a function compare 2 string in mips - compare

Question

this function should simply verify if the input is equal to the string simolo1
even if I input exactly the same string the output is strings are not equal.
I am saving in the registers s2 and s3 the pointers to the arrays. then I compare each byte, if all of those are equal the program should finish and output 'strings are equal'
.data
prompt: .asciiz "Enter string ('.' to end) > "
dot: .asciiz "."
eqmsg: .asciiz "strings are equal\n"
nemsg: .asciiz "strings are not equal\n"
str1: .space 80
str2: .space 80
simbolo1: .asciiz "sasso"
simbolo2: .asciiz "carta"
simbolo3: .asciiz "forbice"
.text
.globl main
main:
# get first string
la $s2,str1
move $t2,$s2
jal getstr
la $s3, simbolo1
# string compare loop (just like strcmp)
cmploop:
lb $t2,($s2) # get next char from str1
lb $t3,($s3) # get next char from str2
bne $t2,$t3,cmpne # are they different? if yes, fly
beq $t2,$zero,cmpeq # at EOS? yes, fly (strings equal)
addi $s2,$s2,1 # point to next char
addi $s3,$s3,1 # point to next char
j cmploop
# strings are _not_ equal -- send message
cmpne:
la $a0,nemsg
li $v0,4
syscall
j main
# strings _are_ equal -- send message
cmpeq:
la $a0,eqmsg
li $v0,4
syscall
j main
# getstr -- prompt and read string from user
#
# arguments:
# t2 -- address of string buffer
getstr:
# prompt the user
la $a0,prompt
li $v0,4
syscall
# read in the string
move $a0,$t2
li $a1,79
li $v0,8
syscall
# should we stop?
la $a0,dot # get address of dot string
lb $a0,($a0) # get the dot value
lb $t2,($t2) # get first char of user string
beq $t2,$a0,exit # equal? yes, exit program
jr $ra # return
# exit program
exit:
li $v0,10
syscall