/root/bitcoin/src/util/bitdeque.h

Source
// Copyright (c) 2022-present The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#ifndef BITCOIN_UTIL_BITDEQUE_H
#define BITCOIN_UTIL_BITDEQUE_H

#include <bitset>
#include <cstddef>
#include <deque>
#include <limits>
#include <stdexcept>
#include <tuple>
#include <util/overflow.h>

/** Class that mimics std::deque<bool>, but with std::vector<bool>'s bit packing.
 *
 * BITS_PER_WORD selects the (minimum) number of bits that are allocated at once.
 * Larger values reduce the asymptotic memory usage overhead, at the cost of
 * needing larger up-front allocations. The default is 4096 bytes.
 */
template<int BITS_PER_WORD = 4096 * 8>
class bitdeque
{
    // Internal definitions
    using word_type = std::bitset<BITS_PER_WORD>;
    using deque_type = std::deque<word_type>;
    static_assert(BITS_PER_WORD > 0);

    // Forward and friend declarations of iterator types.
    template<bool Const> class Iterator;
    template<bool Const> friend class Iterator;

    /** Iterator to a bitdeque element, const or not. */
    template<bool Const>
    class Iterator
    {
        using deque_iterator = std::conditional_t<Const, typename deque_type::const_iterator, typename deque_type::iterator>;

        deque_iterator m_it;
        int m_bitpos{0};
        Iterator(const deque_iterator& it, int bitpos) : m_it(it), m_bitpos(bitpos) {}
        friend class bitdeque;

    public:
        using iterator_category = std::random_access_iterator_tag;
        using value_type = bool;
        using pointer = void;
        using const_pointer = void;
        using reference = std::conditional_t<Const, bool, typename word_type::reference>;
        using const_reference = bool;
        using difference_type = std::ptrdiff_t;

        /** Default constructor. */
        Iterator() = default;

        /** Default copy constructor. */
        Iterator(const Iterator&) = default;

        /** Conversion from non-const to const iterator. */
        template<bool ConstArg = Const, typename = std::enable_if_t<Const && ConstArg>>
        Iterator(const Iterator<false>& x) : m_it(x.m_it), m_bitpos(x.m_bitpos) {}

        Iterator& operator+=(difference_type dist)
        {
            if (dist > 0) {
                if (dist + m_bitpos >= BITS_PER_WORD) {
                    ++m_it;
                    dist -= BITS_PER_WORD - m_bitpos;
                    m_bitpos = 0;
                }
                auto jump = dist / BITS_PER_WORD;
                m_it += jump;
                m_bitpos += dist - jump * BITS_PER_WORD;
            } else if (dist < 0) {
                dist = -dist;
                if (dist > m_bitpos) {
                    --m_it;
                    dist -= m_bitpos + 1;
                    m_bitpos = BITS_PER_WORD - 1;
                }
                auto jump = dist / BITS_PER_WORD;
                m_it -= jump;
                m_bitpos -= dist - jump * BITS_PER_WORD;
            }
            return *this;
        }

        friend difference_type operator-(const Iterator& x, const Iterator& y)
        {
            return BITS_PER_WORD * (x.m_it - y.m_it) + x.m_bitpos - y.m_bitpos;
        }

        Iterator& operator=(const Iterator&) = default;
        Iterator& operator-=(difference_type dist) { return operator+=(-dist); }
        Iterator& operator++() { ++m_bitpos; if (m_bitpos == BITS_PER_WORD) { m_bitpos = 0; ++m_it; }; return *this; }
        Iterator operator++(int) { auto ret{*this}; operator++(); return ret; }
        Iterator& operator--() { if (m_bitpos == 0) { m_bitpos = BITS_PER_WORD; --m_it; }; --m_bitpos; return *this; }
        Iterator operator--(int) { auto ret{*this}; operator--(); return ret; }
        friend Iterator operator+(Iterator x, difference_type dist) { x += dist; return x; }
        friend Iterator operator+(difference_type dist, Iterator x) { x += dist; return x; }
        friend Iterator operator-(Iterator x, difference_type dist) { x -= dist; return x; }
        friend auto operator<=>(const Iterator& x, const Iterator& y) { return std::tie(x.m_it, x.m_bitpos) <=> std::tie(y.m_it, y.m_bitpos); }
        friend bool operator==(const Iterator& x, const Iterator& y) { return x.m_it == y.m_it && x.m_bitpos == y.m_bitpos; }
        reference operator*() const { return (*m_it)[m_bitpos]; }
        reference operator[](difference_type pos) const { return *(*this + pos); }
    };

public:
    using value_type = bool;
    using size_type = std::size_t;
    using difference_type = typename deque_type::difference_type;
    using reference = typename word_type::reference;
    using const_reference = bool;
    using iterator = Iterator<false>;
    using const_iterator = Iterator<true>;
    using pointer = void;
    using const_pointer = void;
    using reverse_iterator = std::reverse_iterator<iterator>;
    using const_reverse_iterator = std::reverse_iterator<const_iterator>;

private:
    /** Deque of bitsets storing the actual bit data. */
    deque_type m_deque;

    /** Number of unused bits at the front of m_deque.front(). */
    int m_pad_begin;

    /** Number of unused bits at the back of m_deque.back(). */
    int m_pad_end;

    /** Shrink the container by n bits, removing from the end. */
    void erase_back(size_type n)
    {
        if (n >= static_cast<size_type>(BITS_PER_WORD - m_pad_end)) {
            n -= BITS_PER_WORD - m_pad_end;
            m_pad_end = 0;
            m_deque.erase(m_deque.end() - 1 - (n / BITS_PER_WORD), m_deque.end());
            n %= BITS_PER_WORD;
        }
        if (n) {
            auto& last = m_deque.back();
            while (n) {
                last.reset(BITS_PER_WORD - 1 - m_pad_end);
                ++m_pad_end;
                --n;
            }
        }
    }

    /** Extend the container by n bits, adding at the end. */
    void extend_back(size_type n)
    {
        if (n > static_cast<size_type>(m_pad_end)) {
            n -= m_pad_end + 1;
            m_pad_end = BITS_PER_WORD - 1;
            m_deque.insert(m_deque.end(), 1 + (n / BITS_PER_WORD), {});
            n %= BITS_PER_WORD;
        }
        m_pad_end -= n;
    }

    /** Shrink the container by n bits, removing from the beginning. */
    void erase_front(size_type n)
    {
        if (n >= static_cast<size_type>(BITS_PER_WORD - m_pad_begin)) {
            n -= BITS_PER_WORD - m_pad_begin;
            m_pad_begin = 0;
            m_deque.erase(m_deque.begin(), m_deque.begin() + 1 + (n / BITS_PER_WORD));
            n %= BITS_PER_WORD;
        }
        if (n) {
            auto& first = m_deque.front();
            while (n) {
                first.reset(m_pad_begin);
                ++m_pad_begin;
                --n;
            }
        }
    }

    /** Extend the container by n bits, adding at the beginning. */
    void extend_front(size_type n)
    {
        if (n > static_cast<size_type>(m_pad_begin)) {
            n -= m_pad_begin + 1;
            m_pad_begin = BITS_PER_WORD - 1;
            m_deque.insert(m_deque.begin(), 1 + (n / BITS_PER_WORD), {});
            n %= BITS_PER_WORD;
        }
        m_pad_begin -= n;
    }

    /** Insert a sequence of falses anywhere in the container. */
    void insert_zeroes(size_type before, size_type count)
    {
        size_type after = size() - before;
        if (before < after) {
            extend_front(count);
            std::move(begin() + count, begin() + count + before, begin());
        } else {
            extend_back(count);
            std::move_backward(begin() + before, begin() + before + after, end());
        }
    }

public:
    /** Construct an empty container. */
    explicit bitdeque() : m_pad_begin{0}, m_pad_end{0} {}

    /** Set the container equal to count times the value of val. */
    void assign(size_type count, bool val)
    {
        m_deque.clear();
        m_deque.resize(CeilDiv(count, size_type{BITS_PER_WORD}));
        m_pad_begin = 0;
        m_pad_end = 0;
        if (val) {
            for (auto& elem : m_deque) elem.flip();
        }
        if (count % BITS_PER_WORD) {
            erase_back(BITS_PER_WORD - (count % BITS_PER_WORD));
        }
    }

    /** Construct a container containing count times the value of val. */
    bitdeque(size_type count, bool val) { assign(count, val); }

    /** Construct a container containing count false values. */
    explicit bitdeque(size_t count) { assign(count, false); }

    /** Copy constructor. */
    bitdeque(const bitdeque&) = default;

    /** Move constructor. */
    bitdeque(bitdeque&&) noexcept = default;

    /** Copy assignment operator. */
    bitdeque& operator=(const bitdeque& other) = default;

    /** Move assignment operator. */
    bitdeque& operator=(bitdeque&& other) noexcept = default;

    // Iterator functions.
    iterator begin() noexcept { return {m_deque.begin(), m_pad_begin}; }
    iterator end() noexcept { return iterator{m_deque.end(), 0} - m_pad_end; }
    const_iterator begin() const noexcept { return const_iterator{m_deque.cbegin(), m_pad_begin}; }
    const_iterator cbegin() const noexcept { return const_iterator{m_deque.cbegin(), m_pad_begin}; }
    const_iterator end() const noexcept { return const_iterator{m_deque.cend(), 0} - m_pad_end; }
    const_iterator cend() const noexcept { return const_iterator{m_deque.cend(), 0} - m_pad_end; }
    reverse_iterator rbegin() noexcept { return reverse_iterator{end()}; }
    reverse_iterator rend() noexcept { return reverse_iterator{begin()}; }
    const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator{cend()}; }
    const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator{cend()}; }
    const_reverse_iterator rend() const noexcept { return const_reverse_iterator{cbegin()}; }
    const_reverse_iterator crend() const noexcept { return const_reverse_iterator{cbegin()}; }

    /** Count the number of bits in the container. */
    size_type size() const noexcept { return m_deque.size() * BITS_PER_WORD - m_pad_begin - m_pad_end; }

    /** Determine whether the container is empty. */
    bool empty() const noexcept
    {
        return m_deque.size() == 0 || (m_deque.size() == 1 && (m_pad_begin + m_pad_end == BITS_PER_WORD));
    }

    /** Return the maximum size of the container. */
    size_type max_size() const noexcept
    {
        if (m_deque.max_size() < std::numeric_limits<difference_type>::max() / BITS_PER_WORD) {
            return m_deque.max_size() * BITS_PER_WORD;
        } else {
            return std::numeric_limits<difference_type>::max();
        }
    }

    /** Set the container equal to the bits in [first,last). */
    template<typename It>
    void assign(It first, It last)
    {
        size_type count = std::distance(first, last);
        assign(count, false);
        auto it = begin();
        while (first != last) {
            *(it++) = *(first++);
        }
    }

    /** Set the container equal to the bits in ilist. */
    void assign(std::initializer_list<bool> ilist)
    {
        assign(ilist.size(), false);
        auto it = begin();
        auto init = ilist.begin();
        while (init != ilist.end()) {
            *(it++) = *(init++);
        }
    }

    /** Set the container equal to the bits in ilist. */
    bitdeque& operator=(std::initializer_list<bool> ilist)
    {
        assign(ilist);
        return *this;
    }

    /** Construct a container containing the bits in [first,last). */
    template<typename It>
    bitdeque(It first, It last) { assign(first, last); }

    /** Construct a container containing the bits in ilist. */
    bitdeque(std::initializer_list<bool> ilist) { assign(ilist); }

    // Access an element of the container, with bounds checking.
    reference at(size_type position)
    {
        if (position >= size()) throw std::out_of_range("bitdeque::at() out of range");
        return begin()[position];
    }
    const_reference at(size_type position) const
    {
        if (position >= size()) throw std::out_of_range("bitdeque::at() out of range");
        return cbegin()[position];
    }

    // Access elements of the container without bounds checking.
    reference operator[](size_type position) { return begin()[position]; }
    const_reference operator[](size_type position) const { return cbegin()[position]; }
    reference front() { return *begin(); }
    const_reference front() const { return *cbegin(); }
    reference back() { return end()[-1]; }
    const_reference back() const { return cend()[-1]; }

    /** Release unused memory. */
    void shrink_to_fit()
    {
        m_deque.shrink_to_fit();
    }

    /** Empty the container. */
    void clear() noexcept
    {
        m_deque.clear();
        m_pad_begin = m_pad_end = 0;
    }

    // Append an element to the container.
    void push_back(bool val)
    {
        extend_back(1);
        back() = val;
    }
    reference emplace_back(bool val)
    {
        extend_back(1);
        auto ref = back();
        ref = val;
        return ref;
    }

    // Prepend an element to the container.
    void push_front(bool val)
    {
        extend_front(1);
        front() = val;
    }
    reference emplace_front(bool val)
    {
        extend_front(1);
        auto ref = front();
        ref = val;
        return ref;
    }

    // Remove the last element from the container.
    void pop_back()
    {
        erase_back(1);
    }

    // Remove the first element from the container.
    void pop_front()
    {
        erase_front(1);
    }

    /** Resize the container. */
    void resize(size_type n)
    {
        if (n < size()) {
            erase_back(size() - n);
        } else {
            extend_back(n - size());
        }
    }

    // Swap two containers.
    void swap(bitdeque& other) noexcept
    {
        std::swap(m_deque, other.m_deque);
        std::swap(m_pad_begin, other.m_pad_begin);
        std::swap(m_pad_end, other.m_pad_end);
    }
    friend void swap(bitdeque& b1, bitdeque& b2) noexcept { b1.swap(b2); }

    // Erase elements from the container.
    iterator erase(const_iterator first, const_iterator last)
    {
        size_type before = std::distance(cbegin(), first);
        size_type dist = std::distance(first, last);
        size_type after = std::distance(last, cend());
        if (before < after) {
            std::move_backward(begin(), begin() + before, end() - after);
            erase_front(dist);
            return begin() + before;
        } else {
            std::move(end() - after, end(), begin() + before);
            erase_back(dist);
            return end() - after;
        }
    }

    iterator erase(iterator first, iterator last) { return erase(const_iterator{first}, const_iterator{last}); }
    iterator erase(const_iterator pos) { return erase(pos, pos + 1); }
    iterator erase(iterator pos) { return erase(const_iterator{pos}, const_iterator{pos} + 1); }

    // Insert elements into the container.
    iterator insert(const_iterator pos, bool val)
    {
        size_type before = pos - cbegin();
        insert_zeroes(before, 1);
        auto it = begin() + before;
        *it = val;
        return it;
    }

    iterator emplace(const_iterator pos, bool val) { return insert(pos, val); }

    iterator insert(const_iterator pos, size_type count, bool val)
    {
        size_type before = pos - cbegin();
        insert_zeroes(before, count);
        auto it_begin = begin() + before;
        auto it = it_begin;
        auto it_end = it + count;
        while (it != it_end) *(it++) = val;
        return it_begin;
    }

    template<typename It>
    iterator insert(const_iterator pos, It first, It last)
    {
        size_type before = pos - cbegin();
        size_type count = std::distance(first, last);
        insert_zeroes(before, count);
        auto it_begin = begin() + before;
        auto it = it_begin;
        while (first != last) {
            *(it++) = *(first++);
        }
        return it_begin;
    }
};

#endif // BITCOIN_UTIL_BITDEQUE_H

Bitcoin Core Fuzz Coverage Report

Coverage Report

Created: 2026-03-24 13:57

Line	Count	Source
1		// Copyright (c) 2022-present The Bitcoin Core developers
2		// Distributed under the MIT software license, see the accompanying
3		// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5		#ifndef BITCOIN_UTIL_BITDEQUE_H
6		#define BITCOIN_UTIL_BITDEQUE_H
7
8		#include <bitset>
9		#include <cstddef>
10		#include <deque>
11		#include <limits>
12		#include <stdexcept>
13		#include <tuple>
14		#include <util/overflow.h>
15
16		/** Class that mimics std::deque<bool>, but with std::vector<bool>'s bit packing.
17		*
18		* BITS_PER_WORD selects the (minimum) number of bits that are allocated at once.
19		* Larger values reduce the asymptotic memory usage overhead, at the cost of
20		* needing larger up-front allocations. The default is 4096 bytes.
21		*/
22		template<int BITS_PER_WORD = 4096 * 8>
23		class bitdeque
24		{
25		// Internal definitions
26		using word_type = std::bitset<BITS_PER_WORD>;
27		using deque_type = std::deque<word_type>;
28		static_assert(BITS_PER_WORD > 0);
29
30		// Forward and friend declarations of iterator types.
31		template<bool Const> class Iterator;
32		template<bool Const> friend class Iterator;
33
34		/** Iterator to a bitdeque element, const or not. */
35		template<bool Const>
36		class Iterator
37		{
38		using deque_iterator = std::conditional_t<Const, typename deque_type::const_iterator, typename deque_type::iterator>;
39
40		deque_iterator m_it;
41		int m_bitpos{0};
42	0	Iterator(const deque_iterator& it, int bitpos) : m_it(it), m_bitpos(bitpos) {} Unexecuted instantiation: bitdeque<128>::Iterator<false>::Iterator(std::_Deque_iterator<std::bitset<128ul>, std::bitset<128ul>&, std::bitset<128ul>> const&, int) Unexecuted instantiation: bitdeque<128>::Iterator<true>::Iterator(std::_Deque_iterator<std::bitset<128ul>, std::bitset<128ul> const&, std::bitset<128ul> const> const&, int) Unexecuted instantiation: bitdeque<32768>::Iterator<false>::Iterator(std::_Deque_iterator<std::bitset<32768ul>, std::bitset<32768ul>&, std::bitset<32768ul>*> const&, int)
43		friend class bitdeque;
44
45		public:
46		using iterator_category = std::random_access_iterator_tag;
47		using value_type = bool;
48		using pointer = void;
49		using const_pointer = void;
50		using reference = std::conditional_t<Const, bool, typename word_type::reference>;
51		using const_reference = bool;
52		using difference_type = std::ptrdiff_t;
53
54		/** Default constructor. */
55		Iterator() = default;
56
57		/** Default copy constructor. */
58	0	Iterator(const Iterator&) = default; Unexecuted instantiation: bitdeque<128>::Iterator<false>::Iterator(bitdeque<128>::Iterator<false> const&) Unexecuted instantiation: bitdeque<128>::Iterator<true>::Iterator(bitdeque<128>::Iterator<true> const&) Unexecuted instantiation: bitdeque<32768>::Iterator<false>::Iterator(bitdeque<32768>::Iterator<false> const&)
59
60		/** Conversion from non-const to const iterator. */
61		template<bool ConstArg = Const, typename = std::enable_if_t<Const && ConstArg>>
62	0	Iterator(const Iterator<false>& x) : m_it(x.m_it), m_bitpos(x.m_bitpos) {}
63
64		Iterator& operator+=(difference_type dist)
65	0	{
66	0	if (dist > 0) {
67	0	if (dist + m_bitpos >= BITS_PER_WORD) {
68	0	++m_it;
69	0	dist -= BITS_PER_WORD - m_bitpos;
70	0	m_bitpos = 0;
71	0	}
72	0	auto jump = dist / BITS_PER_WORD;
73	0	m_it += jump;
74	0	m_bitpos += dist - jump * BITS_PER_WORD;
75	0	} else if (dist < 0) {
76	0	dist = -dist;
77	0	if (dist > m_bitpos) {
78	0	--m_it;
79	0	dist -= m_bitpos + 1;
80	0	m_bitpos = BITS_PER_WORD - 1;
81	0	}
82	0	auto jump = dist / BITS_PER_WORD;
83	0	m_it -= jump;
84	0	m_bitpos -= dist - jump * BITS_PER_WORD;
85	0	}
86	0	return *this;
87	0	} Unexecuted instantiation: bitdeque<128>::Iterator<false>::operator+=(long) Unexecuted instantiation: bitdeque<128>::Iterator<true>::operator+=(long) Unexecuted instantiation: bitdeque<32768>::Iterator<false>::operator+=(long)
88
89		friend difference_type operator-(const Iterator& x, const Iterator& y)
90	0	{
91	0	return BITS_PER_WORD * (x.m_it - y.m_it) + x.m_bitpos - y.m_bitpos;
92	0	} Unexecuted instantiation: operator-(bitdeque<128>::Iterator<false> const&, bitdeque<128>::Iterator<false> const&) Unexecuted instantiation: operator-(bitdeque<128>::Iterator<true> const&, bitdeque<128>::Iterator<true> const&)
93
94		Iterator& operator=(const Iterator&) = default;
95	0	Iterator& operator-=(difference_type dist) { return operator+=(-dist); } Unexecuted instantiation: bitdeque<128>::Iterator<false>::operator-=(long) Unexecuted instantiation: bitdeque<128>::Iterator<true>::operator-=(long) Unexecuted instantiation: bitdeque<32768>::Iterator<false>::operator-=(long)
96	0	Iterator& operator++() { ++m_bitpos; if (m_bitpos == BITS_PER_WORD) { m_bitpos = 0; ++m_it; }; return *this; }
97	0	Iterator operator++(int) { auto ret{*this}; operator++(); return ret; }
98	0	Iterator& operator--() { if (m_bitpos == 0) { m_bitpos = BITS_PER_WORD; --m_it; }; --m_bitpos; return *this; }
99		Iterator operator--(int) { auto ret{*this}; operator--(); return ret; }
100	0	friend Iterator operator+(Iterator x, difference_type dist) { x += dist; return x; } Unexecuted instantiation: operator+(bitdeque<128>::Iterator<false>, long) Unexecuted instantiation: operator+(bitdeque<128>::Iterator<true>, long) Unexecuted instantiation: operator+(bitdeque<32768>::Iterator<false>, long)
101		friend Iterator operator+(difference_type dist, Iterator x) { x += dist; return x; }
102	0	friend Iterator operator-(Iterator x, difference_type dist) { x -= dist; return x; } Unexecuted instantiation: operator-(bitdeque<128>::Iterator<false>, long) Unexecuted instantiation: operator-(bitdeque<128>::Iterator<true>, long) Unexecuted instantiation: operator-(bitdeque<32768>::Iterator<false>, long)
103	0	friend auto operator<=>(const Iterator& x, const Iterator& y) { return std::tie(x.m_it, x.m_bitpos) <=> std::tie(y.m_it, y.m_bitpos); } Unexecuted instantiation: operator<=>(bitdeque<128>::Iterator<false> const&, bitdeque<128>::Iterator<false> const&) Unexecuted instantiation: operator<=>(bitdeque<128>::Iterator<true> const&, bitdeque<128>::Iterator<true> const&)
104	0	friend bool operator==(const Iterator& x, const Iterator& y) { return x.m_it == y.m_it && x.m_bitpos == y.m_bitpos; } Unexecuted instantiation: operator==(bitdeque<128>::Iterator<true> const&, bitdeque<128>::Iterator<true> const&) Unexecuted instantiation: operator==(bitdeque<128>::Iterator<false> const&, bitdeque<128>::Iterator<false> const&)
105	0	reference operator() const { return (m_it)[m_bitpos]; } Unexecuted instantiation: bitdeque<128>::Iterator<false>::operator() const Unexecuted instantiation: bitdeque<128>::Iterator<true>::operator() const Unexecuted instantiation: bitdeque<32768>::Iterator<false>::operator*() const
106	0	reference operator[](difference_type pos) const { return (this + pos); } Unexecuted instantiation: bitdeque<128>::Iterator<false>::operator[](long) const Unexecuted instantiation: bitdeque<128>::Iterator<true>::operator[](long) const Unexecuted instantiation: bitdeque<32768>::Iterator<false>::operator[](long) const
107		};
108
109		public:
110		using value_type = bool;
111		using size_type = std::size_t;
112		using difference_type = typename deque_type::difference_type;
113		using reference = typename word_type::reference;
114		using const_reference = bool;
115		using iterator = Iterator<false>;
116		using const_iterator = Iterator<true>;
117		using pointer = void;
118		using const_pointer = void;
119		using reverse_iterator = std::reverse_iterator<iterator>;
120		using const_reverse_iterator = std::reverse_iterator<const_iterator>;
121
122		private:
123		/** Deque of bitsets storing the actual bit data. */
124		deque_type m_deque;
125
126		/** Number of unused bits at the front of m_deque.front(). */
127		int m_pad_begin;
128
129		/** Number of unused bits at the back of m_deque.back(). */
130		int m_pad_end;
131
132		/** Shrink the container by n bits, removing from the end. */
133		void erase_back(size_type n)
134	0	{
135	0	if (n >= static_cast<size_type>(BITS_PER_WORD - m_pad_end)) {
136	0	n -= BITS_PER_WORD - m_pad_end;
137	0	m_pad_end = 0;
138	0	m_deque.erase(m_deque.end() - 1 - (n / BITS_PER_WORD), m_deque.end());
139	0	n %= BITS_PER_WORD;
140	0	}
141	0	if (n) {
142	0	auto& last = m_deque.back();
143	0	while (n) {
144	0	last.reset(BITS_PER_WORD - 1 - m_pad_end);
145	0	++m_pad_end;
146	0	--n;
147	0	}
148	0	}
149	0	}
150
151		/** Extend the container by n bits, adding at the end. */
152		void extend_back(size_type n)
153	0	{
154	0	if (n > static_cast<size_type>(m_pad_end)) {
155	0	n -= m_pad_end + 1;
156	0	m_pad_end = BITS_PER_WORD - 1;
157	0	m_deque.insert(m_deque.end(), 1 + (n / BITS_PER_WORD), {});
158	0	n %= BITS_PER_WORD;
159	0	}
160	0	m_pad_end -= n;
161	0	} Unexecuted instantiation: bitdeque<128>::extend_back(unsigned long) Unexecuted instantiation: bitdeque<32768>::extend_back(unsigned long)
162
163		/** Shrink the container by n bits, removing from the beginning. */
164		void erase_front(size_type n)
165	0	{
166	0	if (n >= static_cast<size_type>(BITS_PER_WORD - m_pad_begin)) {
167	0	n -= BITS_PER_WORD - m_pad_begin;
168	0	m_pad_begin = 0;
169	0	m_deque.erase(m_deque.begin(), m_deque.begin() + 1 + (n / BITS_PER_WORD));
170	0	n %= BITS_PER_WORD;
171	0	}
172	0	if (n) {
173	0	auto& first = m_deque.front();
174	0	while (n) {
175	0	first.reset(m_pad_begin);
176	0	++m_pad_begin;
177	0	--n;
178	0	}
179	0	}
180	0	} Unexecuted instantiation: bitdeque<128>::erase_front(unsigned long) Unexecuted instantiation: bitdeque<32768>::erase_front(unsigned long)
181
182		/** Extend the container by n bits, adding at the beginning. */
183		void extend_front(size_type n)
184	0	{
185	0	if (n > static_cast<size_type>(m_pad_begin)) {
186	0	n -= m_pad_begin + 1;
187	0	m_pad_begin = BITS_PER_WORD - 1;
188	0	m_deque.insert(m_deque.begin(), 1 + (n / BITS_PER_WORD), {});
189	0	n %= BITS_PER_WORD;
190	0	}
191	0	m_pad_begin -= n;
192	0	}
193
194		/** Insert a sequence of falses anywhere in the container. */
195		void insert_zeroes(size_type before, size_type count)
196	0	{
197	0	size_type after = size() - before;
198	0	if (before < after) {
199	0	extend_front(count);
200	0	std::move(begin() + count, begin() + count + before, begin());
201	0	} else {
202	0	extend_back(count);
203	0	std::move_backward(begin() + before, begin() + before + after, end());
204	0	}
205	0	}
206
207		public:
208		/** Construct an empty container. */
209	0	explicit bitdeque() : m_pad_begin{0}, m_pad_end{0} {} Unexecuted instantiation: bitdeque<128>::bitdeque() Unexecuted instantiation: bitdeque<32768>::bitdeque()
210
211		/** Set the container equal to count times the value of val. */
212		void assign(size_type count, bool val)
213	0	{
214	0	m_deque.clear();
215	0	m_deque.resize(CeilDiv(count, size_type{BITS_PER_WORD}));
216	0	m_pad_begin = 0;
217	0	m_pad_end = 0;
218	0	if (val) {
219	0	for (auto& elem : m_deque) elem.flip();
220	0	}
221	0	if (count % BITS_PER_WORD) {
222	0	erase_back(BITS_PER_WORD - (count % BITS_PER_WORD));
223	0	}
224	0	}
225
226		/** Construct a container containing count times the value of val. */
227	0	bitdeque(size_type count, bool val) { assign(count, val); }
228
229		/** Construct a container containing count false values. */
230	0	explicit bitdeque(size_t count) { assign(count, false); }
231
232		/** Copy constructor. */
233		bitdeque(const bitdeque&) = default;
234
235		/** Move constructor. */
236		bitdeque(bitdeque&&) noexcept = default;
237
238		/** Copy assignment operator. */
239	0	bitdeque& operator=(const bitdeque& other) = default;
240
241		/** Move assignment operator. */
242	0	bitdeque& operator=(bitdeque&& other) noexcept = default;
243
244		// Iterator functions.
245	0	iterator begin() noexcept { return {m_deque.begin(), m_pad_begin}; } Unexecuted instantiation: bitdeque<128>::begin() Unexecuted instantiation: bitdeque<32768>::begin()
246	0	iterator end() noexcept { return iterator{m_deque.end(), 0} - m_pad_end; } Unexecuted instantiation: bitdeque<128>::end() Unexecuted instantiation: bitdeque<32768>::end()
247	0	const_iterator begin() const noexcept { return const_iterator{m_deque.cbegin(), m_pad_begin}; }
248	0	const_iterator cbegin() const noexcept { return const_iterator{m_deque.cbegin(), m_pad_begin}; }
249	0	const_iterator end() const noexcept { return const_iterator{m_deque.cend(), 0} - m_pad_end; }
250	0	const_iterator cend() const noexcept { return const_iterator{m_deque.cend(), 0} - m_pad_end; }
251	0	reverse_iterator rbegin() noexcept { return reverse_iterator{end()}; }
252	0	reverse_iterator rend() noexcept { return reverse_iterator{begin()}; }
253	0	const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator{cend()}; }
254	0	const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator{cend()}; }
255	0	const_reverse_iterator rend() const noexcept { return const_reverse_iterator{cbegin()}; }
256	0	const_reverse_iterator crend() const noexcept { return const_reverse_iterator{cbegin()}; }
257
258		/** Count the number of bits in the container. */
259	0	size_type size() const noexcept { return m_deque.size() * BITS_PER_WORD - m_pad_begin - m_pad_end; } Unexecuted instantiation: bitdeque<128>::size() const Unexecuted instantiation: bitdeque<32768>::size() const
260
261		/** Determine whether the container is empty. */
262		bool empty() const noexcept
263	0	{
264	0	return m_deque.size() == 0 \|\| (m_deque.size() == 1 && (m_pad_begin + m_pad_end == BITS_PER_WORD));
265	0	}
266
267		/** Return the maximum size of the container. */
268		size_type max_size() const noexcept
269	0	{
270	0	if (m_deque.max_size() < std::numeric_limits<difference_type>::max() / BITS_PER_WORD) {
271	0	return m_deque.max_size() * BITS_PER_WORD;
272	0	} else {
273	0	return std::numeric_limits<difference_type>::max();
274	0	}
275	0	}
276
277		/** Set the container equal to the bits in [first,last). */
278		template<typename It>
279		void assign(It first, It last)
280	0	{
281	0	size_type count = std::distance(first, last);
282	0	assign(count, false);
283	0	auto it = begin();
284	0	while (first != last) {
285	0	(it++) = (first++);
286	0	}
287	0	}
288
289		/** Set the container equal to the bits in ilist. */
290		void assign(std::initializer_list<bool> ilist)
291	0	{
292	0	assign(ilist.size(), false);
293	0	auto it = begin();
294	0	auto init = ilist.begin();
295	0	while (init != ilist.end()) {
296	0	(it++) = (init++);
297	0	}
298	0	}
299
300		/** Set the container equal to the bits in ilist. */
301		bitdeque& operator=(std::initializer_list<bool> ilist)
302	0	{
303	0	assign(ilist);
304	0	return *this;
305	0	}
306
307		/** Construct a container containing the bits in [first,last). */
308		template<typename It>
309	0	bitdeque(It first, It last) { assign(first, last); }
310
311		/** Construct a container containing the bits in ilist. */
312	0	bitdeque(std::initializer_list<bool> ilist) { assign(ilist); }
313
314		// Access an element of the container, with bounds checking.
315		reference at(size_type position)
316	0	{
317	0	if (position >= size()) throw std::out_of_range("bitdeque::at() out of range");
318	0	return begin()[position];
319	0	}
320		const_reference at(size_type position) const
321	0	{
322	0	if (position >= size()) throw std::out_of_range("bitdeque::at() out of range");
323	0	return cbegin()[position];
324	0	}
325
326		// Access elements of the container without bounds checking.
327	0	reference operator[](size_type position) { return begin()[position]; }
328		const_reference operator[](size_type position) const { return cbegin()[position]; }
329	0	reference front() { return *begin(); } Unexecuted instantiation: bitdeque<128>::front() Unexecuted instantiation: bitdeque<32768>::front()
330	0	const_reference front() const { return *cbegin(); }
331	0	reference back() { return end()[-1]; } Unexecuted instantiation: bitdeque<128>::back() Unexecuted instantiation: bitdeque<32768>::back()
332	0	const_reference back() const { return cend()[-1]; }
333
334		/** Release unused memory. */
335		void shrink_to_fit()
336		{
337		m_deque.shrink_to_fit();
338		}
339
340		/** Empty the container. */
341		void clear() noexcept
342	0	{
343	0	m_deque.clear();
344	0	m_pad_begin = m_pad_end = 0;
345	0	}
346
347		// Append an element to the container.
348		void push_back(bool val)
349	0	{
350	0	extend_back(1);
351	0	back() = val;
352	0	} Unexecuted instantiation: bitdeque<128>::push_back(bool) Unexecuted instantiation: bitdeque<32768>::push_back(bool)
353		reference emplace_back(bool val)
354		{
355		extend_back(1);
356		auto ref = back();
357		ref = val;
358		return ref;
359		}
360
361		// Prepend an element to the container.
362		void push_front(bool val)
363	0	{
364	0	extend_front(1);
365	0	front() = val;
366	0	}
367		reference emplace_front(bool val)
368		{
369		extend_front(1);
370		auto ref = front();
371		ref = val;
372		return ref;
373		}
374
375		// Remove the last element from the container.
376		void pop_back()
377	0	{
378	0	erase_back(1);
379	0	}
380
381		// Remove the first element from the container.
382		void pop_front()
383	0	{
384	0	erase_front(1);
385	0	} Unexecuted instantiation: bitdeque<128>::pop_front() Unexecuted instantiation: bitdeque<32768>::pop_front()
386
387		/** Resize the container. */
388		void resize(size_type n)
389	0	{
390	0	if (n < size()) {
391	0	erase_back(size() - n);
392	0	} else {
393	0	extend_back(n - size());
394	0	}
395	0	}
396
397		// Swap two containers.
398		void swap(bitdeque& other) noexcept
399	0	{
400	0	std::swap(m_deque, other.m_deque);
401	0	std::swap(m_pad_begin, other.m_pad_begin);
402	0	std::swap(m_pad_end, other.m_pad_end);
403	0	} Unexecuted instantiation: bitdeque<128>::swap(bitdeque<128>&) Unexecuted instantiation: bitdeque<32768>::swap(bitdeque<32768>&)
404	0	friend void swap(bitdeque& b1, bitdeque& b2) noexcept { b1.swap(b2); }
405
406		// Erase elements from the container.
407		iterator erase(const_iterator first, const_iterator last)
408	0	{
409	0	size_type before = std::distance(cbegin(), first);
410	0	size_type dist = std::distance(first, last);
411	0	size_type after = std::distance(last, cend());
412	0	if (before < after) {
413	0	std::move_backward(begin(), begin() + before, end() - after);
414	0	erase_front(dist);
415	0	return begin() + before;
416	0	} else {
417	0	std::move(end() - after, end(), begin() + before);
418	0	erase_back(dist);
419	0	return end() - after;
420	0	}
421	0	}
422
423		iterator erase(iterator first, iterator last) { return erase(const_iterator{first}, const_iterator{last}); }
424	0	iterator erase(const_iterator pos) { return erase(pos, pos + 1); }
425		iterator erase(iterator pos) { return erase(const_iterator{pos}, const_iterator{pos} + 1); }
426
427		// Insert elements into the container.
428		iterator insert(const_iterator pos, bool val)
429	0	{
430	0	size_type before = pos - cbegin();
431	0	insert_zeroes(before, 1);
432	0	auto it = begin() + before;
433	0	*it = val;
434	0	return it;
435	0	}
436
437	0	iterator emplace(const_iterator pos, bool val) { return insert(pos, val); }
438
439		iterator insert(const_iterator pos, size_type count, bool val)
440	0	{
441	0	size_type before = pos - cbegin();
442	0	insert_zeroes(before, count);
443	0	auto it_begin = begin() + before;
444	0	auto it = it_begin;
445	0	auto it_end = it + count;
446	0	while (it != it_end) *(it++) = val;
447	0	return it_begin;
448	0	}
449
450		template<typename It>
451		iterator insert(const_iterator pos, It first, It last)
452	0	{
453	0	size_type before = pos - cbegin();
454	0	size_type count = std::distance(first, last);
455	0	insert_zeroes(before, count);
456	0	auto it_begin = begin() + before;
457	0	auto it = it_begin;
458	0	while (first != last) {
459	0	(it++) = (first++);
460	0	}
461	0	return it_begin;
462	0	}
463		};
464
465		#endif // BITCOIN_UTIL_BITDEQUE_H