| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef ART_RUNTIME_BASE_HASH_SET_H_ |
| #define ART_RUNTIME_BASE_HASH_SET_H_ |
| |
| #include <functional> |
| #include <iterator> |
| #include <memory> |
| #include <stdint.h> |
| #include <utility> |
| |
| #include "bit_utils.h" |
| #include "logging.h" |
| |
| namespace art { |
| |
| // Returns true if an item is empty. |
| template <class T> |
| class DefaultEmptyFn { |
| public: |
| void MakeEmpty(T& item) const { |
| item = T(); |
| } |
| bool IsEmpty(const T& item) const { |
| return item == T(); |
| } |
| }; |
| |
| template <class T> |
| class DefaultEmptyFn<T*> { |
| public: |
| void MakeEmpty(T*& item) const { |
| item = nullptr; |
| } |
| bool IsEmpty(T* const& item) const { |
| return item == nullptr; |
| } |
| }; |
| |
| // Low memory version of a hash set, uses less memory than std::unordered_set since elements aren't |
| // boxed. Uses linear probing to resolve collisions. |
| // EmptyFn needs to implement two functions MakeEmpty(T& item) and IsEmpty(const T& item). |
| // TODO: We could get rid of this requirement by using a bitmap, though maybe this would be slower |
| // and more complicated. |
| template <class T, class EmptyFn = DefaultEmptyFn<T>, class HashFn = std::hash<T>, |
| class Pred = std::equal_to<T>, class Alloc = std::allocator<T>> |
| class HashSet { |
| template <class Elem, class HashSetType> |
| class BaseIterator : std::iterator<std::forward_iterator_tag, Elem> { |
| public: |
| BaseIterator(const BaseIterator&) = default; |
| BaseIterator(BaseIterator&&) = default; |
| BaseIterator(HashSetType* hash_set, size_t index) : index_(index), hash_set_(hash_set) { |
| } |
| BaseIterator& operator=(const BaseIterator&) = default; |
| BaseIterator& operator=(BaseIterator&&) = default; |
| |
| bool operator==(const BaseIterator& other) const { |
| return hash_set_ == other.hash_set_ && this->index_ == other.index_; |
| } |
| |
| bool operator!=(const BaseIterator& other) const { |
| return !(*this == other); |
| } |
| |
| BaseIterator operator++() { // Value after modification. |
| this->index_ = this->NextNonEmptySlot(this->index_, hash_set_); |
| return *this; |
| } |
| |
| BaseIterator operator++(int) { |
| BaseIterator temp = *this; |
| this->index_ = this->NextNonEmptySlot(this->index_, hash_set_); |
| return temp; |
| } |
| |
| Elem& operator*() const { |
| DCHECK(!hash_set_->IsFreeSlot(this->index_)); |
| return hash_set_->ElementForIndex(this->index_); |
| } |
| |
| Elem* operator->() const { |
| return &**this; |
| } |
| |
| // TODO: Operator -- --(int) (and use std::bidirectional_iterator_tag) |
| |
| private: |
| size_t index_; |
| HashSetType* hash_set_; |
| |
| size_t NextNonEmptySlot(size_t index, const HashSet* hash_set) const { |
| const size_t num_buckets = hash_set->NumBuckets(); |
| DCHECK_LT(index, num_buckets); |
| do { |
| ++index; |
| } while (index < num_buckets && hash_set->IsFreeSlot(index)); |
| return index; |
| } |
| |
| friend class HashSet; |
| }; |
| |
| public: |
| using value_type = T; |
| using allocator_type = Alloc; |
| using reference = T&; |
| using const_reference = const T&; |
| using pointer = T*; |
| using const_pointer = const T*; |
| using iterator = BaseIterator<T, HashSet>; |
| using const_iterator = BaseIterator<const T, const HashSet>; |
| using size_type = size_t; |
| using difference_type = ptrdiff_t; |
| |
| static constexpr double kDefaultMinLoadFactor = 0.4; |
| static constexpr double kDefaultMaxLoadFactor = 0.7; |
| static constexpr size_t kMinBuckets = 1000; |
| |
| // If we don't own the data, this will create a new array which owns the data. |
| void Clear() { |
| DeallocateStorage(); |
| num_elements_ = 0; |
| elements_until_expand_ = 0; |
| } |
| |
| HashSet() : HashSet(kDefaultMinLoadFactor, kDefaultMaxLoadFactor) {} |
| |
| HashSet(double min_load_factor, double max_load_factor) noexcept |
| : num_elements_(0u), |
| num_buckets_(0u), |
| elements_until_expand_(0u), |
| owns_data_(false), |
| data_(nullptr), |
| min_load_factor_(min_load_factor), |
| max_load_factor_(max_load_factor) { |
| DCHECK_GT(min_load_factor, 0.0); |
| DCHECK_LT(max_load_factor, 1.0); |
| } |
| |
| explicit HashSet(const allocator_type& alloc) noexcept |
| : allocfn_(alloc), |
| hashfn_(), |
| emptyfn_(), |
| pred_(), |
| num_elements_(0u), |
| num_buckets_(0u), |
| elements_until_expand_(0u), |
| owns_data_(false), |
| data_(nullptr), |
| min_load_factor_(kDefaultMinLoadFactor), |
| max_load_factor_(kDefaultMaxLoadFactor) { |
| } |
| |
| HashSet(const HashSet& other) noexcept |
| : allocfn_(other.allocfn_), |
| hashfn_(other.hashfn_), |
| emptyfn_(other.emptyfn_), |
| pred_(other.pred_), |
| num_elements_(other.num_elements_), |
| num_buckets_(0), |
| elements_until_expand_(other.elements_until_expand_), |
| owns_data_(false), |
| data_(nullptr), |
| min_load_factor_(other.min_load_factor_), |
| max_load_factor_(other.max_load_factor_) { |
| AllocateStorage(other.NumBuckets()); |
| for (size_t i = 0; i < num_buckets_; ++i) { |
| ElementForIndex(i) = other.data_[i]; |
| } |
| } |
| |
| // noexcept required so that the move constructor is used instead of copy constructor. |
| // b/27860101 |
| HashSet(HashSet&& other) noexcept |
| : allocfn_(std::move(other.allocfn_)), |
| hashfn_(std::move(other.hashfn_)), |
| emptyfn_(std::move(other.emptyfn_)), |
| pred_(std::move(other.pred_)), |
| num_elements_(other.num_elements_), |
| num_buckets_(other.num_buckets_), |
| elements_until_expand_(other.elements_until_expand_), |
| owns_data_(other.owns_data_), |
| data_(other.data_), |
| min_load_factor_(other.min_load_factor_), |
| max_load_factor_(other.max_load_factor_) { |
| other.num_elements_ = 0u; |
| other.num_buckets_ = 0u; |
| other.elements_until_expand_ = 0u; |
| other.owns_data_ = false; |
| other.data_ = nullptr; |
| } |
| |
| // Construct from existing data. |
| // Read from a block of memory, if make_copy_of_data is false, then data_ points to within the |
| // passed in ptr_. |
| HashSet(const uint8_t* ptr, bool make_copy_of_data, size_t* read_count) noexcept { |
| uint64_t temp; |
| size_t offset = 0; |
| offset = ReadFromBytes(ptr, offset, &temp); |
| num_elements_ = static_cast<uint64_t>(temp); |
| offset = ReadFromBytes(ptr, offset, &temp); |
| num_buckets_ = static_cast<uint64_t>(temp); |
| CHECK_LE(num_elements_, num_buckets_); |
| offset = ReadFromBytes(ptr, offset, &temp); |
| elements_until_expand_ = static_cast<uint64_t>(temp); |
| offset = ReadFromBytes(ptr, offset, &min_load_factor_); |
| offset = ReadFromBytes(ptr, offset, &max_load_factor_); |
| if (!make_copy_of_data) { |
| owns_data_ = false; |
| data_ = const_cast<T*>(reinterpret_cast<const T*>(ptr + offset)); |
| offset += sizeof(*data_) * num_buckets_; |
| } else { |
| AllocateStorage(num_buckets_); |
| // Write elements, not that this may not be safe for cross compilation if the elements are |
| // pointer sized. |
| for (size_t i = 0; i < num_buckets_; ++i) { |
| offset = ReadFromBytes(ptr, offset, &data_[i]); |
| } |
| } |
| // Caller responsible for aligning. |
| *read_count = offset; |
| } |
| |
| // Returns how large the table is after being written. If target is null, then no writing happens |
| // but the size is still returned. Target must be 8 byte aligned. |
| size_t WriteToMemory(uint8_t* ptr) const { |
| size_t offset = 0; |
| offset = WriteToBytes(ptr, offset, static_cast<uint64_t>(num_elements_)); |
| offset = WriteToBytes(ptr, offset, static_cast<uint64_t>(num_buckets_)); |
| offset = WriteToBytes(ptr, offset, static_cast<uint64_t>(elements_until_expand_)); |
| offset = WriteToBytes(ptr, offset, min_load_factor_); |
| offset = WriteToBytes(ptr, offset, max_load_factor_); |
| // Write elements, not that this may not be safe for cross compilation if the elements are |
| // pointer sized. |
| for (size_t i = 0; i < num_buckets_; ++i) { |
| offset = WriteToBytes(ptr, offset, data_[i]); |
| } |
| // Caller responsible for aligning. |
| return offset; |
| } |
| |
| ~HashSet() { |
| DeallocateStorage(); |
| } |
| |
| HashSet& operator=(HashSet&& other) noexcept { |
| HashSet(std::move(other)).swap(*this); |
| return *this; |
| } |
| |
| HashSet& operator=(const HashSet& other) noexcept { |
| HashSet(other).swap(*this); // NOLINT(runtime/explicit) - a case of lint gone mad. |
| return *this; |
| } |
| |
| // Lower case for c++11 for each. |
| iterator begin() { |
| iterator ret(this, 0); |
| if (num_buckets_ != 0 && IsFreeSlot(ret.index_)) { |
| ++ret; // Skip all the empty slots. |
| } |
| return ret; |
| } |
| |
| // Lower case for c++11 for each. const version. |
| const_iterator begin() const { |
| const_iterator ret(this, 0); |
| if (num_buckets_ != 0 && IsFreeSlot(ret.index_)) { |
| ++ret; // Skip all the empty slots. |
| } |
| return ret; |
| } |
| |
| // Lower case for c++11 for each. |
| iterator end() { |
| return iterator(this, NumBuckets()); |
| } |
| |
| // Lower case for c++11 for each. const version. |
| const_iterator end() const { |
| return const_iterator(this, NumBuckets()); |
| } |
| |
| bool Empty() { |
| return Size() == 0; |
| } |
| |
| // Return true if the hash set has ownership of the underlying data. |
| bool OwnsData() const { |
| return owns_data_; |
| } |
| |
| // Erase algorithm: |
| // Make an empty slot where the iterator is pointing. |
| // Scan forwards until we hit another empty slot. |
| // If an element in between doesn't rehash to the range from the current empty slot to the |
| // iterator. It must be before the empty slot, in that case we can move it to the empty slot |
| // and set the empty slot to be the location we just moved from. |
| // Relies on maintaining the invariant that there's no empty slots from the 'ideal' index of an |
| // element to its actual location/index. |
| iterator Erase(iterator it) { |
| // empty_index is the index that will become empty. |
| size_t empty_index = it.index_; |
| DCHECK(!IsFreeSlot(empty_index)); |
| size_t next_index = empty_index; |
| bool filled = false; // True if we filled the empty index. |
| while (true) { |
| next_index = NextIndex(next_index); |
| T& next_element = ElementForIndex(next_index); |
| // If the next element is empty, we are done. Make sure to clear the current empty index. |
| if (emptyfn_.IsEmpty(next_element)) { |
| emptyfn_.MakeEmpty(ElementForIndex(empty_index)); |
| break; |
| } |
| // Otherwise try to see if the next element can fill the current empty index. |
| const size_t next_hash = hashfn_(next_element); |
| // Calculate the ideal index, if it is within empty_index + 1 to next_index then there is |
| // nothing we can do. |
| size_t next_ideal_index = IndexForHash(next_hash); |
| // Loop around if needed for our check. |
| size_t unwrapped_next_index = next_index; |
| if (unwrapped_next_index < empty_index) { |
| unwrapped_next_index += NumBuckets(); |
| } |
| // Loop around if needed for our check. |
| size_t unwrapped_next_ideal_index = next_ideal_index; |
| if (unwrapped_next_ideal_index < empty_index) { |
| unwrapped_next_ideal_index += NumBuckets(); |
| } |
| if (unwrapped_next_ideal_index <= empty_index || |
| unwrapped_next_ideal_index > unwrapped_next_index) { |
| // If the target index isn't within our current range it must have been probed from before |
| // the empty index. |
| ElementForIndex(empty_index) = std::move(next_element); |
| filled = true; // TODO: Optimize |
| empty_index = next_index; |
| } |
| } |
| --num_elements_; |
| // If we didn't fill the slot then we need go to the next non free slot. |
| if (!filled) { |
| ++it; |
| } |
| return it; |
| } |
| |
| // Find an element, returns end() if not found. |
| // Allows custom key (K) types, example of when this is useful: |
| // Set of Class* sorted by name, want to find a class with a name but can't allocate a dummy |
| // object in the heap for performance solution. |
| template <typename K> |
| iterator Find(const K& key) { |
| return FindWithHash(key, hashfn_(key)); |
| } |
| |
| template <typename K> |
| const_iterator Find(const K& key) const { |
| return FindWithHash(key, hashfn_(key)); |
| } |
| |
| template <typename K> |
| iterator FindWithHash(const K& key, size_t hash) { |
| return iterator(this, FindIndex(key, hash)); |
| } |
| |
| template <typename K> |
| const_iterator FindWithHash(const K& key, size_t hash) const { |
| return const_iterator(this, FindIndex(key, hash)); |
| } |
| |
| // Insert an element, allows duplicates. |
| void Insert(const T& element) { |
| InsertWithHash(element, hashfn_(element)); |
| } |
| |
| void InsertWithHash(const T& element, size_t hash) { |
| DCHECK_EQ(hash, hashfn_(element)); |
| if (num_elements_ >= elements_until_expand_) { |
| Expand(); |
| DCHECK_LT(num_elements_, elements_until_expand_); |
| } |
| const size_t index = FirstAvailableSlot(IndexForHash(hash)); |
| data_[index] = element; |
| ++num_elements_; |
| } |
| |
| size_t Size() const { |
| return num_elements_; |
| } |
| |
| void swap(HashSet& other) { |
| // Use argument-dependent lookup with fall-back to std::swap() for function objects. |
| using std::swap; |
| swap(allocfn_, other.allocfn_); |
| swap(hashfn_, other.hashfn_); |
| swap(emptyfn_, other.emptyfn_); |
| swap(pred_, other.pred_); |
| std::swap(data_, other.data_); |
| std::swap(num_buckets_, other.num_buckets_); |
| std::swap(num_elements_, other.num_elements_); |
| std::swap(elements_until_expand_, other.elements_until_expand_); |
| std::swap(min_load_factor_, other.min_load_factor_); |
| std::swap(max_load_factor_, other.max_load_factor_); |
| std::swap(owns_data_, other.owns_data_); |
| } |
| |
| allocator_type get_allocator() const { |
| return allocfn_; |
| } |
| |
| void ShrinkToMaximumLoad() { |
| Resize(Size() / max_load_factor_); |
| } |
| |
| // Reserve enough room to insert until Size() == num_elements without requiring to grow the hash |
| // set. No-op if the hash set is already large enough to do this. |
| void Reserve(size_t num_elements) { |
| size_t num_buckets = num_elements / max_load_factor_; |
| // Deal with rounding errors. Add one for rounding. |
| while (static_cast<size_t>(num_buckets * max_load_factor_) <= num_elements + 1u) { |
| ++num_buckets; |
| } |
| if (num_buckets > NumBuckets()) { |
| Resize(num_buckets); |
| } |
| } |
| |
| // To distance that inserted elements were probed. Used for measuring how good hash functions |
| // are. |
| size_t TotalProbeDistance() const { |
| size_t total = 0; |
| for (size_t i = 0; i < NumBuckets(); ++i) { |
| const T& element = ElementForIndex(i); |
| if (!emptyfn_.IsEmpty(element)) { |
| size_t ideal_location = IndexForHash(hashfn_(element)); |
| if (ideal_location > i) { |
| total += i + NumBuckets() - ideal_location; |
| } else { |
| total += i - ideal_location; |
| } |
| } |
| } |
| return total; |
| } |
| |
| // Calculate the current load factor and return it. |
| double CalculateLoadFactor() const { |
| return static_cast<double>(Size()) / static_cast<double>(NumBuckets()); |
| } |
| |
| // Make sure that everything reinserts in the right spot. Returns the number of errors. |
| size_t Verify() NO_THREAD_SAFETY_ANALYSIS { |
| size_t errors = 0; |
| for (size_t i = 0; i < num_buckets_; ++i) { |
| T& element = data_[i]; |
| if (!emptyfn_.IsEmpty(element)) { |
| T temp; |
| emptyfn_.MakeEmpty(temp); |
| std::swap(temp, element); |
| size_t first_slot = FirstAvailableSlot(IndexForHash(hashfn_(temp))); |
| if (i != first_slot) { |
| LOG(ERROR) << "Element " << i << " should be in slot " << first_slot; |
| ++errors; |
| } |
| std::swap(temp, element); |
| } |
| } |
| return errors; |
| } |
| |
| double GetMinLoadFactor() const { |
| return min_load_factor_; |
| } |
| |
| double GetMaxLoadFactor() const { |
| return max_load_factor_; |
| } |
| |
| // Change the load factor of the hash set. If the current load factor is greater than the max |
| // specified, then we resize the hash table storage. |
| void SetLoadFactor(double min_load_factor, double max_load_factor) { |
| DCHECK_LT(min_load_factor, max_load_factor); |
| DCHECK_GT(min_load_factor, 0.0); |
| DCHECK_LT(max_load_factor, 1.0); |
| min_load_factor_ = min_load_factor; |
| max_load_factor_ = max_load_factor; |
| elements_until_expand_ = NumBuckets() * max_load_factor_; |
| // If the current load factor isn't in the range, then resize to the mean of the minimum and |
| // maximum load factor. |
| const double load_factor = CalculateLoadFactor(); |
| if (load_factor > max_load_factor_) { |
| Resize(Size() / ((min_load_factor_ + max_load_factor_) * 0.5)); |
| } |
| } |
| |
| // The hash set expands when Size() reaches ElementsUntilExpand(). |
| size_t ElementsUntilExpand() const { |
| return elements_until_expand_; |
| } |
| |
| size_t NumBuckets() const { |
| return num_buckets_; |
| } |
| |
| private: |
| T& ElementForIndex(size_t index) { |
| DCHECK_LT(index, NumBuckets()); |
| DCHECK(data_ != nullptr); |
| return data_[index]; |
| } |
| |
| const T& ElementForIndex(size_t index) const { |
| DCHECK_LT(index, NumBuckets()); |
| DCHECK(data_ != nullptr); |
| return data_[index]; |
| } |
| |
| size_t IndexForHash(size_t hash) const { |
| // Protect against undefined behavior (division by zero). |
| if (UNLIKELY(num_buckets_ == 0)) { |
| return 0; |
| } |
| return hash % num_buckets_; |
| } |
| |
| size_t NextIndex(size_t index) const { |
| if (UNLIKELY(++index >= num_buckets_)) { |
| DCHECK_EQ(index, NumBuckets()); |
| return 0; |
| } |
| return index; |
| } |
| |
| // Find the hash table slot for an element, or return NumBuckets() if not found. |
| // This value for not found is important so that iterator(this, FindIndex(...)) == end(). |
| template <typename K> |
| size_t FindIndex(const K& element, size_t hash) const { |
| // Guard against failing to get an element for a non-existing index. |
| if (UNLIKELY(NumBuckets() == 0)) { |
| return 0; |
| } |
| DCHECK_EQ(hashfn_(element), hash); |
| size_t index = IndexForHash(hash); |
| while (true) { |
| const T& slot = ElementForIndex(index); |
| if (emptyfn_.IsEmpty(slot)) { |
| return NumBuckets(); |
| } |
| if (pred_(slot, element)) { |
| return index; |
| } |
| index = NextIndex(index); |
| } |
| } |
| |
| bool IsFreeSlot(size_t index) const { |
| return emptyfn_.IsEmpty(ElementForIndex(index)); |
| } |
| |
| // Allocate a number of buckets. |
| void AllocateStorage(size_t num_buckets) { |
| num_buckets_ = num_buckets; |
| data_ = allocfn_.allocate(num_buckets_); |
| owns_data_ = true; |
| for (size_t i = 0; i < num_buckets_; ++i) { |
| allocfn_.construct(allocfn_.address(data_[i])); |
| emptyfn_.MakeEmpty(data_[i]); |
| } |
| } |
| |
| void DeallocateStorage() { |
| if (owns_data_) { |
| for (size_t i = 0; i < NumBuckets(); ++i) { |
| allocfn_.destroy(allocfn_.address(data_[i])); |
| } |
| if (data_ != nullptr) { |
| allocfn_.deallocate(data_, NumBuckets()); |
| } |
| owns_data_ = false; |
| } |
| data_ = nullptr; |
| num_buckets_ = 0; |
| } |
| |
| // Expand the set based on the load factors. |
| void Expand() { |
| size_t min_index = static_cast<size_t>(Size() / min_load_factor_); |
| // Resize based on the minimum load factor. |
| Resize(min_index); |
| } |
| |
| // Expand / shrink the table to the new specified size. |
| void Resize(size_t new_size) { |
| if (new_size < kMinBuckets) { |
| new_size = kMinBuckets; |
| } |
| DCHECK_GE(new_size, Size()); |
| T* const old_data = data_; |
| size_t old_num_buckets = num_buckets_; |
| // Reinsert all of the old elements. |
| const bool owned_data = owns_data_; |
| AllocateStorage(new_size); |
| for (size_t i = 0; i < old_num_buckets; ++i) { |
| T& element = old_data[i]; |
| if (!emptyfn_.IsEmpty(element)) { |
| data_[FirstAvailableSlot(IndexForHash(hashfn_(element)))] = std::move(element); |
| } |
| if (owned_data) { |
| allocfn_.destroy(allocfn_.address(element)); |
| } |
| } |
| if (owned_data) { |
| allocfn_.deallocate(old_data, old_num_buckets); |
| } |
| |
| // When we hit elements_until_expand_, we are at the max load factor and must expand again. |
| elements_until_expand_ = NumBuckets() * max_load_factor_; |
| } |
| |
| ALWAYS_INLINE size_t FirstAvailableSlot(size_t index) const { |
| DCHECK_LT(index, NumBuckets()); // Don't try to get a slot out of range. |
| size_t non_empty_count = 0; |
| while (!emptyfn_.IsEmpty(data_[index])) { |
| index = NextIndex(index); |
| non_empty_count++; |
| DCHECK_LE(non_empty_count, NumBuckets()); // Don't loop forever. |
| } |
| return index; |
| } |
| |
| // Return new offset. |
| template <typename Elem> |
| static size_t WriteToBytes(uint8_t* ptr, size_t offset, Elem n) { |
| DCHECK_ALIGNED(ptr + offset, sizeof(n)); |
| if (ptr != nullptr) { |
| *reinterpret_cast<Elem*>(ptr + offset) = n; |
| } |
| return offset + sizeof(n); |
| } |
| |
| template <typename Elem> |
| static size_t ReadFromBytes(const uint8_t* ptr, size_t offset, Elem* out) { |
| DCHECK(ptr != nullptr); |
| DCHECK_ALIGNED(ptr + offset, sizeof(*out)); |
| *out = *reinterpret_cast<const Elem*>(ptr + offset); |
| return offset + sizeof(*out); |
| } |
| |
| Alloc allocfn_; // Allocator function. |
| HashFn hashfn_; // Hashing function. |
| EmptyFn emptyfn_; // IsEmpty/SetEmpty function. |
| Pred pred_; // Equals function. |
| size_t num_elements_; // Number of inserted elements. |
| size_t num_buckets_; // Number of hash table buckets. |
| size_t elements_until_expand_; // Maximum number of elements until we expand the table. |
| bool owns_data_; // If we own data_ and are responsible for freeing it. |
| T* data_; // Backing storage. |
| double min_load_factor_; |
| double max_load_factor_; |
| }; |
| |
| template <class T, class EmptyFn, class HashFn, class Pred, class Alloc> |
| void swap(HashSet<T, EmptyFn, HashFn, Pred, Alloc>& lhs, |
| HashSet<T, EmptyFn, HashFn, Pred, Alloc>& rhs) { |
| lhs.swap(rhs); |
| } |
| |
| } // namespace art |
| |
| #endif // ART_RUNTIME_BASE_HASH_SET_H_ |