执行PUSHAX指令时自动完成（）A①SP←SP，SS[SP]←AL②SP←SP，SS[SP]←AHB①SP←SP，SS[SP]←AH②SP←SP，SS[SP]←ALC①SP←SP+，SS[SP]←AL②SP←SP+，SS[SP]←AHD①SP←SP+，SS[SP]←AH②SP←SP+，SS[SP]←AL