MIPS Tutorial 16 Function Arguments and Return Values Video Lecture | MIPS Assembly Programming Simplified - Electronics and Communication Engineering (ECE)

hello guys this is a Mel and welcome
back
well last time I think I was trying to
confuse you guys with these functions
and procedures but well you know it's
time for me to teach you more about it
and well this time I want to teach you
about arguments and return values so
functions or procedures as I told you
they allow you to reuse code and to keep
and to make your code more readable
because you can just let's say define or
make your own functions down here and
whenever you wanna use that you just
call it and this is calling a function
and this is making a function or
defining a function defining a function
or procedure and this is calling a
procedure so yes but you know you can
pass you can pass values to two
procedures and you can also get values
from procedures and this is um what is
tutorial is about today these tutorial
is about passing arguments or passing
values because values they're called
arguments when you're passing them to
procedures and getting those values back
so um this is what we're gonna do right
here I'm gonna make a simple I'm not
gonna use this right here I want to use
this message because I want to make this
tutorial kind of complicated so um you
know that right here I'm gonna make and
this this method right here is gonna be
let me delete delete this right here add
numbers and as the name implies this is
gonna add two numbers so what are the
numbers what are the numbers that I want
to what are the numbers that I want to
add okay so we have to pass those values
as arguments to the function but how how
do we pass them by as values how do we
do that well by convention you don't
have to put by convention and this is
the good way to do it
we use these registers right here the a
registers to pass arguments
two functions to pass values so we have
four of them we have a 0 a 1 a 2 a 3 so
let's say we want to add two numbers we
want to add two numbers together
so what we do is that we have to put the
values in in those registers in in the a
registers so we're gonna say add
immediate
they'll assign a 1 for example Dell
assign 0
come on let's say I want to add 50 ok
and this is going to be my first
argument so 50 is going to be stored in
a 1 so this is gonna be my first
argument for the function the first
number that I want to add and the second
number is gonna be in a - I do media
that assign it to coma that assigns 0
and the number is gonna be 100 so right
now I have a 1 has 50 in a 2 has 100 and
I want to know I want to know the answer
I want to know what the answer is so now
I can use these registers inside the
function inside the procedure at numbers
so let me do this I'm gonna need it but
I'm gonna tell you right now so let me
define the function at numbers I'm going
to delete this tool because I want to
just make it clear so I'm making my
function right here add numbers this is
the label and then I'm gonna say okay
add that assign v1l assign a 1 dollar
sign 8 - jump register the law sign RA
so what this means is that um I'm
storing that I'm adding like
these number fifty and this number 100
so this is addition and the sum or the
result is going to be stored in v1 but
why v1 well by convention programmers
they decide to store the sum in v1
because this is for return values so
we're going to use v1 in main function
or in the main procedure to actually see
the result or to see the song so finally
we have to say jump register that assign
are a to go back to the to the column
place so we should see 150
so now let's test it so what we do now
is that we come here and we want to
print out the value so we say loaded
media that assigned V 0 comma 1 to brain
integer and we say add immediate they'll
assign a zero dollar sign zero that I
mean not zero but the sign V 0 comma 0
or V 1 actually because the values in V
1 so finally we do
Sisco and then we should see 150 down
there so save run assemble clear execute
and voila
150 so this is just teaching you how to
use convention if you want to pass
arguments to a function to give it
arguments or values always use the a
registers in this case I used a 1 and a
2 and when you do the calculation and
you wanna give it back to the color or
the main function use the V register so
that's why I store the result in B 1 and
here I just printed I just printed out
the some of the result using this V V 1
as as the argument so thank you for
watching I hope you enjoyed this
tutorial and well see you next time
right I have a have a good day