[amelius]

Wouldn't that be equivalent to loading i and N into registers, so that a conditional jump would be fast?

  i=0
  StartLoop:
  i+=1
  do_stuff_0
  do_stuff_1
  REG1 = i, REG2 = N
  do_stuff_2
  do_stuff_3
  if REG1<REG2 goto StartLoop