Re: TEST and JS Question

On Mon, 31 Oct 2005 01:47:35 +0000 (UTC), spamtrap@xxxxxxxxxx wrote:

>On Sun, 30 Oct 2005 21:27:59 +0000 (UTC), Displacer
><spamtrap@xxxxxxxxxx> wrote:
>
>>Hi, been awhile since I've done asm . I know the test instruction just
>>does a and of the two regs, but it also sets flags like overflow and
>>sign. I can't for the life of me remember what sets the sign flag, so
>>if someone would help, here's the bit of code I need help figuring out
>>what its doing:
>>
>>test al,al
>>js somewhere
>
>
>If the H/O bit of al is set, that is the sign. Any of: (0x80 - 0xff).
>
>If effect, the h/o bit of al is copied to the sign flag.
>
>>
>>
>>Thanks!

Thanks, I knew there were some bits that were transfered to the flags,
but couldn't remember which ones. So JS jumps if its a negative
number. I would have found this myself on google, but JS brings up
waves and waves of Java Script stuff, and there isn't much out there
on that opcode anyway.

.