Found by Olivier Mattmann <olivier.mattmann@bluewin.ch> during work on this Master thesis where he is working on a fuzzer for C2 (see JDK-8370562).

Running java-fastdebug -Xbatch -XX:-TieredCompilation -XX:CompileCommand=printcompilation,Test.test Test.java asserts with the following error on x64 and aarch64:
CompileCommand: PrintCompilation Test.test bool PrintCompilation = true
1812 103 % !b Test::test @ 53 (407 bytes)
1821 104 !b Test::test (407 bytes)
1824 105 % !b Test::test @ 336 (407 bytes)
o4378 If === o1875 o4377 o2561 [[ o4379 o4380 468 ]] P=0.000001, C=-1.000000

--N: o4378 If === o1875 o4377 o2561 [[ o4379 o4380 468 ]] P=0.000001, C=-1.000000

   --N: o4377 Bool === _ o2561 [[ o4378 ]] [ne]
   CMPOP 0 CMPOP
   CMPOPU 0 CMPOPU
   CMPOPUCF2 0 CMPOPUCF2

   --N: o2561 Phi === o2533 o2400 o716 [[ o4377 o4378 ]] #int:-1..1, 0u..maxuint
   RREGI 0 RREGI
   RAX_REGI 0 RAX_REGI
   RBX_REGI 0 RBX_REGI
   RCX_REGI 0 RCX_REGI
   RDX_REGI 0 RDX_REGI
   RDI_REGI 0 RDI_REGI
   NO_RAX_RDX_REGI 0 NO_RAX_RDX_REGI
   NO_RBP_R13_REGI 0 NO_RBP_R13_REGI
   STACKSLOTI 100 storeSSI

#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (src/jdk/open/src/hotspot/share/opto/matcher.cpp:1640), pid=274085, tid=274100
# assert(false) failed: bad AD file
#
# JRE version: Java(TM) SE Runtime Environment (27.0) (fastdebug build 27-internal-mhassig.open)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 27-internal-mhassig.open, mixed mode, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0x1688d13] Matcher::Label_Root(Node const*, State*, Node*, Node*&)+0x9c3

Current CompileTask:
C2:6138 688 % !b Test::test @ 356 (427 bytes)

Stack: [0x00007f198e5e7000,0x00007f198e6e7000], sp=0x00007f198e6e2830, free space=1006k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x1688d13] Matcher::Label_Root(Node const*, State*, Node*, Node*&)+0x9c3 (matcher.cpp:1640)
V [libjvm.so+0x1688eb8] Matcher::match_tree(Node const*)+0x158 (matcher.cpp:1424)
V [libjvm.so+0x168f73c] Matcher::xform(Node*, int)+0xd9c (matcher.cpp:1040)
V [libjvm.so+0x1693311] Matcher::match()+0x901 (matcher.cpp:337)
V [libjvm.so+0xbad606] Compile::Code_Gen()+0x236 (compile.cpp:3038)
V [libjvm.so+0xbb3373] Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x2123 (compile.cpp:895)
V [libjvm.so+0x9ca1e8] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x498 (c2compiler.cpp:147)
V [libjvm.so+0xbc2760] CompileBroker::invoke_compiler_on_method(CompileTask*)+0x780 (compileBroker.cpp:2345)
V [libjvm.so+0xbc3fc0] CompileBroker::compiler_thread_loop()+0x530 (compileBroker.cpp:1989)
V [libjvm.so+0x112d25b] JavaThread::thread_main_inner()+0x13b (javaThread.cpp:776)
V [libjvm.so+0x1bbbe06] Thread::call_run()+0xb6 (thread.cpp:243)
V [libjvm.so+0x1810bf8] thread_native_entry(Thread*)+0x118 (os_linux.cpp:929)

Build search suggests that this is caused by JDK-8280320.