STACK_RESERVE
if (STACK_RESERVE(lms.lms_cexp_val_stack,
if (STACK_RESERVE(lms.lms_cdir_stack, CDIR_STACK_INIT) == 0)
if (STACK_RESERVE(lms.lms_cexp_op_stack, CEXP_OP_STACK_INIT) == 0)
fp = (caddr_t)rp->r_sp - STACK_RESERVE;