MIPS programming.

I want to find a subroutine to check whether an input integer is a perfect square.

My strategy is compute the square of integer from 1 and incrementing the number. Until the i^2 no longer smaller than the input. we can check whether is equal or larger than some i^2. But it does not run as what is expected

square: add $t0, $zero, $a0 slt $t8, $zero, $t0 beq $t8, $zero, edge addi $t1, $zero, 1 # a = input # if 0