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Diffstat (limited to 'gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/hash_policy.hpp')
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diff --git a/gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/hash_policy.hpp b/gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/hash_policy.hpp new file mode 100644 index 000000000..24c0c4562 --- /dev/null +++ b/gcc-4.4.3/libstdc++-v3/include/ext/pb_ds/hash_policy.hpp @@ -0,0 +1,604 @@ +// -*- 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 hash_policy.hpp + * Contains hash-related policies. + */ + +#ifndef PB_DS_HASH_POLICY_HPP +#define PB_DS_HASH_POLICY_HPP + +#include <algorithm> +#include <vector> +#include <cmath> +#include <ext/pb_ds/exception.hpp> +#include <ext/pb_ds/detail/type_utils.hpp> +#include <ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp> +#include <ext/pb_ds/detail/hash_fn/mod_based_range_hashing.hpp> +#include <ext/pb_ds/detail/resize_policy/hash_load_check_resize_trigger_size_base.hpp> + +namespace __gnu_pbds +{ + // A null hash function, indicating that the combining hash function + // is actually a ranged hash function. + struct null_hash_fn + { }; + + // A null probe function, indicating that the combining probe + // function is actually a ranged probe function. + struct null_probe_fn + { }; + +#define PB_DS_CLASS_T_DEC template<typename Size_Type> +#define PB_DS_CLASS_C_DEC linear_probe_fn<Size_Type> + + // A probe sequence policy using fixed increments. + template<typename Size_Type = size_t> + class linear_probe_fn + { + public: + typedef Size_Type size_type; + + void + swap(PB_DS_CLASS_C_DEC& other); + + protected: + // Returns the i-th offset from the hash value. + inline size_type + operator()(size_type i) const; + }; + +#include <ext/pb_ds/detail/hash_fn/linear_probe_fn_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC + +#define PB_DS_CLASS_T_DEC template<typename Size_Type> +#define PB_DS_CLASS_C_DEC quadratic_probe_fn<Size_Type> + + // A probe sequence policy using square increments. + template<typename Size_Type = size_t> + class quadratic_probe_fn + { + public: + typedef Size_Type size_type; + + void + swap(PB_DS_CLASS_C_DEC& other); + + protected: + // Returns the i-th offset from the hash value. + inline size_type + operator()(size_type i) const; + }; + +#include <ext/pb_ds/detail/hash_fn/quadratic_probe_fn_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC + +#define PB_DS_CLASS_T_DEC template<typename Size_Type> +#define PB_DS_CLASS_C_DEC direct_mask_range_hashing<Size_Type> + + // A mask range-hashing class (uses a bit-mask). + template<typename Size_Type = size_t> + class direct_mask_range_hashing + : public detail::mask_based_range_hashing<Size_Type> + { + private: + typedef detail::mask_based_range_hashing<Size_Type> mask_based_base; + + public: + typedef Size_Type size_type; + + void + swap(PB_DS_CLASS_C_DEC& other); + + protected: + void + notify_resized(size_type size); + + // Transforms the __hash value hash into a ranged-hash value + // (using a bit-mask). + inline size_type + operator()(size_type hash) const; + }; + +#include <ext/pb_ds/detail/hash_fn/direct_mask_range_hashing_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC + +#define PB_DS_CLASS_T_DEC template<typename Size_Type> +#define PB_DS_CLASS_C_DEC direct_mod_range_hashing<Size_Type> + + // A mod range-hashing class (uses the modulo function). + template<typename Size_Type = size_t> + class direct_mod_range_hashing + : public detail::mod_based_range_hashing<Size_Type> + { + public: + typedef Size_Type size_type; + + void + swap(PB_DS_CLASS_C_DEC& other); + + protected: + void + notify_resized(size_type size); + + // Transforms the __hash value hash into a ranged-hash value + // (using a modulo operation). + inline size_type + operator()(size_type hash) const; + + private: + typedef detail::mod_based_range_hashing<size_type> mod_based_base; + }; + +#include <ext/pb_ds/detail/hash_fn/direct_mod_range_hashing_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC + +#define PB_DS_CLASS_T_DEC template<bool External_Load_Access, typename Size_Type> +#define PB_DS_CLASS_C_DEC hash_load_check_resize_trigger<External_Load_Access, Size_Type> +#define PB_DS_SIZE_BASE_C_DEC detail::hash_load_check_resize_trigger_size_base<Size_Type, External_Load_Access> + + // A resize trigger policy based on a load check. It keeps the + // load factor between some load factors load_min and load_max. + template<bool External_Load_Access = false, typename Size_Type = size_t> + class hash_load_check_resize_trigger : private PB_DS_SIZE_BASE_C_DEC + { + public: + typedef Size_Type size_type; + + enum + { + external_load_access = External_Load_Access + }; + + // Default constructor, or constructor taking load_min and + // load_max load factors between which this policy will keep the + // actual load. + hash_load_check_resize_trigger(float load_min = 0.125, + float load_max = 0.5); + + void + swap(hash_load_check_resize_trigger& other); + + virtual + ~hash_load_check_resize_trigger(); + + // Returns a pair of the minimal and maximal loads, respectively. + inline std::pair<float, float> + get_loads() const; + + // Sets the loads through a pair of the minimal and maximal + // loads, respectively. + void + set_loads(std::pair<float, float> load_pair); + + protected: + inline void + notify_insert_search_start(); + + inline void + notify_insert_search_collision(); + + inline void + notify_insert_search_end(); + + inline void + notify_find_search_start(); + + inline void + notify_find_search_collision(); + + inline void + notify_find_search_end(); + + inline void + notify_erase_search_start(); + + inline void + notify_erase_search_collision(); + + inline void + notify_erase_search_end(); + + // Notifies an element was inserted. The total number of entries + // in the table is num_entries. + inline void + notify_inserted(size_type num_entries); + + inline void + notify_erased(size_type num_entries); + + // Notifies the table was cleared. + void + notify_cleared(); + + // Notifies the table was resized as a result of this object's + // signifying that a resize is needed. + void + notify_resized(size_type new_size); + + void + notify_externally_resized(size_type new_size); + + inline bool + is_resize_needed() const; + + inline bool + is_grow_needed(size_type size, size_type num_entries) const; + + private: + virtual void + do_resize(size_type new_size); + + typedef PB_DS_SIZE_BASE_C_DEC size_base; + +#ifdef _GLIBCXX_DEBUG + void + assert_valid() const; +#endif + + float m_load_min; + float m_load_max; + size_type m_next_shrink_size; + size_type m_next_grow_size; + bool m_resize_needed; + }; + +#include <ext/pb_ds/detail/resize_policy/hash_load_check_resize_trigger_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC +#undef PB_DS_SIZE_BASE_C_DEC + +#define PB_DS_CLASS_T_DEC template<bool External_Load_Access, typename Size_Type> +#define PB_DS_CLASS_C_DEC cc_hash_max_collision_check_resize_trigger<External_Load_Access, Size_Type> + + // A resize trigger policy based on collision checks. It keeps the + // simulated load factor lower than some given load factor. + template<bool External_Load_Access = false, typename Size_Type = size_t> + class cc_hash_max_collision_check_resize_trigger + { + public: + typedef Size_Type size_type; + + enum + { + external_load_access = External_Load_Access + }; + + // Default constructor, or constructor taking load, a __load + // factor which it will attempt to maintain. + cc_hash_max_collision_check_resize_trigger(float load = 0.5); + + void + swap(PB_DS_CLASS_C_DEC& other); + + // Returns the current load. + inline float + get_load() const; + + // Sets the load; does not resize the container. + void + set_load(float load); + + protected: + inline void + notify_insert_search_start(); + + inline void + notify_insert_search_collision(); + + inline void + notify_insert_search_end(); + + inline void + notify_find_search_start(); + + inline void + notify_find_search_collision(); + + inline void + notify_find_search_end(); + + inline void + notify_erase_search_start(); + + inline void + notify_erase_search_collision(); + + inline void + notify_erase_search_end(); + + inline void + notify_inserted(size_type num_entries); + + inline void + notify_erased(size_type num_entries); + + void + notify_cleared(); + + // Notifies the table was resized as a result of this object's + // signifying that a resize is needed. + void + notify_resized(size_type new_size); + + void + notify_externally_resized(size_type new_size); + + inline bool + is_resize_needed() const; + + inline bool + is_grow_needed(size_type size, size_type num_entries) const; + + private: + void + calc_max_num_coll(); + + inline void + calc_resize_needed(); + + float m_load; + size_type m_size; + size_type m_num_col; + size_type m_max_col; + bool m_resize_needed; + }; + +#include <ext/pb_ds/detail/resize_policy/cc_hash_max_collision_check_resize_trigger_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC + +#define PB_DS_CLASS_T_DEC template<typename Size_Type> +#define PB_DS_CLASS_C_DEC hash_exponential_size_policy<Size_Type> + + // A size policy whose sequence of sizes form an exponential + // sequence (typically powers of 2. + template<typename Size_Type = size_t> + class hash_exponential_size_policy + { + public: + typedef Size_Type size_type; + + // Default constructor, or onstructor taking a start_size, or + // constructor taking a start size and grow_factor. The policy + // will use the sequence of sizes start_size, start_size* + // grow_factor, start_size* grow_factor^2, ... + hash_exponential_size_policy(size_type start_size = 8, + size_type grow_factor = 2); + + void + swap(PB_DS_CLASS_C_DEC& other); + + protected: + size_type + get_nearest_larger_size(size_type size) const; + + size_type + get_nearest_smaller_size(size_type size) const; + + private: + size_type m_start_size; + size_type m_grow_factor; + }; + +#include <ext/pb_ds/detail/resize_policy/hash_exponential_size_policy_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC + +#define PB_DS_CLASS_T_DEC +#define PB_DS_CLASS_C_DEC hash_prime_size_policy + + // A size policy whose sequence of sizes form a nearly-exponential + // sequence of primes. + class hash_prime_size_policy + { + public: + // Size type. + typedef size_t size_type; + + // Default constructor, or onstructor taking a start_size The + // policy will use the sequence of sizes approximately + // start_size, start_size* 2, start_size* 2^2, ... + hash_prime_size_policy(size_type start_size = 8); + + inline void + swap(PB_DS_CLASS_C_DEC& other); + + protected: + size_type + get_nearest_larger_size(size_type size) const; + + size_type + get_nearest_smaller_size(size_type size) const; + + private: + size_type m_start_size; + }; + +#include <ext/pb_ds/detail/resize_policy/hash_prime_size_policy_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC + +#define PB_DS_CLASS_T_DEC template<typename Size_Policy, typename Trigger_Policy, bool External_Size_Access, typename Size_Type> + +#define PB_DS_CLASS_C_DEC hash_standard_resize_policy<Size_Policy, Trigger_Policy, External_Size_Access, Size_Type> + + // A resize policy which delegates operations to size and trigger policies. + template<typename Size_Policy = hash_exponential_size_policy<>, + typename Trigger_Policy = hash_load_check_resize_trigger<>, + bool External_Size_Access = false, + typename Size_Type = size_t> + class hash_standard_resize_policy + : public Size_Policy, public Trigger_Policy + { + public: + typedef Size_Type size_type; + typedef Trigger_Policy trigger_policy; + typedef Size_Policy size_policy; + + enum + { + external_size_access = External_Size_Access + }; + + // Default constructor. + hash_standard_resize_policy(); + + // constructor taking some policies r_size_policy will be copied + // by the Size_Policy object of this object. + hash_standard_resize_policy(const Size_Policy& r_size_policy); + + // constructor taking some policies. r_size_policy will be + // copied by the Size_Policy object of this + // object. r_trigger_policy will be copied by the Trigger_Policy + // object of this object. + hash_standard_resize_policy(const Size_Policy& r_size_policy, + const Trigger_Policy& r_trigger_policy); + + virtual + ~hash_standard_resize_policy(); + + inline void + swap(PB_DS_CLASS_C_DEC& other); + + // Access to the Size_Policy object used. + Size_Policy& + get_size_policy(); + + // Const access to the Size_Policy object used. + const Size_Policy& + get_size_policy() const; + + // Access to the Trigger_Policy object used. + Trigger_Policy& + get_trigger_policy(); + + // Access to the Trigger_Policy object used. + const Trigger_Policy& + get_trigger_policy() const; + + // Returns the actual size of the container. + inline size_type + get_actual_size() const; + + // Resizes the container to suggested_new_size, a suggested size + // (the actual size will be determined by the Size_Policy + // object). + void + resize(size_type suggested_new_size); + + protected: + inline void + notify_insert_search_start(); + + inline void + notify_insert_search_collision(); + + inline void + notify_insert_search_end(); + + inline void + notify_find_search_start(); + + inline void + notify_find_search_collision(); + + inline void + notify_find_search_end(); + + inline void + notify_erase_search_start(); + + inline void + notify_erase_search_collision(); + + inline void + notify_erase_search_end(); + + inline void + notify_inserted(size_type num_e); + + inline void + notify_erased(size_type num_e); + + void + notify_cleared(); + + void + notify_resized(size_type new_size); + + inline bool + is_resize_needed() const; + + // Queries what the new size should be, when the container is + // resized naturally. The current __size of the container is + // size, and the number of used entries within the container is + // num_used_e. + size_type + get_new_size(size_type size, size_type num_used_e) const; + + private: + // Resizes to new_size. + virtual void + do_resize(size_type new_size); + + typedef Trigger_Policy trigger_policy_base; + + typedef Size_Policy size_policy_base; + + size_type m_size; + }; + +#include <ext/pb_ds/detail/resize_policy/hash_standard_resize_policy_imp.hpp> + +#undef PB_DS_CLASS_T_DEC +#undef PB_DS_CLASS_C_DEC + +} // namespace __gnu_pbds + +#endif |