Help Need Assembler help please

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Need Assembler help please - superMatas2 - Dec 15, 2016

Hi,
I know i have little chance to get free help in here you all gold diggers but it's worth a try.
So I need some help in assembly coding for MIPS-32.
I need to write 2 "programs":
One that exchanges the values from s0 and s1, for example if s0=4 and s1=3 then the "program" should exchange them so the result would be s0=3 ans s1=4.
This is my try but i think it's to easy to be true.(apparently i needed to use $zero. somwhere)

lw $t0, $s1
lw $t1, $s2
sw $t0, $s2
sw $t1, $s1

The other "program" need to take the absolute value from t0 to put it in t1, so t1 should be a positive umber or zero equal to t0 norm.(apparently i need to use something like bltz reg, addr commands)

It's probably not the best description of what i need to do but i needed to translate it and it wasn't the easiest part, let me know if you can help me please!👍

* - TouchMyMalware - Dec 15, 2016

I haven't touched MIPS but I just looked at the instruction set,
So this should work.

Code 
lw $s0, 4

lw $s1, 3

mflo $t1,$s0

mflo $s0,s1

mflo $s1,$t1

As for your second problem.

Code 
bltz $s0, negative

j positive

negative:

lw $s1,-1

mult $s0,$s1

mlfo $s0,$lo

positive:

#Should be now positive

Here is the instruction set.
http://www.mrc.uidaho.edu/mrc/people/jff/digital/MIPSir.html

Edit: mflo not mflw

* - superMatas2 - Dec 15, 2016

Hey Thanks a lot, just one question tho.. I never seen the mlfw command :(