Question

Implement the following loop using MIPS assembly instructions. Assume that r, s, and t are stored in registers exists3, exists4, and exists5 respectively. while(s < t){ r = r + s: s = s + s: }

Answer 1

Sample Code:

.data

#add or initialize registers values here for r, s and t
#r: .word 1
#s: .word 10
#t: .word 20

.text

main:

la $s3, r    #load system call code into register $s3
la $s4, s   #load system call code into register $s4
la $s5, t   #load system call code into register $s5

syscall       #call system to print operation

Loop1: bgt $s4, $s5, EXIT #It will check whether s is greater than t s>t, if so exit or else proceed further.
   add $s3, $s3, $s4   # add r and s then assign the result to r
   add $s4, $s4, $s4   # add s with s and reassign the result to s
  
   j Loop1               # if s<t then call the loop and proceed futher or else exit.
EXIT: