Building the Loop

Perhaps you added one to the base register, rather than four. The base register $9 needs to be increased by the size of a full word, four. Now work on getting the loop correct. The beq instruction branches out of the loop if the count has reached the end of the array.

At the bottom of the loop, the count is incremented and the base register is moved to the next array entry.


## Registers:
##  $8 -- count                     
##  $9 -- pointer to the array entry
## $10 -- current array entry       
## $11 -- sum of all integers       
## $12 -- sum of negative integers
## $13 -- sum of positive integers
## $14 -- pos. or neg. flag
## $15 -- SIZE of the array

main:    ori      $8,$0,0        #  count = 0
         ori      $11,$0,0       #  sum = 0
         ori      $12,$0,0       #  neg = 0
         ori      $13,$0,0       #  pos = 0
         lui      $9,0x1000      #  point at SIZE

         lw       $15,0($9)      #  get SIZE
         addiu    $9,$9,4        #  point to first array entry

# while  count <  SIZE do

loop:    beq      $,$,done 

         sll      $0,$0,0        #  branch delay

         . . . . .               #  middle of loop body
         
         
         addiu    $8,$8,     # count++
         
         addiu    $9,$9,     # point at next entry
         
         j        loop
         sll      $0,$0,0        #  branch delay

done:    sll      $0,$0,0        #  target for branch

        .data
size:   .word  17
array:  .word  12, -1, 8, 0, 6, 85, -74, 23, 99, -30, 30, 95, 4, 7, 10, 28, 14

Answer:

Building the Loop

QUESTION 11: