1 files changed, 106 insertions, 0 deletions
diff --git a/libstdc++-v3/src/hash.cc b/libstdc++-v3/src/hash.cc
new file mode 100644
index 00000000000..e778e2bf366
--- /dev/null
+++ b/libstdc++-v3/src/hash.cc
@@ -0,0 +1,106 @@
+//  std::hash and std::tr1::hash definitions -*- C++ -*-
+
+// Copyright (C) 2007 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this library; see the file COPYING.  If not, write to
+// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+// Boston, MA 02110-1301, USA.
+
+// As a special exception, you may use this file as part of a free software
+// library without restriction.  Specifically, if other files instantiate
+// templates or use macros or inline functions from this file, or you compile
+// this file and link it with other files to produce an executable, this
+// file does not by itself cause the resulting executable to be covered by
+// the GNU General Public License.  This exception does not however
+// invalidate any other reasons why the executable file might be covered by
+// the GNU General Public License.
+
+#include <cstddef>
+#include <string>
+#include <cmath>
+
+#ifdef __GXX_EXPERIMENTAL_CXX0X__
+#include <functional>
+#  define _GLIBCXX_BEGIN_NAMESPACE_TR1 
+#  define _GLIBCXX_END_NAMESPACE_TR1 
+#else
+#include <tr1/functional>
+#  define _GLIBCXX_BEGIN_NAMESPACE_TR1 namespace tr1 {
+#  define _GLIBCXX_END_NAMESPACE_TR1 }
+#endif
+
+namespace std
+{
+_GLIBCXX_BEGIN_NAMESPACE_TR1
+
+  // For long double, careful with random padding bits (e.g., on x86,
+  // 10 bytes -> 12 bytes) and resort to frexp.
+  template<>
+    size_t
+    hash<long double>::operator()(long double __val) const
+    {
+      size_t __result = 0;
+
+      int __exponent;
+      __val = std::frexp(__val, &__exponent);
+      __val = __val < 0.0l ? -(__val + 0.5l) : __val;
+
+      const long double __mult =
+      __gnu_cxx::__numeric_traits<size_t>::__max + 1.0l;
+      __val *= __mult;
+
+      // Try to use all the bits of the mantissa (really necessary only
+      // on 32-bit targets, at least for 80-bit floating point formats).
+      const size_t __hibits = (size_t)__val;
+      __val = (__val - (long double)__hibits) * __mult;
+
+      const size_t __coeff =
+	__gnu_cxx::__numeric_traits<size_t>::__max / __LDBL_MAX_EXP__;
+
+      __result = __hibits + (size_t)__val + __coeff * __exponent;
+
+      return __result;
+    };
+
+  template<>
+    size_t
+    hash<string>::operator()(string __s) const
+    { return _Fnv_hash<>::hash(__s.data(), __s.length()); }
+
+  template<>
+    size_t
+    hash<const string&>::operator()(const string& __s) const
+    { return _Fnv_hash<>::hash(__s.data(), __s.length()); }
+
+#ifdef _GLIBCXX_USE_WCHAR_T
+  template<>
+    size_t
+    hash<wstring>::operator()(wstring __s) const
+    {
+      const char* __p = reinterpret_cast<const char*>(__s.data());
+      return _Fnv_hash<>::hash(__p, __s.length() * sizeof(wchar_t));
+    }
+
+  template<>
+    size_t
+    hash<const wstring&>::operator()(const wstring& __s) const
+    {
+      const char* __p = reinterpret_cast<const char*>(__s.data());
+      return _Fnv_hash<>::hash(__p, __s.length() * sizeof(wchar_t));
+    }
+#endif
+
+_GLIBCXX_END_NAMESPACE_TR1
+}