--- a/jvmci/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedObjectTypeImpl.java	Thu Mar 31 10:21:27 2016 -0700
+++ b/jvmci/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedObjectTypeImpl.java	Fri Apr 01 10:32:24 2016 -0700
@@ -169,6 +169,10 @@
 
     @Override
     public AssumptionResult<ResolvedJavaType> findLeafConcreteSubtype() {
+        if (isLeaf()) {
+            // No assumptions are required.
+            return new AssumptionResult<>(this);
+        }
         HotSpotVMConfig config = config();
         if (isArray()) {
             ResolvedJavaType elementalType = getElementalType();
@@ -206,8 +210,7 @@
                 }
                 return null;
             }
-
-            return new AssumptionResult<>(implementor, new LeafType(implementor), new ConcreteSubtype(this, implementor));
+            return concreteSubtype(implementor);
         } else {
             HotSpotResolvedObjectTypeImpl type = this;
             while (type.isAbstract()) {
@@ -221,7 +224,7 @@
                 return null;
             }
             if (this.isAbstract()) {
-                return new AssumptionResult<>(type, new LeafType(type), new ConcreteSubtype(this, type));
+                return concreteSubtype(type);
             } else {
                 assert this.equals(type);
                 return new AssumptionResult<>(type, new LeafType(type));
@@ -229,6 +232,14 @@
         }
     }
 
+    private AssumptionResult<ResolvedJavaType> concreteSubtype(HotSpotResolvedObjectTypeImpl type) {
+        if (type.isLeaf()) {
+            return new AssumptionResult<>(type, new ConcreteSubtype(this, type));
+        } else {
+            return new AssumptionResult<>(type, new LeafType(type), new ConcreteSubtype(this, type));
+        }
+    }
+
     /**
      * Returns if type {@code type} is a leaf class. This is the case if the
      * {@code Klass::_subklass} field of the underlying class is zero.