org.mmtk.plan.refcount

Class RCBaseConstraints

java.lang.Object

org.mmtk.plan.PlanConstraints

org.mmtk.plan.SimpleConstraints

org.mmtk.plan.StopTheWorldConstraints

org.mmtk.plan.refcount.RCBaseConstraints

Direct Known Subclasses:

GenRCConstraints, RCConstraints

public class RCBaseConstraints
extends StopTheWorldConstraints

This class and its subclasses communicate to the host VM/Runtime any features of the selected plan that it needs to know. This is separate from the main Plan/PlanLocal class in order to bypass any issues with ordering of static initialization.

Constructor Summary

Constructors

Constructor and Description
RCBaseConstraints()

Method Summary

Modifier and Type	Method and Description
boolean	buildForGenRC()
int	gcHeaderBits()
int	gcHeaderWords()
int	maxNonLOSDefaultAllocBytes()
boolean	needsObjectReferenceWriteBarrier()
boolean	objectReferenceBulkCopySupported()

Methods inherited from class org.mmtk.plan.PlanConstraints

addressBulkCopySupported, booleanBulkCopySupported, byteBulkCopySupported, charBulkCopySupported, doubleBulkCopySupported, extentBulkCopySupported, floatBulkCopySupported, generateGCTrace, generational, intBulkCopySupported, longBulkCopySupported, maxNonLOSCopyBytes, maxNonLOSNonMovingAllocBytes, maxNumGCThreads, movesObjects, needsAddressReadBarrier, needsAddressWriteBarrier, needsBooleanReadBarrier, needsBooleanWriteBarrier, needsByteReadBarrier, needsByteWriteBarrier, needsCharReadBarrier, needsCharWriteBarrier, needsConcurrentWorkers, needsDoubleReadBarrier, needsDoubleWriteBarrier, needsExtentReadBarrier, needsExtentWriteBarrier, needsFloatReadBarrier, needsFloatWriteBarrier, needsForwardAfterLiveness, needsIntReadBarrier, needsIntWriteBarrier, needsJavaLangReferenceReadBarrier, needsLinearScan, needsLogBitInHeader, needsLongReadBarrier, needsLongWriteBarrier, needsObjectReferenceNonHeapReadBarrier, needsObjectReferenceNonHeapWriteBarrier, needsObjectReferenceReadBarrier, needsOffsetReadBarrier, needsOffsetWriteBarrier, needsShortReadBarrier, needsShortWriteBarrier, needsWordReadBarrier, needsWordWriteBarrier, numSpecializedScans, offsetBulkCopySupported, shortBulkCopySupported, withGCspy, wordBulkCopySupported

Methods inherited from class java.lang.Object

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

Constructor Detail

RCBaseConstraints

public RCBaseConstraints()

Method Detail

gcHeaderBits

public int gcHeaderBits()

Specified by:

gcHeaderBits in class PlanConstraints

Returns:

The number of header bits that are required.

gcHeaderWords

public int gcHeaderWords()

Specified by:

gcHeaderWords in class PlanConstraints

Returns:

The number of header words that are required.

needsObjectReferenceWriteBarrier

public boolean needsObjectReferenceWriteBarrier()

Overrides:

needsObjectReferenceWriteBarrier in class PlanConstraints

Returns:

true if this Plan requires write barriers on object references.

maxNonLOSDefaultAllocBytes

public int maxNonLOSDefaultAllocBytes()

Overrides:

maxNonLOSDefaultAllocBytes in class PlanConstraints

Returns:

Size (in bytes) beyond which new regular objects must be allocated to the LOS

objectReferenceBulkCopySupported

public boolean objectReferenceBulkCopySupported()

Overrides:

objectReferenceBulkCopySupported in class PlanConstraints

Returns:

true if this Plan can perform bulk object arraycopy barriers.

buildForGenRC

public boolean buildForGenRC()

Returns:

true if we are building for generational reference counting