I am working on a project that requires me to use MIPS to bubblesort an array. E

Question

I am working on a project that requires me to use MIPS to bubblesort an array. Everything is working but I cannot figure out why it is not sorting correctly. Here is the code:

.data
WellcomeReadText:
   .asciiz "Please enter integer numbers in the array: "
Array:
   .space 20   #5 integer array: 4 bytes for each integer.
  
#WellcomePrintText:       # Set a global variable for wellcome text
   .asciiz "Print out array:"
     
WhiteSpace:       # Set a global variable for white space
   .asciiz " "
  
prompt: .asciiz "Please enter the number of elements "

prompt2: .asciiz "Unsorted array "

prompt3: .asciiz " sorted array "

prompt4: .asciiz " outerloop "

prompt5: .asciiz " inner loop "

prompt6: .asciiz " update "

.globl main
.text

main:
#print prompt
la $a0 prompt
li $v0 4
syscall

#get int
li $v0 5
syscall

#allocate space
sll $a0 $v0 2 #number of bytes now in $a0
li $v0 9
syscall

#address of space now in $v0
add $t8, $a0, $zero
  

###################INPUT READIN###################
   li $v0, 4       #Let processor know we want to print out a string text (wellcome text)
   la $a0, WellcomeReadText   #load wellcometext address to $a0
   syscall  
           #Execute "print"
   la $t0, Array       #load array base address to $t0
   addi $t1, $zero, 0   #Setup array address offset to $t1

ReadLoop:
   li $v0, 5       #Let processor know we want to user input an integer
   syscall        #Execute "read"
   add $t2, $t1, $t0   #Calculate address for storing the input integer
   sb $v0, 0($t2)       #if we use "sw" here, system will check if the address is "word-aligned".
               #The address is word-aligned should be like 0xFFF0010, 0xFFF0014, 0xFFF0018.
               #However, random assign address by computer will not match this word=align policy.
               #We use "sb" (save byte) would solve the problem.
   addi $t1, $t1, 4       #Increase data offset by 4
   blt $t1, $t8, ReadLoop   #Compare if we have reached 5 input integers. If no, continue; if yes, stop
###################OUTPUT PRINT###################
   li $v0, 4       #Let processor know we are going to print out a string text.
   la $a0, prompt2   #Load string base address to $a0
   syscall           #Execute "print"
   la $a0, WhiteSpace   #Load the white space address to $a0
   syscall           #Execute "print"
   la $t0, Array       #Load Array address to $t0
   addi $t1, $zero, 0   #Setup array address offset to $t1

PrintLoop:
   add $t2, $t1, $t0   #Calculate address of the element in the Array
   li $v0, 1       #Let processor know we want to print out an integer
   lb $a0, 0($t2)       #load byte (instead of load word) from address $t2
   syscall           #Execute "print"
   li $v0, 4       #We want to print out a white space
   la $a0, WhiteSpace   #load white space address to $a0
   syscall           #Execute "print"
   addi $t1, $t1, 4       #Increase array address offset by 4
   blt $t1, $t8, PrintLoop   #Compare if we reach 5 elements
  
  
  
  
  
  
#######Bubblesort#######
la $t0, Array # move address of the array into $t0
li $s0, 1 # boolean flag = false 0 = false 1 = true
li $t2, 0 # j = 0;
li $t1, 0 # i = 0;

add $s3, $t8, $zero # array length n

Outerloop:
beqz $s0, exit # exit if flag = false
li $s0, 0 # flag = false;
addi $t2, $t2, 1 # j++;
move $t1, $0 # i = 0;
sub $s2, $s3, $t2 # s2 = length - j
li $v0, 4       #Let processor know we are going to print out a string text.
la $a0, prompt4   #Load string base address to $a0
syscall  

InnerLoop:
bge $t1, $s2, exitInnerLoop # if i>=s2, exit
lw $t1, 0($t0) # a0 = array[i]
lw $t2, 4($t0) # a1 = array[i+1]
ble $t1, $t2, update # if array[i]<=array[i+1] then forward i by 1
sw $t2, 0($t0) # a[i+1] = a[i]
sw $t1, 4($t0) # a[i] = a[i+1]
li $s0, 1 # flag = true;
li $v0, 4       #Let processor know we are going to print out a string text.
la $a0, prompt5   #Load string base address to $a0
syscall  

update:
li $v0, 4       #Let processor know we are going to print out a string text.
la $a0, prompt6   #Load string base address to $a0
syscall  
addi $t2, $t1, 4 # i++
sll $t3, $t1, 2 # t3 = i*4
add $t0, $t0, $t3 # point to next element -->
j InnerLoop

exitInnerLoop:
j Outerloop

exit:

####Print Sorted Array#######
   li $v0, 4       #Let processor know we are going to print out a string text.
   la $a0, prompt3   #Load string base address to $a0
   syscall           #Execute "print"
   la $a0, WhiteSpace   #Load the white space address to $a0
   syscall           #Execute "print"
   la $t0, Array       #Load Array address to $t0
   addi $t1, $zero, 0   #Setup array address offset to $t1

PrintLoop2:
   add $t2, $t1, $t0   #Calculate address of the element in the Array
   li $v0, 1       #Let processor know we want to print out an integer
   lb $a0, 0($t2)       #load byte (instead of load word) from address $t2
   syscall           #Execute "print"
   li $v0, 4       #We want to print out a white space
   la $a0, WhiteSpace   #load white space address to $a0
   syscall           #Execute "print"
   addi $t1, $t1, 4       #Increase array address offset by 4
   blt $t1, $t8, PrintLoop2   #Compare if we reach 5 elements

Explanation / Answer

Please find the link for source code below.

https://drive.google.com/file/d/0B9P4w87kevGhaE1xekRRbjJlYVE/view?usp=sharing

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