#include <lsq.hh>

Inheritance diagram for gem5::minor::LSQ::StoreBuffer:

Public Member Functions
	StoreBuffer (std::string name_, LSQ &lsq_, unsigned int store_buffer_size, unsigned int store_limit_per_cycle)

bool	canInsert () const
	Can a new request be inserted into the queue?

void	deleteRequest (LSQRequestPtr request)
	Delete the given request and free the slot it occupied.

void	insert (LSQRequestPtr request)
	Insert a request at the back of the queue.

AddrRangeCoverage	canForwardDataToLoad (LSQRequestPtr request, unsigned int &found_slot)
	Look for a store which satisfies the given load.

void	forwardStoreData (LSQRequestPtr load, unsigned int slot_number)
	Fill the given packet with appropriate date from slot slot_number.

unsigned int	numUnissuedStores ()
	Number of stores in the store buffer which have not been completely issued to the memory system.

void	countIssuedStore (LSQRequestPtr request)
	Count a store being issued to memory by decrementing numUnissuedAccesses.

bool	isDrained () const
	Drained if there is absolutely nothing left in the buffer.

void	step ()
	Try to issue more stores to memory.

void	minorTrace () const
	Report queue contents for MinorTrace.

Public Member Functions inherited from gem5::Named
	Named (std::string_view name_)

virtual	~Named ()=default

virtual std::string	name () const

Public Attributes
LSQ &	lsq
	My owner.

const unsigned int	numSlots
	Number of slots, this is a bound on the size of slots.

const unsigned int	storeLimitPerCycle
	Maximum number of stores that can be issued per cycle.

std::deque< LSQRequestPtr >	slots
	Queue of store requests on their way to memory.

unsigned int	numUnissuedAccesses
	Number of occupied slots which have not yet issued a memory access.

Detailed Description

Store buffer.

This contains stores which have been committed but whose memory transfers have not yet been issued. Load data can be forwarded out of the store buffer

Definition at line 471 of file lsq.hh.

Constructor & Destructor Documentation

◆ StoreBuffer()

gem5::minor::LSQ::StoreBuffer::StoreBuffer	(	std::string	name_,
		LSQ &	lsq_,
		unsigned int	store_buffer_size,
		unsigned int	store_limit_per_cycle )

Definition at line 1684 of file lsq.cc.

References gem5::minor::LSQ::LSQ(), lsq, gem5::Named::Named(), numSlots, numUnissuedAccesses, slots, and storeLimitPerCycle.

Member Function Documentation

◆ canForwardDataToLoad()

LSQ::AddrRangeCoverage gem5::minor::LSQ::StoreBuffer::canForwardDataToLoad	(	LSQRequestPtr	request,
		unsigned int &	found_slot )

Look for a store which satisfies the given load.

Returns an indication whether the forwarding request can be wholly, partly or not all all satisfied. If the request can be wholly satisfied, the store buffer slot number which can be used is returned in found_slot

Definition at line 763 of file lsq.cc.

References gem5::minor::LSQ::LSQRequest::containsAddrRangeOf(), DPRINTF, gem5::ArmISA::i, gem5::minor::LSQ::LSQRequest::inst, gem5::minor::LSQ::NoAddrRangeCoverage, gem5::minor::LSQ::LSQRequest::packet, gem5::Packet::req, gem5::minor::LSQ::LSQRequest::request, and slots.

◆ canInsert()

bool gem5::minor::LSQ::StoreBuffer::canInsert ( ) const

Can a new request be inserted into the queue?

Definition at line 720 of file lsq.cc.

References numSlots, and slots.

Referenced by insert().

◆ countIssuedStore()

void gem5::minor::LSQ::StoreBuffer::countIssuedStore ( LSQRequestPtr request )

Count a store being issued to memory by decrementing numUnissuedAccesses.

Does not count barrier requests as they will be handles as barriers are cleared from the buffer

Definition at line 834 of file lsq.cc.

References gem5::minor::LSQ::LSQRequest::isBarrier(), and numUnissuedAccesses.

Referenced by step().

◆ deleteRequest()

void gem5::minor::LSQ::StoreBuffer::deleteRequest ( LSQRequestPtr request )

Delete the given request and free the slot it occupied.

Definition at line 727 of file lsq.cc.

References DPRINTF, gem5::minor::LSQ::LSQRequest::inst, and slots.

◆ forwardStoreData()

void gem5::minor::LSQ::StoreBuffer::forwardStoreData	(	LSQRequestPtr	load,
		unsigned int	slot_number )

Fill the given packet with appropriate date from slot slot_number.

Definition at line 804 of file lsq.cc.

References gem5::minor::LSQ::LSQRequest::containsAddrRangeOf(), DPRINTF, gem5::minor::LSQ::FullAddrRangeCoverage, gem5::Packet::getPtr(), gem5::minor::LSQ::LSQRequest::isLoad, gem5::minor::LSQ::LSQRequest::packet, gem5::minor::LSQ::LSQRequest::request, and slots.

◆ insert()

void gem5::minor::LSQ::StoreBuffer::insert ( LSQRequestPtr request )

Insert a request at the back of the queue.

Definition at line 741 of file lsq.cc.

References canInsert(), gem5::minor::LSQ::LSQRequest::Complete, DPRINTF, gem5::minor::Pipeline::ExecuteStageId, gem5::minor::LSQ::LSQRequest::inst, lsq, gem5::Named::name(), numUnissuedAccesses, gem5::minor::LSQ::LSQRequest::setState(), slots, gem5::minor::LSQ::LSQRequest::state, gem5::minor::LSQ::LSQRequest::StoreInStoreBuffer, and warn.

◆ isDrained()

bool gem5::minor::LSQ::StoreBuffer::isDrained ( ) const

inline

Drained if there is absolutely nothing left in the buffer.

Definition at line 528 of file lsq.hh.

References slots.

◆ minorTrace()

void gem5::minor::LSQ::StoreBuffer::minorTrace ( ) const

Report queue contents for MinorTrace.

Definition at line 930 of file lsq.cc.

References gem5::ArmISA::i, gem5::minor::minorTrace(), numSlots, numUnissuedAccesses, gem5::X86ISA::os, gem5::minor::LSQ::LSQRequest::reportData(), and slots.

◆ numUnissuedStores()

unsigned int gem5::minor::LSQ::StoreBuffer::numUnissuedStores ( )

inline

Number of stores in the store buffer which have not been completely issued to the memory system.

Definition at line 520 of file lsq.hh.

References numUnissuedAccesses.

◆ step()

void gem5::minor::LSQ::StoreBuffer::step ( )

Try to issue more stores to memory.

Definition at line 843 of file lsq.cc.

References countIssuedStore(), DPRINTF, gem5::ArmISA::i, gem5::minor::LSQ::LSQRequest::inst, gem5::minor::LSQ::LSQRequest::isBarrier(), gem5::minor::LSQ::LSQRequest::isComplete(), lsq, gem5::minor::LSQ::MemoryNeedsRetry, gem5::minor::LSQ::MemoryRunning, numUnissuedAccesses, gem5::minor::LSQ::LSQRequest::sentAllPackets(), slots, gem5::minor::LSQ::LSQRequest::state, gem5::minor::LSQ::LSQRequest::StoreBufferIssuing, and storeLimitPerCycle.

Member Data Documentation

◆ lsq

LSQ& gem5::minor::LSQ::StoreBuffer::lsq

My owner.

Definition at line 475 of file lsq.hh.

Referenced by insert(), step(), and StoreBuffer().

◆ numSlots

const unsigned int gem5::minor::LSQ::StoreBuffer::numSlots

Number of slots, this is a bound on the size of slots.

Definition at line 478 of file lsq.hh.

Referenced by canInsert(), minorTrace(), and StoreBuffer().

◆ numUnissuedAccesses

unsigned int gem5::minor::LSQ::StoreBuffer::numUnissuedAccesses

Number of occupied slots which have not yet issued a memory access.

Definition at line 489 of file lsq.hh.

Referenced by countIssuedStore(), insert(), minorTrace(), numUnissuedStores(), step(), and StoreBuffer().

◆ slots

std::deque<LSQRequestPtr> gem5::minor::LSQ::StoreBuffer::slots

Queue of store requests on their way to memory.

Definition at line 485 of file lsq.hh.

Referenced by canForwardDataToLoad(), canInsert(), deleteRequest(), forwardStoreData(), insert(), isDrained(), minorTrace(), step(), and StoreBuffer().

◆ storeLimitPerCycle

const unsigned int gem5::minor::LSQ::StoreBuffer::storeLimitPerCycle

Maximum number of stores that can be issued per cycle.

Definition at line 481 of file lsq.hh.

Referenced by step(), and StoreBuffer().

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

cpu/minor/lsq.hh
cpu/minor/lsq.cc

Public Member Functions

Public Attributes