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Full merge from trunk at revision 41356 of entire boost-root tree.

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[SVN r41369]
This commit is contained in:
Beman Dawes
2007-11-25 18:07:19 +00:00
parent b59fe14895
commit 3cd8ea5b60
12 changed files with 283 additions and 94 deletions
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include/boost/functional/detail/container_fwd.hpp
+3 -3
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@@ -1,7 +1,7 @@
// Copyright Daniel James 2005-2006. Use, modification, and distribution are
// subject to 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)
// Copyright 2005-2007 Daniel James.
// 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)
#if !defined(BOOST_DETAIL_CONTAINER_FWD_HPP)
#define BOOST_DETAIL_CONTAINER_FWD_HPP
include/boost/functional/detail/float_functions.hpp
+3 -3
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@@ -1,7 +1,7 @@
// Copyright Daniel James 2005-2006. Use, modification, and distribution are
// subject to 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)
// Copyright 2005-2007 Daniel James.
// 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)
#if !defined(BOOST_FUNCTIONAL_DETAIL_FLOAT_FUNCTIONS_HPP)
#define BOOST_FUNCTIONAL_DETAIL_FLOAT_FUNCTIONS_HPP
include/boost/functional/detail/hash_float.hpp
+88 -27
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@@ -1,7 +1,7 @@
// Copyright Daniel James 2005-2006. Use, modification, and distribution are
// subject to 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)
// Copyright 2005-2007 Daniel James.
// 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)
// Based on Peter Dimov's proposal
// http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1756.pdf
@@ -15,24 +15,40 @@
#endif
#include <boost/functional/detail/float_functions.hpp>
#include <boost/integer/static_log2.hpp>
#include <boost/cstdint.hpp>
#include <boost/limits.hpp>
#include <boost/assert.hpp>
#include <errno.h>
// Don't use fpclassify or _fpclass for stlport.
#if !defined(__SGI_STL_PORT) && !defined(_STLPORT_VERSION)
# if defined(__GLIBCPP__) || defined(__GLIBCXX__)
// GNU libstdc++ 3
# if (defined(__USE_ISOC99) || defined(_GLIBCXX_USE_C99_MATH)) && \
!(defined(macintosh) || defined(__APPLE__) || defined(__APPLE_CC__))
# define BOOST_HASH_USE_FPCLASSIFY
# endif
# elif (defined(_YVALS) && !defined(__IBMCPP__)) || defined(_CPPLIB_VER)
// Dinkumware Library, on Visual C++
# if defined(BOOST_MSVC)
# define BOOST_HASH_USE_FPCLASS
# endif
// Select implementation for the current platform.
// Cygwn
#if defined(__CYGWIN__)
# if defined(__i386__) || defined(_M_IX86)
# define BOOST_HASH_USE_x86_BINARY_HASH
# endif
// STLport
#elif defined(__SGI_STL_PORT) || defined(_STLPORT_VERSION)
// _fpclass and fpclassify aren't good enough on STLport.
// GNU libstdc++ 3
#elif defined(__GLIBCPP__) || defined(__GLIBCXX__)
# if (defined(__USE_ISOC99) || defined(_GLIBCXX_USE_C99_MATH)) && \
!(defined(macintosh) || defined(__APPLE__) || defined(__APPLE_CC__))
# define BOOST_HASH_USE_FPCLASSIFY
# endif
// Dinkumware Library, on Visual C++
#elif (defined(_YVALS) && !defined(__IBMCPP__)) || defined(_CPPLIB_VER)
// Not using _fpclass because it causes a warning about a conversion
// from 'long double' to 'double'. Pity.
//
//# if defined(BOOST_MSVC)
//# define BOOST_HASH_USE_FPCLASS
//# endif
#endif
namespace boost
@@ -44,25 +60,69 @@ namespace boost
seed ^= value + (seed<<6) + (seed>>2);
}
// A simple, non-portable hash algorithm for x86.
#if defined(BOOST_HASH_USE_x86_BINARY_HASH)
inline std::size_t float_hash_impl(float v)
{
boost::uint32_t* ptr = (boost::uint32_t*)&v;
std::size_t seed = *ptr;
return seed;
}
inline std::size_t float_hash_impl(double v)
{
boost::uint32_t* ptr = (boost::uint32_t*)&v;
std::size_t seed = *ptr++;
hash_float_combine(seed, *ptr);
return seed;
}
inline std::size_t float_hash_impl(long double v)
{
boost::uint32_t* ptr = (boost::uint32_t*)&v;
std::size_t seed = *ptr++;
hash_float_combine(seed, *ptr++);
hash_float_combine(seed, *(boost::uint16_t*)ptr);
return seed;
}
#else
template <class T>
inline std::size_t float_hash_impl(T v)
{
int exp = 0;
errno = 0;
v = boost::hash_detail::call_frexp(v, &exp);
if(errno) return 0;
std::size_t seed = 0;
// A postive value is easier to hash, so combine the
// sign with the exponent.
if(v < 0) {
v = -v;
exp += std::numeric_limits<T>::max_exponent -
std::numeric_limits<T>::min_exponent;
}
// The result of frexp is always between 0.5 and 1, so its
// top bit will always be 1. Subtract by 0.5 to remove that.
v -= T(0.5);
v = boost::hash_detail::call_ldexp(v,
std::numeric_limits<std::size_t>::digits + 1);
std::size_t seed = static_cast<std::size_t>(v);
v -= seed;
// ceiling(digits(T) * log2(radix(T))/ digits(size_t)) - 1;
std::size_t const length
= (std::numeric_limits<T>::digits +
std::numeric_limits<int>::digits - 1)
/ std::numeric_limits<int>::digits;
= (std::numeric_limits<T>::digits *
boost::static_log2<std::numeric_limits<T>::radix>::value
- 1)
/ std::numeric_limits<std::size_t>::digits;
for(std::size_t i = 0; i < length; ++i)
for(std::size_t i = 0; i != length; ++i)
{
v = boost::hash_detail::call_ldexp(v, std::numeric_limits<int>::digits);
int const part = static_cast<int>(v);
v = boost::hash_detail::call_ldexp(v,
std::numeric_limits<std::size_t>::digits);
std::size_t part = static_cast<std::size_t>(v);
v -= part;
hash_float_combine(seed, part);
}
@@ -71,6 +131,7 @@ namespace boost
return seed;
}
#endif
template <class T>
inline std::size_t float_hash_value(T v)
@@ -114,7 +175,7 @@ namespace boost
return 0;
}
#else
return float_hash_impl(v);
return v == 0 ? 0 : float_hash_impl(v);
#endif
}
}