org.mmtk.policy.immix
Class ObjectHeader

java.lang.Object
  org.mmtk.policy.immix.ObjectHeader

public class ObjectHeader
extends Object

AVAILABLE_LOCAL_BITS

static final int AVAILABLE_LOCAL_BITS

number of header bits we may use

LOCAL_GC_BITS_REQUIRED

public static final int LOCAL_GC_BITS_REQUIRED

GLOBAL_GC_BITS_REQUIRED

public static final int GLOBAL_GC_BITS_REQUIRED

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GC_HEADER_WORDS_REQUIRED

public static final int GC_HEADER_WORDS_REQUIRED

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NEW_OBJECT_MARK

static final byte NEW_OBJECT_MARK

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PINNED_BIT_NUMBER

public static final int PINNED_BIT_NUMBER

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PINNED_BIT

public static final byte PINNED_BIT

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STRADDLE_BIT_NUMBER

private static final int STRADDLE_BIT_NUMBER

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STRADDLE_BIT

public static final byte STRADDLE_BIT

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MARK_BASE

private static final int MARK_BASE

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MAX_MARKCOUNT_BITS

static final int MAX_MARKCOUNT_BITS

MARK_INCREMENT

private static final byte MARK_INCREMENT

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MARK_MASK

public static final byte MARK_MASK

MARK_AND_FORWARDING_MASK

private static final byte MARK_AND_FORWARDING_MASK

MARK_BASE_VALUE

public static final byte MARK_BASE_VALUE

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ObjectHeader

public ObjectHeader()

testAndMark

static byte testAndMark(ObjectReference object,
                        byte markState)

Non-atomically test and set the mark bit of an object.

Parameters:

object - The object whose mark bit is to be written

markState - The value to which the mark bits will be set

Returns:

the old mark state

setMarkStateUnlogAndUnlock

static void setMarkStateUnlogAndUnlock(ObjectReference object,
                                       byte gcByte,
                                       byte markState)

testMarkState

static boolean testMarkState(ObjectReference object,
                             byte value)

Return true if the mark count for an object has the given value.

Parameters:

object - The object whose mark bit is to be tested

value - The value against which the mark bit will be tested

Returns:

true if the mark bit for the object has the given value.

testMarkState

static boolean testMarkState(byte gcByte,
                             byte value)

isNewObject

static boolean isNewObject(ObjectReference object)

isMatureObject

static boolean isMatureObject(ObjectReference object)

markAsStraddling

static void markAsStraddling(ObjectReference object)

isStraddlingObject

static boolean isStraddlingObject(ObjectReference object)

pinObject

public static void pinObject(ObjectReference object)

isPinnedObject

static boolean isPinnedObject(ObjectReference object)

writeMarkState

static void writeMarkState(ObjectReference object,
                           byte markState,
                           boolean straddle)

Write the allocState into the mark state fields of an object non-atomically. This is appropriate for collection time initialization.

Parameters:

object - The object whose mark state is to be written

markState - TODO: what am I?

straddle - TODO: what am I?

returnToPriorStateAndEnsureUnlogged

static void returnToPriorStateAndEnsureUnlogged(ObjectReference object,
                                                byte status)

deltaMarkState

static byte deltaMarkState(byte state,
                           boolean increment)

Return the mark state incremented or decremented by one.

Parameters:

increment - If true, then return the incremented value else return the decremented value

Returns:

the mark state incremented or decremented by one.