# Divide - divide.dlx
# John Doe
# jcdoe
# Feb 31, 2001
# Updated and Converted to MIPS - Sept 10 2002

# Divide x by y.  Place the answer in quo.
# Both x and y are positive.  No error checking.
# Use integer division by repeated subtraction.

# Registers
#       $1 -- result
#       $2 -- x
#       $3 -- y
#       $4 -- base address of variables
#       $5 -- scratch

.globl main

# Get the x and y values
main:   llo     $4, x           # load base address
        lhi     $4, x
        lw      $2, 0($4)       # load x
        lw      $3, 4($4)       # load y

        add     $1, $0, $0      # init. answer

# loop, subtracting y from x, until x <= 0
subt:   sub     $2, $2, $3
        addi    $1, $1, 1       # incr answer

        addi    $5, $0, 1       # make equal to 1 since the next command checks strict inequality

        slti    $5, $2, 0       # is x <= 0?
        beq     $5, $0, subt    # no (ie $5 = 0) -- loop again
        j       end             # finished

        addi    $1, $1, -1      # correct for remainder

end:    sw      $1, 8($4)       # store the answer
        trap    10

        .align  4
x:      .word   15
y:      .word   3
quo:    .word   0