Merge pull request #131 from bulasevich/GR-62942

[Backport] [Oracle GraalVM] [GR-62942] Backport to 23.1: java.lang.ref.Reference and its subclasses are not cloneable.

Author: zakkak

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/graal/jdk/SubstrateObjectCloneSnippets.java

@@ -68,6 +68,7 @@
 import com.oracle.svm.core.heap.PodReferenceMapDecoder;
 import com.oracle.svm.core.hub.DynamicHub;
 import com.oracle.svm.core.hub.DynamicHubSupport;
+import com.oracle.svm.core.hub.HubType;
 import com.oracle.svm.core.hub.LayoutEncoding;
 import com.oracle.svm.core.meta.SharedType;
 import com.oracle.svm.core.snippets.KnownIntrinsics;
@@ -90,14 +91,19 @@ public static void registerForeignCalls(SubstrateForeignCallsProvider foreignCal
     }
 
     @SubstrateForeignCallTarget(stubCallingConvention = false)
+    // @BasedOnJDKFile("https://github.com/openjdk/jdk/blob/jdk-21+35/src/hotspot/share/prims/jvm.cpp#L643-L692")
     private static Object doClone(Object original) throws CloneNotSupportedException, InstantiationException {
         if (original == null) {
             throw new NullPointerException();
         } else if (!(original instanceof Cloneable)) {
-            throw new CloneNotSupportedException("Object is no instance of Cloneable.");
+            throw new CloneNotSupportedException("Object is no instance of Cloneable: " + original.getClass().getName());
         }
 
         DynamicHub hub = KnownIntrinsics.readHub(original);
+        if (hub.getHubType() == HubType.REFERENCE_INSTANCE) {
+            throw new CloneNotSupportedException("Subclasses of java.lang.ref.Reference are not cloneable: " + hub.getName());
+        }
+
         int layoutEncoding = hub.getLayoutEncoding();
         boolean isArrayLike = LayoutEncoding.isArrayLike(layoutEncoding);