Classes
class	ARCMDKindCache
	A cache of MDKinds used by various ARC optimizations. More...
class	ARCRuntimeEntryPoints
	Declarations for ObjC runtime functions and constants. More...
struct	BottomUpPtrState
class	BundledRetainClaimRVs
class	ObjCARCAA
	Analysis pass providing a never-invalidated alias analysis result. More...
class	ObjCARCAAResult
	This is a simple alias analysis implementation that uses knowledge of ARC constructs to answer queries. More...
class	PtrState
	This class summarizes several per-pointer runtime properties which are propagated through the flow graph. More...
struct	RRInfo
	Unidirectional information about either a retain-decrement-use-release sequence or release-use-decrement-retain reverse sequence. More...
struct	TopDownPtrState

Enumerations
enum class	ARCMDKindID { ImpreciseRelease , CopyOnEscape , NoObjCARCExceptions }
enum class	ARCInstKind { Retain , RetainRV , UnsafeClaimRV , RetainBlock , Release , Autorelease , AutoreleaseRV , AutoreleasepoolPush , AutoreleasepoolPop , NoopCast , FusedRetainAutorelease , FusedRetainAutoreleaseRV , LoadWeakRetained , StoreWeak , InitWeak , LoadWeak , MoveWeak , CopyWeak , DestroyWeak , StoreStrong , IntrinsicUser , CallOrUser , Call , User , None }
	Equivalence classes of instructions in the ARC Model. More...
enum class	ARCRuntimeEntryPointKind { AutoreleaseRV , Release , Retain , RetainBlock , Autorelease , StoreStrong , RetainRV , ClaimRV , UnsafeClaimRV , RetainAutorelease , RetainAutoreleaseRV , AutoreleasePoolPush , AutoreleasePoolPop }
enum	DependenceKind { NeedsPositiveRetainCount , AutoreleasePoolBoundary , CanChangeRetainCount , RetainAutoreleaseDep , RetainAutoreleaseRVDep }
	Defines different dependence kinds among various ARC constructs. More...
enum	Sequence { S_None , S_Retain , S_CanRelease , S_Use , S_Stop , S_MovableRelease }
	A sequence of states that a pointer may go through in which an objc_retain and objc_release are actually needed. More...

Functions
bool	ModuleHasARC (const Module &M)
	Test if the given module looks interesting to run ARC optimization on.
const Value *	GetUnderlyingObjCPtr (const Value *V)
	This is a wrapper around getUnderlyingObject which also knows how to look through objc_retain and objc_autorelease calls, which we know to return their argument verbatim.
const Value *	GetUnderlyingObjCPtrCached (const Value V, DenseMap< const Value , std::pair< WeakVH, WeakTrackingVH > > &Cache)
	A wrapper for GetUnderlyingObjCPtr used for results memoization.
const Value *	GetRCIdentityRoot (const Value *V)
	The RCIdentity root of a value `V` is a dominating value U for which retaining or releasing U is equivalent to retaining or releasing V.
Value *	GetRCIdentityRoot (Value *V)
	Helper which calls const Value GetRCIdentityRoot(const Value V) and just casts away the const of the result.
Value *	GetArgRCIdentityRoot (Value *Inst)
	Assuming the given instruction is one of the special calls such as objc_retain or objc_release, return the RCIdentity root of the argument of the call.
bool	IsNullOrUndef (const Value *V)
bool	IsNoopInstruction (const Instruction *I)
bool	IsPotentialRetainableObjPtr (const Value *Op)
	Test whether the given value is possible a retainable object pointer.
bool	IsPotentialRetainableObjPtr (const Value *Op, AAResults &AA)
ARCInstKind	GetCallSiteClass (const CallBase &CB)
	Helper for GetARCInstKind.
bool	IsObjCIdentifiedObject (const Value *V)
	Return true if this value refers to a distinct and identifiable object.
raw_ostream &	operator<< (raw_ostream &OS, const ARCInstKind Class)
bool	IsUser (ARCInstKind Class)
	Test if the given class is a kind of user.
bool	IsRetain (ARCInstKind Class)
	Test if the given class is objc_retain or equivalent.
bool	IsAutorelease (ARCInstKind Class)
	Test if the given class is objc_autorelease or equivalent.
bool	IsForwarding (ARCInstKind Class)
	Test if the given class represents instructions which return their argument verbatim.
bool	IsNoopOnNull (ARCInstKind Class)
	Test if the given class represents instructions which do nothing if passed a null pointer.
bool	IsNoopOnGlobal (ARCInstKind Class)
	Test if the given class represents instructions which do nothing if passed a global variable.
bool	IsAlwaysTail (ARCInstKind Class)
	Test if the given class represents instructions which are always safe to mark with the "tail" keyword.
bool	IsNeverTail (ARCInstKind Class)
	Test if the given class represents instructions which are never safe to mark with the "tail" keyword.
bool	IsNoThrow (ARCInstKind Class)
	Test if the given class represents instructions which are always safe to mark with the nounwind attribute.
bool	CanInterruptRV (ARCInstKind Class)
	Test whether the given instruction can autorelease any pointer or cause an autoreleasepool pop.
ARCInstKind	GetFunctionClass (const Function *F)
	Determine if F is one of the special known Functions.
ARCInstKind	GetBasicARCInstKind (const Value *V)
	Determine which objc runtime call instruction class V belongs to.
ARCInstKind	GetARCInstKind (const Value *V)
	Map V to its ARCInstKind equivalence class.
bool	CanDecrementRefCount (ARCInstKind Kind)
	Returns false if conservatively we can prove that any instruction mapped to this kind can not decrement ref counts.
const char *	getRVMarkerModuleFlagStr ()
bool	hasAttachedCallOpBundle (const CallBase *CB)
std::optional< Function * >	getAttachedARCFunction (const CallBase *CB)
	This function returns operand bundle clang_arc_attachedcall's argument, which is the address of the ARC runtime function.
bool	attachedCallOpBundleNeedsMarker (const CallBase *CB)
	This function determines whether the clang_arc_attachedcall should be emitted with or without the marker.
bool	isRetainOrClaimRV (ARCInstKind Kind)
	Check whether the function is retainRV/unsafeClaimRV.
ARCInstKind	getAttachedARCFunctionKind (const CallBase *CB)
	This function returns the ARCInstKind of the function attached to operand bundle clang_arc_attachedcall.
llvm::Instruction *	findSingleDependency (DependenceKind Flavor, const Value Arg, BasicBlock StartBB, Instruction *StartInst, ProvenanceAnalysis &PA)
	Find dependent instructions.
bool	Depends (DependenceKind Flavor, Instruction Inst, const Value Arg, ProvenanceAnalysis &PA)
	Test if there can be dependencies on Inst through Arg.
bool	CanUse (const Instruction Inst, const Value Ptr, ProvenanceAnalysis &PA, ARCInstKind Class)
	Test whether the given instruction can "use" the given pointer's object in a way that requires the reference count to be positive.
bool	CanAlterRefCount (const Instruction Inst, const Value Ptr, ProvenanceAnalysis &PA, ARCInstKind Class)
	Test whether the given instruction can result in a reference count modification (positive or negative) for the pointer's object.
bool	CanDecrementRefCount (const Instruction Inst, const Value Ptr, ProvenanceAnalysis &PA, ARCInstKind Class)
	Returns true if we can not conservatively prove that Inst can not decrement the reference count of Ptr.
static bool	CanDecrementRefCount (const Instruction Inst, const Value Ptr, ProvenanceAnalysis &PA)
static void	EraseInstruction (Instruction *CI)
	Erase the given instruction.
static const Instruction *	getreturnRVOperand (const Instruction &Inst, ARCInstKind Class)
	If Inst is a ReturnRV and its operand is a call or invoke, return the operand.
template<class PHINodeTy, class VectorTy>
void	getEquivalentPHIs (PHINodeTy &PN, VectorTy &PHIList)
	Return the list of PHI nodes that are equivalent to PN.
static MDString *	getRVInstMarker (Module &M)
CallInst *	createCallInstWithColors (FunctionCallee Func, ArrayRef< Value * > Args, const Twine &NameStr, BasicBlock::iterator InsertBefore, const DenseMap< BasicBlock *, ColorVector > &BlockColors)
	Create a call instruction with the correct funclet token.
raw_ostream &	operator<< (raw_ostream &OS, const Sequence S) LLVM_ATTRIBUTE_UNUSED

Variables
bool	EnableARCOpts
	A handy option to enable/disable all ARC Optimizations.

Enumeration Type Documentation

◆ ARCInstKind

enum class llvm::objcarc::ARCInstKind

strong

Equivalence classes of instructions in the ARC Model.

Since we do not have "instructions" to represent ARC concepts in LLVM IR, we instead operate on equivalence classes of instructions.

TODO: This should be split into two enums: a runtime entry point enum (possibly united with the ARCRuntimeEntrypoint class) and an enum that deals with effects of instructions in the ARC model (which would handle the notion of a User or CallOrUser).

Enumerator
Retain	objc_retain
RetainRV	objc_retainAutoreleasedReturnValue
UnsafeClaimRV	objc_unsafeClaimAutoreleasedReturnValue
RetainBlock	objc_retainBlock
Release	objc_release
Autorelease	objc_autorelease
AutoreleaseRV	objc_autoreleaseReturnValue
AutoreleasepoolPush	objc_autoreleasePoolPush
AutoreleasepoolPop	objc_autoreleasePoolPop
NoopCast	objc_retainedObject, etc.
FusedRetainAutorelease	objc_retainAutorelease
FusedRetainAutoreleaseRV	objc_retainAutoreleaseReturnValue
LoadWeakRetained	objc_loadWeakRetained (primitive)
StoreWeak	objc_storeWeak (primitive)
InitWeak	objc_initWeak (derived)
LoadWeak	objc_loadWeak (derived)
MoveWeak	objc_moveWeak (derived)
CopyWeak	objc_copyWeak (derived)
DestroyWeak	objc_destroyWeak (derived)
StoreStrong	objc_storeStrong (derived)
IntrinsicUser	llvm.objc.clang.arc.use
CallOrUser	could call objc_release and/or "use" pointers
Call	could call objc_release
User	could "use" a pointer
None	anything that is inert from an ARC perspective.

Definition at line 28 of file ObjCARCInstKind.h.

◆ ARCMDKindID

enum class llvm::objcarc::ARCMDKindID

strong

Enumerator
ImpreciseRelease
CopyOnEscape
NoObjCARCExceptions

Definition at line 229 of file ObjCARCAnalysisUtils.h.

◆ ARCRuntimeEntryPointKind

enum class llvm::objcarc::ARCRuntimeEntryPointKind

strong

Enumerator
AutoreleaseRV
Release
Retain
RetainBlock
Autorelease
StoreStrong
RetainRV
ClaimRV
UnsafeClaimRV
RetainAutorelease
RetainAutoreleaseRV
AutoreleasePoolPush
AutoreleasePoolPop

Definition at line 37 of file ARCRuntimeEntryPoints.h.

◆ DependenceKind

enum llvm::objcarc::DependenceKind

Defines different dependence kinds among various ARC constructs.

There are several kinds of dependence-like concepts in use here.

Enumerator
NeedsPositiveRetainCount
AutoreleasePoolBoundary
CanChangeRetainCount
RetainAutoreleaseDep	Blocks objc_retainAutorelease.
RetainAutoreleaseRVDep	Blocks objc_retainAutoreleaseReturnValue.

Definition at line 43 of file DependencyAnalysis.h.

◆ Sequence

enum llvm::objcarc::Sequence

A sequence of states that a pointer may go through in which an objc_retain and objc_release are actually needed.

Enumerator
S_None
S_Retain	objc_retain(x).
S_CanRelease	foo(x) – x could possibly see a ref count decrement.
S_Use	any use of x.
S_Stop	code motion is stopped.
S_MovableRelease	objc_release(x), !clang.imprecise_release.

Definition at line 41 of file PtrState.h.

Function Documentation

◆ attachedCallOpBundleNeedsMarker()

bool llvm::objcarc::attachedCallOpBundleNeedsMarker ( const CallBase * CB )

inline

This function determines whether the clang_arc_attachedcall should be emitted with or without the marker.

Concretely, this is the difference between: objc_retainAutoreleasedReturnValue and objc_claimAutoreleasedReturnValue retainRV (and unsafeClaimRV) requires a marker, but claimRV does not.

Definition at line 58 of file ObjCARCUtil.h.

References getAttachedARCFunction().

Referenced by llvm::AArch64CallLowering::lowerCall().

◆ CanAlterRefCount()

bool llvm::objcarc::CanAlterRefCount	(	const Instruction *	Inst,
		const Value *	Ptr,
		ProvenanceAnalysis &	PA,
		ARCInstKind	Class )

Test whether the given instruction can result in a reference count modification (positive or negative) for the pointer's object.

Definition at line 35 of file DependencyAnalysis.cpp.

References Autorelease, AutoreleaseRV, Call, llvm::cast(), ProvenanceAnalysis::getAA(), llvm::AAResults::getMemoryEffects(), IntrinsicUser, IsPotentialRetainableObjPtr(), llvm::MemoryEffectsBase< LocationEnum >::onlyAccessesArgPointees(), llvm::MemoryEffectsBase< LocationEnum >::onlyReadsMemory(), Ptr, ProvenanceAnalysis::related(), and User.

Referenced by CanDecrementRefCount(), and Depends().

◆ CanDecrementRefCount() [1/3]

bool llvm::objcarc::CanDecrementRefCount ( ARCInstKind Kind )

Returns false if conservatively we can prove that any instruction mapped to this kind can not decrement ref counts.

Returns true otherwise.

Definition at line 667 of file ObjCARCInstKind.cpp.

References Autorelease, AutoreleasepoolPop, AutoreleasepoolPush, AutoreleaseRV, Call, CallOrUser, CopyWeak, DestroyWeak, FusedRetainAutorelease, FusedRetainAutoreleaseRV, InitWeak, IntrinsicUser, llvm_unreachable, LoadWeak, LoadWeakRetained, MoveWeak, None, NoopCast, Release, Retain, RetainBlock, RetainRV, StoreStrong, StoreWeak, UnsafeClaimRV, and User.

Referenced by CanDecrementRefCount(), CanDecrementRefCount(), findRetainForStoreStrongContraction(), llvm::objcarc::BottomUpPtrState::HandlePotentialAlterRefCount(), and llvm::objcarc::TopDownPtrState::HandlePotentialAlterRefCount().

◆ CanDecrementRefCount() [2/3]

bool llvm::objcarc::CanDecrementRefCount	(	const Instruction *	Inst,
		const Value *	Ptr,
		ProvenanceAnalysis &	PA )

inlinestatic

Definition at line 77 of file DependencyAnalysis.h.

References CanDecrementRefCount(), GetARCInstKind(), and Ptr.

◆ CanDecrementRefCount() [3/3]

bool llvm::objcarc::CanDecrementRefCount	(	const Instruction *	Inst,
		const Value *	Ptr,
		ProvenanceAnalysis &	PA,
		ARCInstKind	Class )

Returns true if we can not conservatively prove that Inst can not decrement the reference count of Ptr.

Returns false if we can.

Definition at line 66 of file DependencyAnalysis.cpp.

References CanAlterRefCount(), CanDecrementRefCount(), and Ptr.

◆ CanInterruptRV()

bool llvm::objcarc::CanInterruptRV ( ARCInstKind Class )

Test whether the given instruction can autorelease any pointer or cause an autoreleasepool pop.

This means that it could interrupt the RV optimization.

Definition at line 634 of file ObjCARCInstKind.cpp.

References Autorelease, AutoreleasepoolPop, AutoreleasepoolPush, AutoreleaseRV, Call, CallOrUser, CopyWeak, DestroyWeak, FusedRetainAutorelease, FusedRetainAutoreleaseRV, InitWeak, IntrinsicUser, llvm_unreachable, LoadWeak, LoadWeakRetained, MoveWeak, None, NoopCast, Release, Retain, RetainBlock, RetainRV, StoreStrong, StoreWeak, UnsafeClaimRV, and User.

Referenced by Depends().

◆ CanUse()

bool llvm::objcarc::CanUse	(	const Instruction *	Inst,
		const Value *	Ptr,
		ProvenanceAnalysis &	PA,
		ARCInstKind	Class )

Test whether the given instruction can "use" the given pointer's object in a way that requires the reference count to be positive.

Definition at line 80 of file DependencyAnalysis.cpp.

References Call, llvm::dyn_cast(), ProvenanceAnalysis::getAA(), GetUnderlyingObjCPtr(), IsPotentialRetainableObjPtr(), llvm::User::operands(), Ptr, and ProvenanceAnalysis::related().

Referenced by Depends(), findSafeStoreForStoreStrongContraction(), llvm::objcarc::BottomUpPtrState::HandlePotentialUse(), and llvm::objcarc::TopDownPtrState::HandlePotentialUse().

◆ createCallInstWithColors()

CallInst * llvm::objcarc::createCallInstWithColors	(	FunctionCallee	Func,
		ArrayRef< Value * >	Args,
		const Twine &	NameStr,
		BasicBlock::iterator	InsertBefore,
		const DenseMap< BasicBlock *, ColorVector > &	BlockColors )

Create a call instruction with the correct funclet token.

This should be called instead of calling CallInst::Create directly unless the call is going to be removed from the IR before WinEHPrepare.

Definition at line 24 of file ObjCARC.cpp.

References assert(), llvm::CallInst::Create(), llvm::SmallVectorImpl< T >::emplace_back(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::empty(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::find(), llvm::TinyPtrVector< EltTy >::front(), llvm::BasicBlock::getFirstNonPHIIt(), and llvm::TinyPtrVector< EltTy >::size().

Referenced by llvm::objcarc::BundledRetainClaimRVs::insertRVCallWithColors().

◆ Depends()

bool llvm::objcarc::Depends	(	DependenceKind	Flavor,
		Instruction *	Inst,
		const Value *	Arg,
		ProvenanceAnalysis &	PA )

Test if there can be dependencies on Inst through Arg.

This function only tests dependencies relevant for removing pairs of calls.

Definition at line 122 of file DependencyAnalysis.cpp.

References AutoreleasePoolBoundary, AutoreleasepoolPop, AutoreleasepoolPush, CanAlterRefCount(), CanChangeRetainCount, CanInterruptRV(), CanUse(), GetARCInstKind(), GetArgRCIdentityRoot(), GetBasicARCInstKind(), llvm_unreachable, NeedsPositiveRetainCount, None, Retain, RetainAutoreleaseDep, RetainAutoreleaseRVDep, and RetainRV.

Referenced by findDependencies().

◆ EraseInstruction()

void llvm::objcarc::EraseInstruction ( Instruction * CI )

inlinestatic

Erase the given instruction.

Many ObjC calls return their argument verbatim, so if it's such a call and the return value has users, replace them with the argument value.

Definition at line 40 of file ObjCARC.h.

References assert(), llvm::cast(), llvm::Instruction::eraseFromParent(), GetBasicARCInstKind(), IsForwarding(), IsNoopOnNull(), IsNullOrUndef(), llvm::RecursivelyDeleteTriviallyDeadInstructions(), llvm::Value::replaceAllUsesWith(), llvm::Value::stripPointerCasts(), and llvm::Value::use_empty().

Referenced by llvm::objcarc::BundledRetainClaimRVs::eraseInst(), and llvm::objcarc::BundledRetainClaimRVs::~BundledRetainClaimRVs().

◆ findSingleDependency()

llvm::Instruction * llvm::objcarc::findSingleDependency	(	DependenceKind	Flavor,
		const Value *	Arg,
		BasicBlock *	StartBB,
		Instruction *	StartInst,
		ProvenanceAnalysis &	PA )

Find dependent instructions.

If there is exactly one dependent instruction, return it. Otherwise, return null.

Definition at line 255 of file DependencyAnalysis.cpp.

References llvm::SmallPtrSetImpl< PtrType >::begin(), findDependencies(), and llvm::SmallPtrSetImplBase::size().

Referenced by FindPredecessorRetainWithSafePath(), and HasSafePathToPredecessorCall().

◆ GetARCInstKind()

ARCInstKind llvm::objcarc::GetARCInstKind ( const Value * V )

Map V to its ARCInstKind equivalence class.

Determine what kind of construct V is.

Definition at line 213 of file ObjCARCInstKind.cpp.

References CallOrUser, llvm::cast(), llvm::dyn_cast(), F, llvm::CallBase::getCalledFunction(), GetCallSiteClass(), GetFunctionClass(), I, isInertIntrinsic(), IsPotentialRetainableObjPtr(), isUseOnlyIntrinsic(), None, and User.

Referenced by CanDecrementRefCount(), and Depends().

◆ GetArgRCIdentityRoot()

Value * llvm::objcarc::GetArgRCIdentityRoot ( Value * Inst )

inline

Assuming the given instruction is one of the special calls such as objc_retain or objc_release, return the RCIdentity root of the argument of the call.

Definition at line 139 of file ObjCARCAnalysisUtils.h.

References llvm::cast(), and GetRCIdentityRoot().

Referenced by Depends(), FindPredecessorRetainWithSafePath(), and findRetainForStoreStrongContraction().

◆ getAttachedARCFunction()

std::optional< Function * > llvm::objcarc::getAttachedARCFunction ( const CallBase * CB )

inline

This function returns operand bundle clang_arc_attachedcall's argument, which is the address of the ARC runtime function.

Definition at line 43 of file ObjCARCUtil.h.

References B(), llvm::cast(), llvm::CallBase::getOperandBundle(), and llvm::LLVMContext::OB_clang_arc_attachedcall.

Referenced by attachedCallOpBundleNeedsMarker(), getAttachedARCFunctionKind(), inlineRetainOrClaimRVCalls(), llvm::objcarc::BundledRetainClaimRVs::insertRVCallWithColors(), llvm::AArch64CallLowering::lowerCall(), and lowerObjCCall().

◆ getAttachedARCFunctionKind()

ARCInstKind llvm::objcarc::getAttachedARCFunctionKind ( const CallBase * CB )

inline

This function returns the ARCInstKind of the function attached to operand bundle clang_arc_attachedcall.

It returns std::nullopt if the call doesn't have the operand bundle or the operand is null. Otherwise it returns either RetainRV or UnsafeClaimRV.

Definition at line 75 of file ObjCARCUtil.h.

References assert(), getAttachedARCFunction(), GetFunctionClass(), isRetainOrClaimRV(), and None.

Referenced by llvm::InlineFunctionImpl().

◆ GetBasicARCInstKind()

ARCInstKind llvm::objcarc::GetBasicARCInstKind ( const Value * V )

inline

Determine which objc runtime call instruction class V belongs to.

This is similar to GetARCInstKind except that it only detects objc runtime calls. This allows it to be faster.

Definition at line 104 of file ObjCARCInstKind.h.

References CallOrUser, llvm::dyn_cast(), F, GetFunctionClass(), llvm::isa(), and User.

Referenced by Depends(), EraseInstruction(), FindPredecessorRetainWithSafePath(), findRetainForStoreStrongContraction(), findSafeStoreForStoreStrongContraction(), FindSingleUseIdentifiedObject(), llvm::objcarc::ObjCARCAAResult::getModRefInfo(), GetRCIdentityRoot(), GetUnderlyingObjCPtr(), llvm::objcarc::BottomUpPtrState::HandlePotentialUse(), HasSafePathToPredecessorCall(), if(), and MayAutorelease().

◆ GetCallSiteClass()

ARCInstKind llvm::objcarc::GetCallSiteClass ( const CallBase & CB )

inline

Helper for GetARCInstKind.

Determines what kind of construct CS is.

Definition at line 181 of file ObjCARCAnalysisUtils.h.

References llvm::CallBase::args(), Call, CallOrUser, IsPotentialRetainableObjPtr(), None, llvm::CallBase::onlyReadsMemory(), and User.

Referenced by GetARCInstKind().

◆ getEquivalentPHIs()

template<class PHINodeTy, class VectorTy>

void llvm::objcarc::getEquivalentPHIs	(	PHINodeTy &	PN,
		VectorTy &	PHIList )

Return the list of PHI nodes that are equivalent to PN.

Definition at line 75 of file ObjCARC.h.

References E(), I, and P.

◆ GetFunctionClass()

ARCInstKind llvm::objcarc::GetFunctionClass ( const Function * F )

Determine if F is one of the special known Functions.

If it isn't, return ARCInstKind::CallOrUser.

Definition at line 85 of file ObjCARCInstKind.cpp.

References Autorelease, AutoreleasepoolPop, AutoreleasepoolPush, AutoreleaseRV, CallOrUser, CopyWeak, DestroyWeak, F, FusedRetainAutorelease, FusedRetainAutoreleaseRV, InitWeak, IntrinsicUser, LoadWeak, LoadWeakRetained, MoveWeak, None, NoopCast, Release, Retain, RetainBlock, RetainRV, StoreStrong, StoreWeak, UnsafeClaimRV, and User.

Referenced by GetARCInstKind(), getAttachedARCFunctionKind(), GetBasicARCInstKind(), llvm::objcarc::ObjCARCAAResult::getMemoryEffects(), and getOverridingTailCallKind().

◆ GetRCIdentityRoot() [1/2]

const Value * llvm::objcarc::GetRCIdentityRoot ( const Value * V )

inline

The RCIdentity root of a value V is a dominating value U for which retaining or releasing U is equivalent to retaining or releasing V.

In other words, ARC operations on V are equivalent to ARC operations on U.

We use this in the ARC optimizer to make it easier to match up ARC operations by always mapping ARC operations to RCIdentityRoots instead of pointers themselves.

The two ways that we see RCIdentical values in ObjC are via:

PointerCasts
Forwarding Calls that return their argument verbatim.

Thus this function strips off pointer casts and forwarding calls. NOTE This implies that two RCIdentical values must alias.

Definition at line 118 of file ObjCARCAnalysisUtils.h.

References llvm::cast(), GetBasicARCInstKind(), and IsForwarding().

Referenced by llvm::objcarc::ObjCARCAAResult::alias(), collectReleaseInsertPts(), FindSingleUseIdentifiedObject(), GetArgRCIdentityRoot(), llvm::objcarc::ObjCARCAAResult::getModRefInfoMask(), GetRCIdentityRoot(), inlineRetainOrClaimRVCalls(), and IsObjCIdentifiedObject().

◆ GetRCIdentityRoot() [2/2]

Value * llvm::objcarc::GetRCIdentityRoot ( Value * V )

inline

Helper which calls const Value *GetRCIdentityRoot(const Value *V) and just casts away the const of the result.

For documentation about what an RCIdentityRoot (and by extension GetRCIdentityRoot is) look at that function.

Definition at line 132 of file ObjCARCAnalysisUtils.h.

References GetRCIdentityRoot().

◆ getreturnRVOperand()

const Instruction * llvm::objcarc::getreturnRVOperand	(	const Instruction &	Inst,
		ARCInstKind	Class )

inlinestatic

If Inst is a ReturnRV and its operand is a call or invoke, return the operand.

Otherwise return null.

Definition at line 62 of file ObjCARC.h.

References llvm::CallingConv::C, llvm::dyn_cast(), llvm::User::getOperand(), RetainRV, and llvm::Value::stripPointerCasts().

Referenced by llvm::objcarc::BottomUpPtrState::HandlePotentialUse().

◆ getRVInstMarker()

MDString * llvm::objcarc::getRVInstMarker ( Module & M )

inlinestatic

Definition at line 93 of file ObjCARC.h.

References llvm::dyn_cast_or_null(), and getRVMarkerModuleFlagStr().

◆ getRVMarkerModuleFlagStr()

const char * llvm::objcarc::getRVMarkerModuleFlagStr ( )

inline

Definition at line 25 of file ObjCARCUtil.h.

Referenced by getRVInstMarker().

◆ GetUnderlyingObjCPtr()

const Value * llvm::objcarc::GetUnderlyingObjCPtr ( const Value * V )

inline

This is a wrapper around getUnderlyingObject which also knows how to look through objc_retain and objc_autorelease calls, which we know to return their argument verbatim.

Definition at line 77 of file ObjCARCAnalysisUtils.h.

References llvm::cast(), GetBasicARCInstKind(), llvm::getUnderlyingObject(), and IsForwarding().

Referenced by llvm::objcarc::ObjCARCAAResult::alias(), CanUse(), llvm::objcarc::ObjCARCAAResult::getModRefInfoMask(), and GetUnderlyingObjCPtrCached().

◆ GetUnderlyingObjCPtrCached()

const Value * llvm::objcarc::GetUnderlyingObjCPtrCached	(	const Value *	V,
		DenseMap< const Value *, std::pair< WeakVH, WeakTrackingVH > > &	Cache )

inline

A wrapper for GetUnderlyingObjCPtr used for results memoization.

Definition at line 89 of file ObjCARCAnalysisUtils.h.

References GetUnderlyingObjCPtr().

Referenced by ProvenanceAnalysis::related().

◆ hasAttachedCallOpBundle()

bool llvm::objcarc::hasAttachedCallOpBundle ( const CallBase * CB )

inline

Definition at line 29 of file ObjCARCUtil.h.

References llvm::CallBase::getFunctionType(), llvm::CallBase::getOperandBundle(), llvm::FunctionType::getReturnType(), llvm::Type::isVoidTy(), and llvm::LLVMContext::OB_clang_arc_attachedcall.

Referenced by llvm::objcarc::BottomUpPtrState::HandlePotentialUse(), inlineRetainOrClaimRVCalls(), llvm::objcarc::BundledRetainClaimRVs::insertAfterInvokes(), and llvm::AArch64CallLowering::lowerCall().

◆ IsAlwaysTail()

bool llvm::objcarc::IsAlwaysTail ( ARCInstKind Class )

Test if the given class represents instructions which are always safe to mark with the "tail" keyword.

Definition at line 520 of file ObjCARCInstKind.cpp.

References Autorelease, AutoreleasepoolPop, AutoreleasepoolPush, AutoreleaseRV, Call, CallOrUser, CopyWeak, DestroyWeak, FusedRetainAutorelease, FusedRetainAutoreleaseRV, InitWeak, IntrinsicUser, llvm_unreachable, LoadWeak, LoadWeakRetained, MoveWeak, None, NoopCast, Release, Retain, RetainBlock, RetainRV, StoreStrong, StoreWeak, UnsafeClaimRV, and User.

Referenced by getOverridingTailCallKind().

◆ IsAutorelease()

bool llvm::objcarc::IsAutorelease ( ARCInstKind Class )

Test if the given class is objc_autorelease or equivalent.

Definition at line 380 of file ObjCARCInstKind.cpp.

References Autorelease, AutoreleasepoolPop, AutoreleasepoolPush, AutoreleaseRV, Call, CallOrUser, CopyWeak, DestroyWeak, FusedRetainAutorelease, FusedRetainAutoreleaseRV, InitWeak, IntrinsicUser, llvm_unreachable, LoadWeak, LoadWeakRetained, MoveWeak, None, NoopCast, Release, Retain, RetainBlock, RetainRV, StoreStrong, StoreWeak, UnsafeClaimRV, and User.

◆ IsForwarding()

bool llvm::objcarc::IsForwarding ( ARCInstKind Class )

Test if the given class represents instructions which return their argument verbatim.

Definition at line 415 of file ObjCARCInstKind.cpp.

References Autorelease, AutoreleasepoolPop, AutoreleasepoolPush, AutoreleaseRV, Call, CallOrUser, CopyWeak, DestroyWeak, FusedRetainAutorelease, FusedRetainAutoreleaseRV, InitWeak, IntrinsicUser, llvm_unreachable, LoadWeak, LoadWeakRetained, MoveWeak, None, NoopCast, Release, Retain, RetainBlock, RetainRV, StoreStrong, StoreWeak, UnsafeClaimRV, and User.

Referenced by EraseInstruction(), FindSingleUseIdentifiedObject(), GetRCIdentityRoot(), and GetUnderlyingObjCPtr().

◆ IsNeverTail()

bool llvm::objcarc::IsNeverTail ( ARCInstKind Class )

Test if the given class represents instructions which are never safe to mark with the "tail" keyword.

It is never safe to tail call objc_autorelease since by tail calling objc_autorelease: fast autoreleasing causing our object to be potentially reclaimed from the autorelease pool which violates the semantics of __autoreleasing types in ARC.

Definition at line 556 of file ObjCARCInstKind.cpp.

References Autorelease, AutoreleasepoolPop, AutoreleasepoolPush, AutoreleaseRV, Call, CallOrUser, CopyWeak, DestroyWeak, FusedRetainAutorelease, FusedRetainAutoreleaseRV, InitWeak, IntrinsicUser, llvm_unreachable, LoadWeak, LoadWeakRetained, MoveWeak, None, NoopCast, Release, Retain, RetainBlock, RetainRV, StoreStrong, StoreWeak, UnsafeClaimRV, and User.