#  assert(!t->is_flat() && !t->is_not_flat()) failed: Should have been optimized out

Current CompileTask:
C2: 388771 32750    b        java.util.concurrent.ConcurrentLinkedQueue$CLQSpliterator::trySplit (132 bytes)

Stack: [0x00007f5e6d3fc000,0x00007f5e6d4fd000],  sp=0x00007f5e6d4f8490,  free space=1009k
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [libjvm.so+0x13d2be6]  PhaseMacroExpand::expand_flatarraycheck_node(FlatArrayCheckNode*)+0x106
V  [libjvm.so+0x13db581]  PhaseMacroExpand::expand_macro_nodes()+0xd71
V  [libjvm.so+0xa37b40]  Compile::Optimize()+0x1800
V  [libjvm.so+0xa397bd]  Compile::Compile(ciEnv*, ciMethod*, int, bool, bool, bool, bool, DirectiveSet*)+0x199d
V  [libjvm.so+0x85720c]  C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x1dc
V  [libjvm.so+0xa49670]  CompileBroker::invoke_compiler_on_method(CompileTask*)+0xca0
V  [libjvm.so+0xa4a178]  CompileBroker::compiler_thread_loop()+0x5a8
V  [libjvm.so+0x196d816]  JavaThread::thread_main_inner()+0x256
V  [libjvm.so+0x1974560]  Thread::call_run()+0x100
V  [libjvm.so+0x162bc86]  thread_native_entry(Thread*)+0x116