* bignum.c (rb_big_pow): Don't need to multiply SIZEOF_BDIGITS.
  Use nlz instead of bitlength_bdigit.
  (bitlength_bdigit): Removed.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41079 b2dd03c8-39d4-4d8f-98ff-823fe69b080e