org.jikesrvm.mm.mmtk

Class TraceInterface

java.lang.Object

org.mmtk.vm.TraceInterface

org.jikesrvm.mm.mmtk.TraceInterface

public final class TraceInterface
extends TraceInterface

Class that supports scanning Objects or Arrays for references during tracing, handling those references, and computing death times

Field Summary

Fields

Modifier and Type	Field and Description
private static byte[][]	allocCallMethods

Constructor Summary

Constructors

Constructor and Description
TraceInterface()

Method Summary

Modifier and Type	Method and Description
Offset	adjustSlotOffset(boolean isScalar, ObjectReference src, Address slot) This adjusts the offset into an object to reflect what it would look like if the fields were laid out in memory space immediately after the object pointer.
boolean	gcEnabled() Returns true if the VM is ready for a garbage collection.
Address	getBootImageLink()
Word	getDeathTime(ObjectReference ref)
int	getHeaderEndOffset()
int	getHeaderSize()
ObjectReference	getLink(ObjectReference ref)
Word	getOID()
Word	getOID(ObjectReference ref)
private boolean	isAllocCall(byte[] name) Given a method name, determine if it is a "real" method or one used for allocation/tracing.
void	setDeathTime(ObjectReference ref, Word time_)
void	setLink(ObjectReference ref, ObjectReference link)
void	setOID(Word oid)
Address	skipOwnFramesAndDump(ObjectReference typeRef) This skips over the frames added by the tracing algorithm, outputs information identifying the method the containts the "new" call triggering the allocation, and returns the address of the first non-trace, non-alloc stack frame.
void	updateDeathTime(ObjectReference obj) Update an object's death time.
void	updateTime(Word time_)

Methods inherited from class java.lang.Object

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

Field Detail

allocCallMethods

private static byte[][] allocCallMethods

Constructor Detail

TraceInterface

public TraceInterface()

Method Detail

gcEnabled

public boolean gcEnabled()

Returns true if the VM is ready for a garbage collection.

Specified by:

gcEnabled in class TraceInterface

Returns:

true if the VM is ready for GC, false otherwise.

isAllocCall

private boolean isAllocCall(byte[] name)

Given a method name, determine if it is a "real" method or one used for allocation/tracing.

Parameters:

name - The method name to test as an array of bytes

Returns:

true if the method is a "real" method, false otherwise.

adjustSlotOffset

public Offset adjustSlotOffset(boolean isScalar,
                               ObjectReference src,
                               Address slot)

Description copied from class: TraceInterface

This adjusts the offset into an object to reflect what it would look like if the fields were laid out in memory space immediately after the object pointer.

Specified by:

adjustSlotOffset in class TraceInterface

Parameters:

isScalar - If this is a pointer store to a scalar object

src - The address of the source object

slot - The address within src into which the update will be stored

Returns:

The easy to understand offset of the slot

skipOwnFramesAndDump

public Address skipOwnFramesAndDump(ObjectReference typeRef)

Description copied from class: TraceInterface

This skips over the frames added by the tracing algorithm, outputs information identifying the method the containts the "new" call triggering the allocation, and returns the address of the first non-trace, non-alloc stack frame.

Specified by:

skipOwnFramesAndDump in class TraceInterface

Parameters:

typeRef - The type reference (tib) of the object just allocated

Returns:

The frame pointer address for the method that allocated the object

updateDeathTime

public void updateDeathTime(ObjectReference obj)

Update an object's death time.

Specified by:

updateDeathTime in class TraceInterface

Parameters:

obj - the object

setDeathTime

public void setDeathTime(ObjectReference ref,
                         Word time_)

Specified by:

setDeathTime in class TraceInterface

setLink

public void setLink(ObjectReference ref,
                    ObjectReference link)

Specified by:

setLink in class TraceInterface

updateTime

public void updateTime(Word time_)

Specified by:

updateTime in class TraceInterface

getOID

public Word getOID(ObjectReference ref)

Specified by:

getOID in class TraceInterface

getDeathTime

public Word getDeathTime(ObjectReference ref)

Specified by:

getDeathTime in class TraceInterface

getLink

public ObjectReference getLink(ObjectReference ref)

Specified by:

getLink in class TraceInterface

getBootImageLink

public Address getBootImageLink()

Specified by:

getBootImageLink in class TraceInterface

getOID

public Word getOID()

Specified by:

getOID in class TraceInterface

setOID

public void setOID(Word oid)

Specified by:

setOID in class TraceInterface

getHeaderSize

public int getHeaderSize()

Specified by:

getHeaderSize in class TraceInterface

getHeaderEndOffset

public int getHeaderEndOffset()

Specified by:

getHeaderEndOffset in class TraceInterface