While working on JDK-8056071 I added verification code to the AdvancedThresholdPolicy to check that all transitions are meaningful, i.e. no transition
- to the same level
- from level 1 and 4
- from level 3 to 2

The current implementation violates this assertion:

# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/opt/jprt/T/P1/091408.tohartma/s/hotspot/src/share/vm/runtime/advancedThresholdPolicy.cpp:221), pid=13436, tid=47676587804416
# assert(comp_level != max_task->comp_level() && comp_level != CompLevel_simple && comp_level != CompLevel_full_optimization && !(comp_level == CompLevel_full_profile && max_task->comp_level() == CompLevel_limited_profile)) failed: Bad transition of 'com.sun.tools.javac.code.Types.isSubtypeUncheckedInternal(Lcom/sun/tools/javac/code/Type;Lcom/sun/tools/javac/code/Type;Lcom/sun/tools/javac/util/Warner;)Z' from 2 to 2
#
# JRE version: Java(TM) SE Runtime Environment (9.0) (build 1.9.0-internal-fastdebug-201411050914.tohartma.8056071-b00)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (1.9.0-internal-fastdebug-201411050914.tohartma.8056071-b00 mixed mode linux-amd64 compressed oops)
# Core dump written. Default location: /opt/jprt/T/P1/091408.tohartma/s/hotspot/build/linux-x86_64/testoutput/JTwork/compiler/7119644/TestIntDoubleVect/core or core.13436
#
# An error report file with more information is saved as:
# /opt/jprt/T/P1/091408.tohartma/s/hotspot/build/linux-x86_64/testoutput/JTwork/compiler/7119644/TestIntDoubleVect/hs_err_pid13436.log
#
# If you would like to submit a bug report, please visit:
# http://bugreport.sun.com/bugreport/crash.jsp
#