# Calculates gcd of 2 numbers
# lab04 of Computer Architecture course
#  at CSE.UoI.gr

        .data
n1:
        .word  462
n2:
        .word  1071
result:
        .word 0

        .globl main

        .text
main:

        la   $s0, n1       # Get address of n1
        lw   $a0, 0($s0)   # Get n1

        lw   $a1, 4($s0)   # Get n2

        jal  gcd

        la   $t0, result  # Address where the result should go to
        sw   $v0, 0($t0)

        # end the program
        li   $v0, 10
        syscall

                ######################################
        # Write your code here for mod and gcd
mod:

        sub   $a0, $a0, $a1
        bne   $a0, $a1, exitloop
        j     mod

exitloop:
	 slt   $a0, $a1, $a0
         add   $v0, $a0, $zero
         jal   gcd

gcd:
        slt   $a0, $a1, $a0
        add   $t1, $a0, $zero
        add   $a0, $a1, $zero
        add   $a1, $t1, $zero
        beq   $a1, $zero, zero
        add   $a0, $v0, $zero
        jal   mod

zero:
        addi  $sp, $sp, -4
        sw    $a1, 0($sp)
        add   $v0, $a0, $zero
        lw    $a1, 0($sp)
        addi  $sp, $sp, 4
        jr    $ra