summaryrefslogtreecommitdiffstats
blob: 3428ed7ae262f1098ca39ec368550a47346beb16 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266

// Copyright (C) 2003-2004 Jeremy B. Maitin-Shepard.
// Copyright (C) 2005-2011 Daniel James
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#ifndef BOOST_UNORDERED_DETAIL_UTIL_HPP_INCLUDED
#define BOOST_UNORDERED_DETAIL_UTIL_HPP_INCLUDED

#include <boost/config.hpp>
#if defined(BOOST_HAS_PRAGMA_ONCE)
#pragma once
#endif

#include <boost/type_traits/is_convertible.hpp>
#include <boost/type_traits/is_empty.hpp>
#include <boost/iterator/iterator_categories.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/detail/select_type.hpp>
#include <boost/move/move.hpp>
#include <boost/preprocessor/seq/size.hpp>
#include <boost/preprocessor/seq/enum.hpp>
#include <boost/swap.hpp>

namespace boost { namespace unordered { namespace detail {

    static const float minimum_max_load_factor = 1e-3f;
    static const std::size_t default_bucket_count = 11;
    struct move_tag {};
    struct empty_emplace {};

    namespace func {
        template <class T>
        inline void ignore_unused_variable_warning(T const&) {}
    }

    ////////////////////////////////////////////////////////////////////////////
    // iterator SFINAE

    template <typename I>
    struct is_forward :
        boost::is_convertible<
            typename boost::iterator_traversal<I>::type,
            boost::forward_traversal_tag>
    {};

    template <typename I, typename ReturnType>
    struct enable_if_forward :
        boost::enable_if_c<
            boost::unordered::detail::is_forward<I>::value,
            ReturnType>
    {};

    template <typename I, typename ReturnType>
    struct disable_if_forward :
        boost::disable_if_c<
            boost::unordered::detail::is_forward<I>::value,
            ReturnType>
    {};

    ////////////////////////////////////////////////////////////////////////////
    // primes

#define BOOST_UNORDERED_PRIMES \
    (17ul)(29ul)(37ul)(53ul)(67ul)(79ul) \
    (97ul)(131ul)(193ul)(257ul)(389ul)(521ul)(769ul) \
    (1031ul)(1543ul)(2053ul)(3079ul)(6151ul)(12289ul)(24593ul) \
    (49157ul)(98317ul)(196613ul)(393241ul)(786433ul) \
    (1572869ul)(3145739ul)(6291469ul)(12582917ul)(25165843ul) \
    (50331653ul)(100663319ul)(201326611ul)(402653189ul)(805306457ul) \
    (1610612741ul)(3221225473ul)(4294967291ul)

    template<class T> struct prime_list_template
    {
        static std::size_t const value[];

#if !defined(SUNPRO_CC)
        static std::ptrdiff_t const length;
#else
        static std::ptrdiff_t const length
            = BOOST_PP_SEQ_SIZE(BOOST_UNORDERED_PRIMES);
#endif
    };

    template<class T>
    std::size_t const prime_list_template<T>::value[] = {
        BOOST_PP_SEQ_ENUM(BOOST_UNORDERED_PRIMES)
    };

#if !defined(SUNPRO_CC)
    template<class T>
    std::ptrdiff_t const prime_list_template<T>::length
        = BOOST_PP_SEQ_SIZE(BOOST_UNORDERED_PRIMES);
#endif

#undef BOOST_UNORDERED_PRIMES

    typedef prime_list_template<std::size_t> prime_list;

    // no throw
    inline std::size_t next_prime(std::size_t num) {
        std::size_t const* const prime_list_begin = prime_list::value;
        std::size_t const* const prime_list_end = prime_list_begin +
            prime_list::length;
        std::size_t const* bound =
            std::lower_bound(prime_list_begin, prime_list_end, num);
        if(bound == prime_list_end)
            bound--;
        return *bound;
    }

    // no throw
    inline std::size_t prev_prime(std::size_t num) {
        std::size_t const* const prime_list_begin = prime_list::value;
        std::size_t const* const prime_list_end = prime_list_begin +
            prime_list::length;
        std::size_t const* bound =
            std::upper_bound(prime_list_begin,prime_list_end, num);
        if(bound != prime_list_begin)
            bound--;
        return *bound;
    }

    ////////////////////////////////////////////////////////////////////////////
    // insert_size/initial_size

#if !defined(BOOST_NO_STD_DISTANCE)

    using ::std::distance;

#else

    template <class ForwardIterator>
    inline std::size_t distance(ForwardIterator i, ForwardIterator j) {
        std::size_t x;
        std::distance(i, j, x);
        return x;
    }

#endif

    template <class I>
    inline typename
        boost::unordered::detail::enable_if_forward<I, std::size_t>::type
        insert_size(I i, I j)
    {
        return std::distance(i, j);
    }

    template <class I>
    inline typename
        boost::unordered::detail::disable_if_forward<I, std::size_t>::type
        insert_size(I, I)
    {
        return 1;
    }

    template <class I>
    inline std::size_t initial_size(I i, I j,
        std::size_t num_buckets =
            boost::unordered::detail::default_bucket_count)
    {
        // TODO: Why +1?
        return (std::max)(
            boost::unordered::detail::insert_size(i, j) + 1,
            num_buckets);
    }

    ////////////////////////////////////////////////////////////////////////////
    // compressed

    template <typename T, int Index>
    struct compressed_base : private T
    {
        compressed_base(T const& x) : T(x) {}
        compressed_base(T& x, move_tag) : T(boost::move(x)) {}

        T& get() { return *this; }
        T const& get() const { return *this; }
    };
    
    template <typename T, int Index>
    struct uncompressed_base
    {
        uncompressed_base(T const& x) : value_(x) {}
        uncompressed_base(T& x, move_tag) : value_(boost::move(x)) {}

        T& get() { return value_; }
        T const& get() const { return value_; }
    private:
        T value_;
    };
    
    template <typename T, int Index>
    struct generate_base
      : boost::detail::if_true<
            boost::is_empty<T>::value
        >:: BOOST_NESTED_TEMPLATE then<
            boost::unordered::detail::compressed_base<T, Index>,
            boost::unordered::detail::uncompressed_base<T, Index>
        >
    {};
    
    template <typename T1, typename T2>
    struct compressed
      : private boost::unordered::detail::generate_base<T1, 1>::type,
        private boost::unordered::detail::generate_base<T2, 2>::type
    {
        typedef typename generate_base<T1, 1>::type base1;
        typedef typename generate_base<T2, 2>::type base2;

        typedef T1 first_type;
        typedef T2 second_type;
        
        first_type& first() {
            return static_cast<base1*>(this)->get();
        }

        first_type const& first() const {
            return static_cast<base1 const*>(this)->get();
        }

        second_type& second() {
            return static_cast<base2*>(this)->get();
        }

        second_type const& second() const {
            return static_cast<base2 const*>(this)->get();
        }

        template <typename First, typename Second>
        compressed(First const& x1, Second const& x2)
            : base1(x1), base2(x2) {}

        compressed(compressed const& x)
            : base1(x.first()), base2(x.second()) {}

        compressed(compressed& x, move_tag m)
            : base1(x.first(), m), base2(x.second(), m) {}

        void assign(compressed const& x)
        {
            first() = x.first();
            second() = x.second();
        }

        void move_assign(compressed& x)
        {
            first() = boost::move(x.first());
            second() = boost::move(x.second());
        }
        
        void swap(compressed& x)
        {
            boost::swap(first(), x.first());
            boost::swap(second(), x.second());
        }

    private:
        // Prevent assignment just to make use of assign or
        // move_assign explicit.
        compressed& operator=(compressed const&);
    };
}}}

#endif