--- old/src/hotspot/cpu/aarch64/stubGenerator_aarch64.cpp	2019-05-03 12:32:02.352354250 +0200
+++ new/src/hotspot/cpu/aarch64/stubGenerator_aarch64.cpp	2019-05-03 12:32:02.158351534 +0200
@@ -1788,6 +1788,8 @@
     }
 #endif //ASSERT
 
+    // Note: checkcast arraycopy is always disjoint. If it were not, then we wouldn't
+    // need to checkcast.
     DecoratorSet decorators = IN_HEAP | IS_ARRAY | ARRAYCOPY_CHECKCAST | ARRAYCOPY_DISJOINT;
     bool is_oop = true;
     if (dest_uninitialized) {