text: ///////////////////////////////////////////////////////////////////////////////
  //  Copyright 2012 John Maddock.
  //  Copyright Christopher Kormanyos 2013. Distributed under the Boost
  //  Software License, Version 1.0. (See accompanying file
  //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  //
  
  #ifndef BOOST_MP_UTYPE_HELPER_HPP
  #define BOOST_MP_UTYPE_HELPER_HPP
  
  #include <limits>
  #include <boost/cstdint.hpp>
  
  namespace boost {
  namespace multiprecision {
  namespace detail {
  template <const unsigned>
  struct utype_helper
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<0U>
  {
     typedef boost::uint8_t exact;
  };
  template <>
  struct utype_helper<1U>
  {
     typedef boost::uint8_t exact;
  };
  template <>
  struct utype_helper<2U>
  {
     typedef boost::uint8_t exact;
  };
  template <>
  struct utype_helper<3U>
  {
     typedef boost::uint8_t exact;
  };
  template <>
  struct utype_helper<4U>
  {
     typedef boost::uint8_t exact;
  };
  template <>
  struct utype_helper<5U>
  {
     typedef boost::uint8_t exact;
  };
  template <>
  struct utype_helper<6U>
  {
     typedef boost::uint8_t exact;
  };
  template <>
  struct utype_helper<7U>
  {
     typedef boost::uint8_t exact;
  };
  template <>
  struct utype_helper<8U>
  {
     typedef boost::uint8_t exact;
  };
  
  template <>
  struct utype_helper<9U>
  {
     typedef boost::uint16_t exact;
  };
  template <>
  struct utype_helper<10U>
  {
     typedef boost::uint16_t exact;
  };
  template <>
  struct utype_helper<11U>
  {
     typedef boost::uint16_t exact;
  };
  template <>
  struct utype_helper<12U>
  {
     typedef boost::uint16_t exact;
  };
  template <>
  struct utype_helper<13U>
  {
     typedef boost::uint16_t exact;
  };
  template <>
  struct utype_helper<14U>
  {
     typedef boost::uint16_t exact;
  };
  template <>
  struct utype_helper<15U>
  {
     typedef boost::uint16_t exact;
  };
  template <>
  struct utype_helper<16U>
  {
     typedef boost::uint16_t exact;
  };
  
  template <>
  struct utype_helper<17U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<18U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<19U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<20U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<21U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<22U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<23U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<24U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<25U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<26U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<27U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<28U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<29U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<30U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<31U>
  {
     typedef boost::uint32_t exact;
  };
  template <>
  struct utype_helper<32U>
  {
     typedef boost::uint32_t exact;
  };
  
  template <>
  struct utype_helper<33U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<34U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<35U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<36U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<37U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<38U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<39U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<40U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<41U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<42U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<43U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<44U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<45U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<46U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<47U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<48U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<49U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<50U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<51U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<52U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<53U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<54U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<55U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<56U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<57U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<58U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<59U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<60U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<61U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<62U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<63U>
  {
     typedef boost::uint64_t exact;
  };
  template <>
  struct utype_helper<64U>
  {
     typedef boost::uint64_t exact;
  };
  
  template <class unsigned_type>
  int utype_prior(unsigned_type ui)
  {
     // TBD: Implement a templated binary search for this.
     int priority_bit;
  
     unsigned_type priority_mask = unsigned_type(unsigned_type(1U) << (std::numeric_limits<unsigned_type>::digits - 1));
  
     for (priority_bit = std::numeric_limits<unsigned_type>::digits - 1; priority_bit >= 0; --priority_bit)
     {
        if (unsigned_type(priority_mask & ui) != unsigned_type(0U))
        {
           break;
        }
  
        priority_mask >>= 1;
     }
  
     return priority_bit;
  }
  
  }}} // namespace boost::multiprecision::detail
  
  #endif // BOOST_MP_UTYPE_HELPER_HPP
  