com.oracle.svm.core.genscavenge

Class GreyToBlackObjRefVisitor

java.lang.Object

com.oracle.svm.core.genscavenge.GreyToBlackObjRefVisitor

All Implemented Interfaces:

ObjectReferenceVisitor

public class GreyToBlackObjRefVisitor
extends Object
implements ObjectReferenceVisitor

This visitor is handed *Pointers to Object references* and if necessary it promotes the referenced Object and replaces the Object reference with a forwarding pointer. This turns an individual Object reference from grey to black. Since this visitor is used during collection, one instance of it is constructed during native image generation. The vanilla visitObjectReference method is not inlined, but there is a visitObjectReferenceInline available for performance critical code.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	GreyToBlackObjRefVisitor.Counters A set of counters.
static class	GreyToBlackObjRefVisitor.NoopCounters
static class	GreyToBlackObjRefVisitor.Options
static class	GreyToBlackObjRefVisitor.RealCounters

Field Summary

Fields

Modifier and Type	Field and Description
protected GreyToBlackObjRefVisitor.Counters	counters

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	GreyToBlackObjRefVisitor()

Method Summary

Modifier and Type	Method and Description
static GreyToBlackObjRefVisitor	factory()
protected GreyToBlackObjRefVisitor.Counters	getCounters()
GreyToBlackObjRefVisitor.Counters	openCounters()
boolean	visitObjectReference(org.graalvm.word.Pointer objRef, boolean compressed) Visit an Object reference.
boolean	visitObjectReferenceInline(org.graalvm.word.Pointer objRef, boolean compressed) This visitor is deals in *Pointers to Object references*.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.oracle.svm.core.heap.ObjectReferenceVisitor

epilogue, prologue

Field Detail

counters

protected final GreyToBlackObjRefVisitor.Counters counters

Constructor Detail

GreyToBlackObjRefVisitor

protected GreyToBlackObjRefVisitor()

Method Detail

factory

public static GreyToBlackObjRefVisitor factory()

visitObjectReference

public boolean visitObjectReference(org.graalvm.word.Pointer objRef,
                                    boolean compressed)

Description copied from interface: ObjectReferenceVisitor

Visit an Object reference. To get the corresponding Object reference.readObject can be used.

Specified by:

visitObjectReference in interface ObjectReferenceVisitor

Parameters:

objRef - The Object reference to be visited.

compressed - True if the reference is in compressed form, false otherwise.

Returns:

True if visiting should continue, false if visiting should stop.

visitObjectReferenceInline

public boolean visitObjectReferenceInline(org.graalvm.word.Pointer objRef,
                                          boolean compressed)

This visitor is deals in *Pointers to Object references*. As such it uses Pointer.readObject and Pointer.writeObject on the Pointer, not Pointer.toObject and Word.fromObject(o).

Specified by:

visitObjectReferenceInline in interface ObjectReferenceVisitor

getCounters

protected GreyToBlackObjRefVisitor.Counters getCounters()

openCounters

public GreyToBlackObjRefVisitor.Counters openCounters()