Add boost subset as an implementation detail

1 files changed, 56 insertions, 0 deletions

diff --git a/cutl/details/boost/functional/hash/detail/hash_float_x86.hpp b/cutl/details/boost/functional/hash/detail/hash_float_x86.hpp
new file mode 100644
index 0000000..6a70556
--- /dev/null
+++ b/cutl/details/boost/functional/hash/detail/hash_float_x86.hpp
@@ -0,0 +1,56 @@
+
+// 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