Question

We assume the following

$s0 = a

$s1 = b

$s2 = c

$s3 = i

$s4 = address of ar[0]

Write MIPS assembly code for the following C code.

for (i = 10; i < 30; i ++)

{

if ((ar[i] > b) || (ar[i] <= c))

ar[i] = 0;

else

ar[i] = a;

}

Answer 1

# $s0 = a, $s1 = b, $s2 = c, $s3 = i, $s4 = address of ar[0]

li $s3, 0  # i = 0
for:   bge $s3, 30, end   # for (i < 30)
   
   sll $t0, $s3, 2       # i indexable
   add $t0, $t0, $s4  # $t0 = &ar[i]
   lw  $t1, 0($t0)       # $t1 = ar[i]
   
   bgt $t1, $s1, if   # if (ar[i] > b)
   ble $t1, $s2, if   # if  (ar[i] <= c)
   
   sw $s0, 0($t0) # else - ar[i] = a;
   j end
   if:
      sw $zero, 0($t0)   # if - ar[i] = 0;
   end:
   
   addi $s3, $s3, 1   # i++
   j for
end: