When run with -XX:+UseAtomicValueFlattening, test compiler/valhalla/inlinetypes/TestFlatArrayAliasesCardMark.java crashes with the following message:

# Internal Error (/valhalla/open/src/hotspot/share/opto/compile.cpp:5741), pid=2280567, tid=2280585
# assert(bt == T_SHORT) failed: unexpected narrow type
#
# JRE version: Java(TM) SE Runtime Environment (25.0) (fastdebug build 25-lworld5ea-LTS-2025-03-28-1144114.fred...)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 25-lworld5ea-LTS-2025-03-28-1144114.fred..., mixed mode, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0xabecef] Compile::narrow_value(BasicType, Node*, Type const*, PhaseGVN*, bool)+0x2ef
#


Stack trace:

Current thread (0x0000732aa02816d0): JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=2280585, stack(0x0000732a9ff00000,0x0000732aa0000000) (1024K)]


Current CompileTask:
C2:1813 336 % b 4 TestFlatArrayAliasesCardMark::method1 @ 16 (57 bytes)

Stack: [0x0000732a9ff00000,0x0000732aa0000000], sp=0x0000732a9fffc170, free space=1008k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0xabecef] Compile::narrow_value(BasicType, Node*, Type const*, PhaseGVN*, bool)+0x2ef (compile.cpp:5741)
V [libjvm.so+0xf678bf] InlineTypeNode::convert_from_payload(GraphKit*, BasicType, Node*, int, bool, int)+0x1cf (inlinetypenode.cpp:609)
V [libjvm.so+0xf683c9] InlineTypeNode::make_from_flat_impl(GraphKit*, ciInlineKlass*, Node*, Node*, Node*, ciInstanceKlass*, int, bool, int, unsigned long, GrowableArray<ciType*>&)+0x3b9 (inlinetypenode.cpp:1429)
V [libjvm.so+0xf6c35e] InlineTypeNode::make_from_flat(GraphKit*, ciInlineKlass*, Node*, Node*, Node*, ciInstanceKlass*, int, bool, int, unsigned long)+0x10e (inlinetypenode.cpp:1312)
V [libjvm.so+0x170fda3] Parse::array_load(BasicType)+0x8c3 (parse2.cpp:130)
V [libjvm.so+0x171ed6b] Parse::do_one_bytecode()+0x86b (parse2.cpp:2969)
V [libjvm.so+0x17064dd] Parse::do_one_block()+0x35d (parse1.cpp:1664)
V [libjvm.so+0x1707745] Parse::do_all_blocks()+0x135 (parse1.cpp:754)
V [libjvm.so+0x170b202] Parse::Parse(JVMState*, ciMethod*, float)+0xeb2 (parse1.cpp:658)
V [libjvm.so+0x8fa565] ParseGenerator::generate(JVMState*)+0x135 (callGenerator.cpp:98)
V [libjvm.so+0xaccb56] Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x17f6 (compile.cpp:811)
V [libjvm.so+0x8f75ad] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x46d (c2compiler.cpp:142)
V [libjvm.so+0xadab8c] CompileBroker::invoke_compiler_on_method(CompileTask*)+0xbfc (compileBroker.cpp:2331)
V [libjvm.so+0xadbac8] CompileBroker::compiler_thread_loop()+0x598 (compileBroker.cpp:1975)
V [libjvm.so+0x101c47f] JavaThread::thread_main_inner()+0x12f (javaThread.cpp:777)
V [libjvm.so+0x1a28e46] Thread::call_run()+0xb6 (thread.cpp:231)
V [libjvm.so+0x16b8378] thread_native_entry(Thread*)+0x128 (os_linux.cpp:877)
C [libc.so.6+0x9caa4]