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boost_container_hash/include/boost/container_hash/hash.hpp
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// Copyright 2005-2014 Daniel James.
// Copyright 2021 Peter Dimov.
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
// Based on Peter Dimov's proposal
// http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1756.pdf
// issue 6.18.
//
// This also contains public domain code from MurmurHash. From the
// MurmurHash header:
// MurmurHash3 was written by Austin Appleby, and is placed in the public
// domain. The author hereby disclaims copyright to this source code.
#if !defined(BOOST_FUNCTIONAL_HASH_HASH_HPP)
#define BOOST_FUNCTIONAL_HASH_HASH_HPP
#include <boost/container_hash/hash_fwd.hpp>
#include <boost/container_hash/detail/hash_float.hpp>
#include <boost/container_hash/detail/is_range.hpp>
#include <boost/container_hash/detail/is_contiguous_range.hpp>
#include <boost/container_hash/detail/is_unordered_range.hpp>
#include <boost/type_traits/is_enum.hpp>
#include <boost/type_traits/is_integral.hpp>
#include <boost/type_traits/is_floating_point.hpp>
#include <boost/type_traits/make_unsigned.hpp>
#include <boost/core/enable_if.hpp>
#include <boost/limits.hpp>
#include <boost/cstdint.hpp>
#include <iterator>
#include <string>
#include <climits>
#if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
#include <typeindex>
#endif
#if !defined(BOOST_NO_CXX11_HDR_SYSTEM_ERROR)
#include <system_error>
#endif
#if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
#include <string_view>
#endif
#if !defined(BOOST_NO_CXX17_HDR_OPTIONAL)
#include <optional>
#endif
#if !defined(BOOST_NO_CXX17_HDR_VARIANT)
#include <variant>
#endif
#if defined(BOOST_MSVC)
#pragma warning(push)
#endif
#if defined(_MSC_VER)
# define BOOST_FUNCTIONAL_HASH_ROTL32(x, r) _rotl(x,r)
#else
# define BOOST_FUNCTIONAL_HASH_ROTL32(x, r) (x << r) | (x >> (32 - r))
#endif
namespace boost
{
// hash_value
// integral types
namespace hash_detail
{
template<class T, bool bigger_than_size_t, bool size_t_64> struct hash_integral_impl;
template<class T, bool size_t_64> struct hash_integral_impl<T, false, size_t_64>
{
static std::size_t fn( T v )
{
return static_cast<std::size_t>( v );
}
};
template<class T> struct hash_integral_impl<T, true, false>
{
static std::size_t fn( T v )
{
// 4294967291 = 2^32-5, biggest prime under 2^32
return static_cast<std::size_t>( static_cast<typename boost::make_unsigned<T>::type>( v ) % 4294967291 );
}
};
template<class T> struct hash_integral_impl<T, true, true>
{
static std::size_t fn( T v )
{
// 18446744073709551557ULL = 2^64-59, biggest prime under 2^64
// we have to use boost::uint64_t( -59 ), because g++ warns in C++03 mode
return static_cast<std::size_t>( static_cast<typename boost::make_unsigned<T>::type>( v ) % static_cast<boost::uint64_t>( -59 ) );
}
};
} // namespace hash_detail
template <typename T>
typename boost::enable_if<boost::is_integral<T>, std::size_t>::type
hash_value( T v )
{
return hash_detail::hash_integral_impl<T, (sizeof(T) > sizeof(std::size_t)), (sizeof(std::size_t) * CHAR_BIT >= 64)>::fn( v );
}
// enumeration types
template <typename T>
typename boost::enable_if<boost::is_enum<T>, std::size_t>::type
hash_value( T v )
{
return static_cast<std::size_t>( v );
}
// floating point types
template <typename T>
typename boost::enable_if<boost::is_floating_point<T>, std::size_t>::type
hash_value( T v )
{
return boost::hash_detail::float_hash_value( v );
}
// pointer types
// Implementation by Alberto Barbati and Dave Harris.
template <class T> std::size_t hash_value( T* const& v )
{
std::size_t x = static_cast<std::size_t>(
reinterpret_cast<boost::uintptr_t>(v));
return x + (x >> 3);
}
// array types
template<class T, std::size_t N>
inline std::size_t hash_value( T const (&x)[ N ] )
{
return boost::hash_range( x, x + N );
}
template<class T, std::size_t N>
inline std::size_t hash_value( T (&x)[ N ] )
{
return boost::hash_range( x, x + N );
}
// ranges (list, set, deque...)
template <typename T>
typename boost::enable_if_c<hash_detail::is_range<T>::value && !hash_detail::is_contiguous_range<T>::value && !hash_detail::is_unordered_range<T>::value, std::size_t>::type
hash_value( T const& v )
{
return boost::hash_range( v.begin(), v.end() );
}
// contiguous ranges (string, vector, array)
template <typename T>
typename boost::enable_if<hash_detail::is_contiguous_range<T>, std::size_t>::type
hash_value( T const& v )
{
return boost::hash_range( v.data(), v.data() + v.size() );
}
// unordered ranges (unordered_set, unordered_map)
template <typename T>
typename boost::enable_if<hash_detail::is_unordered_range<T>, std::size_t>::type
hash_value( T const& v )
{
return boost::hash_unordered_range( v.begin(), v.end() );
}
#if defined(BOOST_MSVC) && BOOST_MSVC >= 1910 && BOOST_MSVC < 1920 && BOOST_CXX_VERSION >= 201700L
// resolve ambiguity with unconstrained stdext::hash_value in <xhash> :-/
template<template<class...> class L, class... T>
typename boost::enable_if_c<hash_detail::is_range<L<T...>>::value && !hash_detail::is_contiguous_range<L<T...>>::value && !hash_detail::is_unordered_range<L<T...>>::value, std::size_t>::type
hash_value( L<T...> const& v )
{
return boost::hash_range( v.begin(), v.end() );
}
// contiguous ranges (string, vector, array)
template<template<class...> class L, class... T>
typename boost::enable_if<hash_detail::is_contiguous_range<L<T...>>, std::size_t>::type
hash_value( L<T...> const& v )
{
return boost::hash_range( v.data(), v.data() + v.size() );
}
template<template<class, std::size_t> class L, class T, std::size_t N>
typename boost::enable_if<hash_detail::is_contiguous_range<L<T, N>>, std::size_t>::type
hash_value( L<T, N> const& v )
{
return boost::hash_range( v.data(), v.data() + v.size() );
}
// unordered ranges (unordered_set, unordered_map)
template<template<class...> class L, class... T>
typename boost::enable_if<hash_detail::is_unordered_range<L<T...>>, std::size_t>::type
hash_value( L<T...> const& v )
{
return boost::hash_unordered_range( v.begin(), v.end() );
}
#endif
// std::type_index
#if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
inline std::size_t hash_value( std::type_index const& v )
{
return v.hash_code();
}
#endif
// std::error_code, std::error_condition
#if !defined(BOOST_NO_CXX11_HDR_SYSTEM_ERROR)
inline std::size_t hash_value( std::error_code const& v )
{
std::size_t seed = 0;
boost::hash_combine( seed, v.value() );
boost::hash_combine( seed, &v.category() );
return seed;
}
inline std::size_t hash_value( std::error_condition const& v )
{
std::size_t seed = 0;
boost::hash_combine( seed, v.value() );
boost::hash_combine( seed, &v.category() );
return seed;
}
#endif
// std::optional
#if !defined(BOOST_NO_CXX17_HDR_OPTIONAL)
template <typename T>
std::size_t hash_value( std::optional<T> const& v )
{
if( !v )
{
// Arbitray value for empty optional.
return 0x12345678;
}
else
{
return boost::hash<T>()(*v);
}
}
#endif
// std::variant
#if !defined(BOOST_NO_CXX17_HDR_VARIANT)
inline std::size_t hash_value( std::monostate )
{
return 0x87654321;
}
template <typename... Types>
std::size_t hash_value( std::variant<Types...> const& v )
{
std::size_t seed = 0;
hash_combine( seed, v.index() );
std::visit( [&seed](auto&& x) { hash_combine(seed, x); }, v );
return seed;
}
#endif
// hash_combine
namespace hash_detail
{
template<int Bits> struct hash_combine_impl
{
template <typename SizeT>
inline static SizeT fn(SizeT seed, SizeT value)
{
seed ^= value + 0x9e3779b9 + (seed<<6) + (seed>>2);
return seed;
}
};
template<> struct hash_combine_impl<32>
{
inline static boost::uint32_t fn(boost::uint32_t h1, boost::uint32_t k1)
{
const boost::uint32_t c1 = 0xcc9e2d51;
const boost::uint32_t c2 = 0x1b873593;
k1 *= c1;
k1 = BOOST_FUNCTIONAL_HASH_ROTL32(k1,15);
k1 *= c2;
h1 ^= k1;
h1 = BOOST_FUNCTIONAL_HASH_ROTL32(h1,13);
h1 = h1*5+0xe6546b64;
return h1;
}
};
template<> struct hash_combine_impl<64>
{
inline static boost::uint64_t fn(boost::uint64_t h, boost::uint64_t k)
{
const boost::uint64_t m = (boost::uint64_t(0xc6a4a793) << 32) + 0x5bd1e995;
const int r = 47;
k *= m;
k ^= k >> r;
k *= m;
h ^= k;
h *= m;
// Completely arbitrary number, to prevent 0's
// from hashing to 0.
h += 0xe6546b64;
return h;
}
};
}
#if defined(BOOST_MSVC)
#pragma warning(push)
#if BOOST_MSVC <= 1400
#pragma warning(disable:4267) // 'argument' : conversion from 'size_t' to
// 'unsigned int', possible loss of data
// A misguided attempt to detect 64-bit
// incompatability.
#endif
#endif
template <class T>
inline void hash_combine(std::size_t& seed, T const& v)
{
boost::hash<T> hasher;
seed = boost::hash_detail::hash_combine_impl<sizeof(std::size_t) * CHAR_BIT>::fn(seed, hasher(v));
}
#if defined(BOOST_MSVC)
#pragma warning(pop)
#endif
template <class It>
inline std::size_t hash_range(It first, It last)
{
std::size_t seed = 0;
for(; first != last; ++first)
{
hash_combine<typename std::iterator_traits<It>::value_type>(seed, *first);
}
return seed;
}
template <class It>
inline void hash_range(std::size_t& seed, It first, It last)
{
for(; first != last; ++first)
{
hash_combine<typename std::iterator_traits<It>::value_type>(seed, *first);
}
}
#if BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x551))
template <class T>
inline std::size_t hash_range(T* first, T* last)
{
std::size_t seed = 0;
for(; first != last; ++first)
{
boost::hash<T> hasher;
seed ^= hasher(*first) + 0x9e3779b9 + (seed<<6) + (seed>>2);
}
return seed;
}
template <class T>
inline void hash_range(std::size_t& seed, T* first, T* last)
{
for(; first != last; ++first)
{
boost::hash<T> hasher;
seed ^= hasher(*first) + 0x9e3779b9 + (seed<<6) + (seed>>2);
}
}
#endif
//
// boost::hash
//
namespace hash_detail
{
template <typename T>
struct hash_base
{
typedef T argument_type;
typedef std::size_t result_type;
};
}
// Define the specializations required by the standard. The general purpose
// boost::hash is defined later in extensions.hpp if
// BOOST_HASH_NO_EXTENSIONS is not defined.
// BOOST_HASH_SPECIALIZE - define a specialization for a type which is
// passed by copy.
//
// BOOST_HASH_SPECIALIZE_REF - define a specialization for a type which is
// passed by const reference.
//
// These are undefined later.
#define BOOST_HASH_SPECIALIZE(type) \
template <> struct hash<type> \
: public boost::hash_detail::hash_base<type> \
{ \
std::size_t operator()(type v) const \
{ \
return boost::hash_value(v); \
} \
};
#define BOOST_HASH_SPECIALIZE_REF(type) \
template <> struct hash<type> \
: public boost::hash_detail::hash_base<type> \
{ \
std::size_t operator()(type const& v) const \
{ \
return boost::hash_value(v); \
} \
};
#define BOOST_HASH_SPECIALIZE_TEMPLATE_REF(type) \
struct hash<type> \
: public boost::hash_detail::hash_base<type> \
{ \
std::size_t operator()(type const& v) const \
{ \
return boost::hash_value(v); \
} \
};
BOOST_HASH_SPECIALIZE(bool)
BOOST_HASH_SPECIALIZE(char)
BOOST_HASH_SPECIALIZE(signed char)
BOOST_HASH_SPECIALIZE(unsigned char)
#if !defined(BOOST_NO_INTRINSIC_WCHAR_T)
BOOST_HASH_SPECIALIZE(wchar_t)
#endif
#if !defined(BOOST_NO_CXX11_CHAR16_T)
BOOST_HASH_SPECIALIZE(char16_t)
#endif
#if !defined(BOOST_NO_CXX11_CHAR32_T)
BOOST_HASH_SPECIALIZE(char32_t)
#endif
BOOST_HASH_SPECIALIZE(short)
BOOST_HASH_SPECIALIZE(unsigned short)
BOOST_HASH_SPECIALIZE(int)
BOOST_HASH_SPECIALIZE(unsigned int)
BOOST_HASH_SPECIALIZE(long)
BOOST_HASH_SPECIALIZE(unsigned long)
BOOST_HASH_SPECIALIZE(float)
BOOST_HASH_SPECIALIZE(double)
BOOST_HASH_SPECIALIZE(long double)
BOOST_HASH_SPECIALIZE_REF(std::string)
#if !defined(BOOST_NO_STD_WSTRING) && !defined(BOOST_NO_INTRINSIC_WCHAR_T)
BOOST_HASH_SPECIALIZE_REF(std::wstring)
#endif
#if !defined(BOOST_NO_CXX11_CHAR16_T)
BOOST_HASH_SPECIALIZE_REF(std::basic_string<char16_t>)
#endif
#if !defined(BOOST_NO_CXX11_CHAR32_T)
BOOST_HASH_SPECIALIZE_REF(std::basic_string<char32_t>)
#endif
#if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
BOOST_HASH_SPECIALIZE_REF(std::string_view)
# if !defined(BOOST_NO_STD_WSTRING) && !defined(BOOST_NO_INTRINSIC_WCHAR_T)
BOOST_HASH_SPECIALIZE_REF(std::wstring_view)
# endif
# if !defined(BOOST_NO_CXX11_CHAR16_T)
BOOST_HASH_SPECIALIZE_REF(std::basic_string_view<char16_t>)
# endif
# if !defined(BOOST_NO_CXX11_CHAR32_T)
BOOST_HASH_SPECIALIZE_REF(std::basic_string_view<char32_t>)
# endif
#endif
#if !defined(BOOST_NO_LONG_LONG)
BOOST_HASH_SPECIALIZE(boost::long_long_type)
BOOST_HASH_SPECIALIZE(boost::ulong_long_type)
#endif
#if defined(BOOST_HAS_INT128)
BOOST_HASH_SPECIALIZE(boost::int128_type)
BOOST_HASH_SPECIALIZE(boost::uint128_type)
#endif
#if !defined(BOOST_NO_CXX17_HDR_OPTIONAL)
template <typename T>
BOOST_HASH_SPECIALIZE_TEMPLATE_REF(std::optional<T>)
#endif
#if !defined(BOOST_NO_CXX17_HDR_VARIANT)
template <typename... T>
BOOST_HASH_SPECIALIZE_TEMPLATE_REF(std::variant<T...>)
BOOST_HASH_SPECIALIZE(std::monostate)
#endif
#if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
BOOST_HASH_SPECIALIZE(std::type_index)
#endif
#undef BOOST_HASH_SPECIALIZE
#undef BOOST_HASH_SPECIALIZE_REF
#undef BOOST_HASH_SPECIALIZE_TEMPLATE_REF
// Specializing boost::hash for pointers.
template <class T>
struct hash<T*>
: public boost::hash_detail::hash_base<T*>
{
std::size_t operator()(T* v) const
{
return boost::hash_value(v);
}
};
}
#undef BOOST_FUNCTIONAL_HASH_ROTL32
#if defined(BOOST_MSVC)
#pragma warning(pop)
#endif
#endif // BOOST_FUNCTIONAL_HASH_HASH_HPP
// Include this outside of the include guards in case the file is included
// twice - once with BOOST_HASH_NO_EXTENSIONS defined, and then with it
// undefined.
#if !defined(BOOST_HASH_NO_EXTENSIONS) \
&& !defined(BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP)
#include <boost/container_hash/extensions.hpp>
#endif