org.jikesrvm.objectmodel

Class FieldLayoutPacked.LayoutContext

java.lang.Object

org.jikesrvm.objectmodel.FieldLayoutContext

org.jikesrvm.objectmodel.FieldLayoutPacked.LayoutContext

Enclosing class:

FieldLayoutPacked

private static class FieldLayoutPacked.LayoutContext
extends FieldLayoutContext

Lay out an object, maintaining offsets of free slots of size 1,2,4 and 8 bytes.

Field Summary

Fields

Modifier and Type	Field and Description
private static int	LOG_MAX_SLOT_SIZE
private static int	MAX_SLOT_SIZE
private short	slot0
private short	slot1
private short	slot2

Fields inherited from class org.jikesrvm.objectmodel.FieldLayoutContext

OBJECT_SIZE_ALIGN

Constructor Summary

Constructors

Constructor and Description
LayoutContext(byte alignment, FieldLayoutPacked.LayoutContext superLayout) Create a layout for an object, initializing offsets from its superclass.

Method Summary

Modifier and Type	Method and Description
private short	get(int logSize)
(package private) int	nextOffset(int size, boolean isReference) Return the next available offset for a given size
private void	set(int logSize, int value)

Methods inherited from class org.jikesrvm.objectmodel.FieldLayoutContext

adjustAlignment, ensureObjectSize, getAlignment, getObjectSize, setObjectSize

Methods inherited from class java.lang.Object

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

Field Detail

LOG_MAX_SLOT_SIZE

private static final int LOG_MAX_SLOT_SIZE

See Also:

Constant Field Values

MAX_SLOT_SIZE

private static final int MAX_SLOT_SIZE

See Also:

Constant Field Values

slot0

private short slot0

slot1

private short slot1

slot2

private short slot2

Constructor Detail

LayoutContext

LayoutContext(byte alignment,
              FieldLayoutPacked.LayoutContext superLayout)

Create a layout for an object, initializing offsets from its superclass.

Parameters:

alignment - Current alignment of first field.

superLayout - Superclass layout context

Method Detail

get

private short get(int logSize)

set

private void set(int logSize,
                 int value)

nextOffset

int nextOffset(int size,
               boolean isReference)

Return the next available offset for a given size

Specified by:

nextOffset in class FieldLayoutContext

Parameters:

size - Size of the field to be laid out. Must be a power of 2.

isReference - whether the field is a reference field

Returns:

the offset of a new field of the given size