com.oracle.svm.core.genscavenge

Class HeapImpl

java.lang.Object

com.oracle.svm.core.heap.Heap

com.oracle.svm.core.genscavenge.HeapImpl

public final class HeapImpl
extends Heap

Constructor Summary

Constructors

Constructor and Description
HeapImpl(int pageSize)

Method Summary

Modifier and Type	Method and Description
void	attachThread(org.graalvm.nativeimage.IsolateThread isolateThread) Notifies the heap that a new thread was attached to the VM.
org.graalvm.compiler.nodes.gc.BarrierSet	createBarrierSet(jdk.vm.ci.meta.MetaAccessProvider metaAccess) Returns a suitable BarrierSet for the garbage collector that is used for this heap.
void	detachThread(org.graalvm.nativeimage.IsolateThread isolateThread) Notifies the heap that a thread will be detached from the VM.
void	endSafepoint() Reset the heap to the normal execution state.
HeapAccounting	getAccounting()
protected List<Class<?>>	getAllClasses() Get all known classes.
Reference<?>	getAndClearReferencePendingList() Atomically get the list of pending references and clears (resets) it.
int	getClassCount() Returns the number of classes in the heap (initialized as well as uninitialized).
org.graalvm.word.UnsignedWord	getCommittedBytes()
GC	getGC()
static HeapImpl	getHeapImpl()
static ImageHeapInfo	getImageHeapInfo()
int	getImageHeapNullRegionSize() Returns the number of null bytes that should be prepended to the image heap during the image build.
int	getImageHeapOffsetInAddressSpace() Returns an offset relative to the heap base, at which the image heap should be mapped into the address space.
ObjectHeader	getObjectHeader() Get the ObjectHeader implementation that this Heap uses.
OldGeneration	getOldGeneration()
int	getPreferredAddressSpaceAlignment() Returns a multiple to which the heap address space should be aligned to at runtime.
RuntimeCodeInfoGCSupport	getRuntimeCodeInfoGCSupport()
org.graalvm.word.UnsignedWord	getUsedBytes()
YoungGeneration	getYoungGeneration()
boolean	hasReferencePendingList() Determines if the heap currently has Reference objects that are pending to be enqueued.
boolean	isAllocationDisallowed()
boolean	isInImageHeap(Object obj) Returns true if the given object is located in the image heap.
boolean	isInImageHeap(org.graalvm.word.Pointer objPointer) Returns true if the object at the given address is located in the image heap.
boolean	isInPrimaryImageHeap(Object obj) Whether the object is in the primary image heap, as opposed to an auxiliary image heap.
boolean	isInPrimaryImageHeap(org.graalvm.word.Pointer objPointer) Whether the object is in the primary image heap, as opposed to an auxiliary image heap.
void	optionValueChanged(RuntimeOptionKey<?> key) Notify the GC that the value of a GC-relevant option changed.
void	prepareForSafepoint() Prepare the heap for a safepoint.
boolean	printLocationInfo(Log log, org.graalvm.word.UnsignedWord value, boolean allowJavaHeapAccess, boolean allowUnsafeOperations) If the passed value is within the Java heap, this method prints some information about that value and returns true.
void	resumeAllocation()
void	suspendAllocation()
boolean	tearDown() Tear down the heap and release its memory.
static boolean	usesImageHeapCardMarking()
static boolean	usesImageHeapChunks()
void	waitForReferencePendingList() Blocks until the heap has pending references.
void	wakeUpReferencePendingListWaiters() Unblocks any threads in Heap.waitForReferencePendingList().
boolean	walkCollectedHeapObjects(ObjectVisitor visitor) Walk all heap objects except the native image heap objects.
boolean	walkImageHeapObjects(ObjectVisitor visitor) Walk all native image heap objects.
boolean	walkObjects(ObjectVisitor visitor) Walk all the objects in the heap.

Methods inherited from class com.oracle.svm.core.heap.Heap

getHeap, getLoadedClasses

Methods inherited from class java.lang.Object

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

Constructor Detail

HeapImpl

public HeapImpl(int pageSize)

Method Detail

getHeapImpl

public static HeapImpl getHeapImpl()

getImageHeapInfo

public static ImageHeapInfo getImageHeapInfo()

isInImageHeap

public boolean isInImageHeap(Object obj)

Description copied from class: Heap

Returns true if the given object is located in the image heap.

Specified by:

isInImageHeap in class Heap

isInImageHeap

public boolean isInImageHeap(org.graalvm.word.Pointer objPointer)

Description copied from class: Heap

Returns true if the object at the given address is located in the image heap. Depending on the used GC, this method may only work reliably for pointers that point to the start of an object.

Specified by:

isInImageHeap in class Heap

isInPrimaryImageHeap

public boolean isInPrimaryImageHeap(Object obj)

Description copied from class: Heap

Whether the object is in the primary image heap, as opposed to an auxiliary image heap.

Specified by:

isInPrimaryImageHeap in class Heap

isInPrimaryImageHeap

public boolean isInPrimaryImageHeap(org.graalvm.word.Pointer objPointer)

Description copied from class: Heap

Whether the object is in the primary image heap, as opposed to an auxiliary image heap.

Specified by:

isInPrimaryImageHeap in class Heap

suspendAllocation

public void suspendAllocation()

Specified by:

suspendAllocation in class Heap

resumeAllocation

public void resumeAllocation()

Specified by:

resumeAllocation in class Heap

walkObjects

public boolean walkObjects(ObjectVisitor visitor)

Description copied from class: Heap

Walk all the objects in the heap. Must only be executed as part of a VM operation that causes a safepoint.

Specified by:

walkObjects in class Heap

tearDown

public boolean tearDown()

Tear down the heap and release its memory.

Specified by:

tearDown in class Heap

getObjectHeader

public ObjectHeader getObjectHeader()

Description copied from class: Heap

Get the ObjectHeader implementation that this Heap uses. TODO: This is used during native image generation to put appropriate headers on Objects in the native image heap. Is there any reason to expose the whole ObjectHeader interface, since only setBootImageOnLong(0L) is used then, to get the native image object header bits? TODO: Would an "Unsigned getBootImageObjectHeaderBits()" method be sufficient?

Specified by:

getObjectHeader in class Heap

getGC

public GC getGC()

Specified by:

getGC in class Heap

getRuntimeCodeInfoGCSupport

public RuntimeCodeInfoGCSupport getRuntimeCodeInfoGCSupport()

Specified by:

getRuntimeCodeInfoGCSupport in class Heap

getAccounting

public HeapAccounting getAccounting()

isAllocationDisallowed

public boolean isAllocationDisallowed()

Specified by:

isAllocationDisallowed in class Heap

getYoungGeneration

public YoungGeneration getYoungGeneration()

getOldGeneration

public OldGeneration getOldGeneration()

getUsedBytes

public org.graalvm.word.UnsignedWord getUsedBytes()

getCommittedBytes

public org.graalvm.word.UnsignedWord getCommittedBytes()

getClassCount

public int getClassCount()

Description copied from class: Heap

Returns the number of classes in the heap (initialized as well as uninitialized).

Specified by:

getClassCount in class Heap

getAllClasses

protected List<Class<?>> getAllClasses()

Description copied from class: Heap

Get all known classes. Intentionally protected to prevent access to classes that have not been "loaded" yet, see PredefinedClassesSupport.

Specified by:

getAllClasses in class Heap

prepareForSafepoint

public void prepareForSafepoint()

Description copied from class: Heap

Prepare the heap for a safepoint.

Specified by:

prepareForSafepoint in class Heap

endSafepoint

public void endSafepoint()

Description copied from class: Heap

Reset the heap to the normal execution state.

Specified by:

endSafepoint in class Heap

attachThread

public void attachThread(org.graalvm.nativeimage.IsolateThread isolateThread)

Description copied from class: Heap

Notifies the heap that a new thread was attached to the VM. This allows to initialize heap-specific datastructures, e.g., the TLAB. This method is called for every thread except the main thread (i.e., the one that maps the image heap).

Specified by:

attachThread in class Heap

detachThread

public void detachThread(org.graalvm.nativeimage.IsolateThread isolateThread)

Description copied from class: Heap

Notifies the heap that a thread will be detached from the VM. This allows to cleanup heap-specific resources, e.g., the TLAB. This method is called for every thread except the main thread (i.e., the one that maps the image heap).

Specified by:

detachThread in class Heap

usesImageHeapChunks

public static boolean usesImageHeapChunks()

usesImageHeapCardMarking

public static boolean usesImageHeapCardMarking()

getPreferredAddressSpaceAlignment

public int getPreferredAddressSpaceAlignment()

Description copied from class: Heap

Returns a multiple to which the heap address space should be aligned to at runtime.

Specified by:

getPreferredAddressSpaceAlignment in class Heap

See Also:

CommittedMemoryProvider.guaranteesHeapPreferredAddressSpaceAlignment()

getImageHeapOffsetInAddressSpace

public int getImageHeapOffsetInAddressSpace()

Description copied from class: Heap

Returns an offset relative to the heap base, at which the image heap should be mapped into the address space.

Specified by:

getImageHeapOffsetInAddressSpace in class Heap

getImageHeapNullRegionSize

public int getImageHeapNullRegionSize()

Description copied from class: Heap

Returns the number of null bytes that should be prepended to the image heap during the image build. This value must be a multiple of the page size. When the image heap is mapped at runtime, this extra memory gets mapped as well but is marked as inaccessible (see ImageHeapProvider for more details).

Specified by:

getImageHeapNullRegionSize in class Heap

walkImageHeapObjects

public boolean walkImageHeapObjects(ObjectVisitor visitor)

Description copied from class: Heap

Walk all native image heap objects. Must only be executed as part of a VM operation that causes a safepoint.

Specified by:

walkImageHeapObjects in class Heap

walkCollectedHeapObjects

public boolean walkCollectedHeapObjects(ObjectVisitor visitor)

Description copied from class: Heap

Walk all heap objects except the native image heap objects. Must only be executed as part of a VM operation that causes a safepoint.

Specified by:

walkCollectedHeapObjects in class Heap

createBarrierSet

public org.graalvm.compiler.nodes.gc.BarrierSet createBarrierSet(jdk.vm.ci.meta.MetaAccessProvider metaAccess)

Description copied from class: Heap

Returns a suitable BarrierSet for the garbage collector that is used for this heap.

Specified by:

createBarrierSet in class Heap

hasReferencePendingList

public boolean hasReferencePendingList()

Description copied from class: Heap

Determines if the heap currently has Reference objects that are pending to be enqueued.

Specified by:

hasReferencePendingList in class Heap

waitForReferencePendingList

public void waitForReferencePendingList()
                                 throws InterruptedException

Description copied from class: Heap

Blocks until the heap has pending references.

Specified by:

waitForReferencePendingList in class Heap

Throws:

InterruptedException

wakeUpReferencePendingListWaiters

public void wakeUpReferencePendingListWaiters()

Description copied from class: Heap

Unblocks any threads in Heap.waitForReferencePendingList().

Specified by:

wakeUpReferencePendingListWaiters in class Heap

getAndClearReferencePendingList

public Reference<?> getAndClearReferencePendingList()

Description copied from class: Heap

Atomically get the list of pending references and clears (resets) it. May return null.

Specified by:

getAndClearReferencePendingList in class Heap

printLocationInfo

public boolean printLocationInfo(Log log,
                                 org.graalvm.word.UnsignedWord value,
                                 boolean allowJavaHeapAccess,
                                 boolean allowUnsafeOperations)

Description copied from class: Heap

If the passed value is within the Java heap, this method prints some information about that value and returns true. Otherwise, the method returns false.

Specified by:

printLocationInfo in class Heap

optionValueChanged

public void optionValueChanged(RuntimeOptionKey<?> key)

Description copied from class: Heap

Notify the GC that the value of a GC-relevant option changed.

Specified by:

optionValueChanged in class Heap