The attached Java Fuzzer test crashes with the following assertion:

To reproduce:
$ java -XX:+VerifyStack Test.java
$ java -XX:+VerifyStack Reduced.java

#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/opt/mach5/mesos/work_dir/slaves/3c846bae-ce30-4a97-93ee-9fef4497ccb6-S124123/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/57294efe-464f-4c0a-b55a-fd67bfa32e7b/runs/71c23d41-87fd-4de4-92b5-4ba130c3e1dd/workspace/open/src/hotspot/share/oops/generateOopMap.cpp:2216), pid=2766569, tid=2766570
# assert(bb->is_reachable()) failed: getting result from unreachable basicblock
#
# JRE version: Java(TM) SE Runtime Environment (18.0+7) (fastdebug build 18-ea+7-268)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 18-ea+7-268, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0xd349cc] GenerateOopMap::result_for_basicblock(int)+0x9c
..........
Command Line: -XX:CompileCommand=quiet -XX:CompileCommand=dontinline,Test::* -XX:+VerifyOops -XX:+VerifyStack -XX:+VerifyLastFrame -XX:+VerifyBeforeGC -XX:+VerifyAfterGC -XX:+VerifyDuringGC -XX:+VerifyAdapterSharing Test
..........
Current thread (0x00007f5934029370): JavaThread "main" [_thread_in_Java, id=2766570, stack(0x00007f593d827000,0x00007f593d928000)]

Stack: [0x00007f593d827000,0x00007f593d928000], sp=0x00007f593d9242c0, free space=1012k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0xd349cc] GenerateOopMap::result_for_basicblock(int)+0x9c
V [libjvm.so+0x1530e2e] OopMapForCacheEntry::compute_map(Thread*)+0x17e
V [libjvm.so+0x1532ad1] OopMapCacheEntry::fill(methodHandle const&, int)+0xf1
V [libjvm.so+0x15333c3] OopMapCache::compute_one_oop_map(methodHandle const&, int, InterpreterOopMap*)+0x63
V [libjvm.so+0xa9edcc] Deoptimization::unpack_frames(JavaThread*, int)+0xaec
v ~DeoptimizationBlob
j Test.iMeth(II)I+346
j Test.vMeth1(II)V+86
j Test.vMeth(IJJ)V+119
j Test.mainTest([Ljava/lang/String;)V+72
j Test.main([Ljava/lang/String;)V+18
v ~StubRoutines::call_stub
V [libjvm.so+0xe5f8f4] JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, JavaThread*)+0x504
V [libjvm.so+0xf91c95] jni_invoke_static(JNIEnv_*, JavaValue*, _jobject*, JNICallType, _jmethodID*, JNI_ArgumentPusher*, JavaThread*) [clone .constprop.1]+0x375
V [libjvm.so+0xf953a5] jni_CallStaticVoidMethod+0x1c5
C [libjli.so+0x47e7] JavaMain+0xd37
C [libjli.so+0x7d19] ThreadJavaMain+0x9

Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
v ~DeoptimizationBlob
j Test.iMeth(II)I+346
j Test.vMeth1(II)V+86
j Test.vMeth(IJJ)V+119
j Test.mainTest([Ljava/lang/String;)V+72
j Test.main([Ljava/lang/String;)V+18
v ~StubRoutines::call_stub