# compute the factorial of 9 using the following algorithm
#   N = 5
#   result = 1
#   while (N != 0) {
#     result = result * N
#     N = N - 1
#   }

N:      .word    5                      # reserve and initialize a word
result: .space   4                      # reserve but don't initalize a word
     
        addi    $t0, $0, 1              # $t0 will hold result, initially 1
        lw      $t1, N($gp)             # $t1 will hold N, initially 9
    
top:    beq     $t1, $0, bottom
        mult    $t0, $t0, $t1           # result = result * N
        addi    $t1, $t1, -1            # decrement N
        j       top                     # goto top
    
bottom:
        sw      $t0, result($gp)        # we'd better save result
        halt                            # all done