mirror of
https://github.com/boostorg/integer.git
synced 2025-07-01 06:51:01 +02:00
395 lines
14 KiB
C++
395 lines
14 KiB
C++
// boost integer.hpp header file -------------------------------------------//
|
|
|
|
// Copyright Beman Dawes and Daryle Walker 1999. 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)
|
|
|
|
// See http://www.boost.org/libs/integer for documentation.
|
|
|
|
// Revision History
|
|
// 16 Jul 08 Added MPL-compatible variants of the minimum-size and value-
|
|
// based integer templates. (Daryle Walker)
|
|
// 15 Jul 08 Added exact-integer templates; added MPL-compatible variant of
|
|
// processor-optimized integer template. (Daryle Walker)
|
|
// 14 Jul 08 Added extended-integer support. (Daryle Walker)
|
|
// 13 Jul 08 Redid implmentation. (Daryle Walker)
|
|
// 22 Sep 01 Added value-based integer templates. (Daryle Walker)
|
|
// 01 Apr 01 Modified to use new <boost/limits.hpp> header. (John Maddock)
|
|
// 30 Jul 00 Add typename syntax fix (Jens Maurer)
|
|
// 28 Aug 99 Initial version
|
|
|
|
#ifndef BOOST_INTEGER_HPP
|
|
#define BOOST_INTEGER_HPP
|
|
|
|
#include <boost/integer_fwd.hpp> // self include
|
|
|
|
#include <boost/config.hpp> // for BOOST_STATIC_CONSTANT, etc.
|
|
#include <boost/cstdint.hpp> // for boost::uintmax_t, intmax_t
|
|
#include <boost/integer_traits.hpp> // for boost::integer_traits
|
|
#include <boost/limits.hpp> // for std::numeric_limits
|
|
#include <boost/utility/enable_if.hpp> // for boost::enable_if_c
|
|
|
|
#include <climits> // for UCHAR_MAX, USHRT_MAX, UINT_MAX, ULONG_MAX, etc.
|
|
|
|
namespace boost
|
|
{
|
|
|
|
// integer template mapping a type to its processor-optimized analog -----//
|
|
|
|
// Some types can be handled better by the processor than others. This
|
|
// template metafunction should map various built-in integral types to
|
|
// the processor's perferred type for the given type's value range
|
|
template < typename BaseInt >
|
|
struct fast_integral
|
|
{
|
|
typedef BaseInt type;
|
|
};
|
|
|
|
// Platform-specific specializations should go here.
|
|
|
|
// fast integers from least integers
|
|
// int_fast_t<> works correctly for unsigned too, in spite of the name.
|
|
template< typename LeastInt >
|
|
struct int_fast_t { typedef typename fast_integral<LeastInt>::type fast; };
|
|
|
|
namespace detail
|
|
{
|
|
|
|
// Helper templates ------------------------------------------------------//
|
|
|
|
// convert integer category to type ; default is empty
|
|
template< int Rank, typename Signedness > struct int_least_helper {};
|
|
|
|
// specializatons: 1=(unsigned) __int64/long long, 2=(unsigned) long,
|
|
// 3=unsigned/int, 4=(unsigned) short, 5=(un)signed char
|
|
// no specializations for 0: requests for a type > (unsigned) (long) long are
|
|
// in error
|
|
#ifdef BOOST_HAS_LONG_LONG
|
|
template<> struct int_least_helper<1, signed>
|
|
{ typedef long_long_type least; };
|
|
template<> struct int_least_helper<1, unsigned>
|
|
{ typedef ulong_long_type least; };
|
|
#elif defined(BOOST_HAS_MS_INT64)
|
|
template<> struct int_least_helper<1, signed> { typedef __int64 least; };
|
|
template<> struct int_least_helper<1, unsigned>
|
|
{ typedef unsigned __int64 least; };
|
|
#endif
|
|
template<> struct int_least_helper<2, signed> { typedef long least; };
|
|
template<> struct int_least_helper<2, unsigned>
|
|
{ typedef unsigned long least; };
|
|
template<> struct int_least_helper<3, signed> { typedef int least; };
|
|
template<> struct int_least_helper<3, unsigned>
|
|
{ typedef unsigned int least; };
|
|
template<> struct int_least_helper<4, signed> { typedef short least; };
|
|
template<> struct int_least_helper<4, unsigned>
|
|
{ typedef unsigned short least; };
|
|
template<> struct int_least_helper<5, signed> { typedef signed char least; };
|
|
template<> struct int_least_helper<5, unsigned>
|
|
{ typedef unsigned char least; };
|
|
|
|
// category bounds
|
|
enum
|
|
{
|
|
#if defined(BOOST_HAS_LONG_LONG) || defined(BOOST_HAS_MS_INT64)
|
|
lowest_integral_rank = 1,
|
|
#else
|
|
lowest_integral_rank = 2,
|
|
#endif
|
|
highest_integral_rank = 5
|
|
};
|
|
|
|
// map a bit count to a category
|
|
template < int BitsIncludingSign >
|
|
struct int_rank_helper
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, mantissa = BitsIncludingSign - 1 );
|
|
BOOST_STATIC_CONSTANT( int, rank = (BitsIncludingSign > 0) * (
|
|
#ifdef BOOST_HAS_LONG_LONG
|
|
(mantissa <= std::numeric_limits< long_long_type >::digits) +
|
|
#elif defined(BOOST_HAS_MS_INT64)
|
|
(mantissa <= std::numeric_limits< __int64 >::digits) +
|
|
#else
|
|
1 +
|
|
#endif
|
|
(mantissa <= std::numeric_limits< long >::digits) +
|
|
(mantissa <= std::numeric_limits< int >::digits) +
|
|
(mantissa <= std::numeric_limits< short >::digits) +
|
|
(mantissa <= std::numeric_limits< signed char >::digits)) );
|
|
};
|
|
|
|
template < int Bits >
|
|
struct uint_rank_helper
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, rank = (Bits >= 0) * (
|
|
#ifdef BOOST_HAS_LONG_LONG
|
|
(Bits <= std::numeric_limits< ulong_long_type >::digits) +
|
|
#elif defined(BOOST_HAS_MS_INT64)
|
|
(Bits <= std::numeric_limits< unsigned __int64 >::digits) +
|
|
#else
|
|
1 +
|
|
#endif
|
|
(Bits <= std::numeric_limits< unsigned long >::digits) +
|
|
(Bits <= std::numeric_limits< unsigned int >::digits) +
|
|
(Bits <= std::numeric_limits< unsigned short >::digits) +
|
|
(Bits <= std::numeric_limits< unsigned char >::digits)) );
|
|
};
|
|
|
|
template < int BitsIncludingSign >
|
|
struct int_exact_rank_helper { BOOST_STATIC_CONSTANT( int, rank = 0 ); };
|
|
template < int Bits >
|
|
struct uint_exact_rank_helper { BOOST_STATIC_CONSTANT( int, rank = 0 ); };
|
|
|
|
#define BOOST_PRIVATE_INT_EXACT_BUILDER(Type, Rank) \
|
|
template < > \
|
|
struct int_exact_rank_helper<std::numeric_limits< Type >::digits + 1> \
|
|
{ BOOST_STATIC_CONSTANT( int, rank = Rank ); }
|
|
#define BOOST_PRIVATE_UINT_EXACT_BUILDER(Type, Rank) \
|
|
template < > \
|
|
struct uint_exact_rank_helper<std::numeric_limits< Type >::digits> \
|
|
{ BOOST_STATIC_CONSTANT( int, rank = Rank ); }
|
|
|
|
#if defined(BOOST_HAS_LONG_LONG) && ((ULLONG_MAX > ULONG_MAX) || (ULONGLONG_MAX > ULONG_MAX))
|
|
BOOST_PRIVATE_INT_EXACT_BUILDER( long_long_type, 1 );
|
|
BOOST_PRIVATE_UINT_EXACT_BUILDER( ulong_long_type, 1 );
|
|
#elif defined(BOOST_HAS_MS_INT64) && (0xFFFFFFFFFFFFFFFFui64 > ULONG_MAX)
|
|
BOOST_PRIVATE_INT_EXACT_BUILDER( __int64, 1 );
|
|
BOOST_PRIVATE_UINT_EXACT_BUILDER( unsigned __int64, 1 );
|
|
#endif
|
|
#if ULONG_MAX > UINT_MAX
|
|
BOOST_PRIVATE_INT_EXACT_BUILDER( long, 2 );
|
|
BOOST_PRIVATE_UINT_EXACT_BUILDER( unsigned long, 2 );
|
|
#endif
|
|
#if UINT_MAX > USHRT_MAX
|
|
BOOST_PRIVATE_INT_EXACT_BUILDER( int, 3 );
|
|
BOOST_PRIVATE_UINT_EXACT_BUILDER( unsigned, 3 );
|
|
#endif
|
|
#if USHRT_MAX > UCHAR_MAX
|
|
BOOST_PRIVATE_INT_EXACT_BUILDER( short, 4 );
|
|
BOOST_PRIVATE_UINT_EXACT_BUILDER( unsigned short, 4 );
|
|
#endif
|
|
BOOST_PRIVATE_INT_EXACT_BUILDER( signed char, 5 );
|
|
BOOST_PRIVATE_UINT_EXACT_BUILDER( unsigned char, 5 );
|
|
|
|
#undef BOOST_PRIVATE_INT_EXACT_BUILDER
|
|
#undef BOOST_PRIVATE_UINT_EXACT_BUILDER
|
|
|
|
// map an extreme value to a category
|
|
template < intmax_t MaxValue >
|
|
struct int_max_rank_helper
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, rank = (MaxValue > 0) * (
|
|
#ifdef BOOST_HAS_LONG_LONG
|
|
(MaxValue <= integer_traits< long_long_type >::const_max) +
|
|
#elif defined(BOOST_HAS_MS_INT64)
|
|
(MaxValue <= integer_traits< __int64 >::const_max) +
|
|
#else
|
|
1 +
|
|
#endif
|
|
(MaxValue <= integer_traits< long >::const_max) +
|
|
(MaxValue <= integer_traits< int >::const_max) +
|
|
(MaxValue <= integer_traits< short >::const_max) +
|
|
(MaxValue <= integer_traits< signed char >::const_max)) );
|
|
};
|
|
|
|
template < intmax_t MinValue >
|
|
struct int_min_rank_helper
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, rank = (MinValue < 0) * (
|
|
#ifdef BOOST_HAS_LONG_LONG
|
|
(MinValue >= integer_traits< long_long_type >::const_min) +
|
|
#elif defined(BOOST_HAS_MS_INT64)
|
|
(MinValue >= integer_traits< __int64 >::const_min) +
|
|
#else
|
|
1 +
|
|
#endif
|
|
(MinValue >= integer_traits< long >::const_min) +
|
|
(MinValue >= integer_traits< int >::const_min) +
|
|
(MinValue >= integer_traits< short >::const_min) +
|
|
(MinValue >= integer_traits< signed char >::const_min)) );
|
|
};
|
|
|
|
template < uintmax_t Value >
|
|
struct uint_max_rank_helper
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, rank =
|
|
#ifdef BOOST_HAS_LONG_LONG
|
|
(Value <= integer_traits< ulong_long_type >::const_max) +
|
|
#elif defined(BOOST_HAS_MS_INT64)
|
|
(Value <= integer_traits< unsigned __int64 >::const_max) +
|
|
#else
|
|
1 +
|
|
#endif
|
|
(Value <= integer_traits< unsigned long >::const_max) +
|
|
(Value <= integer_traits< unsigned int >::const_max) +
|
|
(Value <= integer_traits< unsigned short >::const_max) +
|
|
(Value <= integer_traits< unsigned char >::const_max) );
|
|
};
|
|
|
|
// convert rank to type, Boost.MPL-style
|
|
template < int Rank, typename Signedness, class Enable = void >
|
|
struct integral_rank_to_type
|
|
{
|
|
BOOST_STATIC_CONSTANT( bool, is_specialized = false );
|
|
// No "signed" nor "type" here
|
|
};
|
|
|
|
template < int Rank >
|
|
struct integral_rank_to_type< Rank, signed, typename
|
|
enable_if_c<(lowest_integral_rank <= Rank) && (Rank <=
|
|
highest_integral_rank)>::type >
|
|
{
|
|
BOOST_STATIC_CONSTANT( bool, is_specialized = true );
|
|
BOOST_STATIC_CONSTANT( bool, is_signed = true );
|
|
typedef typename int_least_helper< Rank, signed >::least type;
|
|
};
|
|
|
|
template < int Rank >
|
|
struct integral_rank_to_type< Rank, unsigned, typename
|
|
enable_if_c<(lowest_integral_rank <= Rank) && (Rank <=
|
|
highest_integral_rank)>::type >
|
|
{
|
|
BOOST_STATIC_CONSTANT( bool, is_specialized = true );
|
|
BOOST_STATIC_CONSTANT( bool, is_signed = false );
|
|
typedef typename int_least_helper< Rank, unsigned >::least type;
|
|
};
|
|
|
|
} // namespace detail
|
|
|
|
// MPL-compatible integer-mapping class templates ------------------------//
|
|
|
|
// minimum number of bits
|
|
template < int Bits, typename Signedness >
|
|
struct sized_integral
|
|
{
|
|
BOOST_STATIC_CONSTANT( bool, is_specialized = false );
|
|
BOOST_STATIC_CONSTANT( int, bit_count = Bits );
|
|
};
|
|
|
|
template < int BitsIncludingSign >
|
|
struct sized_integral< BitsIncludingSign, signed >
|
|
: detail::integral_rank_to_type<
|
|
detail::int_rank_helper<BitsIncludingSign>::rank, signed >
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, bit_count = BitsIncludingSign );
|
|
};
|
|
|
|
template < int Bits >
|
|
struct sized_integral< Bits, unsigned >
|
|
: detail::integral_rank_to_type<
|
|
detail::uint_rank_helper<Bits>::rank, unsigned >
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, bit_count = Bits );
|
|
};
|
|
|
|
// exact number of bits
|
|
template < int Bits, typename Signedness >
|
|
struct exact_integral
|
|
{
|
|
BOOST_STATIC_CONSTANT( bool, is_specialized = false );
|
|
BOOST_STATIC_CONSTANT( int, bit_count = Bits );
|
|
};
|
|
|
|
template < int BitsIncludingSign >
|
|
struct exact_integral< BitsIncludingSign, signed >
|
|
: detail::integral_rank_to_type<
|
|
detail::int_exact_rank_helper<BitsIncludingSign>::rank, signed >
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, bit_count = BitsIncludingSign );
|
|
};
|
|
|
|
template < int Bits >
|
|
struct exact_integral< Bits, unsigned >
|
|
: detail::integral_rank_to_type<
|
|
detail::uint_exact_rank_helper<Bits>::rank, unsigned >
|
|
{
|
|
BOOST_STATIC_CONSTANT( int, bit_count = Bits );
|
|
};
|
|
|
|
// maximum supported (positive) value, signed
|
|
template < intmax_t MaxValue >
|
|
struct maximum_signed_integral
|
|
: detail::integral_rank_to_type<
|
|
detail::int_max_rank_helper<MaxValue>::rank, signed >
|
|
{
|
|
BOOST_STATIC_CONSTANT( intmax_t, bound = MaxValue );
|
|
};
|
|
|
|
// minimum supported (negative) value
|
|
template < intmax_t MinValue >
|
|
struct minimum_signed_integral
|
|
: detail::integral_rank_to_type<
|
|
detail::int_min_rank_helper<MinValue>::rank, signed >
|
|
{
|
|
BOOST_STATIC_CONSTANT( intmax_t, bound = MinValue );
|
|
};
|
|
|
|
// maximum supported (nonnegative) value, unsigned
|
|
template < uintmax_t Value >
|
|
struct maximum_unsigned_integral
|
|
: detail::integral_rank_to_type<
|
|
detail::uint_max_rank_helper<Value>::rank, unsigned >
|
|
{
|
|
BOOST_STATIC_CONSTANT( uintmax_t, bound = Value );
|
|
};
|
|
|
|
// integer templates specifying number of bits ---------------------------//
|
|
|
|
// signed
|
|
template< int Bits > // minimum bits (including sign) required
|
|
struct int_t
|
|
{
|
|
typedef typename sized_integral<Bits, signed>::type least;
|
|
typedef typename int_fast_t<least>::fast fast;
|
|
};
|
|
|
|
template< int Bits > // exact bits (including sign) desired
|
|
struct int_exact_t
|
|
{
|
|
typedef typename exact_integral<Bits, signed>::type exact;
|
|
};
|
|
|
|
// unsigned
|
|
template< int Bits > // minimum bits required
|
|
struct uint_t
|
|
{
|
|
typedef typename sized_integral<Bits, unsigned>::type least;
|
|
typedef typename int_fast_t<least>::fast fast;
|
|
// int_fast_t<> works correctly for unsigned too, in spite of the name.
|
|
};
|
|
|
|
template< int Bits > // exact bits desired
|
|
struct uint_exact_t
|
|
{
|
|
typedef typename exact_integral<Bits, unsigned>::type exact;
|
|
};
|
|
|
|
// integer templates specifying extreme value ----------------------------//
|
|
|
|
// signed
|
|
template< intmax_t MaxValue > // maximum value to require support
|
|
struct int_max_value_t
|
|
{
|
|
typedef typename maximum_signed_integral<MaxValue>::type least;
|
|
typedef typename int_fast_t<least>::fast fast;
|
|
};
|
|
|
|
template< intmax_t MinValue > // minimum value to require support
|
|
struct int_min_value_t
|
|
{
|
|
typedef typename minimum_signed_integral<MinValue>::type least;
|
|
typedef typename int_fast_t<least>::fast fast;
|
|
};
|
|
|
|
// unsigned
|
|
template< uintmax_t Value > // maximum value to require support
|
|
struct uint_value_t
|
|
{
|
|
typedef typename maximum_unsigned_integral<Value>::type least;
|
|
typedef typename int_fast_t<least>::fast fast;
|
|
};
|
|
|
|
|
|
} // namespace boost
|
|
|
|
#endif // BOOST_INTEGER_HPP
|