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Diffstat (limited to 'absl/container/internal/inlined_vector.h')
| -rw-r--r-- | absl/container/internal/inlined_vector.h | 895 |
1 files changed, 895 insertions, 0 deletions
diff --git a/absl/container/internal/inlined_vector.h b/absl/container/internal/inlined_vector.h new file mode 100644 index 00000000..123e04c9 --- /dev/null +++ b/absl/container/internal/inlined_vector.h @@ -0,0 +1,895 @@ +// Copyright 2019 The Abseil Authors. +// +// 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 +// +// https://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 ABSL_CONTAINER_INTERNAL_INLINED_VECTOR_INTERNAL_H_ +#define ABSL_CONTAINER_INTERNAL_INLINED_VECTOR_INTERNAL_H_ + +#include <algorithm> +#include <cstddef> +#include <cstring> +#include <iterator> +#include <limits> +#include <memory> +#include <utility> + +#include "absl/base/macros.h" +#include "absl/container/internal/compressed_tuple.h" +#include "absl/memory/memory.h" +#include "absl/meta/type_traits.h" +#include "absl/types/span.h" + +namespace absl { +inline namespace lts_2019_08_08 { +namespace inlined_vector_internal { + +template <typename Iterator> +using IsAtLeastForwardIterator = std::is_convertible< + typename std::iterator_traits<Iterator>::iterator_category, + std::forward_iterator_tag>; + +template <typename AllocatorType> +using IsMemcpyOk = absl::conjunction< + std::is_same<std::allocator<typename AllocatorType::value_type>, + AllocatorType>, + absl::is_trivially_copy_constructible<typename AllocatorType::value_type>, + absl::is_trivially_copy_assignable<typename AllocatorType::value_type>, + absl::is_trivially_destructible<typename AllocatorType::value_type>>; + +template <typename AllocatorType, typename ValueType, typename SizeType> +void DestroyElements(AllocatorType* alloc_ptr, ValueType* destroy_first, + SizeType destroy_size) { + using AllocatorTraits = absl::allocator_traits<AllocatorType>; + + if (destroy_first != nullptr) { + for (auto i = destroy_size; i != 0;) { + --i; + AllocatorTraits::destroy(*alloc_ptr, destroy_first + i); + } + +#ifndef NDEBUG + // Overwrite unused memory with `0xab` so we can catch uninitialized usage. + // + // Cast to `void*` to tell the compiler that we don't care that we might be + // scribbling on a vtable pointer. + auto* memory_ptr = static_cast<void*>(destroy_first); + auto memory_size = sizeof(ValueType) * destroy_size; + std::memset(memory_ptr, 0xab, memory_size); +#endif // NDEBUG + } +} + +template <typename AllocatorType, typename ValueType, typename ValueAdapter, + typename SizeType> +void ConstructElements(AllocatorType* alloc_ptr, ValueType* construct_first, + ValueAdapter* values_ptr, SizeType construct_size) { + for (SizeType i = 0; i < construct_size; ++i) { + ABSL_INTERNAL_TRY { + values_ptr->ConstructNext(alloc_ptr, construct_first + i); + } + ABSL_INTERNAL_CATCH_ANY { + inlined_vector_internal::DestroyElements(alloc_ptr, construct_first, i); + ABSL_INTERNAL_RETHROW; + } + } +} + +template <typename ValueType, typename ValueAdapter, typename SizeType> +void AssignElements(ValueType* assign_first, ValueAdapter* values_ptr, + SizeType assign_size) { + for (SizeType i = 0; i < assign_size; ++i) { + values_ptr->AssignNext(assign_first + i); + } +} + +template <typename AllocatorType> +struct StorageView { + using pointer = typename AllocatorType::pointer; + using size_type = typename AllocatorType::size_type; + + pointer data; + size_type size; + size_type capacity; +}; + +template <typename AllocatorType, typename Iterator> +class IteratorValueAdapter { + using pointer = typename AllocatorType::pointer; + using AllocatorTraits = absl::allocator_traits<AllocatorType>; + + public: + explicit IteratorValueAdapter(const Iterator& it) : it_(it) {} + + void ConstructNext(AllocatorType* alloc_ptr, pointer construct_at) { + AllocatorTraits::construct(*alloc_ptr, construct_at, *it_); + ++it_; + } + + void AssignNext(pointer assign_at) { + *assign_at = *it_; + ++it_; + } + + private: + Iterator it_; +}; + +template <typename AllocatorType> +class CopyValueAdapter { + using pointer = typename AllocatorType::pointer; + using const_pointer = typename AllocatorType::const_pointer; + using const_reference = typename AllocatorType::const_reference; + using AllocatorTraits = absl::allocator_traits<AllocatorType>; + + public: + explicit CopyValueAdapter(const_reference v) : ptr_(std::addressof(v)) {} + + void ConstructNext(AllocatorType* alloc_ptr, pointer construct_at) { + AllocatorTraits::construct(*alloc_ptr, construct_at, *ptr_); + } + + void AssignNext(pointer assign_at) { *assign_at = *ptr_; } + + private: + const_pointer ptr_; +}; + +template <typename AllocatorType> +class DefaultValueAdapter { + using pointer = typename AllocatorType::pointer; + using value_type = typename AllocatorType::value_type; + using AllocatorTraits = absl::allocator_traits<AllocatorType>; + + public: + explicit DefaultValueAdapter() {} + + void ConstructNext(AllocatorType* alloc_ptr, pointer construct_at) { + AllocatorTraits::construct(*alloc_ptr, construct_at); + } + + void AssignNext(pointer assign_at) { *assign_at = value_type(); } +}; + +template <typename AllocatorType> +class AllocationTransaction { + using value_type = typename AllocatorType::value_type; + using pointer = typename AllocatorType::pointer; + using size_type = typename AllocatorType::size_type; + using AllocatorTraits = absl::allocator_traits<AllocatorType>; + + public: + explicit AllocationTransaction(AllocatorType* alloc_ptr) + : alloc_data_(*alloc_ptr, nullptr) {} + + ~AllocationTransaction() { + if (DidAllocate()) { + AllocatorTraits::deallocate(GetAllocator(), GetData(), GetCapacity()); + } + } + + AllocationTransaction(const AllocationTransaction&) = delete; + void operator=(const AllocationTransaction&) = delete; + + AllocatorType& GetAllocator() { return alloc_data_.template get<0>(); } + pointer& GetData() { return alloc_data_.template get<1>(); } + size_type& GetCapacity() { return capacity_; } + + bool DidAllocate() { return GetData() != nullptr; } + pointer Allocate(size_type capacity) { + GetData() = AllocatorTraits::allocate(GetAllocator(), capacity); + GetCapacity() = capacity; + return GetData(); + } + + private: + container_internal::CompressedTuple<AllocatorType, pointer> alloc_data_; + size_type capacity_ = 0; +}; + +template <typename AllocatorType> +class ConstructionTransaction { + using pointer = typename AllocatorType::pointer; + using size_type = typename AllocatorType::size_type; + + public: + explicit ConstructionTransaction(AllocatorType* alloc_ptr) + : alloc_data_(*alloc_ptr, nullptr) {} + + ~ConstructionTransaction() { + if (DidConstruct()) { + inlined_vector_internal::DestroyElements(std::addressof(GetAllocator()), + GetData(), GetSize()); + } + } + + ConstructionTransaction(const ConstructionTransaction&) = delete; + void operator=(const ConstructionTransaction&) = delete; + + AllocatorType& GetAllocator() { return alloc_data_.template get<0>(); } + pointer& GetData() { return alloc_data_.template get<1>(); } + size_type& GetSize() { return size_; } + + bool DidConstruct() { return GetData() != nullptr; } + template <typename ValueAdapter> + void Construct(pointer data, ValueAdapter* values_ptr, size_type size) { + inlined_vector_internal::ConstructElements(std::addressof(GetAllocator()), + data, values_ptr, size); + GetData() = data; + GetSize() = size; + } + void Commit() { + GetData() = nullptr; + GetSize() = 0; + } + + private: + container_internal::CompressedTuple<AllocatorType, pointer> alloc_data_; + size_type size_ = 0; +}; + +template <typename T, size_t N, typename A> +class Storage { + public: + using allocator_type = A; + using value_type = typename allocator_type::value_type; + using pointer = typename allocator_type::pointer; + using const_pointer = typename allocator_type::const_pointer; + using reference = typename allocator_type::reference; + using const_reference = typename allocator_type::const_reference; + using rvalue_reference = typename allocator_type::value_type&&; + using size_type = typename allocator_type::size_type; + using difference_type = typename allocator_type::difference_type; + using iterator = pointer; + using const_iterator = const_pointer; + using reverse_iterator = std::reverse_iterator<iterator>; + using const_reverse_iterator = std::reverse_iterator<const_iterator>; + using MoveIterator = std::move_iterator<iterator>; + using AllocatorTraits = absl::allocator_traits<allocator_type>; + using IsMemcpyOk = inlined_vector_internal::IsMemcpyOk<allocator_type>; + + using StorageView = inlined_vector_internal::StorageView<allocator_type>; + + template <typename Iterator> + using IteratorValueAdapter = + inlined_vector_internal::IteratorValueAdapter<allocator_type, Iterator>; + using CopyValueAdapter = + inlined_vector_internal::CopyValueAdapter<allocator_type>; + using DefaultValueAdapter = + inlined_vector_internal::DefaultValueAdapter<allocator_type>; + + using AllocationTransaction = + inlined_vector_internal::AllocationTransaction<allocator_type>; + using ConstructionTransaction = + inlined_vector_internal::ConstructionTransaction<allocator_type>; + + static size_type NextCapacity(size_type current_capacity) { + return current_capacity * 2; + } + + static size_type ComputeCapacity(size_type current_capacity, + size_type requested_capacity) { + return (std::max)(NextCapacity(current_capacity), requested_capacity); + } + + // --------------------------------------------------------------------------- + // Storage Constructors and Destructor + // --------------------------------------------------------------------------- + + Storage() : metadata_() {} + + explicit Storage(const allocator_type& alloc) + : metadata_(alloc, /* empty and inlined */ 0) {} + + ~Storage() { + pointer data = GetIsAllocated() ? GetAllocatedData() : GetInlinedData(); + inlined_vector_internal::DestroyElements(GetAllocPtr(), data, GetSize()); + DeallocateIfAllocated(); + } + + // --------------------------------------------------------------------------- + // Storage Member Accessors + // --------------------------------------------------------------------------- + + size_type& GetSizeAndIsAllocated() { return metadata_.template get<1>(); } + + const size_type& GetSizeAndIsAllocated() const { + return metadata_.template get<1>(); + } + + size_type GetSize() const { return GetSizeAndIsAllocated() >> 1; } + + bool GetIsAllocated() const { return GetSizeAndIsAllocated() & 1; } + + pointer GetAllocatedData() { return data_.allocated.allocated_data; } + + const_pointer GetAllocatedData() const { + return data_.allocated.allocated_data; + } + + pointer GetInlinedData() { + return reinterpret_cast<pointer>( + std::addressof(data_.inlined.inlined_data[0])); + } + + const_pointer GetInlinedData() const { + return reinterpret_cast<const_pointer>( + std::addressof(data_.inlined.inlined_data[0])); + } + + size_type GetAllocatedCapacity() const { + return data_.allocated.allocated_capacity; + } + + size_type GetInlinedCapacity() const { return static_cast<size_type>(N); } + + StorageView MakeStorageView() { + return GetIsAllocated() + ? StorageView{GetAllocatedData(), GetSize(), + GetAllocatedCapacity()} + : StorageView{GetInlinedData(), GetSize(), GetInlinedCapacity()}; + } + + allocator_type* GetAllocPtr() { + return std::addressof(metadata_.template get<0>()); + } + + const allocator_type* GetAllocPtr() const { + return std::addressof(metadata_.template get<0>()); + } + + // --------------------------------------------------------------------------- + // Storage Member Mutators + // --------------------------------------------------------------------------- + + template <typename ValueAdapter> + void Initialize(ValueAdapter values, size_type new_size); + + template <typename ValueAdapter> + void Assign(ValueAdapter values, size_type new_size); + + template <typename ValueAdapter> + void Resize(ValueAdapter values, size_type new_size); + + template <typename ValueAdapter> + iterator Insert(const_iterator pos, ValueAdapter values, + size_type insert_count); + + template <typename... Args> + reference EmplaceBack(Args&&... args); + + iterator Erase(const_iterator from, const_iterator to); + + void Reserve(size_type requested_capacity); + + void ShrinkToFit(); + + void Swap(Storage* other_storage_ptr); + + void SetIsAllocated() { + GetSizeAndIsAllocated() |= static_cast<size_type>(1); + } + + void UnsetIsAllocated() { + GetSizeAndIsAllocated() &= ((std::numeric_limits<size_type>::max)() - 1); + } + + void SetSize(size_type size) { + GetSizeAndIsAllocated() = + (size << 1) | static_cast<size_type>(GetIsAllocated()); + } + + void SetAllocatedSize(size_type size) { + GetSizeAndIsAllocated() = (size << 1) | static_cast<size_type>(1); + } + + void SetInlinedSize(size_type size) { + GetSizeAndIsAllocated() = size << static_cast<size_type>(1); + } + + void AddSize(size_type count) { + GetSizeAndIsAllocated() += count << static_cast<size_type>(1); + } + + void SubtractSize(size_type count) { + assert(count <= GetSize()); + + GetSizeAndIsAllocated() -= count << static_cast<size_type>(1); + } + + void SetAllocatedData(pointer data, size_type capacity) { + data_.allocated.allocated_data = data; + data_.allocated.allocated_capacity = capacity; + } + + void AcquireAllocatedData(AllocationTransaction* allocation_tx_ptr) { + SetAllocatedData(allocation_tx_ptr->GetData(), + allocation_tx_ptr->GetCapacity()); + allocation_tx_ptr->GetData() = nullptr; + allocation_tx_ptr->GetCapacity() = 0; + } + + void MemcpyFrom(const Storage& other_storage) { + assert(IsMemcpyOk::value || other_storage.GetIsAllocated()); + + GetSizeAndIsAllocated() = other_storage.GetSizeAndIsAllocated(); + data_ = other_storage.data_; + } + + void DeallocateIfAllocated() { + if (GetIsAllocated()) { + AllocatorTraits::deallocate(*GetAllocPtr(), GetAllocatedData(), + GetAllocatedCapacity()); + } + } + + private: + using Metadata = + container_internal::CompressedTuple<allocator_type, size_type>; + + struct Allocated { + pointer allocated_data; + size_type allocated_capacity; + }; + + struct Inlined { + using InlinedDataElement = + absl::aligned_storage_t<sizeof(value_type), alignof(value_type)>; + InlinedDataElement inlined_data[N]; + }; + + union Data { + Allocated allocated; + Inlined inlined; + }; + + Metadata metadata_; + Data data_; +}; + +template <typename T, size_t N, typename A> +template <typename ValueAdapter> +auto Storage<T, N, A>::Initialize(ValueAdapter values, size_type new_size) + -> void { + // Only callable from constructors! + assert(!GetIsAllocated()); + assert(GetSize() == 0); + + pointer construct_data; + + if (new_size > GetInlinedCapacity()) { + // Because this is only called from the `InlinedVector` constructors, it's + // safe to take on the allocation with size `0`. If `ConstructElements(...)` + // throws, deallocation will be automatically handled by `~Storage()`. + size_type new_capacity = ComputeCapacity(GetInlinedCapacity(), new_size); + pointer new_data = AllocatorTraits::allocate(*GetAllocPtr(), new_capacity); + + SetAllocatedData(new_data, new_capacity); + SetIsAllocated(); + + construct_data = new_data; + } else { + construct_data = GetInlinedData(); + } + + inlined_vector_internal::ConstructElements(GetAllocPtr(), construct_data, + &values, new_size); + + // Since the initial size was guaranteed to be `0` and the allocated bit is + // already correct for either case, *adding* `new_size` gives us the correct + // result faster than setting it directly. + AddSize(new_size); +} + +template <typename T, size_t N, typename A> +template <typename ValueAdapter> +auto Storage<T, N, A>::Assign(ValueAdapter values, size_type new_size) -> void { + StorageView storage_view = MakeStorageView(); + + AllocationTransaction allocation_tx(GetAllocPtr()); + + absl::Span<value_type> assign_loop; + absl::Span<value_type> construct_loop; + absl::Span<value_type> destroy_loop; + + if (new_size > storage_view.capacity) { + size_type new_capacity = ComputeCapacity(storage_view.capacity, new_size); + pointer new_data = allocation_tx.Allocate(new_capacity); + + construct_loop = {new_data, new_size}; + destroy_loop = {storage_view.data, storage_view.size}; + } else if (new_size > storage_view.size) { + assign_loop = {storage_view.data, storage_view.size}; + construct_loop = {storage_view.data + storage_view.size, + new_size - storage_view.size}; + } else { + assign_loop = {storage_view.data, new_size}; + destroy_loop = {storage_view.data + new_size, storage_view.size - new_size}; + } + + inlined_vector_internal::AssignElements(assign_loop.data(), &values, + assign_loop.size()); + + inlined_vector_internal::ConstructElements( + GetAllocPtr(), construct_loop.data(), &values, construct_loop.size()); + + inlined_vector_internal::DestroyElements(GetAllocPtr(), destroy_loop.data(), + destroy_loop.size()); + + if (allocation_tx.DidAllocate()) { + DeallocateIfAllocated(); + AcquireAllocatedData(&allocation_tx); + SetIsAllocated(); + } + + SetSize(new_size); +} + +template <typename T, size_t N, typename A> +template <typename ValueAdapter> +auto Storage<T, N, A>::Resize(ValueAdapter values, size_type new_size) -> void { + StorageView storage_view = MakeStorageView(); + + AllocationTransaction allocation_tx(GetAllocPtr()); + ConstructionTransaction construction_tx(GetAllocPtr()); + + IteratorValueAdapter<MoveIterator> move_values( + MoveIterator(storage_view.data)); + + absl::Span<value_type> construct_loop; + absl::Span<value_type> move_construct_loop; + absl::Span<value_type> destroy_loop; + + if (new_size > storage_view.capacity) { + size_type new_capacity = ComputeCapacity(storage_view.capacity, new_size); + pointer new_data = allocation_tx.Allocate(new_capacity); + construct_loop = {new_data + storage_view.size, + new_size - storage_view.size}; + move_construct_loop = {new_data, storage_view.size}; + destroy_loop = {storage_view.data, storage_view.size}; + } else if (new_size > storage_view.size) { + construct_loop = {storage_view.data + storage_view.size, + new_size - storage_view.size}; + } else { + destroy_loop = {storage_view.data + new_size, storage_view.size - new_size}; + } + + construction_tx.Construct(construct_loop.data(), &values, + construct_loop.size()); + + inlined_vector_internal::ConstructElements( + GetAllocPtr(), move_construct_loop.data(), &move_values, + move_construct_loop.size()); + + inlined_vector_internal::DestroyElements(GetAllocPtr(), destroy_loop.data(), + destroy_loop.size()); + + construction_tx.Commit(); + if (allocation_tx.DidAllocate()) { + DeallocateIfAllocated(); + AcquireAllocatedData(&allocation_tx); + SetIsAllocated(); + } + + SetSize(new_size); +} + +template <typename T, size_t N, typename A> +template <typename ValueAdapter> +auto Storage<T, N, A>::Insert(const_iterator pos, ValueAdapter values, + size_type insert_count) -> iterator { + StorageView storage_view = MakeStorageView(); + + size_type insert_index = + std::distance(const_iterator(storage_view.data), pos); + size_type insert_end_index = insert_index + insert_count; + size_type new_size = storage_view.size + insert_count; + + if (new_size > storage_view.capacity) { + AllocationTransaction allocation_tx(GetAllocPtr()); + ConstructionTransaction construction_tx(GetAllocPtr()); + ConstructionTransaction move_construciton_tx(GetAllocPtr()); + + IteratorValueAdapter<MoveIterator> move_values( + MoveIterator(storage_view.data)); + + size_type new_capacity = ComputeCapacity(storage_view.capacity, new_size); + pointer new_data = allocation_tx.Allocate(new_capacity); + + construction_tx.Construct(new_data + insert_index, &values, insert_count); + + move_construciton_tx.Construct(new_data, &move_values, insert_index); + + inlined_vector_internal::ConstructElements( + GetAllocPtr(), new_data + insert_end_index, &move_values, + storage_view.size - insert_index); + + inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data, + storage_view.size); + + construction_tx.Commit(); + move_construciton_tx.Commit(); + DeallocateIfAllocated(); + AcquireAllocatedData(&allocation_tx); + + SetAllocatedSize(new_size); + return iterator(new_data + insert_index); + } else { + size_type move_construction_destination_index = + (std::max)(insert_end_index, storage_view.size); + + ConstructionTransaction move_construction_tx(GetAllocPtr()); + + IteratorValueAdapter<MoveIterator> move_construction_values( + MoveIterator(storage_view.data + + (move_construction_destination_index - insert_count))); + absl::Span<value_type> move_construction = { + storage_view.data + move_construction_destination_index, + new_size - move_construction_destination_index}; + + pointer move_assignment_values = storage_view.data + insert_index; + absl::Span<value_type> move_assignment = { + storage_view.data + insert_end_index, + move_construction_destination_index - insert_end_index}; + + absl::Span<value_type> insert_assignment = {move_assignment_values, + move_construction.size()}; + + absl::Span<value_type> insert_construction = { + insert_assignment.data() + insert_assignment.size(), + insert_count - insert_assignment.size()}; + + move_construction_tx.Construct(move_construction.data(), + &move_construction_values, + move_construction.size()); + + for (pointer destination = move_assignment.data() + move_assignment.size(), + last_destination = move_assignment.data(), + source = move_assignment_values + move_assignment.size(); + ;) { + --destination; + --source; + if (destination < last_destination) break; + *destination = std::move(*source); + } + + inlined_vector_internal::AssignElements(insert_assignment.data(), &values, + insert_assignment.size()); + + inlined_vector_internal::ConstructElements( + GetAllocPtr(), insert_construction.data(), &values, + insert_construction.size()); + + move_construction_tx.Commit(); + + AddSize(insert_count); + return iterator(storage_view.data + insert_index); + } +} + +template <typename T, size_t N, typename A> +template <typename... Args> +auto Storage<T, N, A>::EmplaceBack(Args&&... args) -> reference { + StorageView storage_view = MakeStorageView(); + + AllocationTransaction allocation_tx(GetAllocPtr()); + + IteratorValueAdapter<MoveIterator> move_values( + MoveIterator(storage_view.data)); + + pointer construct_data; + + if (storage_view.size == storage_view.capacity) { + size_type new_capacity = NextCapacity(storage_view.capacity); + pointer new_data = allocation_tx.Allocate(new_capacity); + + construct_data = new_data; + } else { + construct_data = storage_view.data; + } + + pointer end = construct_data + storage_view.size; + + AllocatorTraits::construct(*GetAllocPtr(), end, std::forward<Args>(args)...); + + if (allocation_tx.DidAllocate()) { + ABSL_INTERNAL_TRY { + inlined_vector_internal::ConstructElements( + GetAllocPtr(), allocation_tx.GetData(), &move_values, + storage_view.size); + } + ABSL_INTERNAL_CATCH_ANY { + AllocatorTraits::destroy(*GetAllocPtr(), end); + ABSL_INTERNAL_RETHROW; + } + + inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data, + storage_view.size); + + DeallocateIfAllocated(); + AcquireAllocatedData(&allocation_tx); + SetIsAllocated(); + } + + AddSize(1); + return *end; +} + +template <typename T, size_t N, typename A> +auto Storage<T, N, A>::Erase(const_iterator from, const_iterator to) + -> iterator { + assert(from != to); + + StorageView storage_view = MakeStorageView(); + + size_type erase_size = std::distance(from, to); + size_type erase_index = + std::distance(const_iterator(storage_view.data), from); + size_type erase_end_index = erase_index + erase_size; + + IteratorValueAdapter<MoveIterator> move_values( + MoveIterator(storage_view.data + erase_end_index)); + + inlined_vector_internal::AssignElements(storage_view.data + erase_index, + &move_values, + storage_view.size - erase_end_index); + + inlined_vector_internal::DestroyElements( + GetAllocPtr(), storage_view.data + (storage_view.size - erase_size), + erase_size); + + SubtractSize(erase_size); + return iterator(storage_view.data + erase_index); +} + +template <typename T, size_t N, typename A> +auto Storage<T, N, A>::Reserve(size_type requested_capacity) -> void { + StorageView storage_view = MakeStorageView(); + + if (ABSL_PREDICT_FALSE(requested_capacity <= storage_view.capacity)) return; + + AllocationTransaction allocation_tx(GetAllocPtr()); + + IteratorValueAdapter<MoveIterator> move_values( + MoveIterator(storage_view.data)); + + size_type new_capacity = + ComputeCapacity(storage_view.capacity, requested_capacity); + pointer new_data = allocation_tx.Allocate(new_capacity); + + inlined_vector_internal::ConstructElements(GetAllocPtr(), new_data, + &move_values, storage_view.size); + + inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data, + storage_view.size); + + DeallocateIfAllocated(); + AcquireAllocatedData(&allocation_tx); + SetIsAllocated(); +} + +template <typename T, size_t N, typename A> +auto Storage<T, N, A>::ShrinkToFit() -> void { + // May only be called on allocated instances! + assert(GetIsAllocated()); + + StorageView storage_view{GetAllocatedData(), GetSize(), + GetAllocatedCapacity()}; + + if (ABSL_PREDICT_FALSE(storage_view.size == storage_view.capacity)) return; + + AllocationTransaction allocation_tx(GetAllocPtr()); + + IteratorValueAdapter<MoveIterator> move_values( + MoveIterator(storage_view.data)); + + pointer construct_data; + + if (storage_view.size > GetInlinedCapacity()) { + size_type new_capacity = storage_view.size; + pointer new_data = allocation_tx.Allocate(new_capacity); + + construct_data = new_data; + } else { + construct_data = GetInlinedData(); + } + + ABSL_INTERNAL_TRY { + inlined_vector_internal::ConstructElements(GetAllocPtr(), construct_data, + &move_values, storage_view.size); + } + ABSL_INTERNAL_CATCH_ANY { + SetAllocatedData(storage_view.data, storage_view.capacity); + ABSL_INTERNAL_RETHROW; + } + + inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data, + storage_view.size); + + AllocatorTraits::deallocate(*GetAllocPtr(), storage_view.data, + storage_view.capacity); + + if (allocation_tx.DidAllocate()) { + AcquireAllocatedData(&allocation_tx); + } else { + UnsetIsAllocated(); + } +} + +template <typename T, size_t N, typename A> +auto Storage<T, N, A>::Swap(Storage* other_storage_ptr) -> void { + using std::swap; + assert(this != other_storage_ptr); + + if (GetIsAllocated() && other_storage_ptr->GetIsAllocated()) { + swap(data_.allocated, other_storage_ptr->data_.allocated); + } else if (!GetIsAllocated() && !other_storage_ptr->GetIsAllocated()) { + Storage* small_ptr = this; + Storage* large_ptr = other_storage_ptr; + if (small_ptr->GetSize() > large_ptr->GetSize()) swap(small_ptr, large_ptr); + + for (size_type i = 0; i < small_ptr->GetSize(); ++i) { + swap(small_ptr->GetInlinedData()[i], large_ptr->GetInlinedData()[i]); + } + + IteratorValueAdapter<MoveIterator> move_values( + MoveIterator(large_ptr->GetInlinedData() + small_ptr->GetSize())); + + inlined_vector_internal::ConstructElements( + large_ptr->GetAllocPtr(), + small_ptr->GetInlinedData() + small_ptr->GetSize(), &move_values, + large_ptr->GetSize() - small_ptr->GetSize()); + + inlined_vector_internal::DestroyElements( + large_ptr->GetAllocPtr(), + large_ptr->GetInlinedData() + small_ptr->GetSize(), + large_ptr->GetSize() - small_ptr->GetSize()); + } else { + Storage* allocated_ptr = this; + Storage* inlined_ptr = other_storage_ptr; + if (!allocated_ptr->GetIsAllocated()) swap(allocated_ptr, inlined_ptr); + + StorageView allocated_storage_view{allocated_ptr->GetAllocatedData(), + allocated_ptr->GetSize(), + allocated_ptr->GetAllocatedCapacity()}; + + IteratorValueAdapter<MoveIterator> move_values( + MoveIterator(inlined_ptr->GetInlinedData())); + + ABSL_INTERNAL_TRY { + inlined_vector_internal::ConstructElements( + inlined_ptr->GetAllocPtr(), allocated_ptr->GetInlinedData(), + &move_values, inlined_ptr->GetSize()); + } + ABSL_INTERNAL_CATCH_ANY { + allocated_ptr->SetAllocatedData(allocated_storage_view.data, + allocated_storage_view.capacity); + ABSL_INTERNAL_RETHROW; + } + + inlined_vector_internal::DestroyElements(inlined_ptr->GetAllocPtr(), + inlined_ptr->GetInlinedData(), + inlined_ptr->GetSize()); + + inlined_ptr->SetAllocatedData(allocated_storage_view.data, + allocated_storage_view.capacity); + } + + swap(GetSizeAndIsAllocated(), other_storage_ptr->GetSizeAndIsAllocated()); + swap(*GetAllocPtr(), *other_storage_ptr->GetAllocPtr()); +} + +} // namespace inlined_vector_internal +} // inline namespace lts_2019_08_08 +} // namespace absl + +#endif // ABSL_CONTAINER_INTERNAL_INLINED_VECTOR_INTERNAL_H_ |