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package com.oracle.svm.core.genscavenge;
import com.oracle.svm.core.config.ConfigurationValues;
import com.oracle.svm.core.genscavenge.AbstractImageHeapLayouter.AbstractImageHeapPartition;
import com.oracle.svm.core.image.ImageHeapObject;
An unstructured image heap partition that just contains a linear sequence of image heap objects.
/**
* An unstructured image heap partition that just contains a linear sequence of image heap objects.
*/
public class LinearImageHeapPartition extends AbstractImageHeapPartition {
Object firstObject;
Object lastObject;
long startOffset = -1;
long endOffset = -1;
LinearImageHeapPartition(String name, boolean writable) {
super(name, writable);
}
void allocateObjects(LinearImageHeapAllocator allocator) {
allocator.align(getStartAlignment());
startOffset = allocator.getPosition();
for (ImageHeapObject info : getObjects()) {
allocate(info, allocator);
}
allocator.align(getEndAlignment());
endOffset = allocator.getPosition();
}
private void allocate(ImageHeapObject info, LinearImageHeapAllocator allocator) {
assert info.getPartition() == this;
if (firstObject == null) {
firstObject = info.getObject();
}
long offsetInPartition = allocator.allocate(info.getSize()) - startOffset;
assert ConfigurationValues.getObjectLayout().isAligned(offsetInPartition) : "start: " + offsetInPartition + " must be aligned.";
info.setOffsetInPartition(offsetInPartition);
lastObject = info.getObject();
}
@Override
public void assign(ImageHeapObject obj) {
assert startOffset == -1 && endOffset == -1 : "Adding objects late is not supported";
super.assign(obj);
}
@Override
public long getStartOffset() {
assert startOffset >= 0 : "Start offset not yet set";
return startOffset;
}
public long getEndOffset() {
assert endOffset >= 0 : "End offset not yet set";
return endOffset;
}
@Override
public long getSize() {
return getEndOffset() - getStartOffset();
}
}