Divide
div: # fn div(int x, int y) -> int
addi a0, x0, 0 # res = 0
div_loop:
blt a1, a2, div_return # if x < y { goto div_return }
sub a1, a1, a2 # x = x - y
addi a0, a0, 1 # res = res + 1
j div_loop # goto div_loop
div_return:
jr ra # return res