Class that implements the actual LQ and SQ for each specific thread. More...

#include <lsq_unit.hh>

Classes
class	LQSenderState
	Particularisation of the LSQSenderState to the LQ. More...

class	LSQEntry

struct	LSQUnitStats

class	SQEntry

class	SQSenderState
	Particularisation of the LSQSenderState to the SQ. More...

class	WritebackEvent
	Writeback event, specifically for when stores forward data to loads. More...

Public Types
typedef Impl::O3CPU	O3CPU

typedef Impl::DynInstPtr	DynInstPtr

typedef Impl::CPUPol::IEW	IEW

typedef Impl::CPUPol::LSQ	LSQ

typedef Impl::CPUPol::IssueStruct	IssueStruct

using	LSQSenderState = typename LSQ::LSQSenderState

using	LSQRequest = typename Impl::CPUPol::LSQ::LSQRequest

using	LoadQueue = CircularQueue< LQEntry >

using	StoreQueue = CircularQueue< SQEntry >

typedef CircularQueue< LQEntry >::iterator	LQIterator

typedef CircularQueue< SQEntry >::iterator	SQIterator

typedef CircularQueue< LQEntry >	LQueue

typedef CircularQueue< SQEntry >	SQueue

Public Member Functions
	LSQUnit (uint32_t lqEntries, uint32_t sqEntries)
	Constructs an LSQ unit. More...

	LSQUnit (const LSQUnit &l)
	We cannot copy LSQUnit because it has stats for which copy contructor is deleted explicitly. More...

void	init (O3CPU cpu_ptr, IEW iew_ptr, DerivO3CPUParams params, LSQ lsq_ptr, unsigned id)
	Initializes the LSQ unit with the specified number of entries. More...

std::string	name () const
	Returns the name of the LSQ unit. More...

void	setDcachePort (RequestPort *dcache_port)
	Sets the pointer to the dcache port. More...

void	drainSanityCheck () const
	Perform sanity checks after a drain. More...

void	takeOverFrom ()
	Takes over from another CPU's thread. More...

void	insert (const DynInstPtr &inst)
	Inserts an instruction. More...

void	insertLoad (const DynInstPtr &load_inst)
	Inserts a load instruction. More...

void	insertStore (const DynInstPtr &store_inst)
	Inserts a store instruction. More...

Fault	checkViolations (typename LoadQueue::iterator &loadIt, const DynInstPtr &inst)
	Check for ordering violations in the LSQ. More...

void	checkSnoop (PacketPtr pkt)
	Check if an incoming invalidate hits in the lsq on a load that might have issued out of order wrt another load beacuse of the intermediate invalidate. More...

Fault	executeLoad (const DynInstPtr &inst)
	Executes a load instruction. More...

Fault	executeLoad (int lq_idx)

Fault	executeStore (const DynInstPtr &inst)
	Executes a store instruction. More...

void	commitLoad ()
	Commits the head load. More...

void	commitLoads (InstSeqNum &youngest_inst)
	Commits loads older than a specific sequence number. More...

void	commitStores (InstSeqNum &youngest_inst)
	Commits stores older than a specific sequence number. More...

void	writebackStores ()
	Writes back stores. More...

void	completeDataAccess (PacketPtr pkt)
	Completes the data access that has been returned from the memory system. More...

void	squash (const InstSeqNum &squashed_num)
	Squashes all instructions younger than a specific sequence number. More...

bool	violation ()
	Returns if there is a memory ordering violation. More...

DynInstPtr	getMemDepViolator ()
	Returns the memory ordering violator. More...

unsigned	numFreeLoadEntries ()
	Returns the number of free LQ entries. More...

unsigned	numFreeStoreEntries ()
	Returns the number of free SQ entries. More...

int	numLoads ()
	Returns the number of loads in the LQ. More...

int	numStores ()
	Returns the number of stores in the SQ. More...

int	numHtmStarts () const

int	numHtmStops () const

void	resetHtmStartsStops ()

uint64_t	getLatestHtmUid () const

void	setLastRetiredHtmUid (uint64_t htm_uid)

bool	isFull ()
	Returns if either the LQ or SQ is full. More...

bool	isEmpty () const
	Returns if both the LQ and SQ are empty. More...

bool	lqFull ()
	Returns if the LQ is full. More...

bool	sqFull ()
	Returns if the SQ is full. More...

bool	lqEmpty () const
	Returns if the LQ is empty. More...

bool	sqEmpty () const
	Returns if the SQ is empty. More...

unsigned	getCount ()
	Returns the number of instructions in the LSQ. More...

bool	hasStoresToWB ()
	Returns if there are any stores to writeback. More...

int	numStoresToWB ()
	Returns the number of stores to writeback. More...

bool	willWB ()
	Returns if the LSQ unit will writeback on this cycle. More...

void	recvRetry ()
	Handles doing the retry. More...

unsigned int	cacheLineSize ()

bool	trySendPacket (bool isLoad, PacketPtr data_pkt)
	Attempts to send a packet to the cache. More...

void	dumpInsts () const
	Debugging function to dump instructions in the LSQ. More...

void	schedule (Event &ev, Tick when)
	Schedule event for the cpu. More...

BaseTLB *	dTLB ()

bool	recvTimingResp (PacketPtr pkt)
	Handles writing back and completing the load or store that has returned from memory. More...

Fault	read (LSQRequest *req, int load_idx)
	Executes the load at the given index. More...

Fault	write (LSQRequest req, uint8_t data, int store_idx)
	Executes the store at the given index. More...

int	getLoadHead ()
	Returns the index of the head load instruction. More...

InstSeqNum	getLoadHeadSeqNum ()
	Returns the sequence number of the head load instruction. More...

int	getStoreHead ()
	Returns the index of the head store instruction. More...

InstSeqNum	getStoreHeadSeqNum ()
	Returns the sequence number of the head store instruction. More...

bool	isStalled ()
	Returns whether or not the LSQ unit is stalled. More...

Public Attributes
CircularQueue< SQEntry >	storeQueue
	The store queue. More...

LoadQueue	loadQueue
	The load queue. More...

Static Public Attributes
static constexpr auto	MaxDataBytes = MaxVecRegLenInBytes

Protected Attributes
LSQUnit::LSQUnitStats	stats

Private Types
enum	AddrRangeCoverage { AddrRangeCoverage::PartialAddrRangeCoverage, AddrRangeCoverage::FullAddrRangeCoverage, AddrRangeCoverage::NoAddrRangeCoverage }
	Coverage of one address range with another. More...

using	LQEntry = LSQEntry

Private Member Functions
void	resetState ()
	Reset the LSQ state. More...

void	writeback (const DynInstPtr &inst, PacketPtr pkt)
	Writes back the instruction, sending it to IEW. More...

void	writebackBlockedStore ()
	Try to finish a previously blocked write back attempt. More...

void	completeStore (typename StoreQueue::iterator store_idx)
	Completes the store at the specified index. More...

void	storePostSend ()
	Handles completing the send of a store to memory. More...

Private Attributes
O3CPU *	cpu
	Pointer to the CPU. More...

IEW *	iewStage
	Pointer to the IEW stage. More...

LSQ *	lsq
	Pointer to the LSQ. More...

RequestPort *	dcachePort
	Pointer to the dcache port. More...

ThreadID	lsqID
	The LSQUnit thread id. More...

unsigned	depCheckShift
	The number of places to shift addresses in the LSQ before checking for dependency violations. More...

bool	checkLoads
	Should loads be checked for dependency issues. More...

int	loads
	The number of load instructions in the LQ. More...

int	stores
	The number of store instructions in the SQ. More...

int	storesToWB
	The number of store instructions in the SQ waiting to writeback. More...

int	htmStarts

int	htmStops

uint64_t	lastRetiredHtmUid

StoreQueue::iterator	storeWBIt
	The index of the first instruction that may be ready to be written back, and has not yet been written back. More...

Addr	cacheBlockMask
	Address Mask for a cache block (e.g. More...

TimeBuffer< IssueStruct >::wire	fromIssue
	Wire to read information from the issue stage time queue. More...

bool	stalled
	Whether or not the LSQ is stalled. More...

InstSeqNum	stallingStoreIsn
	The store that causes the stall due to partial store to load forwarding. More...

int	stallingLoadIdx
	The index of the above store. More...

PacketPtr	retryPkt
	The packet that needs to be retried. More...

bool	isStoreBlocked
	Whehter or not a store is blocked due to the memory system. More...

bool	storeInFlight
	Whether or not a store is in flight. More...

DynInstPtr	memDepViolator
	The oldest load that caused a memory ordering violation. More...

bool	hasPendingRequest
	Whether or not there is a packet that couldn't be sent because of a lack of cache ports. More...

LSQRequest *	pendingRequest
	The packet that is pending free cache ports. More...

bool	needsTSO
	Flag for memory model. More...

Detailed Description

template<class Impl>
class LSQUnit< Impl >

Class that implements the actual LQ and SQ for each specific thread.

Both are circular queues; load entries are freed upon committing, while store entries are freed once they writeback. The LSQUnit tracks if there are memory ordering violations, and also detects partial load to store forwarding cases (a store only has part of a load's data) that requires the load to wait until the store writes back. In the former case it holds onto the instruction until the dependence unit looks at it, and in the latter it stalls the LSQ until the store writes back. At that point the load is replayed.

Definition at line 78 of file lsq_unit.hh.

Member Typedef Documentation

◆ DynInstPtr

template<class Impl >

typedef Impl::DynInstPtr LSQUnit< Impl >::DynInstPtr

Definition at line 84 of file lsq_unit.hh.

◆ IEW

template<class Impl >

typedef Impl::CPUPol::IEW LSQUnit< Impl >::IEW

Definition at line 85 of file lsq_unit.hh.

◆ IssueStruct

template<class Impl >

typedef Impl::CPUPol::IssueStruct LSQUnit< Impl >::IssueStruct

Definition at line 87 of file lsq_unit.hh.

◆ LoadQueue

template<class Impl >

using LSQUnit< Impl >::LoadQueue = CircularQueue<LQEntry>

Definition at line 218 of file lsq_unit.hh.

◆ LQEntry

template<class Impl >

using LSQUnit< Impl >::LQEntry = LSQEntry

private

Definition at line 207 of file lsq_unit.hh.

◆ LQIterator

template<class Impl >

typedef CircularQueue<LQEntry>::iterator LSQUnit< Impl >::LQIterator

Definition at line 628 of file lsq_unit.hh.

◆ LQueue

template<class Impl >

typedef CircularQueue<LQEntry> LSQUnit< Impl >::LQueue

Definition at line 630 of file lsq_unit.hh.

◆ LSQ

template<class Impl >

typedef Impl::CPUPol::LSQ LSQUnit< Impl >::LSQ

Definition at line 86 of file lsq_unit.hh.

◆ LSQRequest

template<class Impl >

using LSQUnit< Impl >::LSQRequest = typename Impl::CPUPol::LSQ::LSQRequest

Definition at line 90 of file lsq_unit.hh.

◆ LSQSenderState

template<class Impl >

using LSQUnit< Impl >::LSQSenderState = typename LSQ::LSQSenderState

Definition at line 89 of file lsq_unit.hh.

◆ O3CPU

template<class Impl >

typedef Impl::O3CPU LSQUnit< Impl >::O3CPU

Definition at line 83 of file lsq_unit.hh.

◆ SQIterator

template<class Impl >

typedef CircularQueue<SQEntry>::iterator LSQUnit< Impl >::SQIterator

Definition at line 629 of file lsq_unit.hh.

◆ SQueue

template<class Impl >

typedef CircularQueue<SQEntry> LSQUnit< Impl >::SQueue

Definition at line 631 of file lsq_unit.hh.

◆ StoreQueue

template<class Impl >

using LSQUnit< Impl >::StoreQueue = CircularQueue<SQEntry>

Definition at line 219 of file lsq_unit.hh.

Member Enumeration Documentation

◆ AddrRangeCoverage

template<class Impl >

enum LSQUnit::AddrRangeCoverage

strongprivate

Coverage of one address range with another.

Enumerator
PartialAddrRangeCoverage
FullAddrRangeCoverage
NoAddrRangeCoverage

Definition at line 210 of file lsq_unit.hh.

Constructor & Destructor Documentation

◆ LSQUnit() [1/2]

template<class Impl >

LSQUnit< Impl >::LSQUnit	(	uint32_t	lqEntries,
		uint32_t	sqEntries
	)

Constructs an LSQ unit.

init() must be called prior to use.

Definition at line 204 of file lsq_unit_impl.hh.

◆ LSQUnit() [2/2]

template<class Impl >

LSQUnit< Impl >::LSQUnit ( const LSQUnit< Impl > & l )

inline

We cannot copy LSQUnit because it has stats for which copy contructor is deleted explicitly.

However, STL vector requires a valid copy constructor for the base type at compile time.

Definition at line 229 of file lsq_unit.hh.

References panic.

Member Function Documentation

◆ cacheLineSize()

template<class Impl >

unsigned int LSQUnit< Impl >::cacheLineSize

Definition at line 1293 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::cpu.

◆ checkSnoop()

template<class Impl >

void LSQUnit< Impl >::checkSnoop ( PacketPtr pkt )

Check if an incoming invalidate hits in the lsq on a load that might have issued out of order wrt another load beacuse of the intermediate invalidate.

Definition at line 447 of file lsq_unit_impl.hh.

References CircularQueue< T >::begin(), LSQUnit< Impl >::cacheBlockMask, LSQUnit< Impl >::cpu, DPRINTF, CircularQueue< T >::empty(), CircularQueue< T >::end(), Packet::getAddr(), ArmISA::handleLockedSnoop(), ArmISA::handleLockedSnoopHit(), Packet::isInvalidate(), Request::LLSC, LSQUnit< Impl >::loadQueue, LSQUnit< Impl >::needsTSO, and RiscvISA::x.

◆ checkViolations()

template<class Impl >

Fault LSQUnit< Impl >::checkViolations	(	typename LoadQueue::iterator &	loadIt,
		const DynInstPtr &	inst
	)

Check for ordering violations in the LSQ.

For a store squash if we ever find a conflicting load. For a load, only squash if we an external snoop invalidate has been seen for that load address

Parameters

load_idx	index to start checking at
inst	the instruction to check

Todo:: in theory you only need to check an instruction that has executed however, there isn't a good way in the pipeline at the moment to check all instructions that will execute before the store writes back. Thus, like the implementation that came before it, we're overly conservative.

Definition at line 528 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::depCheckShift, DPRINTF, CircularQueue< T >::end(), LSQUnit< Impl >::loadQueue, LSQUnit< Impl >::memDepViolator, LSQUnit< Impl >::LSQUnitStats::memOrderViolation, NoFault, and LSQUnit< Impl >::stats.

Referenced by LSQUnit< Impl >::executeLoad(), and LSQUnit< Impl >::executeStore().

◆ commitLoad()

template<class Impl >

void LSQUnit< Impl >::commitLoad

Commits the head load.

Definition at line 730 of file lsq_unit_impl.hh.

References DPRINTF, CircularQueue< T >::front(), LSQUnit< Impl >::loadQueue, LSQUnit< Impl >::loads, and CircularQueue< T >::pop_front().

Referenced by LSQUnit< Impl >::commitLoads().

◆ commitLoads()

template<class Impl >

void LSQUnit< Impl >::commitLoads ( InstSeqNum & youngest_inst )

Commits loads older than a specific sequence number.

Definition at line 745 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::commitLoad(), CircularQueue< T >::front(), LSQUnit< Impl >::loadQueue, and LSQUnit< Impl >::loads.

◆ commitStores()

template<class Impl >

void LSQUnit< Impl >::commitStores ( InstSeqNum & youngest_inst )

Commits stores older than a specific sequence number.

Definition at line 757 of file lsq_unit_impl.hh.

References DPRINTF, LSQUnit< Impl >::storeQueue, LSQUnit< Impl >::stores, LSQUnit< Impl >::storesToWB, and RiscvISA::x.

◆ completeDataAccess()

template<class Impl >

void LSQUnit< Impl >::completeDataAccess ( PacketPtr pkt )

Completes the data access that has been returned from the memory system.

Definition at line 111 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::cpu, DPRINTF, FAIL_OTHER, FAIL_REMOTE, FAIL_SELF, Packet::getAddr(), Packet::getHtmTransactionFailedInCacheRC(), Packet::getHtmTransactionUid(), htmFailureToStr(), Packet::htmTransactionFailedInCache(), INVALID, Packet::isHtmTransactional(), Packet::isWrite(), MEMORY, OTHER, panic, Packet::senderState, SIZE, ArmISA::ss, and LSQUnit< Impl >::writeback().

◆ completeStore()

template<class Impl >

void LSQUnit< Impl >::completeStore ( typename StoreQueue::iterator store_idx )

private

Completes the store at the specified index.

Definition at line 1153 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::cpu, curTick(), DPRINTF, DTRACE, CircularQueue< T >::iterator::idx(), LSQUnit< Impl >::iewStage, LSQUnit< Impl >::isStalled(), LSQUnit< Impl >::loadQueue, LSQUnit< Impl >::needsTSO, LSQUnit< Impl >::stalled, LSQUnit< Impl >::stallingLoadIdx, LSQUnit< Impl >::stallingStoreIsn, LSQUnit< Impl >::storeInFlight, LSQUnit< Impl >::storeQueue, LSQUnit< Impl >::stores, and LSQUnit< Impl >::storesToWB.

Referenced by LSQUnit< Impl >::completeDataAccess(), and LSQUnit< Impl >::writebackStores().

◆ drainSanityCheck()

template<class Impl >

void LSQUnit< Impl >::drainSanityCheck

Perform sanity checks after a drain.

Definition at line 295 of file lsq_unit_impl.hh.

References CircularQueue< T >::capacity(), ArmISA::i, LSQUnit< Impl >::loadQueue, LSQUnit< Impl >::retryPkt, and LSQUnit< Impl >::storesToWB.

◆ dTLB()

template<class Impl >

BaseTLB* LSQUnit< Impl >::dTLB ( )

inline

Definition at line 404 of file lsq_unit.hh.

References LSQUnit< Impl >::cpu.

◆ dumpInsts()

template<class Impl >

void LSQUnit< Impl >::dumpInsts

Debugging function to dump instructions in the LSQ.

Definition at line 1268 of file lsq_unit_impl.hh.

References cprintf(), ArmISA::e, LSQUnit< Impl >::loadQueue, LSQUnit< Impl >::loads, LSQUnit< Impl >::storeQueue, and LSQUnit< Impl >::stores.

◆ executeLoad() [1/2]

template<class Impl >

Fault LSQUnit< Impl >::executeLoad ( const DynInstPtr & inst )

Executes a load instruction.

Definition at line 609 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::checkLoads, LSQUnit< Impl >::checkViolations(), DPRINTF, LSQUnit< Impl >::iewStage, and NoFault.

◆ executeLoad() [2/2]

template<class Impl >

Fault LSQUnit< Impl >::executeLoad ( int lq_idx )

inline

Definition at line 275 of file lsq_unit.hh.

References NoFault, and panic.

◆ executeStore()

template<class Impl >

Fault LSQUnit< Impl >::executeStore ( const DynInstPtr & inst )

Executes a store instruction.

Definition at line 677 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::checkViolations(), DPRINTF, NoFault, LSQUnit< Impl >::storeQueue, LSQUnit< Impl >::stores, and LSQUnit< Impl >::storesToWB.

◆ getCount()

template<class Impl >

unsigned LSQUnit< Impl >::getCount ( )

inline

Returns the number of instructions in the LSQ.

Definition at line 351 of file lsq_unit.hh.

References LSQUnit< Impl >::loads, and LSQUnit< Impl >::stores.

◆ getLatestHtmUid()

template<class Impl >

uint64_t LSQUnit< Impl >::getLatestHtmUid ( ) const

inline

Definition at line 321 of file lsq_unit.hh.

References LSQUnit< Impl >::cpu, and LSQUnit< Impl >::lsqID.

◆ getLoadHead()

template<class Impl >

int LSQUnit< Impl >::getLoadHead ( )

inline

Returns the index of the head load instruction.

Definition at line 603 of file lsq_unit.hh.

References CircularQueue< T >::head(), and LSQUnit< Impl >::loadQueue.

◆ getLoadHeadSeqNum()

template<class Impl >

InstSeqNum LSQUnit< Impl >::getLoadHeadSeqNum ( )

inline

Returns the sequence number of the head load instruction.

Definition at line 607 of file lsq_unit.hh.

References CircularQueue< T >::front(), and LSQUnit< Impl >::loadQueue.

◆ getMemDepViolator()

template<class Impl >

Impl::DynInstPtr LSQUnit< Impl >::getMemDepViolator

Returns the memory ordering violator.

Definition at line 413 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::memDepViolator.

◆ getStoreHead()

template<class Impl >

int LSQUnit< Impl >::getStoreHead ( )

inline

Returns the index of the head store instruction.

Definition at line 615 of file lsq_unit.hh.

References LSQUnit< Impl >::storeQueue.

◆ getStoreHeadSeqNum()

template<class Impl >

InstSeqNum LSQUnit< Impl >::getStoreHeadSeqNum ( )

inline

Returns the sequence number of the head store instruction.

Definition at line 618 of file lsq_unit.hh.

References LSQUnit< Impl >::storeQueue.

◆ hasStoresToWB()

template<class Impl >

bool LSQUnit< Impl >::hasStoresToWB ( )

inline

Returns if there are any stores to writeback.

Definition at line 354 of file lsq_unit.hh.

References LSQUnit< Impl >::storesToWB.

◆ init()

template<class Impl >

void LSQUnit< Impl >::init	(	O3CPU *	cpu_ptr,
		IEW *	iew_ptr,
		DerivO3CPUParams *	params,
		LSQ *	lsq_ptr,
		unsigned	id
	)

Initializes the LSQ unit with the specified number of entries.

Definition at line 217 of file lsq_unit_impl.hh.

References csprintf(), DPRINTF, and ArmISA::id.

◆ insert()

template<class Impl >

void LSQUnit< Impl >::insert ( const DynInstPtr & inst )

Inserts an instruction.

Definition at line 313 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::insertLoad(), and LSQUnit< Impl >::insertStore().

◆ insertLoad()

template<class Impl >

void LSQUnit< Impl >::insertLoad ( const DynInstPtr & load_inst )

Inserts a load instruction.

Definition at line 330 of file lsq_unit_impl.hh.

References CircularQueue< T >::advance_tail(), CircularQueue< T >::back(), CircularQueue< T >::capacity(), LSQUnit< Impl >::cpu, DPRINTF, CircularQueue< T >::full(), CircularQueue< T >::getIterator(), LSQUnit< Impl >::htmStarts, LSQUnit< Impl >::htmStops, LSQUnit< Impl >::loadQueue, LSQUnit< Impl >::loads, LSQUnit< Impl >::lsqID, LSQUnit< Impl >::storeQueue, and CircularQueue< T >::tail().

Referenced by LSQUnit< Impl >::insert().

◆ insertStore()

template<class Impl >

void LSQUnit< Impl >::insertStore ( const DynInstPtr & store_inst )

Inserts a store instruction.

Definition at line 392 of file lsq_unit_impl.hh.

References DPRINTF, CircularQueue< T >::end(), LSQUnit< Impl >::loadQueue, CircularQueue< T >::moduloAdd(), LSQUnit< Impl >::storeQueue, LSQUnit< Impl >::stores, and CircularQueue< T >::tail().

Referenced by LSQUnit< Impl >::insert().

◆ isEmpty()

template<class Impl >

bool LSQUnit< Impl >::isEmpty ( ) const

inline

Returns if both the LQ and SQ are empty.

Definition at line 336 of file lsq_unit.hh.

References LSQUnit< Impl >::lqEmpty(), and LSQUnit< Impl >::sqEmpty().

◆ isFull()

template<class Impl >

bool LSQUnit< Impl >::isFull ( )

inline

Returns if either the LQ or SQ is full.

Definition at line 333 of file lsq_unit.hh.

References LSQUnit< Impl >::lqFull(), and LSQUnit< Impl >::sqFull().

◆ isStalled()

template<class Impl >

bool LSQUnit< Impl >::isStalled ( )

inline

Returns whether or not the LSQ unit is stalled.

Definition at line 626 of file lsq_unit.hh.

References LSQUnit< Impl >::stalled.

Referenced by LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::squash(), and LSQUnit< Impl >::storePostSend().

◆ lqEmpty()

template<class Impl >

bool LSQUnit< Impl >::lqEmpty ( ) const

inline

Returns if the LQ is empty.

Definition at line 345 of file lsq_unit.hh.

References LSQUnit< Impl >::loads.

Referenced by LSQUnit< Impl >::isEmpty().

◆ lqFull()

template<class Impl >

bool LSQUnit< Impl >::lqFull ( )

inline

Returns if the LQ is full.

Definition at line 339 of file lsq_unit.hh.

References CircularQueue< T >::full(), and LSQUnit< Impl >::loadQueue.

Referenced by LSQUnit< Impl >::isFull().

◆ name()

template<class Impl >

std::string LSQUnit< Impl >::name

Returns the name of the LSQ unit.

Definition at line 261 of file lsq_unit_impl.hh.

References sc_dt::to_string().

◆ numFreeLoadEntries()

template<class Impl >

unsigned LSQUnit< Impl >::numFreeLoadEntries

Returns the number of free LQ entries.

Definition at line 424 of file lsq_unit_impl.hh.

References CircularQueue< T >::capacity(), DPRINTF, LSQUnit< Impl >::loadQueue, and LSQUnit< Impl >::loads.

◆ numFreeStoreEntries()

template<class Impl >

unsigned LSQUnit< Impl >::numFreeStoreEntries

Returns the number of free SQ entries.

Definition at line 435 of file lsq_unit_impl.hh.

References DPRINTF, LSQUnit< Impl >::storeQueue, and LSQUnit< Impl >::stores.

◆ numHtmStarts()

template<class Impl >

int LSQUnit< Impl >::numHtmStarts ( ) const

inline

Definition at line 318 of file lsq_unit.hh.

References LSQUnit< Impl >::htmStarts.

◆ numHtmStops()

template<class Impl >

int LSQUnit< Impl >::numHtmStops ( ) const

inline

Definition at line 319 of file lsq_unit.hh.

References LSQUnit< Impl >::htmStops.

◆ numLoads()

template<class Impl >

int LSQUnit< Impl >::numLoads ( )

inline

Returns the number of loads in the LQ.

Definition at line 312 of file lsq_unit.hh.

References LSQUnit< Impl >::loads.

◆ numStores()

template<class Impl >

int LSQUnit< Impl >::numStores ( )

inline

Returns the number of stores in the SQ.

Definition at line 315 of file lsq_unit.hh.

References LSQUnit< Impl >::stores.

◆ numStoresToWB()

template<class Impl >

int LSQUnit< Impl >::numStoresToWB ( )

inline

Returns the number of stores to writeback.

Definition at line 357 of file lsq_unit.hh.

References LSQUnit< Impl >::storesToWB.

◆ read()

template<class Impl >

Fault LSQUnit< Impl >::read	(	LSQRequest *	req,
		int	load_idx
	)

Executes the load at the given index.

Definition at line 636 of file lsq_unit.hh.

References curTick(), Packet::dataStatic(), DPRINTF, Packet::getAddr(), ArmISA::handleLockedRead(), LSQUnit< Impl >::LSQEntry::instruction(), Packet::makeResponse(), Request::NO_ACCESS, NoFault, panic, MemCmd::ReadReq, Packet::req, Packet::setHtmTransactional(), and LSQUnit< Impl >::LSQEntry::setRequest().

◆ recvRetry()

template<class Impl >

void LSQUnit< Impl >::recvRetry

Handles doing the retry.

Definition at line 1258 of file lsq_unit_impl.hh.

References DPRINTF, LSQUnit< Impl >::isStoreBlocked, and LSQUnit< Impl >::writebackBlockedStore().

◆ recvTimingResp()

template<class Impl >

bool LSQUnit< Impl >::recvTimingResp ( PacketPtr pkt )

Handles writing back and completing the load or store that has returned from memory.

Parameters

pkt	Response packet from the memory sub-system

Definition at line 93 of file lsq_unit_impl.hh.

References Packet::senderState.

◆ resetHtmStartsStops()

template<class Impl >

void LSQUnit< Impl >::resetHtmStartsStops ( )

inline

Definition at line 320 of file lsq_unit.hh.

References LSQUnit< Impl >::htmStarts, and LSQUnit< Impl >::htmStops.

◆ resetState()

template<class Impl >

void LSQUnit< Impl >::resetState

private

Reset the LSQ state.

Definition at line 241 of file lsq_unit_impl.hh.

Referenced by LSQUnit< Impl >::takeOverFrom().

◆ schedule()

template<class Impl >

void LSQUnit< Impl >::schedule	(	Event &	ev,
		Tick	when
	)

inline

Schedule event for the cpu.

Definition at line 402 of file lsq_unit.hh.

References LSQUnit< Impl >::cpu.

◆ setDcachePort()

template<class Impl >

void LSQUnit< Impl >::setDcachePort ( RequestPort * dcache_port )

Sets the pointer to the dcache port.

Definition at line 288 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::dcachePort.

◆ setLastRetiredHtmUid()

template<class Impl >

void LSQUnit< Impl >::setLastRetiredHtmUid ( uint64_t htm_uid )

inline

Definition at line 326 of file lsq_unit.hh.

References LSQUnit< Impl >::lastRetiredHtmUid.

◆ sqEmpty()

template<class Impl >

bool LSQUnit< Impl >::sqEmpty ( ) const

inline

Returns if the SQ is empty.

Definition at line 348 of file lsq_unit.hh.

References LSQUnit< Impl >::stores.

Referenced by LSQUnit< Impl >::isEmpty().

◆ sqFull()

template<class Impl >

bool LSQUnit< Impl >::sqFull ( )

inline

Returns if the SQ is full.

Definition at line 342 of file lsq_unit.hh.

References LSQUnit< Impl >::storeQueue.

Referenced by LSQUnit< Impl >::isFull().

◆ squash()

template<class Impl >

void LSQUnit< Impl >::squash ( const InstSeqNum & squashed_num )

◆ storePostSend()

template<class Impl >

void LSQUnit< Impl >::storePostSend

private

Handles completing the send of a store to memory.

Definition at line 1059 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::cpu, DPRINTF, LSQUnit< Impl >::iewStage, LSQUnit< Impl >::isStalled(), LSQUnit< Impl >::loadQueue, LSQUnit< Impl >::needsTSO, LSQUnit< Impl >::stalled, LSQUnit< Impl >::stallingLoadIdx, LSQUnit< Impl >::stallingStoreIsn, LSQUnit< Impl >::storeInFlight, and LSQUnit< Impl >::storeWBIt.

Referenced by LSQUnit< Impl >::writebackBlockedStore(), and LSQUnit< Impl >::writebackStores().

◆ takeOverFrom()

template<class Impl >

void LSQUnit< Impl >::takeOverFrom

Takes over from another CPU's thread.

Definition at line 306 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::resetState().

◆ trySendPacket()

template<class Impl >

bool LSQUnit< Impl >::trySendPacket	(	bool	isLoad,
		PacketPtr	data_pkt
	)

Attempts to send a packet to the cache.

Check if there are ports available. Return true if there are, false if there are not.

Definition at line 1218 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::LSQUnitStats::blockedByCache, LSQ< Impl >::cacheBlocked(), LSQ< Impl >::cachePortAvailable(), LSQ< Impl >::cachePortBusy(), LSQUnit< Impl >::dcachePort, LSQUnit< Impl >::isStoreBlocked, LSQUnit< Impl >::lsq, Packet::senderState, RequestPort::sendTimingReq(), LSQUnit< Impl >::stats, and LSQUnit< Impl >::storeWBIt.

◆ violation()

template<class Impl >

bool LSQUnit< Impl >::violation ( )

inline

Returns if there is a memory ordering violation.

Value is reset upon call to getMemDepViolator().

Definition at line 300 of file lsq_unit.hh.

References LSQUnit< Impl >::memDepViolator.

◆ willWB()

template<class Impl >

bool LSQUnit< Impl >::willWB ( )

inline

Returns if the LSQ unit will writeback on this cycle.

Definition at line 361 of file lsq_unit.hh.

References CircularQueue< T >::iterator::dereferenceable(), LSQUnit< Impl >::isStoreBlocked, and LSQUnit< Impl >::storeWBIt.

◆ write()

template<class Impl >

Fault LSQUnit< Impl >::write	(	LSQRequest *	req,
		uint8_t *	data,
		int	store_idx
	)

Executes the store at the given index.

Definition at line 959 of file lsq_unit.hh.

References Request::CACHE_BLOCK_ZERO, data, DPRINTF, NoFault, and Request::STORE_NO_DATA.

◆ writeback()

template<class Impl >

void LSQUnit< Impl >::writeback	(	const DynInstPtr &	inst,
		PacketPtr	pkt
	)

private

Writes back the instruction, sending it to IEW.

Definition at line 1091 of file lsq_unit_impl.hh.

References DPRINTF, htmFailureToStr(), Packet::htmTransactionFailedInCache(), LSQUnit< Impl >::iewStage, LSQUnit< Impl >::LSQUnitStats::ignoredResponses, NoFault, and LSQUnit< Impl >::stats.

Referenced by LSQUnit< Impl >::completeDataAccess().

◆ writebackBlockedStore()

template<class Impl >

void LSQUnit< Impl >::writebackBlockedStore

private

Try to finish a previously blocked write back attempt.

Definition at line 784 of file lsq_unit_impl.hh.

References LSQUnit< Impl >::isStoreBlocked, LSQUnit< Impl >::storePostSend(), and LSQUnit< Impl >::storeWBIt.

Referenced by LSQUnit< Impl >::recvRetry(), and LSQUnit< Impl >::writebackStores().

◆ writebackStores()

template<class Impl >

void LSQUnit< Impl >::writebackStores

Member Data Documentation

◆ cacheBlockMask

template<class Impl >

Addr LSQUnit< Impl >::cacheBlockMask

private

Address Mask for a cache block (e.g.

~(cache_block_size-1))

Definition at line 529 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::checkSnoop(), and LSQUnit< Impl >::writebackStores().

◆ checkLoads

template<class Impl >

bool LSQUnit< Impl >::checkLoads

private

Should loads be checked for dependency issues.

Definition at line 507 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::executeLoad().

◆ cpu

template<class Impl >

O3CPU* LSQUnit< Impl >::cpu

private

Pointer to the CPU.

Definition at line 408 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::cacheLineSize(), LSQUnit< Impl >::checkSnoop(), LSQUnit< Impl >::completeDataAccess(), LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::dTLB(), LSQUnit< Impl >::getLatestHtmUid(), LSQUnit< Impl >::insertLoad(), LSQUnit< Impl >::schedule(), LSQUnit< Impl >::squash(), LSQUnit< Impl >::storePostSend(), and LSQUnit< Impl >::writebackStores().

◆ dcachePort

template<class Impl >

RequestPort* LSQUnit< Impl >::dcachePort

private

Pointer to the dcache port.

Used only for sending.

Definition at line 417 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::setDcachePort(), and LSQUnit< Impl >::trySendPacket().

◆ depCheckShift

template<class Impl >

unsigned LSQUnit< Impl >::depCheckShift

private

The number of places to shift addresses in the LSQ before checking for dependency violations.

Definition at line 504 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::checkViolations().

◆ fromIssue

template<class Impl >

TimeBuffer<IssueStruct>::wire LSQUnit< Impl >::fromIssue

private

Wire to read information from the issue stage time queue.

Definition at line 532 of file lsq_unit.hh.

◆ hasPendingRequest

template<class Impl >

bool LSQUnit< Impl >::hasPendingRequest

private

Whether or not there is a packet that couldn't be sent because of a lack of cache ports.

Definition at line 557 of file lsq_unit.hh.

◆ htmStarts

template<class Impl >

int LSQUnit< Impl >::htmStarts

private

Definition at line 518 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::insertLoad(), LSQUnit< Impl >::numHtmStarts(), LSQUnit< Impl >::resetHtmStartsStops(), and LSQUnit< Impl >::squash().

◆ htmStops

template<class Impl >

int LSQUnit< Impl >::htmStops

private

Definition at line 519 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::insertLoad(), LSQUnit< Impl >::numHtmStops(), LSQUnit< Impl >::resetHtmStartsStops(), and LSQUnit< Impl >::squash().

◆ iewStage

template<class Impl >

IEW* LSQUnit< Impl >::iewStage

private

Pointer to the IEW stage.

Definition at line 411 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::executeLoad(), LSQUnit< Impl >::storePostSend(), and LSQUnit< Impl >::writeback().

◆ isStoreBlocked

template<class Impl >

bool LSQUnit< Impl >::isStoreBlocked

private

Whehter or not a store is blocked due to the memory system.

Definition at line 547 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::recvRetry(), LSQUnit< Impl >::trySendPacket(), LSQUnit< Impl >::willWB(), LSQUnit< Impl >::writebackBlockedStore(), and LSQUnit< Impl >::writebackStores().

◆ lastRetiredHtmUid

template<class Impl >

uint64_t LSQUnit< Impl >::lastRetiredHtmUid

private

Definition at line 521 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::setLastRetiredHtmUid(), and LSQUnit< Impl >::squash().

◆ loadQueue

template<class Impl >

LoadQueue LSQUnit< Impl >::loadQueue

The load queue.

Definition at line 498 of file lsq_unit.hh.

◆ loads

template<class Impl >

int LSQUnit< Impl >::loads

private

The number of load instructions in the LQ.

Definition at line 510 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::commitLoad(), LSQUnit< Impl >::commitLoads(), LSQUnit< Impl >::dumpInsts(), LSQUnit< Impl >::getCount(), LSQUnit< Impl >::insertLoad(), LSQUnit< Impl >::lqEmpty(), LSQUnit< Impl >::numFreeLoadEntries(), LSQUnit< Impl >::numLoads(), and LSQUnit< Impl >::squash().

◆ lsq

template<class Impl >

LSQ* LSQUnit< Impl >::lsq

private

Pointer to the LSQ.

Definition at line 414 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::trySendPacket(), and LSQUnit< Impl >::writebackStores().

◆ lsqID

template<class Impl >

ThreadID LSQUnit< Impl >::lsqID

private

The LSQUnit thread id.

Definition at line 492 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::getLatestHtmUid(), LSQUnit< Impl >::insertLoad(), LSQUnit< Impl >::squash(), and LSQUnit< Impl >::writebackStores().

◆ MaxDataBytes

template<class Impl >

constexpr auto LSQUnit< Impl >::MaxDataBytes = MaxVecRegLenInBytes

staticconstexpr

Definition at line 81 of file lsq_unit.hh.

◆ memDepViolator

template<class Impl >

DynInstPtr LSQUnit< Impl >::memDepViolator

private

The oldest load that caused a memory ordering violation.

Definition at line 553 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::checkViolations(), LSQUnit< Impl >::getMemDepViolator(), LSQUnit< Impl >::squash(), and LSQUnit< Impl >::violation().

◆ needsTSO

template<class Impl >

bool LSQUnit< Impl >::needsTSO

private

Flag for memory model.

Definition at line 563 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::checkSnoop(), LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::storePostSend(), and LSQUnit< Impl >::writebackStores().

◆ pendingRequest

template<class Impl >

LSQRequest* LSQUnit< Impl >::pendingRequest

private

The packet that is pending free cache ports.

Definition at line 560 of file lsq_unit.hh.

◆ retryPkt

template<class Impl >

PacketPtr LSQUnit< Impl >::retryPkt

private

The packet that needs to be retried.

Definition at line 544 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::drainSanityCheck().

◆ stalled

template<class Impl >

bool LSQUnit< Impl >::stalled

private

Whether or not the LSQ is stalled.

Definition at line 535 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::isStalled(), LSQUnit< Impl >::squash(), and LSQUnit< Impl >::storePostSend().

◆ stallingLoadIdx

template<class Impl >

int LSQUnit< Impl >::stallingLoadIdx

private

The index of the above store.

Definition at line 541 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::squash(), and LSQUnit< Impl >::storePostSend().

◆ stallingStoreIsn

template<class Impl >

InstSeqNum LSQUnit< Impl >::stallingStoreIsn

private

The store that causes the stall due to partial store to load forwarding.

Definition at line 539 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::squash(), and LSQUnit< Impl >::storePostSend().

◆ stats

template<class Impl >

LSQUnit::LSQUnitStats LSQUnit< Impl >::stats

protected

Referenced by LSQUnit< Impl >::checkViolations(), LSQUnit< Impl >::squash(), LSQUnit< Impl >::trySendPacket(), and LSQUnit< Impl >::writeback().

◆ storeInFlight

template<class Impl >

bool LSQUnit< Impl >::storeInFlight

private

Whether or not a store is in flight.

Definition at line 550 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::storePostSend(), and LSQUnit< Impl >::writebackStores().

◆ storeQueue

template<class Impl >

CircularQueue<SQEntry> LSQUnit< Impl >::storeQueue

The store queue.

Definition at line 495 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::commitStores(), LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::dumpInsts(), LSQUnit< Impl >::executeStore(), LSQUnit< Impl >::getStoreHead(), LSQUnit< Impl >::getStoreHeadSeqNum(), LSQUnit< Impl >::insertLoad(), LSQUnit< Impl >::insertStore(), LSQ< Impl >::LSQRequest::install(), LSQUnit< Impl >::numFreeStoreEntries(), LSQUnit< Impl >::sqFull(), LSQUnit< Impl >::squash(), and LSQUnit< Impl >::writebackStores().

◆ stores

template<class Impl >

int LSQUnit< Impl >::stores

private

The number of store instructions in the SQ.

Definition at line 512 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::commitStores(), LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::dumpInsts(), LSQUnit< Impl >::executeStore(), LSQUnit< Impl >::getCount(), LSQUnit< Impl >::insertStore(), LSQUnit< Impl >::numFreeStoreEntries(), LSQUnit< Impl >::numStores(), LSQUnit< Impl >::sqEmpty(), LSQUnit< Impl >::squash(), and LSQUnit< Impl >::writebackStores().

◆ storesToWB

template<class Impl >

int LSQUnit< Impl >::storesToWB

private

The number of store instructions in the SQ waiting to writeback.

Definition at line 514 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::commitStores(), LSQUnit< Impl >::completeStore(), LSQUnit< Impl >::drainSanityCheck(), LSQUnit< Impl >::executeStore(), LSQUnit< Impl >::hasStoresToWB(), LSQUnit< Impl >::numStoresToWB(), and LSQUnit< Impl >::writebackStores().

◆ storeWBIt

template<class Impl >

StoreQueue::iterator LSQUnit< Impl >::storeWBIt

private

The index of the first instruction that may be ready to be written back, and has not yet been written back.

Definition at line 526 of file lsq_unit.hh.

Referenced by LSQUnit< Impl >::storePostSend(), LSQUnit< Impl >::trySendPacket(), LSQUnit< Impl >::willWB(), LSQUnit< Impl >::writebackBlockedStore(), and LSQUnit< Impl >::writebackStores().

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

cpu/o3/lsq_unit.hh
cpu/o3/lsq_unit_impl.hh

Classes

Public Types

Public Member Functions

Public Attributes

Static Public Attributes

Protected Attributes

Private Types

Private Member Functions

Private Attributes

Detailed Description

template<class Impl> class LSQUnit< Impl >

Member Typedef Documentation

◆ DynInstPtr

◆ IEW

◆ IssueStruct

◆ LoadQueue

◆ LQEntry

◆ LQIterator

◆ LQueue

◆ LSQ

◆ LSQRequest

◆ LSQSenderState

◆ O3CPU

◆ SQIterator

◆ SQueue

◆ StoreQueue

Member Enumeration Documentation

◆ AddrRangeCoverage

Constructor & Destructor Documentation

◆ LSQUnit() [1/2]

◆ LSQUnit() [2/2]

Member Function Documentation

◆ cacheLineSize()

◆ checkSnoop()

◆ checkViolations()

◆ commitLoad()

◆ commitLoads()

◆ commitStores()

◆ completeDataAccess()

◆ completeStore()

◆ drainSanityCheck()

◆ dTLB()

◆ dumpInsts()

◆ executeLoad() [1/2]

◆ executeLoad() [2/2]

◆ executeStore()

◆ getCount()

◆ getLatestHtmUid()

◆ getLoadHead()

◆ getLoadHeadSeqNum()

◆ getMemDepViolator()

◆ getStoreHead()

◆ getStoreHeadSeqNum()

◆ hasStoresToWB()

◆ init()

◆ insert()

◆ insertLoad()

◆ insertStore()

◆ isEmpty()

◆ isFull()

◆ isStalled()

◆ lqEmpty()

◆ lqFull()

◆ name()

◆ numFreeLoadEntries()

◆ numFreeStoreEntries()

◆ numHtmStarts()

◆ numHtmStops()

◆ numLoads()

◆ numStores()

◆ numStoresToWB()

◆ read()

◆ recvRetry()

◆ recvTimingResp()

◆ resetHtmStartsStops()

◆ resetState()

◆ schedule()

◆ setDcachePort()

◆ setLastRetiredHtmUid()

◆ sqEmpty()

template<class Impl>
class LSQUnit< Impl >