X-Git-Url: http://wagnertech.de/git?a=blobdiff_plain;f=i686-linux-gnu-4.7%2Fusr%2Finclude%2Fc%2B%2B%2F4.7%2Fext%2Fpb_ds%2Fdetail%2Fhash_fn%2Fmask_based_range_hashing.hpp;fp=i686-linux-gnu-4.7%2Fusr%2Finclude%2Fc%2B%2B%2F4.7%2Fext%2Fpb_ds%2Fdetail%2Fhash_fn%2Fmask_based_range_hashing.hpp;h=6fe8465c64518547b260638666229fef7a08b392;hb=94df942c2c7bd3457276fe5b7367623cbb8c1302;hp=0000000000000000000000000000000000000000;hpb=4dd7d9155a920895ff7b1cb6b9c9c676aa62000a;p=cross.git diff --git a/i686-linux-gnu-4.7/usr/include/c++/4.7/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp b/i686-linux-gnu-4.7/usr/include/c++/4.7/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp new file mode 100644 index 0000000..6fe8465 --- /dev/null +++ b/i686-linux-gnu-4.7/usr/include/c++/4.7/ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp @@ -0,0 +1,101 @@ +// -*- 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 +// . + +// 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 + { + /// Range hashing policy. + template + 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; + }; + + template + const typename mask_based_range_hashing::size_type + mask_based_range_hashing::s_num_bits_in_size_type = + sizeof(typename mask_based_range_hashing::size_type) << 3; + + template + const typename mask_based_range_hashing::size_type mask_based_range_hashing::s_highest_bit_1 = static_cast::size_type>(1) << (s_num_bits_in_size_type - 1); + + + template + void + mask_based_range_hashing:: + 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; + } + } // namespace detail +} // namespace __gnu_pbds + +#endif