--- old/src/hotspot/share/opto/parseHelper.cpp	2020-02-12 15:20:00.771482832 +0100
+++ new/src/hotspot/share/opto/parseHelper.cpp	2020-02-12 15:20:00.339482838 +0100
@@ -219,8 +219,9 @@
           extak = TypeKlassPtr::make(array_type);
         }
       }
-    } else if (!too_many_traps(Deoptimization::Reason_class_check) && tak != TypeKlassPtr::OBJECT) {
+    } else if (!too_many_traps(Deoptimization::Reason_array_check) && tak != TypeKlassPtr::OBJECT) {
       extak = tak->cast_to_exactness(true)->is_klassptr();
+      reason = Deoptimization::Reason_array_check;
     }
     if (extak != NULL) {
       always_see_exact_class = true;