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- #ifndef BOOST_INTEGER_INTEGER_MASK_HPP
- #define BOOST_INTEGER_INTEGER_MASK_HPP
- #include <boost/integer_fwd.hpp>
- #include <boost/config.hpp>
- #include <boost/integer.hpp>
- #include <climits>
- #include <cstddef>
- #include <boost/limits.hpp>
- namespace boost
- {
- template < std::size_t Bit >
- struct high_bit_mask_t
- {
- typedef typename uint_t<(Bit + 1)>::least least;
- typedef typename uint_t<(Bit + 1)>::fast fast;
- BOOST_STATIC_CONSTANT( least, high_bit = (least( 1u ) << Bit) );
- BOOST_STATIC_CONSTANT( fast, high_bit_fast = (fast( 1u ) << Bit) );
- BOOST_STATIC_CONSTANT( std::size_t, bit_position = Bit );
- };
- template < std::size_t Bits >
- struct low_bits_mask_t
- {
- typedef typename uint_t<Bits>::least least;
- typedef typename uint_t<Bits>::fast fast;
- BOOST_STATIC_CONSTANT( least, sig_bits = (~( ~(least( 0u )) << Bits )) );
- BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );
- BOOST_STATIC_CONSTANT( std::size_t, bit_count = Bits );
- };
- #define BOOST_LOW_BITS_MASK_SPECIALIZE( Type ) \
- template < > struct low_bits_mask_t< std::numeric_limits<Type>::digits > { \
- typedef std::numeric_limits<Type> limits_type; \
- typedef uint_t<limits_type::digits>::least least; \
- typedef uint_t<limits_type::digits>::fast fast; \
- BOOST_STATIC_CONSTANT( least, sig_bits = (~( least(0u) )) ); \
- BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) ); \
- BOOST_STATIC_CONSTANT( std::size_t, bit_count = limits_type::digits ); \
- }
- BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned char );
- #if USHRT_MAX > UCHAR_MAX
- BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned short );
- #endif
- #if UINT_MAX > USHRT_MAX
- BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned int );
- #endif
- #if ULONG_MAX > UINT_MAX
- BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned long );
- #endif
- #undef BOOST_LOW_BITS_MASK_SPECIALIZE
- }
- #endif
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