How should a x86 emulator respond to FPU opcodes (FWAIT and ESC) without a FPU present? I've just adjusted FINIT to do nothing, FSTSW, FNSTSW and FNSTCW to write FFFFh to the destination r/m16. And all other FPU opcodes do nothing (NOP).

And when CR0.TS or CR0.EM is set, it will trigger a #NM exception to allow the software to emulate it properly (or fault if it wants to).

What happens on real hardware with this x86 CPU without FPU? How is it actually detected to be properly not present?