Merge pull request #21505 from amicic/prepare_isdataadjacent_early

Prepare and store is-data-adjacent early

Author: dmitripivkine

runtime/gc_base/IndexableObjectAllocationModel.cpp

@@ -73,7 +73,7 @@ MM_IndexableObjectAllocationModel::initializeAllocateDescription(MM_EnvironmentB
 
 	case GC_ArrayletObjectModel::InlineContiguous:
 		/* Check if we're dealing with a camouflaged discontiguous array - these arrays will require slow-path allocate */
-		if (isVirtualLargeObjectHeapEnabled && (!extensions->indexableObjectModel.shouldDataBeAdjacentToHeader(_dataSize))) {
+		if (isVirtualLargeObjectHeapEnabled && (!_isDataAdjacent)) {
 			if (isGCAllowed()) {
 				layoutSizeInBytes = _dataSize;
 				setAllocatable(true);
@@ -145,7 +145,6 @@ MM_IndexableObjectAllocationModel::initializeIndexableObject(MM_EnvironmentBase
 	GC_ArrayObjectModel *indexableObjectModel = &extensions->indexableObjectModel;
 	J9IndexableObject *spine = (J9IndexableObject*)initializeJavaObject(env, allocatedBytes);
 	_allocateDescription.setSpine(spine);
-	bool shouldDataBeAdjacentToHeader = false;
 	bool isVirtualLargeObjectHeapEnabled = indexableObjectModel->isVirtualLargeObjectHeapEnabled();
 
 	if (NULL != spine) {
@@ -163,8 +162,7 @@ MM_IndexableObjectAllocationModel::initializeIndexableObject(MM_EnvironmentBase
 			indexableObjectModel->setSizeInElementsForContiguous(spine, _numberOfIndexedFields);
 #if defined(J9VM_ENV_DATA64)
 			if (((J9JavaVM *)env->getLanguageVM())->isIndexableDataAddrPresent) {
-				shouldDataBeAdjacentToHeader = indexableObjectModel->shouldDataBeAdjacentToHeader(spine);
-				if (shouldDataBeAdjacentToHeader) {
+				if (_isDataAdjacent) {
 					indexableObjectModel->setDataAddrForContiguous(spine);
 				} else {
 					/* Set NULL temporarily to avoid possible complication with GC occurring while the object is partially initialized. */
@@ -179,15 +177,15 @@ MM_IndexableObjectAllocationModel::initializeIndexableObject(MM_EnvironmentBase
 	switch (_layout) {
 	case GC_ArrayletObjectModel::InlineContiguous:
 #if defined(J9VM_GC_SPARSE_HEAP_ALLOCATION)
-		if (isVirtualLargeObjectHeapEnabled && !shouldDataBeAdjacentToHeader) {
+		if (isVirtualLargeObjectHeapEnabled && !_isDataAdjacent) {
 			/* We still need to create leaves for discontiguous arrays that will be allocated at off-heap. */
 			spine = getSparseAddressAndDecommitLeaves(env, spine);
 			if (NULL != spine) {
 				Assert_MM_true(1 <= _numberOfArraylets);
 			}
 		}
 #endif /* defined (J9VM_GC_SPARSE_HEAP_ALLOCATION) */
-		if (!isVirtualLargeObjectHeapEnabled || shouldDataBeAdjacentToHeader) {
+		if (!isVirtualLargeObjectHeapEnabled || _isDataAdjacent) {
 			Assert_MM_true(1 == _numberOfArraylets);
 		}
 		break;

runtime/gc_base/IndexableObjectAllocationModel.hpp

@@ -48,6 +48,7 @@ class MM_IndexableObjectAllocationModel : public MM_JavaObjectAllocationModel
 	const uint32_t _numberOfIndexedFields;
 	const uintptr_t _dataSize;
 	const GC_ArrayletObjectModel::ArrayLayout _layout;
+	const bool _isDataAdjacent;
 	const bool _alignSpineDataSection;
 	const uintptr_t _numberOfArraylets;
 
@@ -110,6 +111,7 @@ class MM_IndexableObjectAllocationModel : public MM_JavaObjectAllocationModel
 		, _dataSize(env->getExtensions()->indexableObjectModel.getDataSizeInBytes(_class, _numberOfIndexedFields))
 		, _layout(env->getExtensions()->indexableObjectModel.getArrayletLayout(_class, _numberOfIndexedFields,
 				_allocateDescription.getMemorySpace()->getDefaultMemorySubSpace()->largestDesirableArraySpine()))
+		, _isDataAdjacent(env->getExtensions()->indexableObjectModel.shouldDataBeAdjacentToHeader(_dataSize))
 		, _alignSpineDataSection(env->getExtensions()->indexableObjectModel.shouldAlignSpineDataSection(_class))
 		, _numberOfArraylets(env->getExtensions()->indexableObjectModel.numArraylets(_dataSize))
 	{