--- old/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/graphbuilderconf/NodePlugin.java	2019-03-12 08:09:57.131712913 +0100
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/graphbuilderconf/NodePlugin.java	2019-03-12 08:09:56.775710606 +0100
@@ -221,6 +221,9 @@
      * nodes) and fixed nodes must be manually {@linkplain FixedWithNextNode#setNext added} as
      * successors of {@code afterExceptionLoaded}.
      *
+     * The reason for this constraint is that when this plugin runs, it's inserting instructions
+     * into a different block than the one currently being parsed.
+     *
      * @param graph the graph being parsed
      * @param afterExceptionLoaded the last fixed node after loading the exception
      * @return the last fixed node after instrumentation