A superblock is composed of sub-blocks, and each sub-block has information regarding its superblock and a pointer to its superblock tag. More...

#include <super_blk.hh>

Inheritance diagram for gem5::CompressionBlk:

Public Types
enum	OverwriteType : int { DATA_CONTRACTION = -1 , UNCHANGED = 0 , DATA_EXPANSION = 1 }
	When an overwrite happens, the data size may change an not fit in its current container any longer. More...

Public Types inherited from gem5::CacheBlk
enum	CoherenceBits : unsigned { WritableBit = 0x02 , ReadableBit = 0x04 , DirtyBit = 0x08 , AllBits = 0x0E }
	Cache block's enum listing the supported coherence bits. More...

Public Member Functions
	CompressionBlk ()

	CompressionBlk (const CompressionBlk &)=delete

CompressionBlk &	operator= (const CompressionBlk &)=delete

	CompressionBlk (CompressionBlk &&)=delete

CompressionBlk &	operator= (CompressionBlk &&other)
	Move assignment operator.

CacheBlk &	operator= (CacheBlk &&other) override
	Move assignment operator.

	~CompressionBlk ()=default

bool	isCompressed () const
	Check if this block holds compressed data.

void	setCompressed ()
	Set compression bit.

void	setUncompressed ()
	Clear compression bit.

std::size_t	getSizeBits () const

void	setSizeBits (const std::size_t size)
	Set size, in bits, of this compressed block's data.

Cycles	getDecompressionLatency () const
	Get number of cycles needed to decompress this block.

void	setDecompressionLatency (const Cycles lat)
	Set number of cycles needed to decompress this block.

void	invalidate () override
	Invalidate the block and clear all state.

OverwriteType	checkExpansionContraction (const std::size_t size) const
	Determines if changing the size of the block will cause a data expansion (new size is bigger) or contraction (new size is smaller).

std::string	print () const override
	Pretty-print sector offset and other CacheBlk information.

Public Member Functions inherited from gem5::SectorSubBlk
	SectorSubBlk ()

	SectorSubBlk (const SectorSubBlk &)=delete

SectorSubBlk &	operator= (const SectorSubBlk &)=delete

	SectorSubBlk (SectorSubBlk &&)=delete

SectorSubBlk &	operator= (SectorSubBlk &&other)=default
	Move assignment operator.

	~SectorSubBlk ()=default

void	setSectorBlock (SectorBlk *sector_blk)
	Set sector block associated to this block.

SectorBlk *	getSectorBlock () const
	Get sector block associated to this block.

void	setSectorOffset (const int sector_offset)
	Set offset of this sub-block within the sector.

int	getSectorOffset () const
	Get offset of this sub-block within the sector.

Addr	getTag () const override
	Get tag associated to this block.

void	setValid () override
	Set valid bit and inform sector block.

void	insert (const Addr tag, const bool is_secure) override
	Insert the block by assigning it a tag and marking it valid.

void	invalidate () override
	Invalidate the block and inform sector block.

std::string	print () const override
	Pretty-print sector offset and other CacheBlk information.

CacheBlk &	operator= (const CacheBlk &)=delete

virtual CacheBlk &	operator= (CacheBlk &&other)
	Move assignment operator.

Public Member Functions inherited from gem5::CacheBlk
	CacheBlk ()

	CacheBlk (const CacheBlk &)=delete

CacheBlk &	operator= (const CacheBlk &)=delete

	CacheBlk (const CacheBlk &&)=delete

virtual	~CacheBlk ()

void	setCoherenceBits (unsigned bits)
	Sets the corresponding coherence bits.

void	clearCoherenceBits (unsigned bits)
	Clear the corresponding coherence bits.

bool	isSet (unsigned bits) const
	Checks the given coherence bits are set.

bool	wasPrefetched () const
	Check if this block was the result of a hardware prefetch, yet to be touched.

void	clearPrefetched ()
	Clear the prefetching bit.

void	setPrefetched ()
	Marks this blocks as a recently prefetched block.

Tick	getWhenReady () const
	Get tick at which block's data will be available for access.

void	setWhenReady (const Tick tick)
	Set tick at which block's data will be available for access.

uint32_t	getTaskId () const
	Get the task id associated to this block.

uint32_t	getSrcRequestorId () const
	Get the requestor id associated to this block.

uint64_t	getPartitionId () const
	Getter for _partitionId.

unsigned	getRefCount () const
	Get the number of references to this block since insertion.

void	increaseRefCount ()
	Get the number of references to this block since insertion.

Tick	getAge () const
	Get the block's age, that is, the number of ticks since its insertion.

void	insert (const Addr tag, const bool is_secure, const int src_requestor_ID, const uint32_t task_ID, const uint64_t partition_id)
	Set member variables when a block insertion occurs.

void	trackLoadLocked (PacketPtr pkt)
	Track the fact that a local locked was issued to the block.

void	clearLoadLocks (const RequestPtr &req)
	Clear the any load lock that intersect the request, and is from a different context.

bool	checkWrite (PacketPtr pkt)
	Handle interaction of load-locked operations and stores.

void	insert (const Addr tag) override
	Insert the block by assigning it a tag and marking it valid.

Public Member Functions inherited from gem5::TaggedEntry
	TaggedEntry ()

	~TaggedEntry ()=default

bool	isSecure () const
	Check if this block holds data from the secure memory space.

virtual bool	matchTag (Addr tag, bool is_secure) const
	Checks if the given tag information corresponds to this entry's.

void	invalidate () override
	Invalidate the block.

std::string	print () const override
	Prints relevant information about this entry.

bool	matchTag (const Addr tag) const override
	Checks if the given tag information corresponds to this entry's.

void	insert (const Addr tag) override
	Insert the block by assigning it a tag and marking it valid.

Public Member Functions inherited from gem5::CacheEntry
	CacheEntry ()=default

	~CacheEntry ()=default

virtual bool	isValid () const
	Checks if the entry is valid.

Public Member Functions inherited from gem5::ReplaceableEntry
	ReplaceableEntry ()

virtual	~ReplaceableEntry ()=default

virtual void	setPosition (const uint32_t set, const uint32_t way)
	Set both the set and way.

uint32_t	getSet () const
	Get set number.

uint32_t	getWay () const
	Get way number.

Private Attributes
std::size_t	_size
	Set size, in bits, of this compressed block's data.

Cycles	_decompressionLatency
	Number of cycles needed to decompress this block.

bool	_compressed
	Compression bit.

Additional Inherited Members
Public Attributes inherited from gem5::CacheBlk
uint8_t *	data = nullptr
	Contains a copy of the data in this block for easy access.

Tick	whenReady = 0
	Which curTick() will this block be accessible.

Public Attributes inherited from gem5::ReplaceableEntry
std::shared_ptr< replacement_policy::ReplacementData >	replacementData
	Replacement data associated to this entry.

Protected Member Functions inherited from gem5::CacheBlk
void	setTaskId (const uint32_t task_id)
	Set the task id value.

void	setSrcRequestorId (const uint32_t id)
	Set the source requestor id.

void	setPartitionId (const uint64_t partitionId)
	Setter for _partitionId.

void	setRefCount (const unsigned count)
	Set the number of references to this block since insertion.

void	setTickInserted ()
	Set the current tick as this block's insertion tick.

Protected Member Functions inherited from gem5::TaggedEntry
virtual void	setSecure ()
	Set secure bit.

Protected Member Functions inherited from gem5::CacheEntry
virtual void	setTag (Addr _tag)
	Set tag associated to this block.

Protected Attributes inherited from gem5::SectorSubBlk
SectorBlk *	_sectorBlk
	Sector block associated to this block.

int	_sectorOffset
	The offset of this sub-block in the sector.

Protected Attributes inherited from gem5::CacheBlk
std::list< Lock >	lockList
	List of thread contexts that have performed a load-locked (LL) on the block since the last store.

unsigned	coherence
	The current coherence status of this block.

Protected Attributes inherited from gem5::ReplaceableEntry
uint32_t	_set
	Set to which this entry belongs.

uint32_t	_way
	Way (relative position within the set) to which this entry belongs.

Detailed Description

A superblock is composed of sub-blocks, and each sub-block has information regarding its superblock and a pointer to its superblock tag.

A superblock can be seen as a variation of a sector block, and therefore we use a sector nomenclature.

Definition at line 51 of file super_blk.hh.

Member Enumeration Documentation

◆ OverwriteType

enum gem5::CompressionBlk::OverwriteType : int

When an overwrite happens, the data size may change an not fit in its current container any longer.

This enum declared which kind of size change happened in this situation.

Enumerator
DATA_CONTRACTION	New data contents are considered smaller than previous contents.
UNCHANGED	New and old contents are considered of similar sizes.
DATA_EXPANSION	New data contents are considered larger than previous contents.

Definition at line 74 of file super_blk.hh.

Constructor & Destructor Documentation

◆ CompressionBlk() [1/3]

gem5::CompressionBlk::CompressionBlk ( )

Definition at line 45 of file super_blk.cc.

◆ CompressionBlk() [2/3]

gem5::CompressionBlk::CompressionBlk ( const CompressionBlk & )

delete

◆ CompressionBlk() [3/3]

gem5::CompressionBlk::CompressionBlk ( CompressionBlk && )

delete

◆ ~CompressionBlk()

gem5::CompressionBlk::~CompressionBlk ( )

default

Member Function Documentation

◆ checkExpansionContraction()

CompressionBlk::OverwriteType gem5::CompressionBlk::checkExpansionContraction ( const std::size_t size ) const

Determines if changing the size of the block will cause a data expansion (new size is bigger) or contraction (new size is smaller).

Sizes are not necessarily compared at at bit granularities (e.g., 20 bits is considered equal to 23 bits when blocks use 32-bit spaces as minimum allocation units).

Parameters

size	The new compressed size.

Returns: Type of size change.

See also: OverwriteType.

Definition at line 148 of file super_blk.cc.

References gem5::SuperBlk::calculateCompressionFactor(), DATA_CONTRACTION, DATA_EXPANSION, gem5::SuperBlk::getCompressionFactor(), gem5::SectorSubBlk::getSectorBlock(), and UNCHANGED.

Referenced by gem5::BaseCache::updateCompressionData().

◆ getDecompressionLatency()

Cycles gem5::CompressionBlk::getDecompressionLatency ( ) const

Get number of cycles needed to decompress this block.

Returns: Decompression latency.

Definition at line 129 of file super_blk.cc.

References _decompressionLatency.

Referenced by gem5::compression::Base::getDecompressionLatency(), and print().

◆ getSizeBits()

std::size_t gem5::CompressionBlk::getSizeBits ( ) const

Definition at line 93 of file super_blk.cc.

References _size.

Referenced by print(), and gem5::BaseCache::updateCompressionData().

◆ invalidate()

void gem5::CompressionBlk::invalidate ( )

overridevirtual

Invalidate the block and clear all state.

Reimplemented from gem5::CacheBlk.

Definition at line 141 of file super_blk.cc.

References gem5::SectorSubBlk::invalidate(), and setUncompressed().

◆ isCompressed()

bool gem5::CompressionBlk::isCompressed ( ) const

Check if this block holds compressed data.

Returns: True if the block holds compressed data.

Definition at line 75 of file super_blk.cc.

References _compressed.

Referenced by gem5::compression::Base::getDecompressionLatency(), and print().

◆ operator=() [1/3]

CacheBlk & gem5::CompressionBlk::operator= ( CacheBlk && other )

overridevirtual

Move assignment operator.

This should only be used to move an existing valid entry into an invalid one, not to create a new entry. In the end the valid entry will become invalid, and the invalid, valid. All location related variables will remain the same, that is, an entry cannot move its data, just its metadata contents.

Reimplemented from gem5::CacheBlk.

Definition at line 51 of file super_blk.cc.

References operator=().

◆ operator=() [2/3]

CompressionBlk & gem5::CompressionBlk::operator= ( CompressionBlk && other )

Move assignment operator.

This should only be used to move an existing valid entry into an invalid one, not to create a new entry. In the end the valid entry will become invalid, and the invalid, valid. All location related variables will remain the same.

Definition at line 58 of file super_blk.cc.

References gem5::CacheBlk::operator=(), setCompressed(), setDecompressionLatency(), and setUncompressed().

◆ operator=() [3/3]

CompressionBlk & gem5::CompressionBlk::operator= ( const CompressionBlk & )

delete

Referenced by operator=().

◆ print()

std::string gem5::CompressionBlk::print ( ) const

overridevirtual

Pretty-print sector offset and other CacheBlk information.

Returns: string with basic state information

Reimplemented from gem5::CacheBlk.

Definition at line 164 of file super_blk.cc.

References gem5::csprintf(), getDecompressionLatency(), getSizeBits(), isCompressed(), and gem5::SectorSubBlk::print().

Referenced by gem5::compression::Base::getDecompressionLatency().

◆ setCompressed()

void gem5::CompressionBlk::setCompressed ( )

Set compression bit.

Definition at line 81 of file super_blk.cc.

References _compressed.

Referenced by operator=(), and setSizeBits().

◆ setDecompressionLatency()

void gem5::CompressionBlk::setDecompressionLatency ( const Cycles lat )

Set number of cycles needed to decompress this block.

Parameters

Decompression latency.

Definition at line 135 of file super_blk.cc.

References _decompressionLatency.

Referenced by operator=(), and gem5::BaseCache::updateCompressionData().

◆ setSizeBits()

void gem5::CompressionBlk::setSizeBits ( const std::size_t size )

Set size, in bits, of this compressed block's data.

Parameters

The	compressed size.

Definition at line 99 of file super_blk.cc.

References _size, gem5::SuperBlk::calculateCompressionFactor(), gem5::SectorBlk::getNumValid(), gem5::SectorSubBlk::getSectorBlock(), gem5::SuperBlk::isCompressed(), setCompressed(), gem5::SuperBlk::setCompressionFactor(), and setUncompressed().

Referenced by gem5::BaseCache::updateCompressionData().

◆ setUncompressed()

void gem5::CompressionBlk::setUncompressed ( )

Clear compression bit.

Definition at line 87 of file super_blk.cc.

References _compressed.

Referenced by invalidate(), operator=(), and setSizeBits().

Member Data Documentation

◆ _compressed

bool gem5::CompressionBlk::_compressed

private

Compression bit.

Definition at line 66 of file super_blk.hh.

Referenced by isCompressed(), setCompressed(), and setUncompressed().

◆ _decompressionLatency

Cycles gem5::CompressionBlk::_decompressionLatency

private

Number of cycles needed to decompress this block.

We store it to avoid doing decompressions.

Definition at line 63 of file super_blk.hh.

Referenced by getDecompressionLatency(), and setDecompressionLatency().

◆ _size

std::size_t gem5::CompressionBlk::_size

private

Set size, in bits, of this compressed block's data.

Definition at line 57 of file super_blk.hh.

Referenced by getSizeBits(), and setSizeBits().

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

mem/cache/tags/super_blk.hh
mem/cache/tags/super_blk.cc

Public Types

Public Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ OverwriteType

Constructor & Destructor Documentation

◆ CompressionBlk() [1/3]

◆ CompressionBlk() [2/3]

◆ CompressionBlk() [3/3]

◆ ~CompressionBlk()

Member Function Documentation

◆ checkExpansionContraction()

◆ getDecompressionLatency()

◆ getSizeBits()

◆ invalidate()

◆ isCompressed()

◆ operator=() [1/3]

◆ operator=() [2/3]

◆ operator=() [3/3]

◆ print()

◆ setCompressed()

◆ setDecompressionLatency()

◆ setSizeBits()

◆ setUncompressed()

Member Data Documentation

◆ _compressed

◆ _decompressionLatency

◆ _size