--- old/src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp	2020-04-03 22:13:09.358231836 +0200
+++ new/src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp	2020-04-03 22:13:09.250232554 +0200
@@ -67,6 +67,7 @@
           "GC mode to use.  Among other things, this defines which "        \
           "barriers are in in use. Possible values are:"                    \
           " normal - default concurrent GC (three pass mark-evac-update);"  \
+          " iu - incremental-update concurrent GC (three pass mark-evac-update);"  \
           " passive - stop the world GC only (either degenerated or full)") \
                                                                             \
   experimental(ccstr, ShenandoahGCHeuristics, "adaptive",                   \