gem5  v20.1.0.0
Public Types | Public Member Functions | Protected Attributes | List of all members
BaseIndexingPolicy Class Referenceabstract

A common base class for indexing table locations. More...

#include <base.hh>

Inheritance diagram for BaseIndexingPolicy:
SimObject EventManager Serializable Drainable Stats::Group SetAssociative SkewedAssociative Prefetcher::StridePrefetcherHashedSetAssociative

Public Types

typedef BaseIndexingPolicyParams Params
 Convenience typedef. More...
 
- Public Types inherited from SimObject
typedef SimObjectParams Params
 

Public Member Functions

 BaseIndexingPolicy (const Params *p)
 Construct and initialize this policy. More...
 
 ~BaseIndexingPolicy ()
 Destructor. More...
 
void setEntry (ReplaceableEntry *entry, const uint64_t index)
 Associate a pointer to an entry to its physical counterpart. More...
 
ReplaceableEntrygetEntry (const uint32_t set, const uint32_t way) const
 Get an entry based on its set and way. More...
 
virtual Addr extractTag (const Addr addr) const
 Generate the tag from the given address. More...
 
virtual std::vector< ReplaceableEntry * > getPossibleEntries (const Addr addr) const =0
 Find all possible entries for insertion and replacement of an address. More...
 
virtual Addr regenerateAddr (const Addr tag, const ReplaceableEntry *entry) const =0
 Regenerate an entry's address from its tag and assigned indexing bits. More...
 
- Public Member Functions inherited from SimObject
const Paramsparams () const
 
 SimObject (const Params *_params)
 
virtual ~SimObject ()
 
virtual const std::string name () const
 
virtual void init ()
 init() is called after all C++ SimObjects have been created and all ports are connected. More...
 
virtual void loadState (CheckpointIn &cp)
 loadState() is called on each SimObject when restoring from a checkpoint. More...
 
virtual void initState ()
 initState() is called on each SimObject when not restoring from a checkpoint. More...
 
virtual void regProbePoints ()
 Register probe points for this object. More...
 
virtual void regProbeListeners ()
 Register probe listeners for this object. More...
 
ProbeManagergetProbeManager ()
 Get the probe manager for this object. More...
 
virtual PortgetPort (const std::string &if_name, PortID idx=InvalidPortID)
 Get a port with a given name and index. More...
 
virtual void startup ()
 startup() is the final initialization call before simulation. More...
 
DrainState drain () override
 Provide a default implementation of the drain interface for objects that don't need draining. More...
 
virtual void memWriteback ()
 Write back dirty buffers to memory using functional writes. More...
 
virtual void memInvalidate ()
 Invalidate the contents of memory buffers. More...
 
void serialize (CheckpointOut &cp) const override
 Serialize an object. More...
 
void unserialize (CheckpointIn &cp) override
 Unserialize an object. More...
 
- Public Member Functions inherited from EventManager
EventQueueeventQueue () const
 
void schedule (Event &event, Tick when)
 
void deschedule (Event &event)
 
void reschedule (Event &event, Tick when, bool always=false)
 
void schedule (Event *event, Tick when)
 
void deschedule (Event *event)
 
void reschedule (Event *event, Tick when, bool always=false)
 
void wakeupEventQueue (Tick when=(Tick) -1)
 This function is not needed by the usual gem5 event loop but may be necessary in derived EventQueues which host gem5 on other schedulers. More...
 
void setCurTick (Tick newVal)
 
 EventManager (EventManager &em)
 Event manger manages events in the event queue. More...
 
 EventManager (EventManager *em)
 
 EventManager (EventQueue *eq)
 
- Public Member Functions inherited from Serializable
 Serializable ()
 
virtual ~Serializable ()
 
void serializeSection (CheckpointOut &cp, const char *name) const
 Serialize an object into a new section. More...
 
void serializeSection (CheckpointOut &cp, const std::string &name) const
 
void unserializeSection (CheckpointIn &cp, const char *name)
 Unserialize an a child object. More...
 
void unserializeSection (CheckpointIn &cp, const std::string &name)
 
- Public Member Functions inherited from Drainable
DrainState drainState () const
 Return the current drain state of an object. More...
 
virtual void notifyFork ()
 Notify a child process of a fork. More...
 
- Public Member Functions inherited from Stats::Group
 Group (Group *parent, const char *name=nullptr)
 Construct a new statistics group. More...
 
virtual ~Group ()
 
virtual void regStats ()
 Callback to set stat parameters. More...
 
virtual void resetStats ()
 Callback to reset stats. More...
 
virtual void preDumpStats ()
 Callback before stats are dumped. More...
 
void addStat (Stats::Info *info)
 Register a stat with this group. More...
 
const std::map< std::string, Group * > & getStatGroups () const
 Get all child groups associated with this object. More...
 
const std::vector< Info * > & getStats () const
 Get all stats associated with this object. More...
 
void addStatGroup (const char *name, Group *block)
 Add a stat block as a child of this block. More...
 
const InforesolveStat (std::string name) const
 Resolve a stat by its name within this group. More...
 
 Group ()=delete
 
 Group (const Group &)=delete
 
Groupoperator= (const Group &)=delete
 

Protected Attributes

const unsigned assoc
 The associativity. More...
 
const uint32_t numSets
 The number of sets in the cache. More...
 
const int setShift
 The amount to shift the address to get the set. More...
 
const unsigned setMask
 Mask out all bits that aren't part of the set index. More...
 
std::vector< std::vector< ReplaceableEntry * > > sets
 The cache sets. More...
 
const int tagShift
 The amount to shift the address to get the tag. More...
 
- Protected Attributes inherited from SimObject
const SimObjectParams * _params
 Cached copy of the object parameters. More...
 
- Protected Attributes inherited from EventManager
EventQueueeventq
 A pointer to this object's event queue. More...
 

Additional Inherited Members

- Static Public Member Functions inherited from SimObject
static void serializeAll (CheckpointOut &cp)
 Serialize all SimObjects in the system. More...
 
static SimObjectfind (const char *name)
 Find the SimObject with the given name and return a pointer to it. More...
 
- Static Public Member Functions inherited from Serializable
static const std::string & currentSection ()
 Gets the fully-qualified name of the active section. More...
 
static void serializeAll (const std::string &cpt_dir)
 Serializes all the SimObjects. More...
 
static void unserializeGlobals (CheckpointIn &cp)
 
- Protected Member Functions inherited from Drainable
 Drainable ()
 
virtual ~Drainable ()
 
virtual void drainResume ()
 Resume execution after a successful drain. More...
 
void signalDrainDone () const
 Signal that an object is drained. More...
 

Detailed Description

A common base class for indexing table locations.

Classes that inherit from it determine hash functions that should be applied based on the set and way. These functions are then applied to re-map the original values.

See also
gem5 Memory System

Definition at line 63 of file base.hh.

Member Typedef Documentation

◆ Params

typedef BaseIndexingPolicyParams BaseIndexingPolicy::Params

Convenience typedef.

Definition at line 100 of file base.hh.

Constructor & Destructor Documentation

◆ BaseIndexingPolicy()

BaseIndexingPolicy::BaseIndexingPolicy ( const Params p)

Construct and initialize this policy.

Definition at line 55 of file base.cc.

References assoc, fatal_if, ArmISA::i, isPowerOf2(), numSets, and sets.

◆ ~BaseIndexingPolicy()

BaseIndexingPolicy::~BaseIndexingPolicy ( )
inline

Destructor.

Definition at line 110 of file base.hh.

Member Function Documentation

◆ extractTag()

Addr BaseIndexingPolicy::extractTag ( const Addr  addr) const
virtual

Generate the tag from the given address.

Parameters
addrThe address to get the tag from.
Returns
The tag of the address.

Reimplemented in Prefetcher::StridePrefetcherHashedSetAssociative.

Definition at line 96 of file base.cc.

References addr, and tagShift.

Referenced by BaseTags::extractTag().

◆ getEntry()

ReplaceableEntry * BaseIndexingPolicy::getEntry ( const uint32_t  set,
const uint32_t  way 
) const

Get an entry based on its set and way.

All entries must have been set already before calling this function.

Parameters
setThe set of the desired entry.
wayThe way of the desired entry.
Returns
entry The entry pointer.

Definition at line 72 of file base.cc.

References sets.

Referenced by BaseTags::findBlockBySetAndWay().

◆ getPossibleEntries()

virtual std::vector<ReplaceableEntry*> BaseIndexingPolicy::getPossibleEntries ( const Addr  addr) const
pure virtual

Find all possible entries for insertion and replacement of an address.

Should be called immediately before ReplacementPolicy's findVictim() not to break cache resizing.

Parameters
addrThe addr to a find possible entries for.
Returns
The possible entries.

Implemented in SkewedAssociative, and SetAssociative.

Referenced by SectorTags::findBlock(), BaseTags::findBlock(), CompressedTags::findVictim(), BaseSetAssoc::findVictim(), and SectorTags::findVictim().

◆ regenerateAddr()

virtual Addr BaseIndexingPolicy::regenerateAddr ( const Addr  tag,
const ReplaceableEntry entry 
) const
pure virtual

Regenerate an entry's address from its tag and assigned indexing bits.

Parameters
tagThe tag bits.
entryThe entry.
Returns
the entry's original address.

Implemented in SkewedAssociative, and SetAssociative.

Referenced by SectorTags::regenerateBlkAddr(), and BaseSetAssoc::regenerateBlkAddr().

◆ setEntry()

void BaseIndexingPolicy::setEntry ( ReplaceableEntry entry,
const uint64_t  index 
)

Associate a pointer to an entry to its physical counterpart.

Parameters
entryThe entry pointer.
indexAn unique index for the entry.

Definition at line 78 of file base.cc.

References assoc, MipsISA::index, numSets, ReplaceableEntry::setPosition(), and sets.

Referenced by AssociativeSet< Prefetcher::IrregularStreamBuffer::AddressMappingEntry >::AssociativeSet(), CompressedTags::tagsInit(), BaseSetAssoc::tagsInit(), and SectorTags::tagsInit().

Member Data Documentation

◆ assoc

const unsigned BaseIndexingPolicy::assoc
protected

◆ numSets

const uint32_t BaseIndexingPolicy::numSets
protected

The number of sets in the cache.

Definition at line 74 of file base.hh.

Referenced by BaseIndexingPolicy(), setEntry(), and SkewedAssociative::SkewedAssociative().

◆ setMask

const unsigned BaseIndexingPolicy::setMask
protected

Mask out all bits that aren't part of the set index.

Definition at line 84 of file base.hh.

Referenced by Prefetcher::StridePrefetcherHashedSetAssociative::extractSet(), SetAssociative::extractSet(), SkewedAssociative::extractSet(), and SkewedAssociative::regenerateAddr().

◆ sets

std::vector<std::vector<ReplaceableEntry*> > BaseIndexingPolicy::sets
protected

◆ setShift

const int BaseIndexingPolicy::setShift
protected

◆ tagShift

const int BaseIndexingPolicy::tagShift
protected

The amount to shift the address to get the tag.

Definition at line 94 of file base.hh.

Referenced by Prefetcher::StridePrefetcherHashedSetAssociative::extractSet(), extractTag(), SetAssociative::regenerateAddr(), and SkewedAssociative::regenerateAddr().


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

Generated on Wed Sep 30 2020 14:02:21 for gem5 by doxygen 1.8.17