Merge pull request #20139 from theresa-m/nr_array_2

Always create nullable array before null-restricted
eclipse-openj9 · Sep 11, 2024 · dc9157d · dc9157d
2 parents cf5af08 + ff1d09b
commit dc9157d
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Showing 3 changed files with 35 additions and 21 deletions.
diff --git a/runtime/oti/j9.h b/runtime/oti/j9.h
@@ -362,6 +362,7 @@ static const struct { \
 #define J9_IS_NULL_RESTRICTED_FIELD_FLATTENED(fieldClazz, romFieldShape) FALSE
 #define J9_VALUETYPE_FLATTENED_SIZE(clazz)((UDATA) 0) /* It is not possible for this macro to be used since we always check J9_IS_J9CLASS_FLATTENED before ever using it. */
 #define J9_IS_J9ARRAYCLASS_NULL_RESTRICTED(clazz) FALSE
+#define J9CLASS_GET_NULLRESTRICTED_ARRAY(clazz) NULL
 #endif /* defined(J9VM_OPT_VALHALLA_FLATTENABLE_VALUE_TYPES) */
 #define IS_REF_OR_VAL_SIGNATURE(firstChar) ('L' == (firstChar))
 

diff --git a/runtime/vm/classsupport.c b/runtime/vm/classsupport.c
@@ -188,20 +188,8 @@ findPrimitiveArrayClass(J9JavaVM* vm, jchar sigChar)
 	}
 }
 
-
-/**
- * @internal
- *
- * Allocates and fills in the relevant fields of an array class
- */
-J9Class *
-internalCreateArrayClass(J9VMThread *vmThread, J9ROMArrayClass *romClass, J9Class *elementClass)
-{
-	return internalCreateArrayClassWithOptions(vmThread, romClass, elementClass, 0);
-}
-
-J9Class *
-internalCreateArrayClassWithOptions(J9VMThread *vmThread, J9ROMArrayClass *romClass, J9Class *elementClass, UDATA options)
+static J9Class *
+internalCreateArrayClassHelper(J9VMThread *vmThread, J9ROMArrayClass *romClass, J9Class *elementClass, UDATA options)
 {
 	J9Class *result = NULL;
 	j9object_t heapClass = J9VM_J9CLASS_TO_HEAPCLASS(elementClass);
@@ -217,8 +205,12 @@ internalCreateArrayClassWithOptions(J9VMThread *vmThread, J9ROMArrayClass *romCl
 	 * creating an instance of the array. Element class init must be done
 	 * before the arrayClass is created so that in the case of an init failure
 	 * the arrayClass is not temporarily exposed.
+	 * Don't try to initialize class for null-restricted array creation since
+	 * the regular arrayClass will always be created first.
 	 */
-	if (J9_IS_J9CLASS_ALLOW_DEFAULT_VALUE(elementClass)) {
+	if (J9_IS_J9CLASS_ALLOW_DEFAULT_VALUE(elementClass)
+		&& J9_ARE_NO_BITS_SET(options, J9_FINDCLASS_FLAG_CLASS_OPTION_NULL_RESTRICTED_ARRAY)
+	) {
 		UDATA initStatus = elementClass->initializeStatus;
 		if ((J9ClassInitSucceeded != initStatus) && ((UDATA)vmThread != initStatus)) {
 			initializeClass(vmThread, elementClass);
@@ -267,6 +259,31 @@ internalCreateArrayClassWithOptions(J9VMThread *vmThread, J9ROMArrayClass *romCl
 	return result;
 }
 
+/**
+ * @internal
+ *
+ * Allocates and fills in the relevant fields of an array class
+ */
+J9Class *
+internalCreateArrayClass(J9VMThread *vmThread, J9ROMArrayClass *romClass, J9Class *elementClass)
+{
+	return internalCreateArrayClassHelper(vmThread, romClass, elementClass, 0);
+}
+
+J9Class *
+internalCreateArrayClassWithOptions(J9VMThread *vmThread, J9ROMArrayClass *romClass, J9Class *elementClass, UDATA options)
+{
+	/* Create elementClass's arrayClass as a prerequisite to nullRestrictedArrayClass */
+	if (J9_ARE_ALL_BITS_SET(options, J9_FINDCLASS_FLAG_CLASS_OPTION_NULL_RESTRICTED_ARRAY)
+		&& (NULL == elementClass->arrayClass)
+	) {
+		if (NULL == internalCreateArrayClassHelper(vmThread, romClass, elementClass, 0)) {
+			return NULL;
+		}
+	}
+	return internalCreateArrayClassHelper(vmThread, romClass, elementClass, options);
+}
+
 /**
  * Peek the classHashTable to see if the `className` class has already been loaded by `classLoader`.
  *

diff --git a/runtime/vm/createramclass.cpp b/runtime/vm/createramclass.cpp
@@ -2404,18 +2404,14 @@ internalCreateRAMClassDone(J9VMThread *vmThread, J9ClassLoader *classLoader, J9C
 			if (J9ROMCLASS_IS_ARRAY(romClass)) {
 #if defined(J9VM_OPT_VALHALLA_FLATTENABLE_VALUE_TYPES)
 				if (J9_ARE_ALL_BITS_SET(options, J9_FINDCLASS_FLAG_CLASS_OPTION_NULL_RESTRICTED_ARRAY)) {
+					((J9ArrayClass *)state->ramClass)->companionArray = elementClass->arrayClass;
 					elementClass->nullRestrictedArrayClass = state->ramClass;
+					((J9ArrayClass *)elementClass->arrayClass)->companionArray = elementClass->nullRestrictedArrayClass;
 				} else
 #endif /* defined(J9VM_OPT_VALHALLA_FLATTENABLE_VALUE_TYPES) */
 				{
 					((J9ArrayClass *)elementClass)->arrayClass = state->ramClass;
 				}
-#if defined(J9VM_OPT_VALHALLA_FLATTENABLE_VALUE_TYPES)
-				if ((NULL != elementClass->nullRestrictedArrayClass) && (NULL != elementClass->arrayClass)) {
-					((J9ArrayClass *)elementClass->arrayClass)->companionArray = elementClass->nullRestrictedArrayClass;
-					((J9ArrayClass *)elementClass->nullRestrictedArrayClass)->companionArray = elementClass->arrayClass;
-				}
-#endif /* defined(J9VM_OPT_VALHALLA_FLATTENABLE_VALUE_TYPES) */
 				/* Assigning into the arrayClass field creates an implicit reference to the class from its class loader */
 				javaVM->memoryManagerFunctions->j9gc_objaccess_postStoreClassToClassLoader(vmThread, classLoader, state->ramClass);
 			}