Question

Write a short piece of assembly language code in MIPS that will compute the sum of the values in array A. Assume the base address of A is in $s0 and the number of values in array A is held in $s2.

Answer 1

addi $s1, $zero, 0 # initialize i to 0

Loop: slt $t1, $s1, $s2 # Set if i < $s2

beq $t1, $zero, Exit # Exit if i >= $s2

addi $t1, $s1, 5 # Add 5 to i, store in t1

sll $t2, $s1, 2 # Calculate i*4, store in t2

add $t2, $t2, $so # Calculate address of a[i]

sw $t1, 0($t2) # Store t1 to element address

addi $s1, $s1, 1 # Increment i

j Loop # Go to next iteration

Exit:

This is the simple MIPS program which calculates the SUM of all the elements of array, the Base address of Array is stored in $s0, and The size of array is stored in $s2.