vmf_sp
vmf->vmf_sp -= 2;
vm86_suword16(MAKE_ADDR(vmf->vmf_ss, vmf->vmf_sp), x);
vmf->vmf_sp -= 4;
vm86_suword(MAKE_ADDR(vmf->vmf_ss, vmf->vmf_sp), x);
u_short x = vm86_fuword16(MAKE_ADDR(vmf->vmf_ss, vmf->vmf_sp));
vmf->vmf_sp += 2;
u_int x = vm86_fuword(MAKE_ADDR(vmf->vmf_ss, vmf->vmf_sp));
vmf->vmf_sp += 4;
vmf->vmf_sp = (uintptr_t)stack;