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Diffstat (limited to '3rdParty/Boost/src/boost/functional/hash/detail/hash_float.hpp')
-rw-r--r--3rdParty/Boost/src/boost/functional/hash/detail/hash_float.hpp197
1 files changed, 197 insertions, 0 deletions
diff --git a/3rdParty/Boost/src/boost/functional/hash/detail/hash_float.hpp b/3rdParty/Boost/src/boost/functional/hash/detail/hash_float.hpp
new file mode 100644
index 0000000..5d5ac34
--- /dev/null
+++ b/3rdParty/Boost/src/boost/functional/hash/detail/hash_float.hpp
@@ -0,0 +1,197 @@
+
+// Copyright 2005-2009 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
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+#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
+
+#include <boost/functional/hash/detail/float_functions.hpp>
+#include <boost/integer/static_log2.hpp>
+#include <boost/cstdint.hpp>
+#include <boost/limits.hpp>
+#include <boost/assert.hpp>
+
+// 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)
+// 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 is only available for double.
+
+#endif
+
+// On OpenBSD, numeric_limits is not reliable for long doubles, but
+// the macros defined in <float.h> are.
+
+#if defined(__OpenBSD__)
+#include <float.h>
+#endif
+
+namespace boost
+{
+ namespace hash_detail
+ {
+ template <class T>
+ struct limits : std::numeric_limits<T> {};
+
+#if defined(__OpenBSD__)
+ template <>
+ struct limits<long double>
+ : std::numeric_limits<long double>
+ {
+ static long double epsilon() {
+ return LDBL_EPSILON;
+ }
+
+ static long double (max)() {
+ return LDBL_MAX;
+ }
+
+ static long double (min)() {
+ return LDBL_MIN;
+ }
+
+ BOOST_STATIC_CONSTANT(int, digits = LDBL_MANT_DIG);
+ BOOST_STATIC_CONSTANT(int, max_exponent = LDBL_MAX_EXP);
+ BOOST_STATIC_CONSTANT(int, min_exponent = LDBL_MIN_EXP);
+ };
+#endif // __OpenBSD__
+
+ inline void hash_float_combine(std::size_t& seed, std::size_t value)
+ {
+ 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;
+
+ v = boost::hash_detail::call_frexp(v, &exp);
+
+ // A postive value is easier to hash, so combine the
+ // sign with the exponent.
+ if(v < 0) {
+ v = -v;
+ exp += limits<T>::max_exponent -
+ 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,
+ 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
+ = (limits<T>::digits *
+ boost::static_log2<limits<T>::radix>::value - 1)
+ / limits<std::size_t>::digits;
+
+ for(std::size_t i = 0; i != length; ++i)
+ {
+ v = boost::hash_detail::call_ldexp(v,
+ limits<std::size_t>::digits);
+ std::size_t part = static_cast<std::size_t>(v);
+ v -= part;
+ hash_float_combine(seed, part);
+ }
+
+ hash_float_combine(seed, exp);
+
+ return seed;
+ }
+#endif
+
+ template <class T>
+ inline std::size_t float_hash_value(T v)
+ {
+#if defined(BOOST_HASH_USE_FPCLASSIFY)
+ using namespace std;
+ switch (fpclassify(v)) {
+ 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);
+ default:
+ BOOST_ASSERT(0);
+ return 0;
+ }
+#else
+ return v == 0 ? 0 : float_hash_impl(v);
+#endif
+ }
+ }
+}
+
+#if defined(BOOST_MSVC)
+#pragma warning(pop)
+#endif
+
+#endif