dynarmic/externals/robin-map/include/tsl/robin_set.h

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/**
* MIT License
*
* Copyright (c) 2017 Thibaut Goetghebuer-Planchon <tessil@gmx.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef TSL_ROBIN_SET_H
#define TSL_ROBIN_SET_H
#include <cstddef>
#include <functional>
#include <initializer_list>
#include <memory>
#include <type_traits>
#include <utility>
#include "robin_hash.h"
namespace tsl {
/**
* Implementation of a hash set using open-addressing and the robin hood hashing algorithm with backward shift deletion.
*
* For operations modifying the hash set (insert, erase, rehash, ...), the strong exception guarantee
* is only guaranteed when the expression `std::is_nothrow_swappable<Key>::value &&
* std::is_nothrow_move_constructible<Key>::value` is true, otherwise if an exception
* is thrown during the swap or the move, the hash set may end up in a undefined state. Per the standard
* a `Key` with a noexcept copy constructor and no move constructor also satisfies the
* `std::is_nothrow_move_constructible<Key>::value` criterion (and will thus guarantee the
* strong exception for the set).
*
* When `StoreHash` is true, 32 bits of the hash are stored alongside the values. It can improve
* the performance during lookups if the `KeyEqual` function takes time (or engenders a cache-miss for example)
* as we then compare the stored hashes before comparing the keys. When `tsl::rh::power_of_two_growth_policy` is used
* as `GrowthPolicy`, it may also speed-up the rehash process as we can avoid to recalculate the hash.
* When it is detected that storing the hash will not incur any memory penalty due to alignment (i.e.
* `sizeof(tsl::detail_robin_hash::bucket_entry<ValueType, true>) ==
* sizeof(tsl::detail_robin_hash::bucket_entry<ValueType, false>)`) and `tsl::rh::power_of_two_growth_policy` is
* used, the hash will be stored even if `StoreHash` is false so that we can speed-up the rehash (but it will
* not be used on lookups unless `StoreHash` is true).
*
* `GrowthPolicy` defines how the set grows and consequently how a hash value is mapped to a bucket.
* By default the set uses `tsl::rh::power_of_two_growth_policy`. This policy keeps the number of buckets
* to a power of two and uses a mask to set the hash to a bucket instead of the slow modulo.
* Other growth policies are available and you may define your own growth policy,
* check `tsl::rh::power_of_two_growth_policy` for the interface.
*
* `Key` must be swappable.
*
* `Key` must be copy and/or move constructible.
*
* If the destructor of `Key` throws an exception, the behaviour of the class is undefined.
*
* Iterators invalidation:
* - clear, operator=, reserve, rehash: always invalidate the iterators.
* - insert, emplace, emplace_hint, operator[]: if there is an effective insert, invalidate the iterators.
* - erase: always invalidate the iterators.
*/
template<class Key,
class Hash = std::hash<Key>,
class KeyEqual = std::equal_to<Key>,
class Allocator = std::allocator<Key>,
bool StoreHash = false,
class GrowthPolicy = tsl::rh::power_of_two_growth_policy<2>>
class robin_set {
private:
template<typename U>
using has_is_transparent = tsl::detail_robin_hash::has_is_transparent<U>;
class KeySelect {
public:
using key_type = Key;
const key_type& operator()(const Key& key) const noexcept {
return key;
}
key_type& operator()(Key& key) noexcept {
return key;
}
};
using ht = detail_robin_hash::robin_hash<Key, KeySelect, void,
Hash, KeyEqual, Allocator, StoreHash, GrowthPolicy>;
public:
using key_type = typename ht::key_type;
using value_type = typename ht::value_type;
using size_type = typename ht::size_type;
using difference_type = typename ht::difference_type;
using hasher = typename ht::hasher;
using key_equal = typename ht::key_equal;
using allocator_type = typename ht::allocator_type;
using reference = typename ht::reference;
using const_reference = typename ht::const_reference;
using pointer = typename ht::pointer;
using const_pointer = typename ht::const_pointer;
using iterator = typename ht::iterator;
using const_iterator = typename ht::const_iterator;
/*
* Constructors
*/
robin_set(): robin_set(ht::DEFAULT_INIT_BUCKETS_SIZE) {
}
explicit robin_set(size_type bucket_count,
const Hash& hash = Hash(),
const KeyEqual& equal = KeyEqual(),
const Allocator& alloc = Allocator()):
m_ht(bucket_count, hash, equal, alloc)
{
}
robin_set(size_type bucket_count,
const Allocator& alloc): robin_set(bucket_count, Hash(), KeyEqual(), alloc)
{
}
robin_set(size_type bucket_count,
const Hash& hash,
const Allocator& alloc): robin_set(bucket_count, hash, KeyEqual(), alloc)
{
}
explicit robin_set(const Allocator& alloc): robin_set(ht::DEFAULT_INIT_BUCKETS_SIZE, alloc) {
}
template<class InputIt>
robin_set(InputIt first, InputIt last,
size_type bucket_count = ht::DEFAULT_INIT_BUCKETS_SIZE,
const Hash& hash = Hash(),
const KeyEqual& equal = KeyEqual(),
const Allocator& alloc = Allocator()): robin_set(bucket_count, hash, equal, alloc)
{
insert(first, last);
}
template<class InputIt>
robin_set(InputIt first, InputIt last,
size_type bucket_count,
const Allocator& alloc): robin_set(first, last, bucket_count, Hash(), KeyEqual(), alloc)
{
}
template<class InputIt>
robin_set(InputIt first, InputIt last,
size_type bucket_count,
const Hash& hash,
const Allocator& alloc): robin_set(first, last, bucket_count, hash, KeyEqual(), alloc)
{
}
robin_set(std::initializer_list<value_type> init,
size_type bucket_count = ht::DEFAULT_INIT_BUCKETS_SIZE,
const Hash& hash = Hash(),
const KeyEqual& equal = KeyEqual(),
const Allocator& alloc = Allocator()):
robin_set(init.begin(), init.end(), bucket_count, hash, equal, alloc)
{
}
robin_set(std::initializer_list<value_type> init,
size_type bucket_count,
const Allocator& alloc):
robin_set(init.begin(), init.end(), bucket_count, Hash(), KeyEqual(), alloc)
{
}
robin_set(std::initializer_list<value_type> init,
size_type bucket_count,
const Hash& hash,
const Allocator& alloc):
robin_set(init.begin(), init.end(), bucket_count, hash, KeyEqual(), alloc)
{
}
robin_set& operator=(std::initializer_list<value_type> ilist) {
m_ht.clear();
m_ht.reserve(ilist.size());
m_ht.insert(ilist.begin(), ilist.end());
return *this;
}
allocator_type get_allocator() const { return m_ht.get_allocator(); }
/*
* Iterators
*/
iterator begin() noexcept { return m_ht.begin(); }
const_iterator begin() const noexcept { return m_ht.begin(); }
const_iterator cbegin() const noexcept { return m_ht.cbegin(); }
iterator end() noexcept { return m_ht.end(); }
const_iterator end() const noexcept { return m_ht.end(); }
const_iterator cend() const noexcept { return m_ht.cend(); }
/*
* Capacity
*/
bool empty() const noexcept { return m_ht.empty(); }
size_type size() const noexcept { return m_ht.size(); }
size_type max_size() const noexcept { return m_ht.max_size(); }
/*
* Modifiers
*/
void clear() noexcept { m_ht.clear(); }
std::pair<iterator, bool> insert(const value_type& value) {
return m_ht.insert(value);
}
std::pair<iterator, bool> insert(value_type&& value) {
return m_ht.insert(std::move(value));
}
iterator insert(const_iterator hint, const value_type& value) {
return m_ht.insert_hint(hint, value);
}
iterator insert(const_iterator hint, value_type&& value) {
return m_ht.insert_hint(hint, std::move(value));
}
template<class InputIt>
void insert(InputIt first, InputIt last) {
m_ht.insert(first, last);
}
void insert(std::initializer_list<value_type> ilist) {
m_ht.insert(ilist.begin(), ilist.end());
}
/**
* Due to the way elements are stored, emplace will need to move or copy the key-value once.
* The method is equivalent to insert(value_type(std::forward<Args>(args)...));
*
* Mainly here for compatibility with the std::unordered_map interface.
*/
template<class... Args>
std::pair<iterator, bool> emplace(Args&&... args) {
return m_ht.emplace(std::forward<Args>(args)...);
}
/**
* Due to the way elements are stored, emplace_hint will need to move or copy the key-value once.
* The method is equivalent to insert(hint, value_type(std::forward<Args>(args)...));
*
* Mainly here for compatibility with the std::unordered_map interface.
*/
template<class... Args>
iterator emplace_hint(const_iterator hint, Args&&... args) {
return m_ht.emplace_hint(hint, std::forward<Args>(args)...);
}
iterator erase(iterator pos) { return m_ht.erase(pos); }
iterator erase(const_iterator pos) { return m_ht.erase(pos); }
iterator erase(const_iterator first, const_iterator last) { return m_ht.erase(first, last); }
size_type erase(const key_type& key) { return m_ht.erase(key); }
/**
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup to the value if you already have the hash.
*/
size_type erase(const key_type& key, std::size_t precalculated_hash) {
return m_ht.erase(key, precalculated_hash);
}
/**
* This overload only participates in the overload resolution if the typedef KeyEqual::is_transparent exists.
* If so, K must be hashable and comparable to Key.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
size_type erase(const K& key) { return m_ht.erase(key); }
/**
* @copydoc erase(const K& key)
*
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup to the value if you already have the hash.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
size_type erase(const K& key, std::size_t precalculated_hash) {
return m_ht.erase(key, precalculated_hash);
}
void swap(robin_set& other) { other.m_ht.swap(m_ht); }
/*
* Lookup
*/
size_type count(const Key& key) const { return m_ht.count(key); }
/**
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
size_type count(const Key& key, std::size_t precalculated_hash) const { return m_ht.count(key, precalculated_hash); }
/**
* This overload only participates in the overload resolution if the typedef KeyEqual::is_transparent exists.
* If so, K must be hashable and comparable to Key.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
size_type count(const K& key) const { return m_ht.count(key); }
/**
* @copydoc count(const K& key) const
*
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
size_type count(const K& key, std::size_t precalculated_hash) const { return m_ht.count(key, precalculated_hash); }
iterator find(const Key& key) { return m_ht.find(key); }
/**
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
iterator find(const Key& key, std::size_t precalculated_hash) { return m_ht.find(key, precalculated_hash); }
const_iterator find(const Key& key) const { return m_ht.find(key); }
/**
* @copydoc find(const Key& key, std::size_t precalculated_hash)
*/
const_iterator find(const Key& key, std::size_t precalculated_hash) const { return m_ht.find(key, precalculated_hash); }
/**
* This overload only participates in the overload resolution if the typedef KeyEqual::is_transparent exists.
* If so, K must be hashable and comparable to Key.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
iterator find(const K& key) { return m_ht.find(key); }
/**
* @copydoc find(const K& key)
*
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
iterator find(const K& key, std::size_t precalculated_hash) { return m_ht.find(key, precalculated_hash); }
/**
* @copydoc find(const K& key)
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
const_iterator find(const K& key) const { return m_ht.find(key); }
/**
* @copydoc find(const K& key)
*
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
const_iterator find(const K& key, std::size_t precalculated_hash) const { return m_ht.find(key, precalculated_hash); }
bool contains(const Key& key) const { return m_ht.contains(key); }
/**
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
bool contains(const Key& key, std::size_t precalculated_hash) const {
return m_ht.contains(key, precalculated_hash);
}
/**
* This overload only participates in the overload resolution if the typedef KeyEqual::is_transparent exists.
* If so, K must be hashable and comparable to Key.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
bool contains(const K& key) const { return m_ht.contains(key); }
/**
* @copydoc contains(const K& key) const
*
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
bool contains(const K& key, std::size_t precalculated_hash) const {
return m_ht.contains(key, precalculated_hash);
}
std::pair<iterator, iterator> equal_range(const Key& key) { return m_ht.equal_range(key); }
/**
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
std::pair<iterator, iterator> equal_range(const Key& key, std::size_t precalculated_hash) {
return m_ht.equal_range(key, precalculated_hash);
}
std::pair<const_iterator, const_iterator> equal_range(const Key& key) const { return m_ht.equal_range(key); }
/**
* @copydoc equal_range(const Key& key, std::size_t precalculated_hash)
*/
std::pair<const_iterator, const_iterator> equal_range(const Key& key, std::size_t precalculated_hash) const {
return m_ht.equal_range(key, precalculated_hash);
}
/**
* This overload only participates in the overload resolution if the typedef KeyEqual::is_transparent exists.
* If so, K must be hashable and comparable to Key.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
std::pair<iterator, iterator> equal_range(const K& key) { return m_ht.equal_range(key); }
/**
* @copydoc equal_range(const K& key)
*
* Use the hash value 'precalculated_hash' instead of hashing the key. The hash value should be the same
* as hash_function()(key). Useful to speed-up the lookup if you already have the hash.
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
std::pair<iterator, iterator> equal_range(const K& key, std::size_t precalculated_hash) {
return m_ht.equal_range(key, precalculated_hash);
}
/**
* @copydoc equal_range(const K& key)
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
std::pair<const_iterator, const_iterator> equal_range(const K& key) const { return m_ht.equal_range(key); }
/**
* @copydoc equal_range(const K& key, std::size_t precalculated_hash)
*/
template<class K, class KE = KeyEqual, typename std::enable_if<has_is_transparent<KE>::value>::type* = nullptr>
std::pair<const_iterator, const_iterator> equal_range(const K& key, std::size_t precalculated_hash) const {
return m_ht.equal_range(key, precalculated_hash);
}
/*
* Bucket interface
*/
size_type bucket_count() const { return m_ht.bucket_count(); }
size_type max_bucket_count() const { return m_ht.max_bucket_count(); }
/*
* Hash policy
*/
float load_factor() const { return m_ht.load_factor(); }
float min_load_factor() const { return m_ht.min_load_factor(); }
float max_load_factor() const { return m_ht.max_load_factor(); }
/**
* Set the `min_load_factor` to `ml`. When the `load_factor` of the set goes
* below `min_load_factor` after some erase operations, the set will be
* shrunk when an insertion occurs. The erase method itself never shrinks
* the set.
*
* The default value of `min_load_factor` is 0.0f, the set never shrinks by default.
*/
void min_load_factor(float ml) { m_ht.min_load_factor(ml); }
void max_load_factor(float ml) { m_ht.max_load_factor(ml); }
void rehash(size_type count) { m_ht.rehash(count); }
void reserve(size_type count) { m_ht.reserve(count); }
/*
* Observers
*/
hasher hash_function() const { return m_ht.hash_function(); }
key_equal key_eq() const { return m_ht.key_eq(); }
/*
* Other
*/
/**
* Convert a const_iterator to an iterator.
*/
iterator mutable_iterator(const_iterator pos) {
return m_ht.mutable_iterator(pos);
}
friend bool operator==(const robin_set& lhs, const robin_set& rhs) {
if(lhs.size() != rhs.size()) {
return false;
}
for(const auto& element_lhs: lhs) {
const auto it_element_rhs = rhs.find(element_lhs);
if(it_element_rhs == rhs.cend()) {
return false;
}
}
return true;
}
friend bool operator!=(const robin_set& lhs, const robin_set& rhs) {
return !operator==(lhs, rhs);
}
friend void swap(robin_set& lhs, robin_set& rhs) {
lhs.swap(rhs);
}
private:
ht m_ht;
};
/**
* Same as `tsl::robin_set<Key, Hash, KeyEqual, Allocator, StoreHash, tsl::rh::prime_growth_policy>`.
*/
template<class Key,
class Hash = std::hash<Key>,
class KeyEqual = std::equal_to<Key>,
class Allocator = std::allocator<Key>,
bool StoreHash = false>
using robin_pg_set = robin_set<Key, Hash, KeyEqual, Allocator, StoreHash, tsl::rh::prime_growth_policy>;
} // end namespace tsl
#endif