org.mmtk.utility.deque

Class ObjectReferenceBuffer

java.lang.Object

org.mmtk.plan.TransitiveClosure

org.mmtk.utility.deque.ObjectReferenceBuffer

Direct Known Subclasses:

RCDecBuffer

public abstract class ObjectReferenceBuffer
extends TransitiveClosure

This class is a combination of a Deque and a TraceStep, designed to include intelligent processing of child references as objects are scanned.

See Also:

TransitiveClosure

Field Summary

Fields

Modifier and Type	Field and Description
private ObjectReferenceDeque	values

Fields inherited from class org.mmtk.plan.TransitiveClosure

specializedScan

Constructor Summary

Constructors

Constructor and Description
ObjectReferenceBuffer(String name, SharedDeque queue) Constructor

Method Summary

Modifier and Type	Method and Description
void	flushLocal() Flushes all local state back to the shared queue.
boolean	isEmpty()
boolean	isFlushed()
ObjectReference	pop() Retrieves an object.
protected abstract void	process(ObjectReference object) This is the method that ensures
void	processChildren(ObjectReference object) Process each of the child objects for the passed object.
void	processEdge(ObjectReference source, Address slot) Trace an edge during GC.
void	push(ObjectReference object) Pushes an object onto the queue, forcing an inlined sequence.
void	pushOOL(ObjectReference object) Pushes an object onto the queue, forcing an out of line sequence.

Methods inherited from class org.mmtk.plan.TransitiveClosure

getSpecializedScanClass, processNode, registerSpecializedScan

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

values

private final ObjectReferenceDeque values

Constructor Detail

ObjectReferenceBuffer

public ObjectReferenceBuffer(String name,
                             SharedDeque queue)

Constructor

Parameters:

name - The name of the underlying deque.

queue - The shared deque that is used.

Method Detail

processEdge

public final void processEdge(ObjectReference source,
                              Address slot)

Description copied from class: TransitiveClosure

Trace an edge during GC.

Overrides:

processEdge in class TransitiveClosure

Parameters:

source - The source of the reference.

slot - The location containing the object reference.

process

protected abstract void process(ObjectReference object)

This is the method that ensures

Parameters:

object - The object to process.

processChildren

public final void processChildren(ObjectReference object)

Process each of the child objects for the passed object.

Parameters:

object - The object to process the children of.

push

public final void push(ObjectReference object)

Pushes an object onto the queue, forcing an inlined sequence.

Parameters:

object - The object to push.

pushOOL

public final void pushOOL(ObjectReference object)

Pushes an object onto the queue, forcing an out of line sequence.

Parameters:

object - The object to push.

pop

public final ObjectReference pop()

Retrieves an object.

Returns:

The object retrieved.

isEmpty

public final boolean isEmpty()

flushLocal

public final void flushLocal()

Flushes all local state back to the shared queue.

isFlushed

public final boolean isFlushed()

Returns:

true if this buffer is locally empty