519 xchg RAX, RCX  label
520 xchg RCX, RAX  label
521 xchg EAX, ECX  label
522 xchg ECX, EAX  label
523 xchg AX, CX  label
524 xchg CX, AX  label
532 xchg RAX, [ECX]  label
533 xchg [ECX], RAX  label
534 xchg EAX, [ECX]  label
535 xchg [ECX], EAX  label
536 xchg AX, [ECX]  label
537 xchg [ECX], AX  label