Fibonacci MIPS32 | Example | Step by Step

fibonacci.asm

#Fibonacci MIPS32
#Author: Kelvin Nose: :^)
#Date: 10/30/15

#int count = 0;
#int n = 0;
#int first = 0;
#int second = 1;
#int next = 0;
#int c;
#   for ( c = 0 ; c < n ; c++ )
#   {
#      if ( c <= 1 )
#         next = c;
#      else
#      {
#         next = first + second;
#         first = second;
#         second = next;
#      }
#      printf("%d\n",next);
#   }

.data
	# Default variable values
	count: .word 0
	n: .word 7
	first: .word 0
	second: .word 1
	next: .word 0
	c: .word 0
	
.text
	main:
		lw $t0, c #set c contents to $t0
		lw $t1, n #set n (number of fibonacci terms) to $t1
		lw $t2, next  #set next contents to $t2
		lw $t3, first #set first contents to $t3
		lw $t4, second  #set second contents to $t4
		j loop #jumps to loop to start for(c=0 ; c<n; c++)
				
		#Default label for if(c<= 1) cases	
		default:
			sw $t0, next($t2) #stores content of c in next // next = c
			addi $t0, $t0, 1 #increments c by 1 // c++
			j loop # jumps to loop to continue until c<n
		
		#for loop content
		loop:
			ble $t0, 1, default #evaluate if(c<=1) if true, then go to default label
			add $t2, $t3, $t4   #adding and storing values of first and second //next = first+second
			add $t3, $zero, $t4 #stores contents of second into first // first = second
			add $t4, $zero, $t2 #stores contents of next into second // second = next
			addi $t0, $t0, 1 #increments c by 1 // c++
			blt $t0, $t1, loop #go to loop if c < n