org.mmtk.plan.generational

Class GenMatureTraceLocal

java.lang.Object

org.mmtk.plan.TransitiveClosure

org.mmtk.plan.TraceLocal

org.mmtk.plan.generational.GenMatureTraceLocal

Direct Known Subclasses:

GenCopyMatureTraceLocal, GenImmixMatureDefragTraceLocal, GenImmixMatureTraceLocal, GenMSMatureTraceLocal

public abstract class GenMatureTraceLocal
extends TraceLocal

This abstract class implements the core functionality for a transitive closure over the heap graph.

Field Summary

Fields

Modifier and Type	Field and Description
private AddressPairDeque	arrayRemset
private ObjectReferenceDeque	modbuf
private AddressDeque	remset

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
GenMatureTraceLocal(int specializedScan, Trace trace, GenCollector plan)
GenMatureTraceLocal(Trace trace, GenCollector plan)

Method Summary

Modifier and Type	Method and Description
boolean	isLive(ObjectReference object) Is the specified object live?
protected void	processRememberedSets() Process any remembered set entries.
ObjectReference	traceObject(ObjectReference object) This method is the core method during the trace of the object graph.
boolean	willNotMoveInCurrentCollection(ObjectReference object) Return true if this object is guaranteed not to move during this collection (i.e. this object is definitely not an unforwarded object).

Methods inherited from class org.mmtk.plan.TraceLocal

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

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

modbuf

private final ObjectReferenceDeque modbuf

remset

private final AddressDeque remset

arrayRemset

private final AddressPairDeque arrayRemset

Constructor Detail

GenMatureTraceLocal

public GenMatureTraceLocal(int specializedScan,
                           Trace trace,
                           GenCollector plan)

Parameters:

specializedScan - the id of the specialized scan

trace - the global trace class to use

plan - the state of the generational collector

GenMatureTraceLocal

public GenMatureTraceLocal(Trace trace,
                           GenCollector plan)

Parameters:

trace - the global trace class to use

plan - the state of the generational collector

Method Detail

isLive

public boolean isLive(ObjectReference object)

Is the specified object live?

Overrides:

isLive in class TraceLocal

Parameters:

object - The object.

Returns:

true if the object is live.

willNotMoveInCurrentCollection

public boolean willNotMoveInCurrentCollection(ObjectReference object)

Return true if this object is guaranteed not to move during this collection (i.e. this object is definitely not an unforwarded object).

Overrides:

willNotMoveInCurrentCollection in class TraceLocal

Parameters:

object - the object that might move

Returns:

true if this object is guaranteed not to move during this collection.

traceObject

public ObjectReference traceObject(ObjectReference object)

Description copied from class: TraceLocal

This method is the core method during the trace of the object graph. The role of this method is to:

1. Ensure the traced object is not collected.
2. If this is the first visit to the object enqueue it to be scanned.
3. Return the forwarded reference to the object.

Overrides:

traceObject in class TraceLocal

Parameters:

object - The object to be traced.

Returns:

The new reference to the same object instance.

processRememberedSets

protected void processRememberedSets()

Process any remembered set entries.

Overrides:

processRememberedSets in class TraceLocal