com.oracle.svm.core.hub

Class LayoutEncoding

java.lang.Object

com.oracle.svm.core.hub.LayoutEncoding

public class LayoutEncoding
extends Object

The layout encoding for instances is the aligned instance size (i.e., a positive number).

For arrays, the layout encoding is a negative number with the following format:
[tag:2, free:10, base:12, indexShift:8]

• tag: 0x80 if the array is an object array, 0xC0 if it is a primitive array
• free: currently unused bits
• base: the array base offset
• indexShift: the array index shift for accessing array elements or for computing the array size based on the array length

Constructor Summary

Constructors

Constructor and Description
LayoutEncoding()

Method Summary

Modifier and Type	Method and Description
static int	forAbstract()
static int	forArray(jdk.vm.ci.meta.ResolvedJavaType type, boolean isObject, int arrayBaseOffset, int arrayIndexShift)
static int	forInstance(jdk.vm.ci.meta.ResolvedJavaType type, int size)
static int	forInterface()
static int	forPrimitive()
protected static int	getAlignmentMask()
static org.graalvm.word.UnsignedWord	getArrayBaseOffset(int encoding)
static org.graalvm.word.UnsignedWord	getArrayElementOffset(int encoding, int index)
static int	getArrayIndexScale(int encoding)
static int	getArrayIndexShift(int encoding)
static org.graalvm.word.UnsignedWord	getArraySize(int encoding, int length)
static org.graalvm.word.UnsignedWord	getInstanceSize(int encoding)
static org.graalvm.word.Pointer	getObjectEnd(Object obj) Returns the end of the Object when the call started, e.g., for logging.
static org.graalvm.word.UnsignedWord	getSizeFromObject(Object obj)
static boolean	isAbstract(int encoding)
static boolean	isArray(int encoding)
static boolean	isArray(Object obj)
static boolean	isInstance(int encoding)
static boolean	isInstance(Object obj)
static boolean	isInterface(int encoding)
static boolean	isObjectArray(int encoding)
static boolean	isPrimitive(int encoding)
static boolean	isPrimitiveArray(int encoding)

Methods inherited from class java.lang.Object

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

Constructor Detail

LayoutEncoding

public LayoutEncoding()

Method Detail

forPrimitive

public static int forPrimitive()

forInterface

public static int forInterface()

forAbstract

public static int forAbstract()

forInstance

public static int forInstance(jdk.vm.ci.meta.ResolvedJavaType type,
                              int size)

forArray

public static int forArray(jdk.vm.ci.meta.ResolvedJavaType type,
                           boolean isObject,
                           int arrayBaseOffset,
                           int arrayIndexShift)

isPrimitive

public static boolean isPrimitive(int encoding)

isInterface

public static boolean isInterface(int encoding)

isAbstract

public static boolean isAbstract(int encoding)

isInstance

public static boolean isInstance(int encoding)

getInstanceSize

public static org.graalvm.word.UnsignedWord getInstanceSize(int encoding)

isArray

public static boolean isArray(int encoding)

isPrimitiveArray

public static boolean isPrimitiveArray(int encoding)

isObjectArray

public static boolean isObjectArray(int encoding)

getArrayBaseOffset

public static org.graalvm.word.UnsignedWord getArrayBaseOffset(int encoding)

getArrayIndexShift

public static int getArrayIndexShift(int encoding)

getArrayIndexScale

public static int getArrayIndexScale(int encoding)

getArrayElementOffset

public static org.graalvm.word.UnsignedWord getArrayElementOffset(int encoding,
                                                                  int index)

getArraySize

public static org.graalvm.word.UnsignedWord getArraySize(int encoding,
                                                         int length)

getSizeFromObject

public static org.graalvm.word.UnsignedWord getSizeFromObject(Object obj)

getObjectEnd

public static org.graalvm.word.Pointer getObjectEnd(Object obj)

Returns the end of the Object when the call started, e.g., for logging.

isArray

public static boolean isArray(Object obj)

isInstance

public static boolean isInstance(Object obj)

getAlignmentMask

protected static int getAlignmentMask()