JDK-8289954 fixed an assertion failure issue found in a fuzzer test and added a new jtreg case "compiler/loopopts/TestUnreachableInnerLoop.java" as a regression test. But after that fix, the new test case still fails on RISC-V port.

# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/home/fyang/openjdk-jdk/src/hotspot/share/opto/block.cpp:1249), pid=2130903, tid=2130918
# assert(n->is_Root() || n->is_Region() || n->is_Phi() || n->is_MachMerge() || def_block->dominates(block)) failed: uses must be dominated by definitions

Current CompileTask:
C2: 1896 22 % !b 4 compiler.loopopts.TestUnreachableInnerLoop::fun @ 61 (233 bytes)

Stack: [0x0000003fc041a000,0x0000003fc061a000], sp=0x0000003fc0614850, free space=2026k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x416ade] PhaseCFG::verify() const+0x1d4
V [libjvm.so+0x7150d2] Compile::Code_Gen()+0x284
V [libjvm.so+0x7196d4] Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x11d4
V [libjvm.so+0x55c4ec] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x258
V [libjvm.so+0x725da8] CompileBroker::invoke_compiler_on_method(CompileTask*)+0x8c4
V [libjvm.so+0x726972] CompileBroker::compiler_thread_loop()+0x61c
V [libjvm.so+0xb8e7ee] JavaThread::thread_main_inner()+0x258
V [libjvm.so+0x14080b2] Thread::call_run()+0xd4
V [libjvm.so+0x106189c] thread_native_entry(Thread*)+0xee
C [libc.so.6+0x66e94]
C [libc.so.6+0xb2962]