another assembly question

Owen

I'm having trouble executing code in assembly based on whether a variable is less than 0. can anyone explain to me
how this be written in assembly:

if variable < 0
execute code

sorry if this is too basic but I wasn't able to understand how to do this from the manual.

Thanks,

Owen

Mike Green

What you're actually testing is whether the sign bit (bit 31) of the variable is set and there are many ways to do this. The most straightforward way is just to do:

               cmps      variable,#0    wc
     if_nc   jmp        #:skipIt
' Here's the code to be executed
:skipIt

Skogsgurra

Something like this?

cmp t2,t3 wc
if_c jmp #os
' rest of code (negative part) goes here

os ' code for positive result

The trick, as I have understood it, is to remember to write the right flag - and then check it.

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Skogsgurra

Hmm... The ":" + "p" produced some unexpected results.

Anyhow, you got it from Mike. Trust him.

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Owen

Worked great! Thank you