diff -r e92153ed8bdc -r 29b0d0b61615 src/hotspot/share/classfile/classLoaderDataGraph.inline.hpp
--- a/src/hotspot/share/classfile/classLoaderDataGraph.inline.hpp	Mon Nov 25 12:30:24 2019 +0100
+++ b/src/hotspot/share/classfile/classLoaderDataGraph.inline.hpp	Mon Nov 25 12:31:39 2019 +0100
@@ -50,7 +50,7 @@
 }
 
 void ClassLoaderDataGraph::inc_instance_classes(size_t count) {
-  Atomic::add(count, &_num_instance_classes);
+  Atomic::add(&_num_instance_classes, count);
 }
 
 void ClassLoaderDataGraph::dec_instance_classes(size_t count) {
@@ -59,7 +59,7 @@
 }
 
 void ClassLoaderDataGraph::inc_array_classes(size_t count) {
-  Atomic::add(count, &_num_array_classes);
+  Atomic::add(&_num_array_classes, count);
 }
 
 void ClassLoaderDataGraph::dec_array_classes(size_t count) {