In JDK13, test test/hotspot/jtreg/gc/shenandoah/compiler/TestWriteBarrierClearControl.java

uses C2 tuning options - StressLCM and StressGCM.
but these options aren't available on 32-bit clientVM (win32) hence test fails with Unrecognized vm option.

probably need to add -server to otherVM options

Update: another test is

test/hotspot/jtreg/gc/shenandoah/options/TestLoopMiningArguments.java

which uses UseCountedLoopSafepoints