as far as i remember, MBR code is as compact as possible, since the
space is limited.
would it be appropriate to twist some code in order to win some space?
like the following:

On 2/21/10, Giuseppe Magnotta <[email protected]> wrote:
...
>         movw    $NDOSPART, %cx
>  +       xorw    %ax, %ax
>  +       xorw    %bx, %bx
>  +
>  +test_pt:
>  +       movb    (%si), %al
>  +       addw    %ax, %bx
>  +       addw    $PARTSZ, %si
>  +       loop    test_pt
>  +
>  +       cmpw    $0x0, %bx

if my memory serves me right, that operation takes 3 bytes, "orw
%bx,%bx" whould take 2 with the same result... in my days of using
assembly of 8086 it was quite common technic (like doing xor instead
of movw zero).

>  +       je      no_part
>  +
>  +       cmpw    $DOSACTIVE, %bx
>  +       jne     more_part
...

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