This is an alternative analysis pass to BranchProbabilityInfoWrapperPass. More...

#include "llvm/Analysis/LazyBranchProbabilityInfo.h"

Inheritance diagram for llvm::LazyBranchProbabilityInfoPass:

Public Member Functions
	LazyBranchProbabilityInfoPass ()

BranchProbabilityInfo &	getBPI ()
	Compute and return the branch probabilities.

const BranchProbabilityInfo &	getBPI () const
	Compute and return the branch probabilities.

void	getAnalysisUsage (AnalysisUsage &AU) const override
	getAnalysisUsage - This function should be overriden by passes that need analysis information to do their job.

bool	runOnFunction (Function &F) override
	runOnFunction - Virtual method overriden by subclasses to do the per-function processing of the pass.

void	releaseMemory () override
	releaseMemory() - This member can be implemented by a pass if it wants to be able to release its memory when it is no longer needed.

void	print (raw_ostream &OS, const Module *M) const override
	print - Print out the internal state of the pass.

Public Member Functions inherited from llvm::FunctionPass
	FunctionPass (char &pid)

Pass *	createPrinterPass (raw_ostream &OS, const std::string &Banner) const override
	createPrinterPass - Get a function printer pass.

virtual bool	runOnFunction (Function &F)=0
	runOnFunction - Virtual method overriden by subclasses to do the per-function processing of the pass.

void	assignPassManager (PMStack &PMS, PassManagerType T) override
	Find appropriate Function Pass Manager or Call Graph Pass Manager in the PM Stack and add self into that manager.

PassManagerType	getPotentialPassManagerType () const override
	Return what kind of Pass Manager can manage this pass.

Public Member Functions inherited from llvm::Pass
	Pass (PassKind K, char &pid)

	Pass (const Pass &)=delete

Pass &	operator= (const Pass &)=delete

virtual	~Pass ()

PassKind	getPassKind () const

virtual StringRef	getPassName () const
	getPassName - Return a nice clean name for a pass.

AnalysisID	getPassID () const
	getPassID - Return the PassID number that corresponds to this pass.

virtual bool	doInitialization (Module &)
	doInitialization - Virtual method overridden by subclasses to do any necessary initialization before any pass is run.

virtual bool	doFinalization (Module &)
	doFinalization - Virtual method overriden by subclasses to do any necessary clean up after all passes have run.

virtual void	print (raw_ostream &OS, const Module *M) const
	print - Print out the internal state of the pass.

void	dump () const

virtual Pass *	createPrinterPass (raw_ostream &OS, const std::string &Banner) const =0
	createPrinterPass - Get a Pass appropriate to print the IR this pass operates on (Module, Function or MachineFunction).

virtual void	assignPassManager (PMStack &, PassManagerType)
	Each pass is responsible for assigning a pass manager to itself.

virtual void	preparePassManager (PMStack &)
	Check if available pass managers are suitable for this pass or not.

virtual PassManagerType	getPotentialPassManagerType () const
	Return what kind of Pass Manager can manage this pass.

void	setResolver (AnalysisResolver *AR)

AnalysisResolver *	getResolver () const

virtual void	getAnalysisUsage (AnalysisUsage &) const
	getAnalysisUsage - This function should be overriden by passes that need analysis information to do their job.

virtual void	releaseMemory ()
	releaseMemory() - This member can be implemented by a pass if it wants to be able to release its memory when it is no longer needed.

virtual void *	getAdjustedAnalysisPointer (AnalysisID ID)
	getAdjustedAnalysisPointer - This method is used when a pass implements an analysis interface through multiple inheritance.

virtual ImmutablePass *	getAsImmutablePass ()

virtual PMDataManager *	getAsPMDataManager ()

virtual void	verifyAnalysis () const
	verifyAnalysis() - This member can be implemented by a analysis pass to check state of analysis information.

virtual void	dumpPassStructure (unsigned Offset=0)

template<typename AnalysisType >
AnalysisType *	getAnalysisIfAvailable () const
	getAnalysisIfAvailable<AnalysisType>() - Subclasses use this function to get analysis information that might be around, for example to update it.

bool	mustPreserveAnalysisID (char &AID) const
	mustPreserveAnalysisID - This method serves the same function as getAnalysisIfAvailable, but works if you just have an AnalysisID.

template<typename AnalysisType >
AnalysisType &	getAnalysis () const
	getAnalysis<AnalysisType>() - This function is used by subclasses to get to the analysis information that they claim to use by overriding the getAnalysisUsage function.

template<typename AnalysisType >
AnalysisType &	getAnalysis (Function &F, bool *Changed=nullptr)
	getAnalysis<AnalysisType>() - This function is used by subclasses to get to the analysis information that they claim to use by overriding the getAnalysisUsage function.

template<typename AnalysisType >
AnalysisType &	getAnalysisID (AnalysisID PI) const

template<typename AnalysisType >
AnalysisType &	getAnalysisID (AnalysisID PI, Function &F, bool *Changed=nullptr)

Static Public Member Functions
static void	getLazyBPIAnalysisUsage (AnalysisUsage &AU)
	Helper for client passes to set up the analysis usage on behalf of this pass.

Static Public Member Functions inherited from llvm::Pass
static const PassInfo *	lookupPassInfo (const void *TI)

static const PassInfo *	lookupPassInfo (StringRef Arg)

static Pass *	createPass (AnalysisID ID)

Static Public Attributes
static char	ID = 0

Additional Inherited Members
Protected Member Functions inherited from llvm::FunctionPass
bool	skipFunction (const Function &F) const
	Optional passes call this function to check whether the pass should be skipped.

Detailed Description

This is an alternative analysis pass to BranchProbabilityInfoWrapperPass.

The difference is that with this pass the branch probabilities are not computed when the analysis pass is executed but rather when the BPI results is explicitly requested by the analysis client.

There are some additional requirements for any client pass that wants to use the analysis:

The pass needs to initialize dependent passes with:

INITIALIZE_PASS_DEPENDENCY(LazyBPIPass)
Similarly, getAnalysisUsage should call:

LazyBranchProbabilityInfoPass::getLazyBPIAnalysisUsage(AU)
The computed BPI should be requested with getAnalysis<LazyBranchProbabilityInfoPass>().getBPI() before LoopInfo could be invalidated for example by changing the CFG.

Note that it is expected that we wouldn't need this functionality for the new PM since with the new PM, analyses are executed on demand.

Definition at line 49 of file LazyBranchProbabilityInfo.h.

Constructor & Destructor Documentation

◆ LazyBranchProbabilityInfoPass()

LazyBranchProbabilityInfoPass::LazyBranchProbabilityInfoPass ( )

Definition at line 35 of file LazyBranchProbabilityInfo.cpp.

References llvm::PassRegistry::getPassRegistry(), and llvm::initializeLazyBranchProbabilityInfoPassPass().

Member Function Documentation

◆ getAnalysisUsage()

void LazyBranchProbabilityInfoPass::getAnalysisUsage ( AnalysisUsage & ) const

overridevirtual

getAnalysisUsage - This function should be overriden by passes that need analysis information to do their job.

If a pass specifies that it uses a particular analysis result to this function, it can then use the getAnalysis<AnalysisType>() function, below.

Reimplemented from llvm::Pass.

Definition at line 45 of file LazyBranchProbabilityInfo.cpp.

References llvm::AnalysisUsage::addRequiredTransitive(), and llvm::AnalysisUsage::setPreservesAll().

◆ getBPI() [1/2]

BranchProbabilityInfo & llvm::LazyBranchProbabilityInfoPass::getBPI ( )

inline

Compute and return the branch probabilities.

Definition at line 91 of file LazyBranchProbabilityInfo.h.

◆ getBPI() [2/2]

const BranchProbabilityInfo & llvm::LazyBranchProbabilityInfoPass::getBPI ( ) const

inline

Compute and return the branch probabilities.

Definition at line 94 of file LazyBranchProbabilityInfo.h.

◆ getLazyBPIAnalysisUsage()

void LazyBranchProbabilityInfoPass::getLazyBPIAnalysisUsage ( AnalysisUsage & AU )

static

Helper for client passes to set up the analysis usage on behalf of this pass.

Definition at line 65 of file LazyBranchProbabilityInfo.cpp.

References llvm::AnalysisUsage::addRequiredTransitive().

Referenced by llvm::LazyBlockFrequencyInfoPass::getAnalysisUsage(), and llvm::LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage().

◆ print()

void LazyBranchProbabilityInfoPass::print	(	raw_ostream &	OS,
		const Module *	M
	)		const

overridevirtual

print - Print out the internal state of the pass.

This is called by Analyze to print out the contents of an analysis. Otherwise it is not necessary to implement this method. Beware that the module pointer MAY be null. This automatically forwards to a virtual function that does not provide the Module* in case the analysis doesn't need it it can just be ignored.

Reimplemented from llvm::Pass.

Definition at line 40 of file LazyBranchProbabilityInfo.cpp.

References OS.

◆ releaseMemory()

void LazyBranchProbabilityInfoPass::releaseMemory ( )

overridevirtual

releaseMemory() - This member can be implemented by a pass if it wants to be able to release its memory when it is no longer needed.

The default behavior of passes is to hold onto memory for the entire duration of their lifetime (which is the entire compile time). For pipelined passes, this is not a big deal because that memory gets recycled every time the pass is invoked on another program unit. For IP passes, it is more important to free memory when it is unused.

Optionally implement this function to release pass memory when it is no longer used.

Reimplemented from llvm::Pass.

Definition at line 55 of file LazyBranchProbabilityInfo.cpp.