            segment .data
    a       dq      100
    b       dq      200
            segment .text
            global  main
    main:
            push    rbp
            mov     rbp, rsp
            mov     rax, [a]
            mov     rbx, [b]
            cmp     rax, rbx
            jge     in_order
            mov     [a], rbx
            mov     [b], rax
    in_order:
            xor     eax, eax
            leave
            ret