3 // Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
5 // This file is part of the GNU ISO C++ Library. This library is free
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14 // General Public License for more details.
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19 // MA 02111-1307, USA.
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31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
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43 * @file cc_hash_max_collision_check_resize_trigger_imp.hpp
44 * Contains a resize trigger implementation.
49 cc_hash_max_collision_check_resize_trigger(float load) :
54 m_resize_needed(false)
60 notify_find_search_start()
66 notify_find_search_collision()
72 notify_find_search_end()
78 notify_insert_search_start()
84 notify_insert_search_collision()
90 notify_insert_search_end()
91 { calc_resize_needed(); }
96 notify_erase_search_start()
102 notify_erase_search_collision()
108 notify_erase_search_end()
114 notify_inserted(size_type)
120 notify_erased(size_type)
121 { m_resize_needed = true; }
127 { m_resize_needed = false; }
132 is_resize_needed() const
133 { return m_resize_needed; }
138 is_grow_needed(size_type /*size*/, size_type /*num_used_e*/) const
139 { return m_num_col >= m_max_col; }
144 notify_resized(size_type new_size)
148 #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
149 std::cerr << "chmccrt::notify_resized "
150 << static_cast<unsigned long>(new_size) << std::endl;
154 calc_resize_needed();
163 // max_col <-- \sqrt{2 load \ln( 2 m \ln( m ) ) }
164 const double ln_arg = 2 * m_size * std::log(double(m_size));
165 m_max_col = size_type(std::ceil(std::sqrt(2 * m_load * std::log(ln_arg))));
167 #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
168 std::cerr << "chmccrt::calc_max_num_coll "
169 << static_cast<unsigned long>(m_size) << " "
170 << static_cast<unsigned long>(m_max_col) << std::endl;
177 notify_externally_resized(size_type new_size)
178 { notify_resized(new_size); }
183 swap(PB_DS_CLASS_C_DEC& other)
185 std::swap(m_load, other.m_load);
186 std::swap(m_size, other.m_size);
187 std::swap(m_num_col, other.m_num_col);
188 std::swap(m_max_col, other.m_max_col);
189 std::swap(m_resize_needed, other.m_resize_needed);
197 PB_DS_STATIC_ASSERT(access, external_load_access);
205 { m_resize_needed = m_resize_needed || m_num_col >= m_max_col; }
212 PB_DS_STATIC_ASSERT(access, external_load_access);
215 calc_resize_needed();