CMP
#define CMP(OP) ({ int r; BOTH_PRmn(OP##_X,r); r; })
#define CMP(aa, bb) ((aa) == (bb) ? 0 : (aa) < (bb) ? -1 : 1)
#define CMP 0x40 /* sta: arbitration complete */
#define CMP 0x40 /* sta: arbitration complete */