* bignum.c (bary_cmp): Extracted from rb_big_cmp.
  (power_cache_get_power): Change n1 argument (number of digits) to
  power_level which is just passed to power_cache_get_power0.
  (big2str_karatsuba): Ditto.
  (rb_big2str1): Calculate the initial power_level.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42285 b2dd03c8-39d4-4d8f-98ff-823fe69b080e