Sorry for late reply, I reproduced this bug, but may need some time to figure out the reason.
#
# Fatal error in ../../src/objects/heap-object.h, line 220
# Check failed: !v8::internal::FLAG_enable_slow_asserts || (IsHeapObject()).
#
#
#
#FailureMessage Object: 0xfffbd19940
/home/loongson/workspace/v8/out/mips64el.debug/libv8_libbase.so(v8::base::debug::StackTrace::StackTrace()+0x44) [0xfff2a2eebc]
/home/loongson/workspace/v8/out/mips64el.debug/libv8_libplatform.so(+0x6ff70) [0xfff2953f70]
/home/loongson/workspace/v8/out/mips64el.debug/libv8_libbase.so(V8_Fatal(char const*, int, char const*, ...)+0x14c) [0xfff2a0437c]
./out/mips64el.debug/d8(v8::internal::HeapObject::HeapObject(unsigned long)+0xe8) [0xaaab1f4308]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(v8::internal::JSReceiver::JSReceiver(unsigned long)+0x4c) [0xfff4d59d74]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(v8::internal::TorqueGeneratedJSObject<v8::internal::JSObject, v8::internal::JSReceiver>::TorqueGeneratedJSObject(unsigned long)+0x4c) [0xfff4d4d5bc]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(v8::internal::JSObject::JSObject(unsigned long)+0x40) [0xfff4d4d550]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(v8::internal::WasmInstanceObject::WasmInstanceObject(unsigned long)+0x4c) [0xfff526a7c4]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(v8::internal::WasmInstanceObject::cast(v8::internal::Object)+0x58) [0xfff535ee68]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(v8::internal::WasmCompileLazyFrame::wasm_instance() const+0x74) [0xfff53e31f4]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(+0x39992b8) [0xfff63f52b8]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(v8::internal::Runtime_WasmCompileLazy(int, unsigned long*, v8::internal::Isolate*)+0x1ec) [0xfff63f4b94]
/home/loongson/workspace/v8/out/mips64el.debug/libv8.so(+0x1ce9844) [0xfff4745844]
Received signal 6
[1] 24375 abort ./out/mips64el.debug/d8 --test test/mjsunit/mjsunit.js --nohard-abort