aboutsummaryrefslogtreecommitdiffstats
path: root/gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp
diff options
context:
space:
mode:
Diffstat (limited to 'gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp')
-rw-r--r--gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp107
1 files changed, 107 insertions, 0 deletions
diff --git a/gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp b/gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp
new file mode 100644
index 000000000..936abbee1
--- /dev/null
+++ b/gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp
@@ -0,0 +1,107 @@
+// -*- C++ -*-
+
+// Copyright (C) 2005, 2006, 2009 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 3, 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.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+// <http://www.gnu.org/licenses/>.
+
+// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
+
+// Permission to use, copy, modify, sell, and distribute this software
+// is hereby granted without fee, provided that the above copyright
+// notice appears in all copies, and that both that copyright notice
+// and this permission notice appear in supporting documentation. None
+// of the above authors, nor IBM Haifa Research Laboratories, make any
+// representation about the suitability of this software for any
+// purpose. It is provided "as is" without express or implied
+// warranty.
+
+/**
+ * @file mask_based_range_hashing.hpp
+ * Contains a range hashing policy base.
+ */
+
+#ifndef PB_DS_MASK_BASED_RANGE_HASHING_HPP
+#define PB_DS_MASK_BASED_RANGE_HASHING_HPP
+
+namespace __gnu_pbds
+{
+ namespace detail
+ {
+#define PB_DS_CLASS_T_DEC template<typename Size_Type>
+#define PB_DS_CLASS_C_DEC mask_based_range_hashing<Size_Type>
+
+ template<typename Size_Type>
+ class mask_based_range_hashing
+ {
+ protected:
+ typedef Size_Type size_type;
+
+ void
+ swap(mask_based_range_hashing& other)
+ { std::swap(m_mask, other.m_mask); }
+
+ void
+ notify_resized(size_type size);
+
+ inline size_type
+ range_hash(size_type hash) const
+ { return size_type(hash & m_mask); }
+
+ private:
+ size_type m_mask;
+ const static size_type s_num_bits_in_size_type;
+ const static size_type s_highest_bit_1;
+ };
+
+ PB_DS_CLASS_T_DEC
+ const typename PB_DS_CLASS_C_DEC::size_type
+ PB_DS_CLASS_C_DEC::s_num_bits_in_size_type =
+ sizeof(typename PB_DS_CLASS_C_DEC::size_type) << 3;
+
+ PB_DS_CLASS_T_DEC
+ const typename PB_DS_CLASS_C_DEC::size_type PB_DS_CLASS_C_DEC::s_highest_bit_1 = static_cast<typename PB_DS_CLASS_C_DEC::size_type>(1) << (s_num_bits_in_size_type - 1);
+
+
+ PB_DS_CLASS_T_DEC
+ void
+ PB_DS_CLASS_C_DEC::
+ notify_resized(size_type size)
+ {
+ size_type i = 0;
+ while (size ^ s_highest_bit_1)
+ {
+ size <<= 1;
+ ++i;
+ }
+
+ m_mask = 1;
+ i += 2;
+ while (i++ < s_num_bits_in_size_type)
+ m_mask = (m_mask << 1) ^ 1;
+ }
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+ } // namespace detail
+} // namespace __gnu_pbds
+
+#endif