcept function through a non-noexcept pointer.
4797 getContext().getFunctionTypeWithExceptionSpec(PointeeType, EST_None);
4798 llvm::Constant *FTRTTIConst =
4799 CGM.GetAddrOfRTTIDescriptor(ProtoTy, /*ForEH=*/true);
4800 llvm::Type *PrefixStructTyElems[] = {PrefixSig->getType(), Int32Ty};
4801 llvm::StructType *PrefixStructTy = llvm::StructType::get(
4802 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
4804 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4806 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
4807 CalleePtr, llvm::PointerType::getUnqual(PrefixStructTy));
4808 llvm::Value *CalleeSigPtr =
4809 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 0);
4810 llvm::Value *CalleeSig =
4811 Builder.CreateAlignedLoad(CalleeSigPtr, getIntAlign());
4812 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
4814 llvm::BasicBlock *Cont = createBasicBlock("cont");
4815 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
4816 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
4818 EmitBlock(TypeCheck);
4819 llvm::Value *CalleeRTTIPtr =
4820 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 1);
4821 llvm::Value *CalleeRTTIEncoded =
4822 Builder.CreateAlignedLoad(CalleeRTTIPtr, getPointerAlign());
4823 llvm::Value *CalleeRTTI =
4824 DecodeAddrUsedInPrologue(CalleePtr, CalleeRTTIEncoded);
4825 llvm::Value *CalleeRTTIMatch =
4826 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
4827 llvm::Constant *StaticData[] = {EmitCheckSourceLocation(E->getBeginLoc()),
4828 EmitCheckTypeDescriptor(CalleeType)};
4829 EmitCheck(std::make_pair(CalleeRTTIMatch, SanitizerKind::Function),
4830 SanitizerHandler::FunctionTypeMismatch, StaticData,
4831 {CalleePtr, CalleeRTTI, FTRTTIConst});
4833 Builder.CreateBr(Cont);
4838 const auto *FnType = cast<FunctionType>(PointeeType);
4840 // If we are checking indirect calls and this call is indirect, check that the
4841 // function pointer is a member of the bit set for the function type.
4842 if (SanOpts.has(SanitizerKind::CFIICall) &&
4843 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4844 SanitizerScope SanScope(this);
4845 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
4848 if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers)
4849 MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0));
4851 MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
4853 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD);
4855 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4856 llvm::Value *CastedCallee = Builder.CreateBitCast(CalleePtr, Int8PtrTy);
4857 llvm::Value *TypeTest = Builder.CreateCall(
4858 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CastedCallee, TypeId});
4860 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD);
4861 llvm::Constant *StaticData[] = {
4862 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall),
4863 EmitCheckSourceLocation(E->getBeginLoc()),
4864 EmitCheckTypeDescriptor(QualType(FnType, 0)),
4866 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) {
4867 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId,
4868 CastedCallee, StaticData);
4870 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall),
4871 SanitizerHandler::CFICheckFail, StaticData,
4872 {CastedCallee, llvm::UndefValue::get(IntPtrTy)});
4878 Args.add(RValue::get(Builder.CreateBitCast(Chain, CGM.VoidPtrTy)),
4879 CGM.getContext().VoidPtrTy);
4881 // C++17 requires that we evaluate arguments to a call using assignment syntax
4882 // right-to-left, and that we evaluate arguments to certain other operators
4883 // left-to-right. Note that we allow this to override the order dictated by
4884 // the calling convention on the MS ABI, which means that parameter
4885 // destruction order is not necessarily reverse construction order.
4886 // FIXME: Revisit this based on C++ committee response to unimplementability.
4887 EvaluationOrder Order = EvaluationOrder::Default;
4888 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) {
4889 if (OCE->isAssignmentOp())
4890 Order = EvaluationOrder::ForceRightToLeft;
4892 switch (OCE->getOperator()) {
4894 case OO_GreaterGreater:
4899 Order = EvaluationOrder::ForceLeftToRight;
4907 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(),
4908 E->getDirectCallee(), /*ParamsToSkip*/ 0, Order);
4910 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall(
4911 Args, FnType, /*ChainCall=*/Chain);
4914 // If the expression that denotes the called function has a type
4915 // that does not include a prototype, [the default argument
4916 // promotions are performed]. If the number of arguments does not
4917 // equal the number of parameters, the behavior is undefined. If
4918 // the function is defined with a type that includes a prototype,
4919 // and either the prototype ends with an ellipsis (, ...) or the
4920 // types of the arguments after promotion are not compatible with
4921 // the types of the parameters, the behavior is undefined. If the
4922 // function is defined with a type that does not include a
4923 // prototype, and the types of the arguments after promotion are
4924 // not compatible with those of the parameters after promotion,
4925 // the behavior is undefined [except in some trivial cases].
4926 // That is, in the general case, we should assume that a call
4927 // through an unprototyped function type works like a *non-variadic*
4928 // call. The way we make this work is to cast to the exact type
4929 // of the promoted arguments.
4931 // Chain calls use this same code path to add the invisible chain parameter
4932 // to the function type.
4933 if (isa<FunctionNoProtoType>(FnType) || Chain) {
4934 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
4935 CalleeTy = CalleeTy->getPointerTo();
4937 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4938 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast");
4939 Callee.setFunctionPointer(CalleePtr);
4942 llvm::CallBase *CallOrInvoke = nullptr;
4943 RValue Call = EmitCall(FnInfo, Callee, ReturnValue, Args, &CallOrInvoke,
4946 // Generate function declaration DISuprogram in order to be used
4947 // in debug info about call sites.
4948 if (CGDebugInfo *DI = getDebugInfo()) {
4949 if (auto *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl))
4950 DI->EmitFuncDeclForCallSite(CallOrInvoke, QualType(FnType, 0),
4957 LValue CodeGenFunction::
4958 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
4959 Address BaseAddr = Address::invalid();
4960 if (E->getOpcode() == BO_PtrMemI) {
4961 BaseAddr = EmitPointerWithAlignment(E->getLHS());
4963 BaseAddr = EmitLValue(E->getLHS()).getAddress();
4966 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
4968 const MemberPointerType *MPT
4969 = E->getRHS()->getType()->getAs<MemberPointerType>();
4971 LValueBaseInfo BaseInfo;
4972 TBAAAccessInfo TBAAInfo;
4973 Address MemberAddr =
4974 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo,
4977 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo, TBAAInfo);
4980 /// Given the address of a temporary variable, produce an r-value of
4982 RValue CodeGenFunction::convertTempToRValue(Address addr,
4984 SourceLocation loc) {
4985 LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl);
4986 switch (getEvaluationKind(type)) {
4988 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
4990 return lvalue.asAggregateRValue();
4992 return RValue::get(EmitLoadOfScalar(lvalue, loc));
4994 llvm_unreachable("bad evaluation kind");
4997 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
4998 assert(Val->getType()->isFPOrFPVectorTy());
4999 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
5002 llvm::MDBuilder MDHelper(getLLVMContext());
5003 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
5005 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
5009 struct LValueOrRValue {
5015 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
5016 const PseudoObjectExpr *E,
5018 AggValueSlot slot) {
5019 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
5021 // Find the result expression, if any.
5022 const Expr *resultExpr = E->getResultExpr();
5023 LValueOrRValue result;
5025 for (PseudoObjectExpr::const_semantics_iterator
5026 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
5027 const Expr *semantic = *i;
5029 // If this semantic expression is an opaque value, bind it
5030 // to the result of its source expression.
5031 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
5032 // Skip unique OVEs.
5033 if (ov->isUnique()) {
5034 assert(ov != resultExpr &&
5035 "A unique OVE cannot be used as the result expression");
5039 // If this is the result expression, we may need to evaluate
5040 // directly into the slot.
5041 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
5043 if (ov == resultExpr && ov->isRValue() && !forLValue &&
5044 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
5045 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
5046 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(),
5047 AlignmentSource::Decl);
5048 opaqueData = OVMA::bind(CGF, ov, LV);
5049 result.RV = slot.asRValue();
5051 // Otherwise, emit as normal.
5053 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
5055 // If this is the result, also evaluate the result now.
5056 if (ov == resultExpr) {
5058 result.LV = CGF.EmitLValue(ov);
5060 result.RV = CGF.EmitAnyExpr(ov, slot);
5064 opaques.push_back(opaqueData);
5066 // Otherwise, if the expression is the result, evaluate it
5067 // and remember the result.
5068 } else if (semantic == resultExpr) {
5070 result.LV = CGF.EmitLValue(semantic);
5072 result.RV = CGF.EmitAnyExpr(semantic, slot);
5074 // Otherwise, evaluate the expression in an ignored context.
5076 CGF.EmitIgnoredExpr(semantic);
5080 // Unbind all the opaques now.
5081 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
5082 opaques[i].unbind(CGF);
5087 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
5088 AggValueSlot slot) {
5089 return emitPseudoObjectExpr(*this, E, false, slot).RV;
5092 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
5093 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;