When running with ubsan enabled test binaries, the following error has been observed :
Test gc/logging/TestGCId.jtr :

 stderr: [/jdk/src/hotspot/share/gc/shenandoah/heuristics/shenandoahAdaptiveHeuristics.cpp:245:44: runtime error: division by zero
    #0 0x7fff88638d6c in ShenandoahAdaptiveHeuristics::should_start_gc() (/build/images/jdk/lib/server/libjvm.so+0x7998d6c)
    #1 0x7fff88703d58 in ShenandoahControlThread::run_service() (/build/images/jdk/lib/server/libjvm.so+0x7a63d58)
    #2 0x7fff8628b730 in ConcurrentGCThread::run() (/build/images/jdk/lib/server/libjvm.so+0x55eb730)
    #3 0x7fff88cd9208 in Thread::call_run() (/build/images/jdk/lib/server/libjvm.so+0x8039208)
    #4 0x7fff880e6928 in thread_native_entry(Thread*) (/build/images/jdk/lib/server/libjvm.so+0x7446928)
    #5 0x7fff8dd79714 in start_thread (/lib64/libpthread.so.0+0x9714)
    #6 0x7fff8d12b774 in __GI___clone (/lib64/libc.so.6+0x13b774)

Looks like avg_alloc_rate can sometimes be zero, and we do not handle this at the moment :

  double avg_alloc_rate = _allocation_rate.upper_bound(_margin_of_error_sd);
  if (avg_cycle_time > allocation_headroom / avg_alloc_rate) {

Maybe we should simply test for if (avg_alloc_rate != 0,0f && ... ) additionally ?