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+
+// 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)
+
+// A non-portable hash function form non-zero floats on x86.
+//
+// Even if you're on an x86 platform, this might not work if their floating
+// point isn't set up as this expects. So this should only be used if it's
+// absolutely certain that it will work.
+
+#if !defined(BOOST_FUNCTIONAL_HASH_DETAIL_HASH_FLOAT_X86_HEADER)
+#define BOOST_FUNCTIONAL_HASH_DETAIL_HASH_FLOAT_X86_HEADER
+
+#include <cutl/details/boost/cstdint.hpp>
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+namespace cutl_details_boost
+{
+ namespace hash_detail
+ {
+ inline void hash_float_combine(std::size_t& seed, std::size_t value)
+ {
+ seed ^= value + (seed<<6) + (seed>>2);
+ }
+
+ inline std::size_t float_hash_impl(float v)
+ {
+ cutl_details_boost::uint32_t* ptr = (cutl_details_boost::uint32_t*)&v;
+ std::size_t seed = *ptr;
+ return seed;
+ }
+
+ inline std::size_t float_hash_impl(double v)
+ {
+ cutl_details_boost::uint32_t* ptr = (cutl_details_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)
+ {
+ cutl_details_boost::uint32_t* ptr = (cutl_details_boost::uint32_t*)&v;
+ std::size_t seed = *ptr++;
+ hash_float_combine(seed, *ptr++);
+ hash_float_combine(seed, *(cutl_details_boost::uint16_t*)ptr);
+ return seed;
+ }
+ }
+}
+
+#endif