org.mmtk.plan.refcount.generational

Class GenRCFindRootSetTraceLocal

java.lang.Object

org.mmtk.plan.TransitiveClosure

org.mmtk.plan.TraceLocal

org.mmtk.plan.refcount.generational.GenRCFindRootSetTraceLocal

public final class GenRCFindRootSetTraceLocal
extends TraceLocal

This class implements the thread-local core functionality for a transitive closure over the heap graph.

Field Summary

Fields

Modifier and Type	Field and Description
private ObjectReferenceDeque	rootBuffer

Fields inherited from class org.mmtk.plan.TraceLocal

rootLocations, values

Fields inherited from class org.mmtk.plan.TransitiveClosure

specializedScan

Constructor Summary

Constructors

Constructor and Description
GenRCFindRootSetTraceLocal(Trace trace, ObjectReferenceDeque rootBuffer)

Method Summary

Modifier and Type	Method and Description
boolean	isLive(ObjectReference object) Is the specified object reachable?
ObjectReference	traceObject(ObjectReference object) When we trace a non-root object we do nothing.
ObjectReference	traceObject(ObjectReference object, boolean root) When we trace a root object we remember it.
boolean	willNotMoveInCurrentCollection(ObjectReference object) Ensure that the referenced object will not move from this point through to the end of the collection.

Methods inherited from class org.mmtk.plan.TraceLocal

completeTrace, flush, getForwardedFinalizable, getForwardedReference, getForwardedReferenceType, getForwardedReferent, incrementalTrace, isReachable, isReferentLive, logMessage, overwriteReferenceDuringTrace, prepare, processEdge, processInteriorEdge, processNode, processRememberedSets, processRootEdge, processRoots, readyToFinalize, release, reportDelayedRootEdge, retainForFinalize, retainReferent, scanObject

Methods inherited from class org.mmtk.plan.TransitiveClosure

getSpecializedScanClass, registerSpecializedScan

Methods inherited from class java.lang.Object

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

Field Detail

rootBuffer

private final ObjectReferenceDeque rootBuffer

Constructor Detail

GenRCFindRootSetTraceLocal

public GenRCFindRootSetTraceLocal(Trace trace,
                                  ObjectReferenceDeque rootBuffer)

Method Detail

isLive

public boolean isLive(ObjectReference object)

Is the specified object reachable?

Overrides:

isLive in class TraceLocal

Parameters:

object - The object.

Returns:

true if the object is reachable.

traceObject

public ObjectReference traceObject(ObjectReference object)

When we trace a non-root object we do nothing.

Overrides:

traceObject in class TraceLocal

Parameters:

object - The object to be traced.

Returns:

The new reference to the same object instance.

traceObject

public ObjectReference traceObject(ObjectReference object,
                                   boolean root)

When we trace a root object we remember it.

Overrides:

traceObject in class TraceLocal

Parameters:

object - The object to be traced.

root - Is this object a root?

Returns:

The new reference to the same object instance.

willNotMoveInCurrentCollection

public boolean willNotMoveInCurrentCollection(ObjectReference object)

Description copied from class: TraceLocal

Ensure that the referenced object will not move from this point through to the end of the collection. This can involve forwarding the object if necessary. Non-copying collectors do nothing, copying collectors must override this method in each of their trace classes.

Overrides:

willNotMoveInCurrentCollection in class TraceLocal

Parameters:

object - The object that must not move during the collection.

Returns:

true If the object will not move during collection