The attached fuzzer test fails intermittently with the following assertion:

To reproduce (fails 1 out of 3-4 runs):
$ java -XX:RepeatCompilation=100 Test.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-S79226/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/0cb697b6-5006-4d18-afca-8f82d7082f5e/runs/5d51f3ad-e036-4803-805d-9e13517ddb05/workspace/open/src/hotspot/share/opto/cfgnode.cpp:1972), pid=14706, tid=14725
# assert(phi_type->isa_int() || phi_type->isa_ptr() || phi_type->isa_long()) failed: bad phi type
#
# JRE version: Java(TM) SE Runtime Environment (17.0+25) (fastdebug build 17-ea+25-LTS-2214)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 17-ea+25-LTS-2214, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0x893a5a] PhiNode::Ideal(PhaseGVN*, bool)+0xfaa
.............
Command Line: -XX:RepeatCompilation=100 --add-modules=ALL-DEFAULT jdk.compiler/com.sun.tools.javac.launcher.Main Test.java
.............
Current thread (0x00007f2e1c1acb40): JavaThread "C2 CompilerThread1" daemon [_thread_in_native, id=14725, stack(0x00007f2e499f9000,0x00007f2e49afa000)]


Current CompileTask:
C2: 12185 699 % ! 4 Test::mainTest @ 261 (642 bytes)

Stack: [0x00007f2e499f9000,0x00007f2e49afa000], sp=0x00007f2e49af4830, free space=1006k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x893a5a] PhiNode::Ideal(PhaseGVN*, bool)+0xfaa
V [libjvm.so+0x15fd5d8] PhaseIterGVN::transform_old(Node*)+0xb8
V [libjvm.so+0x15f63ae] PhaseIterGVN::optimize()+0x7e
V [libjvm.so+0xa1ddea] PhaseIdealLoop::optimize(PhaseIterGVN&, LoopOptsMode)+0x69a
V [libjvm.so+0xa1a1dc] Compile::Optimize()+0x12ec
V [libjvm.so+0xa1bec5] Compile::Compile(ciEnv*, ciMethod*, int, bool, bool, bool, bool, DirectiveSet*)+0x1585
V [libjvm.so+0x841aba] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x1ea
V [libjvm.so+0xa2c889] CompileBroker::invoke_compiler_on_method(CompileTask*)+0xfb9
V [libjvm.so+0xa2d5f8] CompileBroker::compiler_thread_loop()+0x5a8
V [libjvm.so+0x18a3a11] JavaThread::thread_main_inner()+0x271
V [libjvm.so+0x18ab610] Thread::call_run()+0x100
V [libjvm.so+0x157721e] thread_native_entry(Thread*)+0x10e