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-rw-r--r--boost/functional/hash/detail/hash_float.hpp271
1 files changed, 0 insertions, 271 deletions
diff --git a/boost/functional/hash/detail/hash_float.hpp b/boost/functional/hash/detail/hash_float.hpp
deleted file mode 100644
index 1816c57e9a..0000000000
--- a/boost/functional/hash/detail/hash_float.hpp
+++ /dev/null
@@ -1,271 +0,0 @@
-
-// Copyright 2005-2012 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_HASH_DETAIL_HASH_FLOAT_HEADER)
-#define BOOST_FUNCTIONAL_HASH_DETAIL_HASH_FLOAT_HEADER
-
-#include <boost/config.hpp>
-#if defined(BOOST_HAS_PRAGMA_ONCE)
-#pragma once
-#endif
-
-#include <boost/functional/hash/detail/float_functions.hpp>
-#include <boost/functional/hash/detail/limits.hpp>
-#include <boost/utility/enable_if.hpp>
-#include <boost/integer/static_log2.hpp>
-#include <boost/cstdint.hpp>
-#include <boost/assert.hpp>
-#include <boost/limits.hpp>
-#include <cstring>
-
-#if defined(BOOST_MSVC)
-#pragma warning(push)
-#if BOOST_MSVC >= 1400
-#pragma warning(disable:6294) // Ill-defined for-loop: initial condition does
- // not satisfy test. Loop body not executed
-#endif
-#endif
-
-// Can we use fpclassify?
-
-// STLport
-#if defined(__SGI_STL_PORT) || defined(_STLPORT_VERSION)
-#define BOOST_HASH_USE_FPCLASSIFY 0
-
-// 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 1
-# else
-# define BOOST_HASH_USE_FPCLASSIFY 0
-# endif
-
-// Everything else
-#else
-# define BOOST_HASH_USE_FPCLASSIFY 0
-#endif
-
-namespace boost
-{
- namespace hash_detail
- {
- inline void hash_float_combine(std::size_t& seed, std::size_t value)
- {
- seed ^= value + (seed<<6) + (seed>>2);
- }
-
- ////////////////////////////////////////////////////////////////////////
- // Binary hash function
- //
- // Only used for floats with known iec559 floats, and certain values in
- // numeric_limits
-
- inline std::size_t hash_binary(char* ptr, std::size_t length)
- {
- std::size_t seed = 0;
-
- if (length >= sizeof(std::size_t)) {
- std::memcpy(&seed, ptr, sizeof(std::size_t));
- length -= sizeof(std::size_t);
- ptr += sizeof(std::size_t);
-
- while(length >= sizeof(std::size_t)) {
- std::size_t buffer = 0;
- std::memcpy(&buffer, ptr, sizeof(std::size_t));
- hash_float_combine(seed, buffer);
- length -= sizeof(std::size_t);
- ptr += sizeof(std::size_t);
- }
- }
-
- if (length > 0) {
- std::size_t buffer = 0;
- std::memcpy(&buffer, ptr, length);
- hash_float_combine(seed, buffer);
- }
-
- return seed;
- }
-
- template <typename Float, unsigned digits, unsigned max_exponent>
- struct enable_binary_hash
- {
- BOOST_STATIC_CONSTANT(bool, value =
- std::numeric_limits<Float>::is_iec559 &&
- std::numeric_limits<Float>::digits == digits &&
- std::numeric_limits<Float>::radix == 2 &&
- std::numeric_limits<Float>::max_exponent == max_exponent);
- };
-
- template <typename Float>
- inline std::size_t float_hash_impl(Float v,
- BOOST_DEDUCED_TYPENAME boost::enable_if_c<
- enable_binary_hash<Float, 24, 128>::value,
- std::size_t>::type)
- {
- return hash_binary((char*) &v, 4);
- }
-
-
- template <typename Float>
- inline std::size_t float_hash_impl(Float v,
- BOOST_DEDUCED_TYPENAME boost::enable_if_c<
- enable_binary_hash<Float, 53, 1024>::value,
- std::size_t>::type)
- {
- return hash_binary((char*) &v, 8);
- }
-
- template <typename Float>
- inline std::size_t float_hash_impl(Float v,
- BOOST_DEDUCED_TYPENAME boost::enable_if_c<
- enable_binary_hash<Float, 64, 16384>::value,
- std::size_t>::type)
- {
- return hash_binary((char*) &v, 10);
- }
-
- template <typename Float>
- inline std::size_t float_hash_impl(Float v,
- BOOST_DEDUCED_TYPENAME boost::enable_if_c<
- enable_binary_hash<Float, 113, 16384>::value,
- std::size_t>::type)
- {
- return hash_binary((char*) &v, 16);
- }
-
- ////////////////////////////////////////////////////////////////////////
- // Portable hash function
- //
- // Used as a fallback when the binary hash function isn't supported.
-
- template <class T>
- inline std::size_t float_hash_impl2(T v)
- {
- boost::hash_detail::call_frexp<T> frexp;
- boost::hash_detail::call_ldexp<T> ldexp;
-
- int exp = 0;
-
- v = frexp(v, &exp);
-
- // A postive value is easier to hash, so combine the
- // sign with the exponent and use the absolute value.
- if(v < 0) {
- v = -v;
- exp += limits<T>::max_exponent -
- limits<T>::min_exponent;
- }
-
- v = ldexp(v, limits<std::size_t>::digits);
- std::size_t seed = static_cast<std::size_t>(v);
- v -= static_cast<T>(seed);
-
- // ceiling(digits(T) * log2(radix(T))/ digits(size_t)) - 1;
- std::size_t const length
- = (limits<T>::digits *
- boost::static_log2<limits<T>::radix>::value
- + limits<std::size_t>::digits - 1)
- / limits<std::size_t>::digits;
-
- for(std::size_t i = 0; i != length; ++i)
- {
- v = ldexp(v, limits<std::size_t>::digits);
- std::size_t part = static_cast<std::size_t>(v);
- v -= static_cast<T>(part);
- hash_float_combine(seed, part);
- }
-
- hash_float_combine(seed, static_cast<std::size_t>(exp));
-
- return seed;
- }
-
-#if !defined(BOOST_HASH_DETAIL_TEST_WITHOUT_GENERIC)
- template <class T>
- inline std::size_t float_hash_impl(T v, ...)
- {
- typedef BOOST_DEDUCED_TYPENAME select_hash_type<T>::type type;
- return float_hash_impl2(static_cast<type>(v));
- }
-#endif
- }
-}
-
-#if BOOST_HASH_USE_FPCLASSIFY
-
-#include <boost/config/no_tr1/cmath.hpp>
-
-namespace boost
-{
- namespace hash_detail
- {
- template <class T>
- inline std::size_t float_hash_value(T v)
- {
-#if defined(fpclassify)
- switch (fpclassify(v))
-#elif BOOST_HASH_CONFORMANT_FLOATS
- switch (std::fpclassify(v))
-#else
- using namespace std;
- switch (fpclassify(v))
-#endif
- {
- case FP_ZERO:
- return 0;
- case FP_INFINITE:
- return (std::size_t)(v > 0 ? -1 : -2);
- case FP_NAN:
- return (std::size_t)(-3);
- case FP_NORMAL:
- case FP_SUBNORMAL:
- return float_hash_impl(v, 0);
- default:
- BOOST_ASSERT(0);
- return 0;
- }
- }
- }
-}
-
-#else // !BOOST_HASH_USE_FPCLASSIFY
-
-namespace boost
-{
- namespace hash_detail
- {
- template <class T>
- inline bool is_zero(T v)
- {
-#if !defined(__GNUC__) && !defined(__clang__)
- return v == 0;
-#else
- // GCC's '-Wfloat-equal' will complain about comparing
- // v to 0, but because it disables warnings for system
- // headers it won't complain if you use std::equal_to to
- // compare with 0. Resulting in this silliness:
- return std::equal_to<T>()(v, 0);
-#endif
- }
-
- template <class T>
- inline std::size_t float_hash_value(T v)
- {
- return boost::hash_detail::is_zero(v) ? 0 : float_hash_impl(v, 0);
- }
- }
-}
-
-#endif // BOOST_HASH_USE_FPCLASSIFY
-
-#undef BOOST_HASH_USE_FPCLASSIFY
-
-#if defined(BOOST_MSVC)
-#pragma warning(pop)
-#endif
-
-#endif