Namespaces
	llvm
	This class represents lattice values for constants.

Functions
	STATISTIC (NumNoops, "Number of no-op objc calls eliminated")

	STATISTIC (NumPartialNoops, "Number of partially no-op objc calls eliminated")

	STATISTIC (NumAutoreleases,"Number of autoreleases converted to releases")

	STATISTIC (NumRets, "Number of return value forwarding " "retain+autoreleases eliminated")

	STATISTIC (NumRRs, "Number of retain+release paths eliminated")

	STATISTIC (NumPeeps, "Number of calls peephole-optimized")

	STATISTIC (NumRetainsBeforeOpt, "Number of retains before optimization")

	STATISTIC (NumReleasesBeforeOpt, "Number of releases before optimization")

	STATISTIC (NumRetainsAfterOpt, "Number of retains after optimization")

	STATISTIC (NumReleasesAfterOpt, "Number of releases after optimization")

	INITIALIZE_PASS_BEGIN (ObjCARCOpt, "objc-arc", "ObjC ARC optimization", false, false) INITIALIZE_PASS_END(ObjCARCOpt

static void	CheckForUseCFGHazard (const Sequence SuccSSeq, const bool SuccSRRIKnownSafe, TopDownPtrState &S, bool &SomeSuccHasSame, bool &AllSuccsHaveSame, bool &NotAllSeqEqualButKnownSafe, bool &ShouldContinue)
	If we have a top down pointer in the S_Use state, make sure that there are no CFG hazards by checking the states of various bottom up pointers. More...

static void	CheckForCanReleaseCFGHazard (const Sequence SuccSSeq, const bool SuccSRRIKnownSafe, TopDownPtrState &S, bool &SomeSuccHasSame, bool &AllSuccsHaveSame, bool &NotAllSeqEqualButKnownSafe)
	If we have a Top Down pointer in the S_CanRelease state, make sure that there are no CFG hazards by checking the states of various bottom up pointers. More...

static void	ComputePostOrders (Function &F, SmallVectorImpl< BasicBlock > &PostOrder, SmallVectorImpl< BasicBlock > &ReverseCFGPostOrder, unsigned NoObjCARCExceptionsMDKind, DenseMap< const BasicBlock *, BBState > &BBStates)

static bool	HasSafePathToPredecessorCall (const Value Arg, Instruction Retain, SmallPtrSetImpl< Instruction > &DepInsts, SmallPtrSetImpl< const BasicBlock > &Visited, ProvenanceAnalysis &PA)
	Check if there is a dependent call earlier that does not have anything in between the Retain and the call that can affect the reference count of their shared pointer argument. More...

static CallInst *	FindPredecessorRetainWithSafePath (const Value Arg, BasicBlock BB, Instruction Autorelease, SmallPtrSetImpl< Instruction > &DepInsts, SmallPtrSetImpl< const BasicBlock *> &Visited, ProvenanceAnalysis &PA)
	Find a dependent retain that precedes the given autorelease for which there is nothing in between the two instructions that can affect the ref count of Arg. More...

static CallInst *	FindPredecessorAutoreleaseWithSafePath (const Value Arg, BasicBlock BB, ReturnInst Ret, SmallPtrSetImpl< Instruction > &DepInsts, SmallPtrSetImpl< const BasicBlock *> &V, ProvenanceAnalysis &PA)
	Look for an ``autorelease'' instruction dependent on Arg such that there are no instructions dependent on Arg that need a positive ref count in between the autorelease and the ret. More...

raw_ostream &	llvm::operator<< (raw_ostream &OS, BBState &BBState) LLVM_ATTRIBUTE_UNUSED

Pass *	llvm::createObjCARCOptPass ()

Variables
objc	arc

objc ObjC ARC	optimization

objc ObjC ARC	false

static const unsigned	BBState::OverflowOccurredValue = 0xffffffff

static char	ObjCARCOpt::ID = 0

Detailed Description

Function Documentation

◆ CheckForCanReleaseCFGHazard()

static void CheckForCanReleaseCFGHazard	(	const Sequence	SuccSSeq,
		const bool	SuccSRRIKnownSafe,
		TopDownPtrState &	S,
		bool &	SomeSuccHasSame,
		bool &	AllSuccsHaveSame,
		bool &	NotAllSeqEqualButKnownSafe
	)

static

If we have a Top Down pointer in the S_CanRelease state, make sure that there are no CFG hazards by checking the states of various bottom up pointers.

Definition at line 1048 of file ObjCARCOpts.cpp.

References Arg, assert(), llvm::objcarc::AutoreleasepoolPop, llvm::objcarc::AutoreleasepoolPush, llvm::BasicBlock::back(), llvm::BasicBlock::begin(), CheckForUseCFGHazard(), llvm::objcarc::PtrState::ClearSequenceProgress(), llvm::dbgs(), E, llvm::DenseMapBase< DenseMap< KeyT, ValueT, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::BasicBlock::end(), llvm::DenseMapBase< DenseMap< KeyT, ValueT, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::find(), llvm::objcarc::GetARCInstKind(), llvm::objcarc::GetArgRCIdentityRoot(), llvm::objcarc::PtrState::GetRRInfo(), llvm::objcarc::PtrState::GetSeq(), llvm::objcarc::BottomUpPtrState::HandlePotentialAlterRefCount(), llvm::objcarc::TopDownPtrState::HandlePotentialAlterRefCount(), llvm::objcarc::BottomUpPtrState::HandlePotentialUse(), llvm::objcarc::TopDownPtrState::HandlePotentialUse(), I, llvm::objcarc::BottomUpPtrState::InitBottomUp(), llvm::objcarc::TopDownPtrState::InitTopDown(), llvm::objcarc::PtrState::IsKnownSafe(), LLVM_DEBUG, llvm_unreachable, llvm::objcarc::TopDownPtrState::MatchWithRelease(), llvm::objcarc::BottomUpPtrState::MatchWithRetain(), MI, llvm::objcarc::None, llvm::objcarc::Release, llvm::objcarc::Retain, llvm::objcarc::RetainBlock, llvm::objcarc::RetainRV, llvm::objcarc::S_CanRelease, llvm::objcarc::S_MovableRelease, llvm::objcarc::S_None, llvm::objcarc::S_Release, llvm::objcarc::S_Retain, llvm::objcarc::S_Stop, llvm::objcarc::S_Use, llvm::objcarc::PtrState::SetCFGHazardAfflicted(), SI, and llvm::successors().

◆ CheckForUseCFGHazard()

static void CheckForUseCFGHazard	(	const Sequence	SuccSSeq,
		const bool	SuccSRRIKnownSafe,
		TopDownPtrState &	S,
		bool &	SomeSuccHasSame,
		bool &	AllSuccsHaveSame,
		bool &	NotAllSeqEqualButKnownSafe,
		bool &	ShouldContinue
	)

static

If we have a top down pointer in the S_Use state, make sure that there are no CFG hazards by checking the states of various bottom up pointers.

Definition at line 1010 of file ObjCARCOpts.cpp.

References llvm::objcarc::PtrState::ClearSequenceProgress(), llvm::objcarc::PtrState::IsKnownSafe(), llvm_unreachable, llvm::objcarc::S_CanRelease, llvm::objcarc::S_MovableRelease, llvm::objcarc::S_None, llvm::objcarc::S_Release, llvm::objcarc::S_Retain, llvm::objcarc::S_Stop, llvm::objcarc::S_Use, and llvm::objcarc::PtrState::SetCFGHazardAfflicted().

Referenced by CheckForCanReleaseCFGHazard().

◆ ComputePostOrders()

static void ComputePostOrders	(	Function &	F,
		SmallVectorImpl< BasicBlock *> &	PostOrder,
		SmallVectorImpl< BasicBlock *> &	ReverseCFGPostOrder,
		unsigned	NoObjCARCExceptionsMDKind,
		DenseMap< const BasicBlock *, BBState > &	BBStates
	)

static

The visited set, for doing DFS walks.

Definition at line 1408 of file ObjCARCOpts.cpp.

References Arg, assert(), llvm::objcarc::AutoreleasepoolPush, B, llvm::SmallVectorTemplateCommon< T >::back(), llvm::BlotMapVector< KeyT, ValueT >::begin(), llvm::BasicBlock::begin(), llvm::BlotMapVector< KeyT, ValueT >::blot(), llvm::objcarc::Call, llvm::objcarc::RRInfo::Calls, llvm::SmallPtrSetImplBase::clear(), llvm::objcarc::CopyWeak, llvm::SmallPtrSetImpl< PtrType >::count(), llvm::CallInst::Create(), llvm::dbgs(), llvm::objcarc::DestroyWeak, E, llvm::SmallVectorBase::empty(), llvm::BlotMapVector< KeyT, ValueT >::end(), llvm::DenseMapBase< DenseMap< KeyT, ValueT, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::DenseMapBase< DenseMap< KeyT, ValueT, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::erase(), llvm::SmallPtrSetImpl< PtrType >::erase(), llvm::Instruction::eraseFromParent(), llvm::objcarc::EraseInstruction(), llvm::BlotMapVector< KeyT, ValueT >::find(), llvm::DenseMapBase< DenseMap< KeyT, ValueT, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::find(), llvm::objcarc::GetARCInstKind(), llvm::CallBase::getArgOperand(), llvm::objcarc::GetArgRCIdentityRoot(), llvm::objcarc::GetBasicARCInstKind(), llvm::InstIterator< BB_t, BB_i_t, BI_t, II_t >::getBasicBlockIterator(), llvm::Type::getContext(), llvm::Function::getEntryBlock(), llvm::InstIterator< BB_t, BB_i_t, BI_t, II_t >::getInstructionIterator(), llvm::Type::getInt8Ty(), llvm::Instruction::getParent(), llvm::GlobalValue::getParent(), llvm::objcarc::GetRCIdentityRoot(), llvm::BasicBlock::getTerminator(), llvm::Value::getType(), llvm::PointerType::getUnqual(), I, llvm::objcarc::ImpreciseRelease, llvm::objcarc::InitWeak, llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::inst_begin(), llvm::inst_end(), llvm::objcarc::IntrinsicUser, llvm::objcarc::RRInfo::IsTailCallRelease, llvm::objcarc::RRInfo::KnownSafe, LLVM_DEBUG, llvm_unreachable, llvm::objcarc::LoadWeak, llvm::objcarc::LoadWeakRetained, llvm::MayAlias, llvm::objcarc::MoveWeak, llvm::MustAlias, llvm::NoAlias, llvm::objcarc::None, llvm::objcarc::NoObjCARCExceptions, llvm::PartialAlias, llvm::SmallVectorTemplateBase< T >::pop_back(), llvm::SmallVectorImpl< T >::pop_back_val(), llvm::pred_begin(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::SmallVectorTemplateBase< T >::push_back(), llvm::objcarc::Release, llvm::objcarc::RRInfo::ReleaseMetadata, llvm::Value::replaceAllUsesWith(), llvm::objcarc::Retain, llvm::reverse(), llvm::objcarc::RRInfo::ReverseInsertPts, llvm::CallBase::setDoesNotThrow(), llvm::Instruction::setMetadata(), llvm::CallInst::setTailCall(), llvm::objcarc::StoreWeak, llvm::Value::use_empty(), llvm::objcarc::User, and llvm::Value::users().

◆ createObjCARCOptPass()

objc ObjC ARC false Pass * llvm::createObjCARCOptPass ( )

Definition at line 564 of file ObjCARCOpts.cpp.

References llvm::AnalysisUsage::addRequired(), Arg, assert(), llvm::objcarc::Autorelease, llvm::objcarc::AutoreleasePoolBoundary, llvm::objcarc::AutoreleaseRV, llvm::BasicBlock::back(), llvm::SmallVectorTemplateCommon< T >::begin(), llvm::BasicBlock::begin(), llvm::SmallPtrSetImpl< PtrType >::begin(), C, llvm::objcarc::Call, llvm::objcarc::ClaimRV, llvm::classifyEHPersonality(), llvm::colorEHFunclets(), llvm::objcarc::CopyWeak, llvm::detail::DenseSetImpl< ValueT, SmallDenseMap< ValueT, detail::DenseSetEmpty, InlineBuckets, ValueInfoT, detail::DenseSetPair< ValueT > >, ValueInfoT >::count(), llvm::CallInst::Create(), llvm::dbgs(), llvm::objcarc::DestroyWeak, llvm::dyn_cast(), E, llvm::SmallVectorImpl< T >::emplace_back(), llvm::SmallVectorBase::empty(), llvm::DenseMapBase< DenseMap< KeyT, ValueT, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::empty(), llvm::SmallVectorTemplateCommon< T >::end(), llvm::Instruction::eraseFromParent(), llvm::objcarc::EraseInstruction(), F(), llvm::DenseMapBase< DenseMap< KeyT, ValueT, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::find(), llvm::objcarc::FindDependencies(), FindSingleUseIdentifiedObject(), llvm::TinyPtrVector< EltTy >::front(), llvm::MDNode::get(), llvm::UndefValue::get(), llvm::CallBase::getArgOperand(), llvm::objcarc::GetArgRCIdentityRoot(), llvm::objcarc::GetBasicARCInstKind(), llvm::Value::getContext(), llvm::objcarc::getEquivalentPHIs(), llvm::PHINode::getIncomingBlock(), llvm::PHINode::getIncomingValue(), llvm::CallSiteBase< FunTy, BBTy, ValTy, UserTy, UseTy, InstrTy, CallTy, InvokeTy, IterTy >::getInstruction(), llvm::ilist_node_impl< OptionsT >::getIterator(), llvm::Instruction::getMetadata(), llvm::Constant::getNullValue(), llvm::PHINode::getNumIncomingValues(), llvm::CallBase::getNumOperandBundles(), llvm::Instruction::getNumSuccessors(), llvm::CallBase::getOperandBundleAt(), llvm::Instruction::getParent(), llvm::Function::getPersonalityFn(), llvm::objcarc::GetRCIdentityRoot(), llvm::BasicBlock::getTerminator(), llvm::Value::getType(), llvm::Function::hasPersonalityFn(), I, llvm::objcarc::ImpreciseRelease, llvm::objcarc::InitWeak, llvm::detail::DenseSetImpl< ValueT, SmallDenseMap< ValueT, detail::DenseSetEmpty, InlineBuckets, ValueInfoT, detail::DenseSetPair< ValueT > >, ValueInfoT >::insert(), llvm::Instruction::insertBefore(), llvm::inst_begin(), llvm::inst_end(), llvm::objcarc::IsAlwaysTail(), llvm::objcarc::IsAutorelease(), llvm::objcarc::IsNeverTail(), llvm::objcarc::IsNoopInstruction(), llvm::objcarc::IsNoopOnNull(), llvm::objcarc::IsNoThrow(), llvm::objcarc::IsNullOrUndef(), llvm::isScopedEHPersonality(), LLVM_DEBUG, llvm_unreachable, llvm::objcarc::LoadWeak, llvm::objcarc::LoadWeakRetained, llvm::objcarc::MoveWeak, llvm::objcarc::NeedsPositiveRetainCount, llvm::objcarc::None, llvm::objcarc::NoopCast, llvm::LLVMContext::OB_funclet, llvm::SmallVectorImpl< T >::pop_back_val(), llvm::SmallVectorTemplateBase< T >::push_back(), llvm::objcarc::Release, llvm::Value::replaceAllUsesWith(), llvm::objcarc::Retain, llvm::objcarc::RetainBlock, llvm::objcarc::RetainRV, llvm::CallBase::setArgOperand(), llvm::CallBase::setCalledFunction(), setDoesNotThrow(), llvm::Instruction::setMetadata(), llvm::AnalysisUsage::setPreservesCFG(), llvm::CallInst::setTailCall(), llvm::SmallPtrSetImplBase::size(), llvm::TinyPtrVector< EltTy >::size(), llvm::objcarc::StoreWeak, llvm::Value::use_empty(), Users, and llvm::Value::users().

◆ FindPredecessorAutoreleaseWithSafePath()

static CallInst* FindPredecessorAutoreleaseWithSafePath	(	const Value *	Arg,
		BasicBlock *	BB,
		ReturnInst *	Ret,
		SmallPtrSetImpl< Instruction *> &	DepInsts,
		SmallPtrSetImpl< const BasicBlock *> &	V,
		ProvenanceAnalysis &	PA
	)

static

Look for an ``autorelease'' instruction dependent on Arg such that there are no instructions dependent on Arg that need a positive ref count in between the autorelease and the ret.

Definition at line 2067 of file ObjCARCOpts.cpp.

References llvm::AreStatisticsEnabled(), llvm::objcarc::Autorelease, llvm::objcarc::AutoreleaseRV, llvm::BasicBlock::back(), llvm::SmallPtrSetImpl< PtrType >::begin(), llvm::SmallPtrSetImplBase::clear(), llvm::objcarc::CopyWeak, llvm::dbgs(), llvm::objcarc::DestroyWeak, llvm::dyn_cast(), E, llvm::objcarc::EnableARCOpts, llvm::objcarc::EraseInstruction(), llvm::objcarc::FindDependencies(), FindPredecessorRetainWithSafePath(), llvm::objcarc::GetArgRCIdentityRoot(), llvm::objcarc::GetBasicARCInstKind(), llvm::Value::getName(), llvm::User::getOperand(), llvm::objcarc::GetRCIdentityRoot(), llvm::Function::getReturnType(), HasSafePathToPredecessorCall(), I, llvm::objcarc::InitWeak, llvm::inst_begin(), llvm::inst_end(), llvm::objcarc::IsAutorelease(), llvm::Type::isPointerTy(), LLVM_DEBUG, llvm::objcarc::LoadWeak, llvm::objcarc::LoadWeakRetained, llvm::objcarc::ModuleHasARC(), llvm::objcarc::MoveWeak, llvm::objcarc::NeedsPositiveRetainCount, llvm::objcarc::Release, llvm::MipsISD::Ret, llvm::objcarc::Retain, llvm::objcarc::RetainBlock, llvm::objcarc::RetainRV, runOnFunction(), llvm::SmallPtrSetImplBase::size(), and llvm::objcarc::StoreWeak.

◆ FindPredecessorRetainWithSafePath()

static CallInst* FindPredecessorRetainWithSafePath	(	const Value *	Arg,
		BasicBlock *	BB,
		Instruction *	Autorelease,
		SmallPtrSetImpl< Instruction *> &	DepInsts,
		SmallPtrSetImpl< const BasicBlock *> &	Visited,
		ProvenanceAnalysis &	PA
	)

static

Find a dependent retain that precedes the given autorelease for which there is nothing in between the two instructions that can affect the ref count of Arg.

Definition at line 2042 of file ObjCARCOpts.cpp.

References Arg, llvm::SmallPtrSetImpl< PtrType >::begin(), llvm::objcarc::CanChangeRetainCount, llvm::objcarc::FindDependencies(), llvm::objcarc::GetArgRCIdentityRoot(), llvm::objcarc::GetBasicARCInstKind(), llvm::objcarc::IsRetain(), llvm::objcarc::Retain, and llvm::SmallPtrSetImplBase::size().

Referenced by FindPredecessorAutoreleaseWithSafePath().

◆ HasSafePathToPredecessorCall()

static bool HasSafePathToPredecessorCall	(	const Value *	Arg,
		Instruction *	Retain,
		SmallPtrSetImpl< Instruction *> &	DepInsts,
		SmallPtrSetImpl< const BasicBlock *> &	Visited,
		ProvenanceAnalysis &	PA
	)

static

Check if there is a dependent call earlier that does not have anything in between the Retain and the call that can affect the reference count of their shared pointer argument.

Note that Retain need not be in BB.

Definition at line 2018 of file ObjCARCOpts.cpp.

References llvm::objcarc::Call, llvm::objcarc::CallOrUser, llvm::objcarc::CanChangeRetainCount, llvm::objcarc::FindDependencies(), llvm::objcarc::GetBasicARCInstKind(), llvm::Instruction::getParent(), and llvm::objcarc::Retain.

Referenced by FindPredecessorAutoreleaseWithSafePath().

◆ INITIALIZE_PASS_BEGIN()

INITIALIZE_PASS_BEGIN	(	ObjCARCOpt	,
		"objc-arc"	,
		"ObjC ARC optimization"	,
		false	,
		false
	)

◆ operator<<()

raw_ostream & llvm::operator<<	(	raw_ostream &	OS,
		BBState &	BBState
	)

Definition at line 422 of file ObjCARCOpts.cpp.

References Arg, llvm::objcarc::AutoreleaseRV, llvm::dbgs(), E, F(), llvm::objcarc::PtrState::GetSeq(), llvm::objcarc::PtrState::HasKnownPositiveRefCount(), I, llvm::objcarc::PtrState::IsCFGHazardAfflicted(), llvm::objcarc::PtrState::IsKnownSafe(), llvm::objcarc::PtrState::IsTrackingImpreciseReleases(), LLVM_DEBUG, P, llvm::objcarc::Retain, llvm::objcarc::RetainRV, and runOnFunction().

◆ STATISTIC() [1/10]

STATISTIC	(	NumNoops	,
		"Number of no-op objc calls eliminated"
	)

◆ STATISTIC() [2/10]

STATISTIC	(	NumPartialNoops	,
		"Number of partially no-op objc calls eliminated"
	)

◆ STATISTIC() [3/10]

STATISTIC	(	NumAutoreleases	,
		"Number of autoreleases converted to releases"
	)

◆ STATISTIC() [4/10]

STATISTIC	(	NumRets	,
		"Number of return value forwarding " "retain+autoreleases eliminated"
	)

◆ STATISTIC() [5/10]

STATISTIC	(	NumRRs	,
		"Number of retain+release paths eliminated"
	)

◆ STATISTIC() [6/10]

STATISTIC	(	NumPeeps	,
		"Number of calls peephole-optimized"
	)

◆ STATISTIC() [7/10]

STATISTIC	(	NumRetainsBeforeOpt	,
		"Number of retains before optimization"
	)

◆ STATISTIC() [8/10]

STATISTIC	(	NumReleasesBeforeOpt	,
		"Number of releases before optimization"
	)

◆ STATISTIC() [9/10]

STATISTIC	(	NumRetainsAfterOpt	,
		"Number of retains after optimization"
	)

◆ STATISTIC() [10/10]

STATISTIC	(	NumReleasesAfterOpt	,
		"Number of releases after optimization"
	)

Variable Documentation

◆ arc

objc arc

Definition at line 562 of file ObjCARCOpts.cpp.

◆ false

objc ObjC ARC false

Definition at line 562 of file ObjCARCOpts.cpp.

◆ ID

char ObjCARCOpt::ID = 0

static

Definition at line 547 of file ObjCARCOpts.cpp.

◆ optimization

objc ObjC ARC optimization

Definition at line 562 of file ObjCARCOpts.cpp.

◆ OverflowOccurredValue

const unsigned BBState::OverflowOccurredValue = 0xffffffff

static

Definition at line 204 of file ObjCARCOpts.cpp.

Namespaces

Functions

Variables

Detailed Description

Function Documentation

◆ CheckForCanReleaseCFGHazard()

◆ CheckForUseCFGHazard()

◆ ComputePostOrders()

◆ createObjCARCOptPass()

◆ FindPredecessorAutoreleaseWithSafePath()

◆ FindPredecessorRetainWithSafePath()

◆ HasSafePathToPredecessorCall()

◆ INITIALIZE_PASS_BEGIN()

◆ operator<<()

◆ STATISTIC() [1/10]

◆ STATISTIC() [2/10]

◆ STATISTIC() [3/10]

◆ STATISTIC() [4/10]

◆ STATISTIC() [5/10]

◆ STATISTIC() [6/10]

◆ STATISTIC() [7/10]

◆ STATISTIC() [8/10]

◆ STATISTIC() [9/10]

◆ STATISTIC() [10/10]

Variable Documentation

◆ arc

◆ false

◆ ID

◆ optimization

◆ OverflowOccurredValue