The same alternative can produce very different instruction sequences.  For example:

  if (compare_sign_p (insn))
    {
      if (l) *l = 1;
      return AS1 (tst,%B0);
    }
  if (reg_unused_after (insn, op)
      && compare_eq_p (insn))
    {
      /* Faster than sbiw if we can clobber the operand.  */
      if (l) *l = 1;
      return AS2 (or,%A0,%B0);
    }
  if (test_hard_reg_class (ADDW_REGS, op))
    {
      if (l) *l = 1;
      return AS2 (sbiw,%0,0);
    }
  if (l) *l = 2;
  return (AS2 (cp,%A0,__zero_reg__) CR_TAB
          AS2 (cpc,%B0,__zero_reg__));