Test crashed with 

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error (open/src/hotspot/share/opto/phaseX.cpp:897), pid=12368, tid=12379
#  assert(d->is_CFG() && n->is_CFG()) failed: must have CFG nodes
#
# JRE version: Java(TM) SE Runtime Environment (14.0+21) (fastdebug build 14-ea+21-927)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 14-ea+21-927, compiled mode, sharing, compressed oops, g1 gc, linux-amd64)
# Problematic frame:
# V  [libjvm.so+0x14bf6e4]  PhaseGVN::is_dominator_helper(Node*, Node*, bool) [clone .part.143]+0x94
#
# Core dump will be written. Default location: Core dumps may be processed with "/usr/libexec/abrt-hook-ccpp %s %c %p %u %g %t e %P %I %h" (or dumping to /tmp/fuzzer.tmp.dKU4CHGepZ/core.12368)
#
# If you would like to submit a bug report, please visit:
#   https://bugreport.java.com/bugreport/crash.jsp
#

---------------  S U M M A R Y ------------

Command Line: -Xmx1G -Xcomp -Xbatch -XX:-TieredCompilation -XX:CompileOnly=Test Test

Host: Intel(R) Xeon(R) CPU E5-2690 0 @ 2.90GHz, 4 cores, 14G, Oracle Linux Server release 7.5
Time: Mon Nov  4 20:50:16 2019 UTC elapsed time: 0 seconds (0d 0h 0m 0s)

---------------  T H R E A D  ---------------

Current thread (0x00007fc224256800):  JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=12379, stack(0x00007fc214b47000,0x00007fc214c48000)]


Current CompileTask:
C2:    487   67   !b        Test::mainTest (821 bytes)

Stack: [0x00007fc214b47000,0x00007fc214c48000],  sp=0x00007fc214c433f0,  free space=1008k
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [libjvm.so+0x14bf6e4]  PhaseGVN::is_dominator_helper(Node*, Node*, bool) [clone .part.143]+0x94
V  [libjvm.so+0x85db1f]  ConstraintCastNode::dominating_cast(PhaseGVN*, PhaseTransform*) const+0x25f
V  [libjvm.so+0x85e19b]  ConstraintCastNode::Identity(PhaseGVN*)+0x1b
V  [libjvm.so+0x14cc9ef]  PhaseIterGVN::transform_old(Node*)+0x36f
V  [libjvm.so+0x14cd35d]  PhaseIterGVN::optimize()+0x5d
V  [libjvm.so+0x9d6af6]  Compile::Optimize()+0x566
V  [libjvm.so+0x9d8634]  Compile::Compile(ciEnv*, C2Compiler*, ciMethod*, int, bool, bool, bool, DirectiveSet*)+0x1094
V  [libjvm.so+0x81ed30]  C2Compiler::compile_method(ciEnv*, ciMethod*, int, DirectiveSet*)+0x110
V  [libjvm.so+0x9e4ebc]  CompileBroker::invoke_compiler_on_method(CompileTask*)+0x2cc
V  [libjvm.so+0x9e5e68]  CompileBroker::compiler_thread_loop()+0x468
V  [libjvm.so+0x170e3e6]  JavaThread::thread_main_inner()+0x226
V  [libjvm.so+0x1713af6]  Thread::call_run()+0xf6
V  [libjvm.so+0x1434b5e]  thread_native_entry(Thread*)+0x10e

Register to memory mapping:

RAX=0x00007fc22e1fe000 points into unknown readable memory: 58 00 00 00 00 00 00 00
RBX=0x00007fc1e813e788 points into unknown readable memory: a0 1f 4c 2d c2 7f 00 00
RCX=0x00007fc22d16bfbe: <offset 0x0000000001a77fbe> in /scratch/lmesnik/jenkins/workspace/JavaFuzzer/jdk-14/fastdebug/lib/server/libjvm.so at 0x00007fc22b6f4000
RDX=0x00007fc22d0b6198: <offset 0x00000000019c2198> in /scratch/lmesnik/jenkins/workspace/JavaFuzzer/jdk-14/fastdebug/lib/server/libjvm.so at 0x00007fc22b6f4000
RSP=0x00007fc214c433f0 is pointing into the stack for thread: 0x00007fc224256800
RBP=0x00007fc214c43410 is pointing into the stack for thread: 0x00007fc224256800
RSI=0x0000000000000381 is an unknown value
RDI=0x00007fc22d0df528: <offset 0x00000000019eb528> in /scratch/lmesnik/jenkins/workspace/JavaFuzzer/jdk-14/fastdebug/lib/server/libjvm.so at 0x00007fc22b6f4000
R8 =0x0000000000000001 is an unknown value
R9 =0x0000000000000001 is an unknown value
R10=0x00007fc22cbc1d80: <offset 0x00000000014cdd80> in /scratch/lmesnik/jenkins/workspace/JavaFuzzer/jdk-14/fastdebug/lib/server/libjvm.so at 0x00007fc22b6f4000
R11=0x0 is NULL
R12=0x00007fc214c43480 is pointing into the stack for thread: 0x00007fc224256800
R13=0x00007fc1e876a9c8 points into unknown readable memory: 60 85 4e 2d c2 7f 00 00
R14=0x0 is NULL
R15=0x00007fc1e876a710 points into unknown readable memory: 80 69 4b 2d c2 7f 00 00


Registers:
RAX=0x00007fc22e1fe000, RBX=0x00007fc1e813e788, RCX=0x00007fc22d16bfbe, RDX=0x00007fc22d0b6198
RSP=0x00007fc214c433f0, RBP=0x00007fc214c43410, RSI=0x0000000000000381, RDI=0x00007fc22d0df528
R8 =0x0000000000000001, R9 =0x0000000000000001, R10=0x00007fc22cbc1d80, R11=0x0000000000000000
R12=0x00007fc214c43480, R13=0x00007fc1e876a9c8, R14=0x0000000000000000, R15=0x00007fc1e876a710
RIP=0x00007fc22cbb36e4, EFLAGS=0x0000000000010246, CSGSFS=0x0000000000000033, ERR=0x0000000000000006
  TRAPNO=0x000000000000000e

Top of Stack: (sp=0x00007fc214c433f0)
0x00007fc214c433f0:   00007fc1e8558050 00007fc214c43480
0x00007fc214c43400:   00007fc1e802fe98 00007fc214c43450
0x00007fc214c43410:   00007fc214c434e0 00007fc22bf51b1f
0x00007fc214c43420:   00007fc1e813e788 00007fc214c437a0 

Instructions: (pc=0x00007fc22cbb36e4)
0x00007fc22cbb35e4:   41 00 be 37 03 00 00 48 8d 3d 56 36 41 00 48 8b
0x00007fc22cbb35f4:   00 48 89 e5 c6 00 58 31 c0 e8 fe 69 5d ff 5d e9
0x00007fc22cbb3604:   68 ce f6 ff 0f 1f 84 00 00 00 00 00 48 8d 05 09
0x00007fc22cbb3614:   5d 94 00 55 48 8d 0d 31 bf 52 00 48 8d 15 52 bf
0x00007fc22cbb3624:   52 00 be 64 01 00 00 48 8d 3d 96 7d 41 00 48 8b
0x00007fc22cbb3634:   00 48 89 e5 c6 00 58 31 c0 e8 be 69 5d ff 5d e9
0x00007fc22cbb3644:   28 ce f6 ff 0f 1f 84 00 00 00 00 00 55 48 89 e5
0x00007fc22cbb3654:   41 56 41 89 d6 41 55 49 89 fd 41 54 53 48 8b 07
0x00007fc22cbb3664:   48 89 f3 ff 50 10 84 c0 74 52 48 8b 03 48 89 df
0x00007fc22cbb3674:   ff 50 10 84 c0 74 45 45 0f b6 f6 45 31 e4 eb 21
0x00007fc22cbb3684:   0f 1f 40 00 48 89 df 44 89 f6 41 83 c4 01 e8 69
0x00007fc22cbb3694:   5f 8f ff 48 89 c3 48 85 c0 74 59 41 83 fc 63 7f
0x00007fc22cbb36a4:   53 49 39 dd 75 de 5b b8 01 00 00 00 41 5c 41 5d
0x00007fc22cbb36b4:   41 5e 5d c3 0f 1f 84 00 00 00 00 00 48 8d 05 59
0x00007fc22cbb36c4:   5c 94 00 48 8d 0d f0 88 5b 00 48 8d 15 c3 2a 50
0x00007fc22cbb36d4:   00 be 81 03 00 00 48 8d 3d 47 be 52 00 48 8b 00
0x00007fc22cbb36e4:   c6 00 58 31 c0 e8 12 69 5d ff e8 7d cd f6 ff eb
0x00007fc22cbb36f4:   86 0f 1f 00 5b 31 c0 41 5c 41 5d 41 5e 5d c3 90
0x00007fc22cbb3704:   66 66 2e 0f 1f 84 00 00 00 00 00 90 48 8b 0e 48
0x00007fc22cbb3714:   8d 3d 76 e5 00 00 48 89 f0 48 8b 49 20 48 39 f9
0x00007fc22cbb3724:   75 0a c3 66 0f 1f 84 00 00 00 00 00 48 89 d6 48
0x00007fc22cbb3734:   89 c7 ff e1 0f 1f 84 00 00 00 00 00 55 48 89 e5
0x00007fc22cbb3744:   41 54 53 48 89 f3 48 89 d6 48 8d 15 2c e5 00 00
0x00007fc22cbb3754:   48 8b 03 48 8b 40 18 48 39 d0 75 10 48 89 d8 5b
0x00007fc22cbb3764:   41 5c 5d c3 0f 1f 84 00 00 00 00 00 49 89 cc 48
0x00007fc22cbb3774:   89 ca 48 89 df ff d0 48 39 c3 74 e0 48 8b 10 5b
0x00007fc22cbb3784:   4c 89 e6 48 89 c7 41 5c 5d 48 8b 4a 10 31 d2 ff
0x00007fc22cbb3794:   e1 90 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5
0x00007fc22cbb37a4:   53 48 89 fb 48 83 ec 08 85 f6 74 10 48 8b 03 48
0x00007fc22cbb37b4:   8b 00 48 83 c4 08 5b 5d c3 0f 1f 00 48 8d 05 59
0x00007fc22cbb37c4:   5b 94 00 48 8d 0d 99 e7 57 00 48 8d 15 60 0c 58
0x00007fc22cbb37d4:   00 be 78 01 00 00 48 8d 3d e7 57 41 00 48 8b 00 


Stack slot to memory mapping:
stack at sp + 0 slots: 0x00007fc1e8558050 points into unknown readable memory: 80 69 4b 2d c2 7f 00 00
stack at sp + 1 slots: 0x00007fc214c43480 is pointing into the stack for thread: 0x00007fc224256800
stack at sp + 2 slots: 0x00007fc1e802fe98 points into unknown readable memory: a0 6b 4b 2d c2 7f 00 00
stack at sp + 3 slots: 0x00007fc214c43450 is pointing into the stack for thread: 0x00007fc224256800
stack at sp + 4 slots: 0x00007fc214c434e0 is pointing into the stack for thread: 0x00007fc224256800
stack at sp + 5 slots: 0x00007fc22bf51b1f: <offset 0x000000000085db1f> in /scratch/lmesnik/jenkins/workspace/JavaFuzzer/jdk-14/fastdebug/lib/server/libjvm.so at 0x00007fc22b6f4000
stack at sp + 6 slots: 0x00007fc1e813e788 points into unknown readable memory: a0 1f 4c 2d c2 7f 00 00
stack at sp + 7 slots: 0x00007fc214c437a0 is pointing into the stack for thread: 0x00007fc224256800