gem5::prefetch::PIF::CompactorEntry Struct Reference

The compactor tracks retired instructions addresses, leveraging the spatial and temporal locality among instructions for compaction. More...

Public Member Functions
	CompactorEntry ()
	CompactorEntry (Addr, unsigned int, unsigned int)
bool	inSameSpatialRegion (Addr addr, unsigned int log_blk_size, bool update)
	Checks if a given address is in the same defined spatial region as the compactor entry.
bool	hasAddress (Addr target, unsigned int log_blk_size) const
	Checks if the provided address is contained in this spatial region and if its corresponding bit vector entry is set.
void	getPredictedAddresses (unsigned int log_blk_size, std::vector< AddrPriority > &addresses) const
	Fills the provided vector with the predicted addresses using the recorded bit vectors of the entry.

Public Attributes
Addr	trigger
std::vector< bool >	prec
std::vector< bool >	succ

Private Member Functions
Addr	distanceFromTrigger (Addr addr, unsigned int log_blk_size) const
	Computes the distance, in cache blocks, from an address to the trigger of the entry.

Detailed Description

The compactor tracks retired instructions addresses, leveraging the spatial and temporal locality among instructions for compaction.

It comprises the spatial and temporal compaction mechanisms.

Taking advantage of the spatial locality across instruction blocks, the spatial compactor combines instruction-block addresses that fall within a 'spatial region', a group of adjacent instruction blocks. When an instruction outside the current spatial region retires, the existing spatial region is sent to the temporal compactor.

The temporal compactor tracks a small number of the most-recently-observed spatial region records.

Definition at line 78 of file pif.hh.

Constructor & Destructor Documentation

CompactorEntry() [1/2]

gem5::prefetch::PIF::CompactorEntry::CompactorEntry ( )

inline

Definition at line 83 of file pif.hh.

CompactorEntry() [2/2]

gem5::prefetch::PIF::CompactorEntry::CompactorEntry	(	Addr	addr,
		unsigned int	prec_size,
		unsigned int	succ_size )

Definition at line 57 of file pif.cc.

References gem5::X86ISA::addr, prec, succ, and trigger.

Member Function Documentation

distanceFromTrigger()

Addr gem5::prefetch::PIF::CompactorEntry::distanceFromTrigger ( Addr addr, unsigned int log_blk_size ) const

private

Computes the distance, in cache blocks, from an address to the trigger of the entry.

Parameters

addr	address to compute the distance from the trigger
log_blk_distance	log_2(block size of the cache)

Returns

distance in cache blocks from the address to the trigger

Definition at line 66 of file pif.cc.

References gem5::X86ISA::trigger.

getPredictedAddresses()

void gem5::prefetch::PIF::CompactorEntry::getPredictedAddresses	(	unsigned int	log_blk_size,
		std::vector< AddrPriority > &	addresses ) const

Fills the provided vector with the predicted addresses using the recorded bit vectors of the entry.

Parameters

log_blk_distance	log_2(block size of the cache)
addresses	reference to a vector to add the generated addresses

Definition at line 111 of file pif.cc.

References gem5::ArmISA::i, gem5::RiscvISA::succ, and gem5::X86ISA::trigger.

hasAddress()

bool gem5::prefetch::PIF::CompactorEntry::hasAddress	(	Addr	target,
		unsigned int	log_blk_size ) const

Checks if the provided address is contained in this spatial region and if its corresponding bit vector entry is set.

Parameters

target	address to check
log_blk_distance	log_2(block size of the cache)

Returns

TRUE if target has its bit set

Definition at line 95 of file pif.cc.

References gem5::RiscvISA::succ, and gem5::X86ISA::trigger.

inSameSpatialRegion()

bool gem5::prefetch::PIF::CompactorEntry::inSameSpatialRegion	(	Addr	addr,
		unsigned int	log_blk_size,
		bool	update )

Checks if a given address is in the same defined spatial region as the compactor entry.

Parameters

addr	Address to check if it's inside the spatial region
log_blk_distance	log_2(block size of the cache)
update	if true, set the corresponding succ/prec entry

Returns

TRUE if they are in the same spatial region, FALSE otherwise

Definition at line 77 of file pif.cc.

References gem5::MipsISA::pc, gem5::RiscvISA::succ, gem5::X86ISA::trigger, and gem5::Clocked::update().

Referenced by gem5::prefetch::PIF::notifyRetiredInst().

Member Data Documentation

prec

std::vector<bool> gem5::prefetch::PIF::CompactorEntry::prec

Definition at line 81 of file pif.hh.

Referenced by CompactorEntry().

succ

std::vector<bool> gem5::prefetch::PIF::CompactorEntry::succ

Definition at line 82 of file pif.hh.

Referenced by CompactorEntry().

trigger

Addr gem5::prefetch::PIF::CompactorEntry::trigger

Definition at line 80 of file pif.hh.

Referenced by CompactorEntry(), and gem5::prefetch::PIF::notifyRetiredInst().

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The documentation for this struct was generated from the following files:

• mem/cache/prefetch/pif.hh
• mem/cache/prefetch/pif.cc