com.oracle.svm.core.image

Interface ImageHeapLayouter

All Known Implementing Classes:

AbstractImageHeapLayouter, ChunkedImageHeapLayouter, LinearImageHeapLayouter

public interface ImageHeapLayouter

This class is responsible for computing and storing the layout of the native image heap. A native image heap consist of multiple ImageHeapPartitions. Every object in the native image heap is assigned to a position within a ImageHeapPartition.

Method Summary

Modifier and Type	Method and Description
void	assignObjectToPartition(ImageHeapObject info, boolean immutable, boolean references, boolean relocatable) Assign an object to the most suitable partition.
ImageHeapPartition[]	getPartitions() Returns all native image heap partitions.
ImageHeapLayoutInfo	layout(ImageHeap imageHeap, int pageSize) This method places all heap partitions as one contiguous memory block in one section.
void	writeMetadata(ByteBuffer imageHeapBytes, long imageHeapOffsetInBuffer) Based on the layout decided during an earlier call to ImageHeapLayouter.layout(com.oracle.svm.core.image.ImageHeap, int), fill the image heap in the supplied buffer with additional data structures, if any.

Method Detail

getPartitions

ImageHeapPartition[] getPartitions()

Returns all native image heap partitions.

assignObjectToPartition

void assignObjectToPartition(ImageHeapObject info,
                             boolean immutable,
                             boolean references,
                             boolean relocatable)

Assign an object to the most suitable partition.

layout

ImageHeapLayoutInfo layout(ImageHeap imageHeap,
                           int pageSize)

This method places all heap partitions as one contiguous memory block in one section. After calling that method, all native image heap objects are assigned their final address. This address must not change anymore.

writeMetadata

void writeMetadata(ByteBuffer imageHeapBytes,
                   long imageHeapOffsetInBuffer)

Based on the layout decided during an earlier call to ImageHeapLayouter.layout(com.oracle.svm.core.image.ImageHeap, int), fill the image heap in the supplied buffer with additional data structures, if any. At this time, the buffer already contains the laid out objects, which are not meant to be modified in this step.

Parameters:

imageHeapOffsetInBuffer - The offset of the first byte of the laid out image heap in the buffer. If a layouter subclass can be instructed to start laying out the image heap at a specific non-zero offset, and the image heap is intended to start at the same offset in the given buffer, the same offset must be specified to this method.