DefaultFetch class handles both single threaded and SMT fetch. More...

#include <fetch.hh>

Classes
class	FetchTranslation

class	FinishTranslationEvent

class	IcachePort
	IcachePort class for instruction fetch. More...

struct	Stalls
	Source of possible stalls. More...

Public Types
enum	FetchStatus { Active, Inactive }
	Overall fetch status. More...

enum	ThreadStatus { Running, Idle, Squashing, Blocked, Fetching, TrapPending, QuiescePending, ItlbWait, IcacheWaitResponse, IcacheWaitRetry, IcacheAccessComplete, NoGoodAddr }
	Individual thread status. More...

typedef Impl::CPUPol	CPUPol
	Typedefs from Impl. More...

typedef Impl::DynInst	DynInst

typedef Impl::DynInstPtr	DynInstPtr

typedef Impl::O3CPU	O3CPU

typedef CPUPol::FetchStruct	FetchStruct
	Typedefs from the CPU policy. More...

typedef CPUPol::TimeStruct	TimeStruct

typedef TheISA::MachInst	MachInst
	Typedefs from ISA. More...

Public Member Functions
	DefaultFetch (O3CPU _cpu, DerivO3CPUParams params)
	DefaultFetch constructor. More...

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

void	regStats ()
	Registers statistics. More...

void	regProbePoints ()
	Registers probes. More...

void	setTimeBuffer (TimeBuffer< TimeStruct > *time_buffer)
	Sets the main backwards communication time buffer pointer. More...

void	setActiveThreads (std::list< ThreadID > *at_ptr)
	Sets pointer to list of active threads. More...

void	setFetchQueue (TimeBuffer< FetchStruct > *fq_ptr)
	Sets pointer to time buffer used to communicate to the next stage. More...

void	startupStage ()
	Initialize stage. More...

void	clearStates (ThreadID tid)
	Clear all thread-specific states. More...

void	recvReqRetry ()
	Handles retrying the fetch access. More...

void	processCacheCompletion (PacketPtr pkt)
	Processes cache completion event. More...

void	drainResume ()
	Resume after a drain. More...

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

bool	isDrained () const
	Has the stage drained? More...

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

void	drainStall (ThreadID tid)
	Stall the fetch stage after reaching a safe drain point. More...

void	wakeFromQuiesce ()
	Tells fetch to wake up from a quiesce instruction. More...

void	deactivateThread (ThreadID tid)
	For priority-based fetch policies, need to keep update priorityList. More...

void	squash (const TheISA::PCState &newPC, const InstSeqNum seq_num, DynInstPtr squashInst, ThreadID tid)
	Squashes a specific thread and resets the PC. More...

void	tick ()
	Ticks the fetch stage, processing all inputs signals and fetching as many instructions as possible. More...

bool	checkSignalsAndUpdate (ThreadID tid)
	Checks all input signals and updates the status as necessary. More...

void	fetch (bool &status_change)
	Does the actual fetching of instructions and passing them on to the next stage. More...

Addr	fetchBufferAlignPC (Addr addr)
	Align a PC to the start of a fetch buffer block. More...

MasterPort &	getInstPort ()

Public Attributes
TheISA::Decoder *	decoder [Impl::MaxThreads]
	The decoder. More...

Private Member Functions
void	resetStage ()
	Reset this pipeline stage. More...

void	switchToActive ()
	Changes the status of this stage to active, and indicates this to the CPU. More...

void	switchToInactive ()
	Changes the status of this stage to inactive, and indicates this to the CPU. More...

bool	lookupAndUpdateNextPC (const DynInstPtr &inst, TheISA::PCState &pc)
	Looks up in the branch predictor to see if the next PC should be either next PC+=MachInst or a branch target. More...

bool	fetchCacheLine (Addr vaddr, ThreadID tid, Addr pc)
	Fetches the cache line that contains the fetch PC. More...

void	finishTranslation (const Fault &fault, const RequestPtr &mem_req)

bool	checkInterrupt (Addr pc)
	Check if an interrupt is pending and that we need to handle. More...

void	doSquash (const TheISA::PCState &newPC, const DynInstPtr squashInst, ThreadID tid)
	Squashes a specific thread and resets the PC. More...

void	squashFromDecode (const TheISA::PCState &newPC, const DynInstPtr squashInst, const InstSeqNum seq_num, ThreadID tid)
	Squashes a specific thread and resets the PC. More...

bool	checkStall (ThreadID tid) const
	Checks if a thread is stalled. More...

FetchStatus	updateFetchStatus ()
	Updates overall fetch stage status; to be called at the end of each cycle. More...

DynInstPtr	buildInst (ThreadID tid, StaticInstPtr staticInst, StaticInstPtr curMacroop, TheISA::PCState thisPC, TheISA::PCState nextPC, bool trace)

ThreadID	getFetchingThread ()
	Returns the appropriate thread to fetch, given the fetch policy. More...

ThreadID	roundRobin ()
	Returns the appropriate thread to fetch using a round robin policy. More...

ThreadID	iqCount ()
	Returns the appropriate thread to fetch using the IQ count policy. More...

ThreadID	lsqCount ()
	Returns the appropriate thread to fetch using the LSQ count policy. More...

ThreadID	branchCount ()
	Returns the appropriate thread to fetch using the branch count policy. More...

void	pipelineIcacheAccesses (ThreadID tid)
	Pipeline the next I-cache access to the current one. More...

void	profileStall (ThreadID tid)
	Profile the reasons of fetch stall. More...

Private Attributes
FetchStatus	_status
	Fetch status. More...

ThreadStatus	fetchStatus [Impl::MaxThreads]
	Per-thread status. More...

FetchPolicy	fetchPolicy
	Fetch policy. More...

std::list< ThreadID >	priorityList
	List that has the threads organized by priority. More...

ProbePointArg< DynInstPtr > *	ppFetch
	Probe points. More...

ProbePointArg< RequestPtr > *	ppFetchRequestSent
	To probe when a fetch request is successfully sent. More...

O3CPU *	cpu
	Pointer to the O3CPU. More...

TimeBuffer< TimeStruct > *	timeBuffer
	Time buffer interface. More...

TimeBuffer< TimeStruct >::wire	fromDecode
	Wire to get decode's information from backwards time buffer. More...

TimeBuffer< TimeStruct >::wire	fromRename
	Wire to get rename's information from backwards time buffer. More...

TimeBuffer< TimeStruct >::wire	fromIEW
	Wire to get iew's information from backwards time buffer. More...

TimeBuffer< TimeStruct >::wire	fromCommit
	Wire to get commit's information from backwards time buffer. More...

TimeBuffer< FetchStruct >::wire	toDecode
	Wire used to write any information heading to decode. More...

BPredUnit *	branchPred
	BPredUnit. More...

TheISA::PCState	pc [Impl::MaxThreads]

Addr	fetchOffset [Impl::MaxThreads]

StaticInstPtr	macroop [Impl::MaxThreads]

bool	delayedCommit [Impl::MaxThreads]
	Can the fetch stage redirect from an interrupt on this instruction? More...

RequestPtr	memReq [Impl::MaxThreads]
	Memory request used to access cache. More...

bool	wroteToTimeBuffer
	Variable that tracks if fetch has written to the time buffer this cycle. More...

int	numInst
	Tracks how many instructions has been fetched this cycle. More...

Stalls	stalls [Impl::MaxThreads]
	Tracks which stages are telling fetch to stall. More...

Cycles	decodeToFetchDelay
	Decode to fetch delay. More...

Cycles	renameToFetchDelay
	Rename to fetch delay. More...

Cycles	iewToFetchDelay
	IEW to fetch delay. More...

Cycles	commitToFetchDelay
	Commit to fetch delay. More...

unsigned	fetchWidth
	The width of fetch in instructions. More...

unsigned	decodeWidth
	The width of decode in instructions. More...

bool	cacheBlocked
	Is the cache blocked? If so no threads can access it. More...

PacketPtr	retryPkt
	The packet that is waiting to be retried. More...

ThreadID	retryTid
	The thread that is waiting on the cache to tell fetch to retry. More...

unsigned int	cacheBlkSize
	Cache block size. More...

unsigned	fetchBufferSize
	The size of the fetch buffer in bytes. More...

Addr	fetchBufferMask
	Mask to align a fetch address to a fetch buffer boundary. More...

uint8_t *	fetchBuffer [Impl::MaxThreads]
	The fetch data that is being fetched and buffered. More...

Addr	fetchBufferPC [Impl::MaxThreads]
	The PC of the first instruction loaded into the fetch buffer. More...

unsigned	fetchQueueSize
	The size of the fetch queue in micro-ops. More...

std::deque< DynInstPtr >	fetchQueue [Impl::MaxThreads]
	Queue of fetched instructions. More...

bool	fetchBufferValid [Impl::MaxThreads]
	Whether or not the fetch buffer data is valid. More...

int	instSize
	Size of instructions. More...

Counter	lastIcacheStall [Impl::MaxThreads]
	Icache stall statistics. More...

std::list< ThreadID > *	activeThreads
	List of Active Threads. More...

ThreadID	numThreads
	Number of threads. More...

ThreadID	numFetchingThreads
	Number of threads that are actively fetching. More...

ThreadID	threadFetched
	Thread ID being fetched. More...

bool	interruptPending
	Checks if there is an interrupt pending. More...

IcachePort	icachePort
	Instruction port. More...

bool	issuePipelinedIfetch [Impl::MaxThreads]
	Set to true if a pipelined I-cache request should be issued. More...

FinishTranslationEvent	finishTranslationEvent
	Event used to delay fault generation of translation faults. More...

Stats::Scalar	icacheStallCycles
	Stat for total number of cycles stalled due to an icache miss. More...

Stats::Scalar	fetchedInsts
	Stat for total number of fetched instructions. More...

Stats::Scalar	fetchedBranches
	Total number of fetched branches. More...

Stats::Scalar	predictedBranches
	Stat for total number of predicted branches. More...

Stats::Scalar	fetchCycles
	Stat for total number of cycles spent fetching. More...

Stats::Scalar	fetchSquashCycles
	Stat for total number of cycles spent squashing. More...

Stats::Scalar	fetchTlbCycles
	Stat for total number of cycles spent waiting for translation. More...

Stats::Scalar	fetchIdleCycles
	Stat for total number of cycles spent blocked due to other stages in the pipeline. More...

Stats::Scalar	fetchBlockedCycles
	Total number of cycles spent blocked. More...

Stats::Scalar	fetchMiscStallCycles
	Total number of cycles spent in any other state. More...

Stats::Scalar	fetchPendingDrainCycles
	Total number of cycles spent in waiting for drains. More...

Stats::Scalar	fetchNoActiveThreadStallCycles
	Total number of stall cycles caused by no active threads to run. More...

Stats::Scalar	fetchPendingTrapStallCycles
	Total number of stall cycles caused by pending traps. More...

Stats::Scalar	fetchPendingQuiesceStallCycles
	Total number of stall cycles caused by pending quiesce instructions. More...

Stats::Scalar	fetchIcacheWaitRetryStallCycles
	Total number of stall cycles caused by I-cache wait retrys. More...

Stats::Scalar	fetchedCacheLines
	Stat for total number of fetched cache lines. More...

Stats::Scalar	fetchIcacheSquashes
	Total number of outstanding icache accesses that were dropped due to a squash. More...

Stats::Scalar	fetchTlbSquashes
	Total number of outstanding tlb accesses that were dropped due to a squash. More...

Stats::Distribution	fetchNisnDist
	Distribution of number of instructions fetched each cycle. More...

Stats::Formula	idleRate
	Rate of how often fetch was idle. More...

Stats::Formula	branchRate
	Number of branch fetches per cycle. More...

Stats::Formula	fetchRate
	Number of instruction fetched per cycle. More...

Detailed Description

template<class Impl>
class DefaultFetch< Impl >

DefaultFetch class handles both single threaded and SMT fetch.

Its width is specified by the parameters; each cycle it tries to fetch that many instructions. It supports using a branch predictor to predict direction and targets. It supports the idling functionality of the CPU by indicating to the CPU when it is active and inactive.

Definition at line 74 of file fetch.hh.

Member Typedef Documentation

◆ CPUPol

template<class Impl>

typedef Impl::CPUPol DefaultFetch< Impl >::CPUPol

Typedefs from Impl.

Definition at line 78 of file fetch.hh.

◆ DynInst

template<class Impl>

typedef Impl::DynInst DefaultFetch< Impl >::DynInst

Definition at line 79 of file fetch.hh.

◆ DynInstPtr

template<class Impl>

typedef Impl::DynInstPtr DefaultFetch< Impl >::DynInstPtr

Definition at line 80 of file fetch.hh.

◆ FetchStruct

template<class Impl>

typedef CPUPol::FetchStruct DefaultFetch< Impl >::FetchStruct

Typedefs from the CPU policy.

Definition at line 84 of file fetch.hh.

◆ MachInst

template<class Impl>

typedef TheISA::MachInst DefaultFetch< Impl >::MachInst

Typedefs from ISA.

Definition at line 88 of file fetch.hh.

◆ O3CPU

template<class Impl>

typedef Impl::O3CPU DefaultFetch< Impl >::O3CPU

Definition at line 81 of file fetch.hh.

◆ TimeStruct

template<class Impl>

typedef CPUPol::TimeStruct DefaultFetch< Impl >::TimeStruct

Definition at line 85 of file fetch.hh.

Member Enumeration Documentation

◆ FetchStatus

template<class Impl>

enum DefaultFetch::FetchStatus

Overall fetch status.

Used to determine if the CPU can deschedule itsef due to a lack of activity.

Enumerator
Active
Inactive

Definition at line 182 of file fetch.hh.

◆ ThreadStatus

template<class Impl>

enum DefaultFetch::ThreadStatus

Individual thread status.

Enumerator
Running
Idle
Squashing
Blocked
Fetching
TrapPending
QuiescePending
ItlbWait
IcacheWaitResponse
IcacheWaitRetry
IcacheAccessComplete
NoGoodAddr

Definition at line 188 of file fetch.hh.

Constructor & Destructor Documentation

◆ DefaultFetch()

template<class Impl >

DefaultFetch< Impl >::DefaultFetch	(	O3CPU *	_cpu,
		DerivO3CPUParams *	params
	)

DefaultFetch constructor.

Definition at line 83 of file fetch_impl.hh.

Member Function Documentation

◆ branchCount()

template<class Impl >

ThreadID DefaultFetch< Impl >::branchCount ( )

private

Returns the appropriate thread to fetch using the branch count policy.

Definition at line 1590 of file fetch_impl.hh.

References InvalidThreadID, and panic.

Referenced by DefaultFetch< Impl >::getFetchingThread(), and DefaultFetch< Impl >::getInstPort().

◆ buildInst()

template<class Impl >

Impl::DynInstPtr DefaultFetch< Impl >::buildInst	(	ThreadID	tid,
		StaticInstPtr	staticInst,
		StaticInstPtr	curMacroop,
		TheISA::PCState	thisPC,
		TheISA::PCState	nextPC,
		bool	trace
	)

private

Definition at line 1104 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu, curTick(), DefaultFetch< Impl >::delayedCommit, DPRINTF, DefaultFetch< Impl >::fetchQueue, DefaultFetch< Impl >::fetchQueueSize, DefaultFetch< Impl >::fetchWidth, and DefaultFetch< Impl >::numInst.

Referenced by DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::finishTranslation(), and DefaultFetch< Impl >::getInstPort().

◆ checkInterrupt()

template<class Impl>

bool DefaultFetch< Impl >::checkInterrupt ( Addr pc )

inlineprivate

Check if an interrupt is pending and that we need to handle.

Definition at line 326 of file fetch.hh.

References DefaultFetch< Impl >::checkSignalsAndUpdate(), DefaultFetch< Impl >::checkStall(), DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::IcachePort::fetch, DefaultFetch< Impl >::interruptPending, DefaultFetch< Impl >::squash(), DefaultFetch< Impl >::squashFromDecode(), DefaultFetch< Impl >::tick(), and DefaultFetch< Impl >::updateFetchStatus().

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::fetchCacheLine().

◆ checkSignalsAndUpdate()

template<class Impl >

bool DefaultFetch< Impl >::checkSignalsAndUpdate ( ThreadID tid )

Checks all input signals and updates the status as necessary.

Returns: : Returns if the status has changed due to input signals.

Definition at line 999 of file fetch_impl.hh.

Referenced by DefaultFetch< Impl >::checkInterrupt(), and DefaultFetch< Impl >::tick().

◆ checkStall()

template<class Impl >

bool DefaultFetch< Impl >::checkStall ( ThreadID tid ) const

private

Checks if a thread is stalled.

Definition at line 828 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu, DPRINTF, and DefaultFetch< Impl >::stalls.

Referenced by DefaultFetch< Impl >::checkInterrupt(), DefaultFetch< Impl >::checkSignalsAndUpdate(), and DefaultFetch< Impl >::processCacheCompletion().

◆ clearStates()

template<class Impl >

void DefaultFetch< Impl >::clearStates ( ThreadID tid )

Clear all thread-specific states.

Definition at line 334 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu, DefaultFetch< Impl >::Stalls::decode, DefaultFetch< Impl >::delayedCommit, DefaultFetch< Impl >::Stalls::drain, DefaultFetch< Impl >::fetchBufferPC, DefaultFetch< Impl >::fetchBufferValid, DefaultFetch< Impl >::fetchOffset, DefaultFetch< Impl >::fetchQueue, DefaultFetch< Impl >::fetchStatus, DefaultFetch< Impl >::macroop, DefaultFetch< Impl >::memReq, DefaultFetch< Impl >::pc, DefaultFetch< Impl >::Running, and DefaultFetch< Impl >::stalls.

◆ deactivateThread()

template<class Impl >

void DefaultFetch< Impl >::deactivateThread ( ThreadID tid )

For priority-based fetch policies, need to keep update priorityList.

Definition at line 547 of file fetch_impl.hh.

References DefaultFetch< Impl >::priorityList.

◆ doSquash()

template<class Impl >

void DefaultFetch< Impl >::doSquash	(	const TheISA::PCState &	newPC,
		const DynInstPtr	squashInst,
		ThreadID	tid
	)

inlineprivate

◆ drainResume()

template<class Impl >

void DefaultFetch< Impl >::drainResume ( )

Resume after a drain.

Definition at line 433 of file fetch_impl.hh.

References DefaultFetch< Impl >::Stalls::decode, DefaultFetch< Impl >::Stalls::drain, ArmISA::i, DefaultFetch< Impl >::numThreads, and DefaultFetch< Impl >::stalls.

◆ drainSanityCheck()

template<class Impl >

void DefaultFetch< Impl >::drainSanityCheck ( ) const

Perform sanity checks after a drain.

Definition at line 443 of file fetch_impl.hh.

References DefaultFetch< Impl >::branchPred, DefaultFetch< Impl >::cacheBlocked, BPredUnit::drainSanityCheck(), DefaultFetch< Impl >::fetchStatus, ArmISA::i, DefaultFetch< Impl >::Idle, DefaultFetch< Impl >::interruptPending, InvalidThreadID, DefaultFetch< Impl >::isDrained(), DefaultFetch< Impl >::memReq, DefaultFetch< Impl >::numThreads, DefaultFetch< Impl >::retryPkt, DefaultFetch< Impl >::retryTid, and DefaultFetch< Impl >::stalls.

◆ drainStall()

template<class Impl >

void DefaultFetch< Impl >::drainStall ( ThreadID tid )

Stall the fetch stage after reaching a safe drain point.

The CPU uses this method to stop fetching instructions from a thread that has been drained. The drain stall is different from all other stalls in that it is signaled instantly from the commit stage (without the normal communication delay) when it has reached a safe point to drain from.

Definition at line 501 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu, DPRINTF, DefaultFetch< Impl >::Stalls::drain, and DefaultFetch< Impl >::stalls.

◆ fetch()

template<class Impl >

void DefaultFetch< Impl >::fetch ( bool & status_change )

Does the actual fetching of instructions and passing them on to the next stage.

Parameters

status_change fetch() sets this variable if there was a status change (ie switching to IcacheMissStall).

Definition at line 1158 of file fetch_impl.hh.

Referenced by DefaultFetch< Impl >::IcachePort::recvReqRetry(), DefaultFetch< Impl >::IcachePort::recvTimingResp(), and DefaultFetch< Impl >::tick().

◆ fetchBufferAlignPC()

template<class Impl>

Addr DefaultFetch< Impl >::fetchBufferAlignPC ( Addr addr )

inline

Align a PC to the start of a fetch buffer block.

Definition at line 375 of file fetch.hh.

References DefaultFetch< Impl >::fetchBufferMask.

Referenced by DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::fetchCacheLine(), and DefaultFetch< Impl >::pipelineIcacheAccesses().

◆ fetchCacheLine()

template<class Impl >

bool DefaultFetch< Impl >::fetchCacheLine	(	Addr	vaddr,
		ThreadID	tid,
		Addr	pc
	)

private

Fetches the cache line that contains the fetch PC.

Returns any fault that happened. Puts the data into the class variable fetchBuffer, which may not hold the entire fetched cache line.

Parameters

vaddr	The memory address that is being fetched from.
ret_fault	The fault reference that will be set to the result of the icache access.
tid	Thread id.
pc	The actual PC of the current instruction.

Returns: Any fault that occured.

Definition at line 604 of file fetch_impl.hh.

References DefaultFetch< Impl >::cacheBlocked, DefaultFetch< Impl >::checkInterrupt(), DefaultFetch< Impl >::cpu, DefaultFetch< Impl >::delayedCommit, DPRINTF, BaseTLB::Execute, DefaultFetch< Impl >::fetchBufferAlignPC(), DefaultFetch< Impl >::fetchBufferSize, DefaultFetch< Impl >::fetchStatus, Request::INST_FETCH, DefaultFetch< Impl >::ItlbWait, DefaultFetch< Impl >::memReq, NoFault, and DefaultFetch< Impl >::pc.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::pipelineIcacheAccesses().

◆ finishTranslation()

template<class Impl >

void DefaultFetch< Impl >::finishTranslation	(	const Fault &	fault,
		const RequestPtr &	mem_req
	)

private

Definition at line 654 of file fetch_impl.hh.

Referenced by DefaultFetch< Impl >::FetchTranslation::finish(), and DefaultFetch< Impl >::FinishTranslationEvent::process().

◆ getFetchingThread()

template<class Impl >

ThreadID DefaultFetch< Impl >::getFetchingThread ( )

private

Returns the appropriate thread to fetch, given the fetch policy.

Definition at line 1451 of file fetch_impl.hh.

References DefaultFetch< Impl >::activeThreads, DefaultFetch< Impl >::branchCount(), DefaultFetch< Impl >::fetchPolicy, DefaultFetch< Impl >::fetchStatus, DefaultFetch< Impl >::IcacheAccessComplete, DefaultFetch< Impl >::Idle, InvalidThreadID, DefaultFetch< Impl >::iqCount(), DefaultFetch< Impl >::lsqCount(), DefaultFetch< Impl >::numThreads, DefaultFetch< Impl >::roundRobin(), and DefaultFetch< Impl >::Running.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::getInstPort().

◆ getInstPort()

template<class Impl>

MasterPort& DefaultFetch< Impl >::getInstPort ( )

inline

Definition at line 383 of file fetch.hh.

References DefaultFetch< Impl >::branchCount(), DefaultFetch< Impl >::buildInst(), DefaultFetch< Impl >::getFetchingThread(), DefaultFetch< Impl >::icachePort, DefaultFetch< Impl >::iqCount(), DefaultFetch< Impl >::lsqCount(), DefaultFetch< Impl >::pipelineIcacheAccesses(), DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::roundRobin().

◆ iqCount()

template<class Impl >

ThreadID DefaultFetch< Impl >::iqCount ( )

private

Returns the appropriate thread to fetch using the IQ count policy.

Definition at line 1517 of file fetch_impl.hh.

References DefaultFetch< Impl >::activeThreads, DefaultFetch< Impl >::fetchStatus, DefaultFetch< Impl >::fromIEW, DefaultFetch< Impl >::IcacheAccessComplete, DefaultFetch< Impl >::Idle, InvalidThreadID, and DefaultFetch< Impl >::Running.

Referenced by DefaultFetch< Impl >::getFetchingThread(), and DefaultFetch< Impl >::getInstPort().

◆ isDrained()

template<class Impl >

bool DefaultFetch< Impl >::isDrained ( ) const

Has the stage drained?

Definition at line 461 of file fetch_impl.hh.

References DefaultFetch< Impl >::Blocked, DefaultFetch< Impl >::fetchQueue, DefaultFetch< Impl >::fetchStatus, DefaultFetch< Impl >::finishTranslationEvent, ArmISA::i, DefaultFetch< Impl >::Idle, DefaultFetch< Impl >::numThreads, Event::scheduled(), and DefaultFetch< Impl >::stalls.

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

◆ lookupAndUpdateNextPC()

template<class Impl >

bool DefaultFetch< Impl >::lookupAndUpdateNextPC	(	const DynInstPtr &	inst,
		TheISA::PCState &	pc
	)

private

Looks up in the branch predictor to see if the next PC should be either next PC+=MachInst or a branch target.

Parameters

next_PC	Next PC variable passed in by reference. It is expected to be set to the current PC; it will be updated with what the next PC will be.
next_NPC	Used for ISAs which use delay slots.

Returns: Whether or not a branch was predicted as taken.

Definition at line 558 of file fetch_impl.hh.

References AlphaISA::advancePC(), DefaultFetch< Impl >::branchPred, DPRINTF, DefaultFetch< Impl >::fetchedBranches, BPredUnit::predict(), and DefaultFetch< Impl >::predictedBranches.

Referenced by DefaultFetch< Impl >::fetch().

◆ lsqCount()

template<class Impl >

ThreadID DefaultFetch< Impl >::lsqCount ( )

private

Returns the appropriate thread to fetch using the LSQ count policy.

Definition at line 1554 of file fetch_impl.hh.

References DefaultFetch< Impl >::activeThreads, DefaultFetch< Impl >::fetchStatus, DefaultFetch< Impl >::fromIEW, DefaultFetch< Impl >::IcacheAccessComplete, DefaultFetch< Impl >::Idle, InvalidThreadID, and DefaultFetch< Impl >::Running.

Referenced by DefaultFetch< Impl >::getFetchingThread(), and DefaultFetch< Impl >::getInstPort().

◆ name()

template<class Impl >

std::string DefaultFetch< Impl >::name ( ) const

Returns the name of fetch.

Definition at line 154 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu.

Referenced by DefaultFetch< Impl >::regStats().

◆ pipelineIcacheAccesses()

template<class Impl >

void DefaultFetch< Impl >::pipelineIcacheAccesses ( ThreadID tid )

private

Pipeline the next I-cache access to the current one.

Definition at line 1598 of file fetch_impl.hh.

References DPRINTF, DefaultFetch< Impl >::fetchBufferAlignPC(), DefaultFetch< Impl >::fetchBufferPC, DefaultFetch< Impl >::fetchBufferValid, DefaultFetch< Impl >::fetchCacheLine(), DefaultFetch< Impl >::fetchOffset, isRomMicroPC(), DefaultFetch< Impl >::issuePipelinedIfetch, DefaultFetch< Impl >::pc, and BaseCPU::PCMask.

Referenced by DefaultFetch< Impl >::getInstPort(), and DefaultFetch< Impl >::tick().

◆ processCacheCompletion()

template<class Impl >

void DefaultFetch< Impl >::processCacheCompletion ( PacketPtr pkt )

Processes cache completion event.

Definition at line 389 of file fetch_impl.hh.

◆ profileStall()

template<class Impl >

void DefaultFetch< Impl >::profileStall ( ThreadID tid )

private

Profile the reasons of fetch stall.

Definition at line 1628 of file fetch_impl.hh.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::getInstPort().

◆ recvReqRetry()

template<class Impl >

void DefaultFetch< Impl >::recvReqRetry ( )

Handles retrying the fetch access.

Definition at line 1420 of file fetch_impl.hh.

References DefaultFetch< Impl >::cacheBlocked, DefaultFetch< Impl >::fetchStatus, DefaultFetch< Impl >::icachePort, DefaultFetch< Impl >::IcacheWaitResponse, DefaultFetch< Impl >::IcacheWaitRetry, InvalidThreadID, ProbePointArg< Arg >::notify(), DefaultFetch< Impl >::ppFetchRequestSent, Packet::req, DefaultFetch< Impl >::retryPkt, DefaultFetch< Impl >::retryTid, and MasterPort::sendTimingReq().

◆ regProbePoints()

template<class Impl >

void DefaultFetch< Impl >::regProbePoints ( )

Registers probes.

Definition at line 161 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu, DefaultFetch< Impl >::ppFetch, and DefaultFetch< Impl >::ppFetchRequestSent.

◆ regStats()

template<class Impl >

void DefaultFetch< Impl >::regStats ( )

Registers statistics.

Definition at line 171 of file fetch_impl.hh.

◆ resetStage()

template<class Impl >

void DefaultFetch< Impl >::resetStage ( )

private

Reset this pipeline stage.

Definition at line 354 of file fetch_impl.hh.

Referenced by DefaultFetch< Impl >::startupStage(), and DefaultFetch< Impl >::takeOverFrom().

◆ roundRobin()

template<class Impl >

ThreadID DefaultFetch< Impl >::roundRobin ( )

private

Returns the appropriate thread to fetch using a round robin policy.

Definition at line 1487 of file fetch_impl.hh.

References DefaultFetch< Impl >::fetchStatus, DefaultFetch< Impl >::IcacheAccessComplete, DefaultFetch< Impl >::Idle, InvalidThreadID, DefaultFetch< Impl >::numThreads, DefaultFetch< Impl >::priorityList, and DefaultFetch< Impl >::Running.

Referenced by DefaultFetch< Impl >::getFetchingThread(), and DefaultFetch< Impl >::getInstPort().

◆ setActiveThreads()

template<class Impl >

void DefaultFetch< Impl >::setActiveThreads ( std::list< ThreadID > * at_ptr )

Sets pointer to list of active threads.

Definition at line 307 of file fetch_impl.hh.

References DefaultFetch< Impl >::activeThreads.

◆ setFetchQueue()

template<class Impl >

void DefaultFetch< Impl >::setFetchQueue ( TimeBuffer< FetchStruct > * fq_ptr )

Sets pointer to time buffer used to communicate to the next stage.

Definition at line 314 of file fetch_impl.hh.

References TimeBuffer< T >::getWire(), and DefaultFetch< Impl >::toDecode.

◆ setTimeBuffer()

template<class Impl >

void DefaultFetch< Impl >::setTimeBuffer ( TimeBuffer< TimeStruct > * time_buffer )

Sets the main backwards communication time buffer pointer.

Definition at line 294 of file fetch_impl.hh.

References DefaultFetch< Impl >::commitToFetchDelay, DefaultFetch< Impl >::decodeToFetchDelay, DefaultFetch< Impl >::fromCommit, DefaultFetch< Impl >::fromDecode, DefaultFetch< Impl >::fromIEW, DefaultFetch< Impl >::fromRename, TimeBuffer< T >::getWire(), DefaultFetch< Impl >::iewToFetchDelay, DefaultFetch< Impl >::renameToFetchDelay, and DefaultFetch< Impl >::timeBuffer.

◆ squash()

template<class Impl >

void DefaultFetch< Impl >::squash	(	const TheISA::PCState &	newPC,
		const InstSeqNum	seq_num,
		DynInstPtr	squashInst,
		ThreadID	tid
	)

Squashes a specific thread and resets the PC.

Also tells the CPU to remove any instructions that are not in the ROB. The source of this squash should be the commit stage.

Definition at line 883 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu, DefaultFetch< Impl >::doSquash(), and DPRINTF.

Referenced by DefaultFetch< Impl >::checkInterrupt(), and DefaultFetch< Impl >::checkSignalsAndUpdate().

◆ squashFromDecode()

template<class Impl >

void DefaultFetch< Impl >::squashFromDecode	(	const TheISA::PCState &	newPC,
		const DynInstPtr	squashInst,
		const InstSeqNum	seq_num,
		ThreadID	tid
	)

private

Squashes a specific thread and resets the PC.

Also tells the CPU to remove any instructions between fetch and decode that should be sqaushed.

Definition at line 813 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu, DefaultFetch< Impl >::doSquash(), and DPRINTF.

Referenced by DefaultFetch< Impl >::checkInterrupt(), and DefaultFetch< Impl >::checkSignalsAndUpdate().

◆ startupStage()

template<class Impl >

void DefaultFetch< Impl >::startupStage ( )

Initialize stage.

Definition at line 322 of file fetch_impl.hh.

References DefaultFetch< Impl >::priorityList, DefaultFetch< Impl >::resetStage(), and DefaultFetch< Impl >::switchToActive().

◆ switchToActive()

template<class Impl >

void DefaultFetch< Impl >::switchToActive ( )

inlineprivate

Changes the status of this stage to active, and indicates this to the CPU.

Definition at line 521 of file fetch_impl.hh.

References DefaultFetch< Impl >::_status, DefaultFetch< Impl >::Active, DefaultFetch< Impl >::cpu, DPRINTF, and DefaultFetch< Impl >::Inactive.

Referenced by DefaultFetch< Impl >::processCacheCompletion(), and DefaultFetch< Impl >::startupStage().

◆ switchToInactive()

template<class Impl >

void DefaultFetch< Impl >::switchToInactive ( )

inlineprivate

Changes the status of this stage to inactive, and indicates this to the CPU.

Definition at line 534 of file fetch_impl.hh.

References DefaultFetch< Impl >::_status, DefaultFetch< Impl >::Active, DefaultFetch< Impl >::cpu, DPRINTF, and DefaultFetch< Impl >::Inactive.

◆ takeOverFrom()

template<class Impl >

void DefaultFetch< Impl >::takeOverFrom ( )

Takes over from another CPU's thread.

Definition at line 492 of file fetch_impl.hh.

References DefaultFetch< Impl >::cpu, and DefaultFetch< Impl >::resetStage().

◆ tick()

template<class Impl >

void DefaultFetch< Impl >::tick ( )

Ticks the fetch stage, processing all inputs signals and fetching as many instructions as possible.

Definition at line 897 of file fetch_impl.hh.

Referenced by DefaultFetch< Impl >::checkInterrupt().

◆ updateFetchStatus()

template<class Impl >

DefaultFetch< Impl >::FetchStatus DefaultFetch< Impl >::updateFetchStatus ( )

private

Updates overall fetch stage status; to be called at the end of each cycle.

Definition at line 843 of file fetch_impl.hh.

References DefaultFetch< Impl >::_status, DefaultFetch< Impl >::Active, DefaultFetch< Impl >::activeThreads, DefaultFetch< Impl >::cpu, DPRINTF, DefaultFetch< Impl >::fetchStatus, DefaultFetch< Impl >::IcacheAccessComplete, DefaultFetch< Impl >::Inactive, DefaultFetch< Impl >::Running, and DefaultFetch< Impl >::Squashing.

Referenced by DefaultFetch< Impl >::checkInterrupt(), DefaultFetch< Impl >::finishTranslation(), and DefaultFetch< Impl >::tick().

◆ wakeFromQuiesce()

template<class Impl >

void DefaultFetch< Impl >::wakeFromQuiesce ( )

Tells fetch to wake up from a quiesce instruction.

Definition at line 511 of file fetch_impl.hh.

References DPRINTF, DefaultFetch< Impl >::fetchStatus, and DefaultFetch< Impl >::Running.

Member Data Documentation

◆ _status

template<class Impl>

FetchStatus DefaultFetch< Impl >::_status

private

Fetch status.

Definition at line 205 of file fetch.hh.

Referenced by DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::resetStage(), DefaultFetch< Impl >::switchToActive(), DefaultFetch< Impl >::switchToInactive(), DefaultFetch< Impl >::tick(), and DefaultFetch< Impl >::updateFetchStatus().

◆ activeThreads

template<class Impl>

std::list<ThreadID>* DefaultFetch< Impl >::activeThreads

private

List of Active Threads.

Definition at line 527 of file fetch.hh.

Referenced by DefaultFetch< Impl >::getFetchingThread(), DefaultFetch< Impl >::iqCount(), DefaultFetch< Impl >::lsqCount(), DefaultFetch< Impl >::profileStall(), DefaultFetch< Impl >::setActiveThreads(), DefaultFetch< Impl >::tick(), and DefaultFetch< Impl >::updateFetchStatus().

◆ branchPred

template<class Impl>

BPredUnit* DefaultFetch< Impl >::branchPred

private

BPredUnit.

Definition at line 436 of file fetch.hh.

Referenced by DefaultFetch< Impl >::checkSignalsAndUpdate(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::drainSanityCheck(), and DefaultFetch< Impl >::lookupAndUpdateNextPC().

◆ branchRate

template<class Impl>

Stats::Formula DefaultFetch< Impl >::branchRate

private

Number of branch fetches per cycle.

Definition at line 600 of file fetch.hh.

Referenced by DefaultFetch< Impl >::regStats().

◆ cacheBlkSize

template<class Impl>

unsigned int DefaultFetch< Impl >::cacheBlkSize

private

Cache block size.

Definition at line 495 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch().

◆ cacheBlocked

template<class Impl>

bool DefaultFetch< Impl >::cacheBlocked

private

Is the cache blocked? If so no threads can access it.

Definition at line 486 of file fetch.hh.

Referenced by DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::drainSanityCheck(), DefaultFetch< Impl >::fetchCacheLine(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::recvReqRetry(), and DefaultFetch< Impl >::resetStage().

◆ commitToFetchDelay

template<class Impl>

Cycles DefaultFetch< Impl >::commitToFetchDelay

private

Commit to fetch delay.

Definition at line 477 of file fetch.hh.

Referenced by DefaultFetch< Impl >::setTimeBuffer().

◆ cpu

template<class Impl>

O3CPU* DefaultFetch< Impl >::cpu

private

◆ decoder

template<class Impl>

TheISA::Decoder* DefaultFetch< Impl >::decoder[Impl::MaxThreads]

The decoder.

Definition at line 381 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::doSquash(), and DefaultFetch< Impl >::fetch().

◆ decodeToFetchDelay

template<class Impl>

Cycles DefaultFetch< Impl >::decodeToFetchDelay

private

Decode to fetch delay.

Definition at line 468 of file fetch.hh.

Referenced by DefaultFetch< Impl >::setTimeBuffer().

◆ decodeWidth

template<class Impl>

unsigned DefaultFetch< Impl >::decodeWidth

private

The width of decode in instructions.

Definition at line 483 of file fetch.hh.

Referenced by DefaultFetch< Impl >::tick().

◆ delayedCommit

template<class Impl>

bool DefaultFetch< Impl >::delayedCommit[Impl::MaxThreads]

private

Can the fetch stage redirect from an interrupt on this instruction?

Definition at line 445 of file fetch.hh.

Referenced by DefaultFetch< Impl >::buildInst(), DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::fetchCacheLine(), and DefaultFetch< Impl >::resetStage().

◆ fetchBlockedCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchBlockedCycles

private

Total number of cycles spent blocked.

Definition at line 572 of file fetch.hh.

Referenced by DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ fetchBuffer

template<class Impl>

uint8_t* DefaultFetch< Impl >::fetchBuffer[Impl::MaxThreads]

private

The fetch data that is being fetched and buffered.

Definition at line 506 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::processCacheCompletion().

◆ fetchBufferMask

template<class Impl>

Addr DefaultFetch< Impl >::fetchBufferMask

private

Mask to align a fetch address to a fetch buffer boundary.

Definition at line 503 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetchBufferAlignPC().

◆ fetchBufferPC

template<class Impl>

Addr DefaultFetch< Impl >::fetchBufferPC[Impl::MaxThreads]

private

The PC of the first instruction loaded into the fetch buffer.

Definition at line 509 of file fetch.hh.

Referenced by DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::pipelineIcacheAccesses(), and DefaultFetch< Impl >::resetStage().

◆ fetchBufferSize

template<class Impl>

unsigned DefaultFetch< Impl >::fetchBufferSize

private

The size of the fetch buffer in bytes.

The fetch buffer itself may be smaller than a cache line.

Definition at line 500 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::fetchCacheLine(), DefaultFetch< Impl >::finishTranslation(), and DefaultFetch< Impl >::processCacheCompletion().

◆ fetchBufferValid

template<class Impl>

bool DefaultFetch< Impl >::fetchBufferValid[Impl::MaxThreads]

private

Whether or not the fetch buffer data is valid.

Definition at line 518 of file fetch.hh.

Referenced by DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::pipelineIcacheAccesses(), DefaultFetch< Impl >::processCacheCompletion(), and DefaultFetch< Impl >::resetStage().

◆ fetchCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchCycles

private

Stat for total number of cycles spent fetching.

Definition at line 562 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::regStats().

◆ fetchedBranches

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchedBranches

private

Total number of fetched branches.

Definition at line 558 of file fetch.hh.

Referenced by DefaultFetch< Impl >::lookupAndUpdateNextPC(), and DefaultFetch< Impl >::regStats().

◆ fetchedCacheLines

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchedCacheLines

private

Stat for total number of fetched cache lines.

Definition at line 586 of file fetch.hh.

Referenced by DefaultFetch< Impl >::finishTranslation(), and DefaultFetch< Impl >::regStats().

◆ fetchedInsts

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchedInsts

private

Stat for total number of fetched instructions.

Definition at line 556 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::regStats().

◆ fetchIcacheSquashes

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchIcacheSquashes

private

Total number of outstanding icache accesses that were dropped due to a squash.

Definition at line 590 of file fetch.hh.

Referenced by DefaultFetch< Impl >::processCacheCompletion(), and DefaultFetch< Impl >::regStats().

◆ fetchIcacheWaitRetryStallCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchIcacheWaitRetryStallCycles

private

Total number of stall cycles caused by I-cache wait retrys.

Definition at line 584 of file fetch.hh.

Referenced by DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ fetchIdleCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchIdleCycles

private

Stat for total number of cycles spent blocked due to other stages in the pipeline.

Definition at line 570 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::regStats().

◆ fetchMiscStallCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchMiscStallCycles

private

Total number of cycles spent in any other state.

Definition at line 574 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::regStats().

◆ fetchNisnDist

template<class Impl>

Stats::Distribution DefaultFetch< Impl >::fetchNisnDist

private

Distribution of number of instructions fetched each cycle.

Definition at line 596 of file fetch.hh.

Referenced by DefaultFetch< Impl >::regStats(), and DefaultFetch< Impl >::tick().

◆ fetchNoActiveThreadStallCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchNoActiveThreadStallCycles

private

Total number of stall cycles caused by no active threads to run.

Definition at line 578 of file fetch.hh.

Referenced by DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ fetchOffset

template<class Impl>

Addr DefaultFetch< Impl >::fetchOffset[Impl::MaxThreads]

private

Definition at line 440 of file fetch.hh.

Referenced by DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::pipelineIcacheAccesses(), and DefaultFetch< Impl >::resetStage().

◆ fetchPendingDrainCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchPendingDrainCycles

private

Total number of cycles spent in waiting for drains.

Definition at line 576 of file fetch.hh.

Referenced by DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ fetchPendingQuiesceStallCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchPendingQuiesceStallCycles

private

Total number of stall cycles caused by pending quiesce instructions.

Definition at line 582 of file fetch.hh.

Referenced by DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ fetchPendingTrapStallCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchPendingTrapStallCycles

private

Total number of stall cycles caused by pending traps.

Definition at line 580 of file fetch.hh.

Referenced by DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ fetchPolicy

template<class Impl>

FetchPolicy DefaultFetch< Impl >::fetchPolicy

private

Fetch policy.

Definition at line 211 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch(), and DefaultFetch< Impl >::getFetchingThread().

◆ fetchQueue

template<class Impl>

std::deque<DynInstPtr> DefaultFetch< Impl >::fetchQueue[Impl::MaxThreads]

private

Queue of fetched instructions.

Per-thread to prevent HoL blocking.

Definition at line 515 of file fetch.hh.

Referenced by DefaultFetch< Impl >::buildInst(), DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::isDrained(), DefaultFetch< Impl >::resetStage(), and DefaultFetch< Impl >::tick().

◆ fetchQueueSize

template<class Impl>

unsigned DefaultFetch< Impl >::fetchQueueSize

private

The size of the fetch queue in micro-ops.

Definition at line 512 of file fetch.hh.

Referenced by DefaultFetch< Impl >::buildInst(), DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::finishTranslation().

◆ fetchRate

template<class Impl>

Stats::Formula DefaultFetch< Impl >::fetchRate

private

Number of instruction fetched per cycle.

Definition at line 602 of file fetch.hh.

Referenced by DefaultFetch< Impl >::regStats().

◆ fetchSquashCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchSquashCycles

private

Stat for total number of cycles spent squashing.

Definition at line 564 of file fetch.hh.

Referenced by DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ fetchStatus

template<class Impl>

ThreadStatus DefaultFetch< Impl >::fetchStatus[Impl::MaxThreads]

private

◆ fetchTlbCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchTlbCycles

private

Stat for total number of cycles spent waiting for translation.

Definition at line 566 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ fetchTlbSquashes

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::fetchTlbSquashes

private

Total number of outstanding tlb accesses that were dropped due to a squash.

Definition at line 594 of file fetch.hh.

Referenced by DefaultFetch< Impl >::finishTranslation(), and DefaultFetch< Impl >::regStats().

◆ fetchWidth

template<class Impl>

unsigned DefaultFetch< Impl >::fetchWidth

private

The width of fetch in instructions.

Definition at line 480 of file fetch.hh.

Referenced by DefaultFetch< Impl >::buildInst(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::FinishTranslationEvent::process(), and DefaultFetch< Impl >::regStats().

◆ finishTranslationEvent

template<class Impl>

FinishTranslationEvent DefaultFetch< Impl >::finishTranslationEvent

private

Event used to delay fault generation of translation faults.

Definition at line 550 of file fetch.hh.

Referenced by DefaultFetch< Impl >::finishTranslation(), and DefaultFetch< Impl >::isDrained().

◆ fromCommit

template<class Impl>

TimeBuffer<TimeStruct>::wire DefaultFetch< Impl >::fromCommit

private

Wire to get commit's information from backwards time buffer.

Definition at line 429 of file fetch.hh.

Referenced by DefaultFetch< Impl >::checkSignalsAndUpdate(), DefaultFetch< Impl >::setTimeBuffer(), and DefaultFetch< Impl >::tick().

◆ fromDecode

template<class Impl>

TimeBuffer<TimeStruct>::wire DefaultFetch< Impl >::fromDecode

private

Wire to get decode's information from backwards time buffer.

Definition at line 420 of file fetch.hh.

Referenced by DefaultFetch< Impl >::checkSignalsAndUpdate(), and DefaultFetch< Impl >::setTimeBuffer().

◆ fromIEW

template<class Impl>

TimeBuffer<TimeStruct>::wire DefaultFetch< Impl >::fromIEW

private

Wire to get iew's information from backwards time buffer.

Definition at line 426 of file fetch.hh.

Referenced by DefaultFetch< Impl >::iqCount(), DefaultFetch< Impl >::lsqCount(), and DefaultFetch< Impl >::setTimeBuffer().

◆ fromRename

template<class Impl>

TimeBuffer<TimeStruct>::wire DefaultFetch< Impl >::fromRename

private

Wire to get rename's information from backwards time buffer.

Definition at line 423 of file fetch.hh.

Referenced by DefaultFetch< Impl >::setTimeBuffer().

◆ icachePort

template<class Impl>

IcachePort DefaultFetch< Impl >::icachePort

private

Instruction port.

Note that it has to appear after the fetch stage.

Definition at line 544 of file fetch.hh.

Referenced by DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::getInstPort(), and DefaultFetch< Impl >::recvReqRetry().

◆ icacheStallCycles

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::icacheStallCycles

private

Stat for total number of cycles stalled due to an icache miss.

Definition at line 554 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::profileStall(), and DefaultFetch< Impl >::regStats().

◆ idleRate

template<class Impl>

Stats::Formula DefaultFetch< Impl >::idleRate

private

Rate of how often fetch was idle.

Definition at line 598 of file fetch.hh.

Referenced by DefaultFetch< Impl >::regStats().

◆ iewToFetchDelay

template<class Impl>

Cycles DefaultFetch< Impl >::iewToFetchDelay

private

IEW to fetch delay.

Definition at line 474 of file fetch.hh.

Referenced by DefaultFetch< Impl >::setTimeBuffer().

◆ instSize

template<class Impl>

int DefaultFetch< Impl >::instSize

private

Size of instructions.

Definition at line 521 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch(), and DefaultFetch< Impl >::fetch().

◆ interruptPending

template<class Impl>

bool DefaultFetch< Impl >::interruptPending

private

Checks if there is an interrupt pending.

If there is, fetch must stop once it is not fetching PAL instructions.

Definition at line 541 of file fetch.hh.

Referenced by DefaultFetch< Impl >::checkInterrupt(), DefaultFetch< Impl >::drainSanityCheck(), DefaultFetch< Impl >::resetStage(), and DefaultFetch< Impl >::tick().

◆ issuePipelinedIfetch

template<class Impl>

bool DefaultFetch< Impl >::issuePipelinedIfetch[Impl::MaxThreads]

private

Set to true if a pipelined I-cache request should be issued.

Definition at line 547 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::pipelineIcacheAccesses(), and DefaultFetch< Impl >::tick().

◆ lastIcacheStall

template<class Impl>

Counter DefaultFetch< Impl >::lastIcacheStall[Impl::MaxThreads]

private

Icache stall statistics.

Definition at line 524 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch(), and DefaultFetch< Impl >::finishTranslation().

◆ macroop

template<class Impl>

StaticInstPtr DefaultFetch< Impl >::macroop[Impl::MaxThreads]

private

Definition at line 442 of file fetch.hh.

Referenced by DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::resetStage().

◆ memReq

template<class Impl>

RequestPtr DefaultFetch< Impl >::memReq[Impl::MaxThreads]

private

Memory request used to access cache.

Definition at line 448 of file fetch.hh.

Referenced by DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::drainSanityCheck(), DefaultFetch< Impl >::fetchCacheLine(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::processCacheCompletion(), and DefaultFetch< Impl >::resetStage().

◆ numFetchingThreads

template<class Impl>

ThreadID DefaultFetch< Impl >::numFetchingThreads

private

Number of threads that are actively fetching.

Definition at line 533 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::tick().

◆ numInst

template<class Impl>

int DefaultFetch< Impl >::numInst

private

Tracks how many instructions has been fetched this cycle.

Definition at line 456 of file fetch.hh.

Referenced by DefaultFetch< Impl >::buildInst(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::FinishTranslationEvent::process(), DefaultFetch< Impl >::resetStage(), and DefaultFetch< Impl >::tick().

◆ numThreads

template<class Impl>

ThreadID DefaultFetch< Impl >::numThreads

private

Number of threads.

Definition at line 530 of file fetch.hh.

Referenced by DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::drainResume(), DefaultFetch< Impl >::drainSanityCheck(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::getFetchingThread(), DefaultFetch< Impl >::isDrained(), DefaultFetch< Impl >::resetStage(), DefaultFetch< Impl >::roundRobin(), and DefaultFetch< Impl >::tick().

◆ pc

template<class Impl>

TheISA::PCState DefaultFetch< Impl >::pc[Impl::MaxThreads]

private

Definition at line 438 of file fetch.hh.

Referenced by DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::fetchCacheLine(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::pipelineIcacheAccesses(), and DefaultFetch< Impl >::resetStage().

◆ ppFetch

template<class Impl>

ProbePointArg<DynInstPtr>* DefaultFetch< Impl >::ppFetch

private

Probe points.

Definition at line 217 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::regProbePoints().

◆ ppFetchRequestSent

template<class Impl>

ProbePointArg<RequestPtr>* DefaultFetch< Impl >::ppFetchRequestSent

private

To probe when a fetch request is successfully sent.

Definition at line 219 of file fetch.hh.

Referenced by DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::recvReqRetry(), and DefaultFetch< Impl >::regProbePoints().

◆ predictedBranches

template<class Impl>

Stats::Scalar DefaultFetch< Impl >::predictedBranches

private

Stat for total number of predicted branches.

Definition at line 560 of file fetch.hh.

Referenced by DefaultFetch< Impl >::lookupAndUpdateNextPC(), and DefaultFetch< Impl >::regStats().

◆ priorityList

template<class Impl>

std::list<ThreadID> DefaultFetch< Impl >::priorityList

private

List that has the threads organized by priority.

Definition at line 214 of file fetch.hh.

Referenced by DefaultFetch< Impl >::deactivateThread(), DefaultFetch< Impl >::resetStage(), DefaultFetch< Impl >::roundRobin(), and DefaultFetch< Impl >::startupStage().

◆ renameToFetchDelay

template<class Impl>

Cycles DefaultFetch< Impl >::renameToFetchDelay

private

Rename to fetch delay.

Definition at line 471 of file fetch.hh.

Referenced by DefaultFetch< Impl >::setTimeBuffer().

◆ retryPkt

template<class Impl>

PacketPtr DefaultFetch< Impl >::retryPkt

private

The packet that is waiting to be retried.

Definition at line 489 of file fetch.hh.

Referenced by DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::drainSanityCheck(), DefaultFetch< Impl >::finishTranslation(), and DefaultFetch< Impl >::recvReqRetry().

◆ retryTid

template<class Impl>

ThreadID DefaultFetch< Impl >::retryTid

private

The thread that is waiting on the cache to tell fetch to retry.

Definition at line 492 of file fetch.hh.

Referenced by DefaultFetch< Impl >::doSquash(), DefaultFetch< Impl >::drainSanityCheck(), DefaultFetch< Impl >::finishTranslation(), and DefaultFetch< Impl >::recvReqRetry().

◆ stalls

template<class Impl>

Stalls DefaultFetch< Impl >::stalls[Impl::MaxThreads]

private

Tracks which stages are telling fetch to stall.

Definition at line 465 of file fetch.hh.

Referenced by DefaultFetch< Impl >::checkSignalsAndUpdate(), DefaultFetch< Impl >::checkStall(), DefaultFetch< Impl >::clearStates(), DefaultFetch< Impl >::DefaultFetch(), DefaultFetch< Impl >::drainResume(), DefaultFetch< Impl >::drainSanityCheck(), DefaultFetch< Impl >::drainStall(), DefaultFetch< Impl >::isDrained(), DefaultFetch< Impl >::profileStall(), DefaultFetch< Impl >::resetStage(), and DefaultFetch< Impl >::tick().

◆ threadFetched

template<class Impl>

ThreadID DefaultFetch< Impl >::threadFetched

private

Thread ID being fetched.

Definition at line 536 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), and DefaultFetch< Impl >::tick().

◆ timeBuffer

template<class Impl>

TimeBuffer<TimeStruct>* DefaultFetch< Impl >::timeBuffer

private

Time buffer interface.

Definition at line 417 of file fetch.hh.

Referenced by DefaultFetch< Impl >::setTimeBuffer().

◆ toDecode

template<class Impl>

TimeBuffer<FetchStruct>::wire DefaultFetch< Impl >::toDecode

private

Wire used to write any information heading to decode.

Definition at line 433 of file fetch.hh.

Referenced by DefaultFetch< Impl >::setFetchQueue(), and DefaultFetch< Impl >::tick().

◆ wroteToTimeBuffer

template<class Impl>

bool DefaultFetch< Impl >::wroteToTimeBuffer

private

Variable that tracks if fetch has written to the time buffer this cycle.

Used to tell CPU if there is activity this cycle.

Definition at line 453 of file fetch.hh.

Referenced by DefaultFetch< Impl >::fetch(), DefaultFetch< Impl >::finishTranslation(), DefaultFetch< Impl >::resetStage(), and DefaultFetch< Impl >::tick().

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

cpu/o3/fetch.hh
cpu/o3/fetch_impl.hh

Classes

Public Types

Public Member Functions

Public Attributes

Private Member Functions

Private Attributes

Detailed Description

template<class Impl> class DefaultFetch< Impl >

Member Typedef Documentation

◆ CPUPol

◆ DynInst

◆ DynInstPtr

◆ FetchStruct

◆ MachInst

◆ O3CPU

◆ TimeStruct

Member Enumeration Documentation

◆ FetchStatus

◆ ThreadStatus

Constructor & Destructor Documentation

◆ DefaultFetch()

Member Function Documentation

◆ branchCount()

◆ buildInst()

◆ checkInterrupt()

◆ checkSignalsAndUpdate()

◆ checkStall()

◆ clearStates()

◆ deactivateThread()

◆ doSquash()

◆ drainResume()

◆ drainSanityCheck()

◆ drainStall()

◆ fetch()

◆ fetchBufferAlignPC()

◆ fetchCacheLine()

◆ finishTranslation()

◆ getFetchingThread()

◆ getInstPort()

◆ iqCount()

◆ isDrained()

◆ lookupAndUpdateNextPC()

◆ lsqCount()

◆ name()

◆ pipelineIcacheAccesses()

◆ processCacheCompletion()

◆ profileStall()

◆ recvReqRetry()

◆ regProbePoints()

◆ regStats()

◆ resetStage()

◆ roundRobin()

◆ setActiveThreads()

◆ setFetchQueue()

◆ setTimeBuffer()

◆ squash()

◆ squashFromDecode()

◆ startupStage()

◆ switchToActive()

◆ switchToInactive()

◆ takeOverFrom()

◆ tick()

◆ updateFetchStatus()

◆ wakeFromQuiesce()

Member Data Documentation

◆ _status

◆ activeThreads

◆ branchPred

◆ branchRate

◆ cacheBlkSize

◆ cacheBlocked

◆ commitToFetchDelay

◆ cpu

◆ decoder

◆ decodeToFetchDelay

◆ decodeWidth

◆ delayedCommit

◆ fetchBlockedCycles

◆ fetchBuffer

◆ fetchBufferMask

template<class Impl>
class DefaultFetch< Impl >