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Add support for long long to Boost.Hash.

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[SVN r34202]
This commit is contained in:
Daniel James
2006-06-06 20:13:33 +00:00
parent 1d61057ee9
commit e143c22dbd
1 changed files with 77 additions and 0 deletions
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77
include/boost/functional/hash/hash.hpp
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@@ -10,6 +10,10 @@
#if !defined(BOOST_FUNCTIONAL_HASH_HASH_HPP)
#define BOOST_FUNCTIONAL_HASH_HASH_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif
#include <boost/functional/hash_fwd.hpp>
#include <functional>
#include <boost/functional/detail/hash_float.hpp>
@@ -41,6 +45,11 @@ namespace boost
std::size_t hash_value(long);
std::size_t hash_value(unsigned long);
#if defined(BOOST_HAS_LONG_LONG)
std::size_t hash_value(long long);
std::size_t hash_value(unsigned long long);
#endif
#if !BOOST_WORKAROUND(__DMC__, BOOST_TESTED_AT(0x847))
template <class T> std::size_t hash_value(T* const&);
#else
@@ -79,8 +88,55 @@ namespace boost
template <class K, class T, class C, class A>
std::size_t hash_value(std::multimap<K, T, C, A> const& v);
template <class T>
std::size_t hash_value(std::complex<T> const&);
// Implementation
namespace hash_detail
{
template <class T>
inline size_t hash_value_signed(T val)
{
const int size_t_bits = std::numeric_limits<size_t>::digits;
// ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1
const int length = (std::numeric_limits<T>::digits - 1)
/ size_t_bits;
size_t seed = 0;
T positive = val < 0 ? -1 - val : val;
// Hopefully, this loop can be unrolled.
for(unsigned int i = length * size_t_bits; i > 0; i -= size_t_bits)
{
seed ^= (size_t) (positive >> i) + (seed<<6) + (seed>>2);
}
seed ^= (size_t) val + (seed<<6) + (seed>>2);
return seed;
}
template <class T>
inline size_t hash_value_unsigned(T val)
{
const int size_t_bits = std::numeric_limits<size_t>::digits;
// ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1
const int length = (std::numeric_limits<T>::digits - 1)
/ size_t_bits;
size_t seed = 0;
// Hopefully, this loop can be unrolled.
for(unsigned int i = length * size_t_bits; i > 0; i -= size_t_bits)
{
seed ^= (size_t) (val >> i) + (seed<<6) + (seed>>2);
}
seed ^= (size_t) val + (seed<<6) + (seed>>2);
return seed;
}
}
#if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551))
inline std::size_t hash_value(bool v)
{
@@ -108,6 +164,18 @@ namespace boost
return static_cast<std::size_t>(v);
}
#if defined(BOOST_HAS_LONG_LONG)
inline std::size_t hash_value(long long v)
{
return hash_detail::hash_value_signed(v);
}
inline std::size_t hash_value(unsigned long long v)
{
return hash_detail::hash_value_unsigned(v);
}
#endif
// Implementation by Alberto Barbati and Dave Harris.
#if !BOOST_WORKAROUND(__DMC__, BOOST_TESTED_AT(0x847))
template <class T> std::size_t hash_value(T* const& v)
@@ -266,6 +334,15 @@ namespace boost
return hash_range(v.begin(), v.end());
}
template <class K, class T, class C, class A>
std::size_t hash_value(std::complex<T> const& v)
{
boost::hash<T> hasher;
std::size_t seed = hasher(v.imag());
seed ^= hasher(v.real()) + (seed<<6) + (seed>>2);
return seed;
}
//
// boost::hash
//