Compute live ranges of allocas. More...

#include "llvm/Analysis/StackLifetime.h"

Classes
class	LifetimeAnnotationWriter

class	LiveRange
	This class represents a set of interesting instructions where an alloca is live. More...

Public Types
enum class	LivenessType { May , Must }

Public Member Functions
	StackLifetime (const Function &F, ArrayRef< const AllocaInst * > Allocas, LivenessType Type)

void	run ()

iterator_range< filter_iterator< ArrayRef< const IntrinsicInst * >::const_iterator, std::function< bool(const IntrinsicInst *)> > >	getMarkers () const

const LiveRange &	getLiveRange (const AllocaInst *AI) const
	Returns a set of "interesting" instructions where the given alloca is live.

bool	isReachable (const Instruction *I) const
	Returns true if instruction is reachable from entry.

bool	isAliveAfter (const AllocaInst AI, const Instruction I) const
	Returns true if the alloca is alive after the instruction.

LiveRange	getFullLiveRange () const
	Returns a live range that represents an alloca that is live throughout the entire function.

void	print (raw_ostream &O)

Detailed Description

Compute live ranges of allocas.

Live ranges are represented as sets of "interesting" instructions, which are defined as instructions that may start or end an alloca's lifetime. These are:

lifetime.start and lifetime.end intrinsics
first instruction of any basic block Interesting instructions are numbered in the depth-first walk of the CFG, and in the program order inside each basic block.

Definition at line 37 of file StackLifetime.h.

Member Enumeration Documentation

◆ LivenessType

enum class llvm::StackLifetime::LivenessType

strong

Enumerator
May
Must

Definition at line 83 of file StackLifetime.h.

Constructor & Destructor Documentation

◆ StackLifetime()

StackLifetime::StackLifetime	(	const Function &	F,
		ArrayRef< const AllocaInst * >	Allocas,
		LivenessType	Type
	)

Definition at line 318 of file StackLifetime.cpp.

References I, LLVM_DEBUG, and llvm::size().

Member Function Documentation

◆ getFullLiveRange()

LiveRange llvm::StackLifetime::getFullLiveRange ( ) const

inline

Returns a live range that represents an alloca that is live throughout the entire function.

Definition at line 162 of file StackLifetime.h.

Referenced by run().

◆ getLiveRange()

const StackLifetime::LiveRange & StackLifetime::getLiveRange ( const AllocaInst * AI ) const

Returns a set of "interesting" instructions where the given alloca is live.

Not all instructions in a function are interesting: we pick a set that is large enough for LiveRange::Overlaps to be correct.

Definition at line 35 of file StackLifetime.cpp.

References assert(), and IT.

Referenced by isAliveAfter().

◆ getMarkers()

iterator_range< filter_iterator< ArrayRef< const IntrinsicInst * >::const_iterator, std::function< bool(const IntrinsicInst *)> > > llvm::StackLifetime::getMarkers ( ) const

inline

Definition at line 143 of file StackLifetime.h.

References I, and llvm::make_filter_range().

◆ isAliveAfter()

bool StackLifetime::isAliveAfter	(	const AllocaInst *	AI,
		const Instruction *	I
	)		const

Returns true if the alloca is alive after the instruction.

Definition at line 45 of file StackLifetime.cpp.

References assert(), getLiveRange(), I, and llvm::StackLifetime::LiveRange::test().

◆ isReachable()

bool StackLifetime::isReachable ( const Instruction * I ) const

Returns true if instruction is reachable from entry.

Definition at line 41 of file StackLifetime.cpp.

References I.

◆ print()

void StackLifetime::print ( raw_ostream & O )

Definition at line 396 of file StackLifetime.cpp.

References OS, and llvm::Function::print().

Referenced by llvm::StackLifetimePrinterPass::run().

◆ run()

void StackLifetime::run ( )

Definition at line 330 of file StackLifetime.cpp.

References getFullLiveRange(), I, LLVM_DEBUG, May, Must, and llvm::BitVector::test().