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dawn-cmake/third_party/abseil-cpp/absl/container/internal/inlined_vector.h

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// 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 {
ABSL_NAMESPACE_BEGIN
namespace inlined_vector_internal {
// GCC does not deal very well with the below code
#if !defined(__clang__) && defined(__GNUC__)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Warray-bounds"
#pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
#endif
template <typename Iterator>
using IsAtLeastForwardIterator = std::is_convertible<
typename std::iterator_traits<Iterator>::iterator_category,
std::forward_iterator_tag>;
template <typename AllocatorType,
typename ValueType =
typename absl::allocator_traits<AllocatorType>::value_type>
using IsMemcpyOk =
absl::conjunction<std::is_same<AllocatorType, std::allocator<ValueType>>,
absl::is_trivially_copy_constructible<ValueType>,
absl::is_trivially_copy_assignable<ValueType>,
absl::is_trivially_destructible<ValueType>>;
template <typename AllocatorType, typename Pointer, typename SizeType>
void DestroyElements(AllocatorType* alloc_ptr, Pointer 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);
}
#if !defined(NDEBUG)
{
using ValueType = typename AllocatorTraits::value_type;
// 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.
void* memory_ptr = destroy_first;
auto memory_size = destroy_size * sizeof(ValueType);
std::memset(memory_ptr, 0xab, memory_size);
}
#endif // !defined(NDEBUG)
}
}
// If kUseMemcpy is true, memcpy(dst, src, n); else do nothing.
// Useful to avoid compiler warnings when memcpy() is used for T values
// that are not trivially copyable in non-reachable code.
template <bool kUseMemcpy>
inline void MemcpyIfAllowed(void* dst, const void* src, size_t n);
// memcpy when allowed.
template <>
inline void MemcpyIfAllowed<true>(void* dst, const void* src, size_t n) {
memcpy(dst, src, n);
}
// Do nothing for types that are not memcpy-able. This function is only
// called from non-reachable branches.
template <>
inline void MemcpyIfAllowed<false>(void*, const void*, size_t) {}
template <typename AllocatorType, typename Pointer, typename ValueAdapter,
typename SizeType>
void ConstructElements(AllocatorType* alloc_ptr, Pointer 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 Pointer, typename ValueAdapter, typename SizeType>
void AssignElements(Pointer 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 AllocatorTraits = absl::allocator_traits<AllocatorType>;
using Pointer = typename AllocatorTraits::pointer;
using SizeType = typename AllocatorTraits::size_type;
Pointer data;
SizeType size;
SizeType capacity;
};
template <typename AllocatorType, typename Iterator>
class IteratorValueAdapter {
using AllocatorTraits = absl::allocator_traits<AllocatorType>;
using Pointer = typename AllocatorTraits::pointer;
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 AllocatorTraits = absl::allocator_traits<AllocatorType>;
using ValueType = typename AllocatorTraits::value_type;
using Pointer = typename AllocatorTraits::pointer;
using ConstPointer = typename AllocatorTraits::const_pointer;
public:
explicit CopyValueAdapter(const ValueType& 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:
ConstPointer ptr_;
};
template <typename AllocatorType>
class DefaultValueAdapter {
using AllocatorTraits = absl::allocator_traits<AllocatorType>;
using ValueType = typename AllocatorTraits::value_type;
using Pointer = typename AllocatorTraits::pointer;
public:
explicit DefaultValueAdapter() {}
void ConstructNext(AllocatorType* alloc_ptr, Pointer construct_at) {
AllocatorTraits::construct(*alloc_ptr, construct_at);
}
void AssignNext(Pointer assign_at) { *assign_at = ValueType(); }
};
template <typename AllocatorType>
class AllocationTransaction {
using AllocatorTraits = absl::allocator_traits<AllocatorType>;
using Pointer = typename AllocatorTraits::pointer;
using SizeType = typename AllocatorTraits::size_type;
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>(); }
SizeType& GetCapacity() { return capacity_; }
bool DidAllocate() { return GetData() != nullptr; }
Pointer Allocate(SizeType capacity) {
GetData() = AllocatorTraits::allocate(GetAllocator(), capacity);
GetCapacity() = capacity;
return GetData();
}
void Reset() {
GetData() = nullptr;
GetCapacity() = 0;
}
private:
container_internal::CompressedTuple<AllocatorType, Pointer> alloc_data_;
SizeType capacity_ = 0;
};
template <typename AllocatorType>
class ConstructionTransaction {
using AllocatorTraits = absl::allocator_traits<AllocatorType>;
using Pointer = typename AllocatorTraits::pointer;
using SizeType = typename AllocatorTraits::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>(); }
SizeType& GetSize() { return size_; }
bool DidConstruct() { return GetData() != nullptr; }
template <typename ValueAdapter>
void Construct(Pointer data, ValueAdapter* values_ptr, SizeType 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_;
SizeType size_ = 0;
};
template <typename T, size_t N, typename A>
class Storage {
public:
using AllocatorTraits = absl::allocator_traits<A>;
using allocator_type = typename AllocatorTraits::allocator_type;
using value_type = typename AllocatorTraits::value_type;
using pointer = typename AllocatorTraits::pointer;
using const_pointer = typename AllocatorTraits::const_pointer;
using size_type = typename AllocatorTraits::size_type;
using difference_type = typename AllocatorTraits::difference_type;
using reference = value_type&;
using const_reference = const value_type&;
using RValueReference = value_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 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_(allocator_type(), /* size and is_allocated */ 0) {}
explicit Storage(const allocator_type& alloc)
: metadata_(alloc, /* size and is_allocated */ 0) {}
~Storage() {
if (GetSizeAndIsAllocated() == 0) {
// Empty and not allocated; nothing to do.
} else if (IsMemcpyOk::value) {
// No destructors need to be run; just deallocate if necessary.
DeallocateIfAllocated();
} else {
DestroyContents();
}
}
// ---------------------------------------------------------------------------
// 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
// ---------------------------------------------------------------------------
ABSL_ATTRIBUTE_NOINLINE void InitFrom(const Storage& other);
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->Reset();
}
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:
ABSL_ATTRIBUTE_NOINLINE void DestroyContents();
using Metadata =
container_internal::CompressedTuple<allocator_type, size_type>;
struct Allocated {
pointer allocated_data;
size_type allocated_capacity;
};
struct Inlined {
alignas(value_type) char inlined_data[sizeof(value_type[N])];
};
union Data {
Allocated allocated;
Inlined inlined;
};
template <typename... Args>
ABSL_ATTRIBUTE_NOINLINE reference EmplaceBackSlow(Args&&... args);
Metadata metadata_;
Data data_;
};
template <typename T, size_t N, typename A>
void Storage<T, N, A>::DestroyContents() {
pointer data = GetIsAllocated() ? GetAllocatedData() : GetInlinedData();
inlined_vector_internal::DestroyElements(GetAllocPtr(), data, GetSize());
DeallocateIfAllocated();
}
template <typename T, size_t N, typename A>
void Storage<T, N, A>::InitFrom(const Storage& other) {
const auto n = other.GetSize();
assert(n > 0); // Empty sources handled handled in caller.
const_pointer src;
pointer dst;
if (!other.GetIsAllocated()) {
dst = GetInlinedData();
src = other.GetInlinedData();
} else {
// 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(), n);
dst = AllocatorTraits::allocate(*GetAllocPtr(), new_capacity);
SetAllocatedData(dst, new_capacity);
src = other.GetAllocatedData();
}
if (IsMemcpyOk::value) {
MemcpyIfAllowed<IsMemcpyOk::value>(dst, src, sizeof(dst[0]) * n);
} else {
auto values = IteratorValueAdapter<const_pointer>(src);
inlined_vector_internal::ConstructElements(GetAllocPtr(), dst, &values, n);
}
GetSizeAndIsAllocated() = other.GetSizeAndIsAllocated();
}
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);
construct_data = AllocatorTraits::allocate(*GetAllocPtr(), new_capacity);
SetAllocatedData(construct_data, new_capacity);
SetIsAllocated();
} 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);
construct_loop = {allocation_tx.Allocate(new_capacity), 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();
auto* const base = storage_view.data;
const size_type size = storage_view.size;
auto* alloc = GetAllocPtr();
if (new_size <= size) {
// Destroy extra old elements.
inlined_vector_internal::DestroyElements(alloc, base + new_size,
size - new_size);
} else if (new_size <= storage_view.capacity) {
// Construct new elements in place.
inlined_vector_internal::ConstructElements(alloc, base + size, &values,
new_size - size);
} else {
// Steps:
// a. Allocate new backing store.
// b. Construct new elements in new backing store.
// c. Move existing elements from old backing store to now.
// d. Destroy all elements in old backing store.
// Use transactional wrappers for the first two steps so we can roll
// back if necessary due to exceptions.
AllocationTransaction allocation_tx(alloc);
size_type new_capacity = ComputeCapacity(storage_view.capacity, new_size);
pointer new_data = allocation_tx.Allocate(new_capacity);
ConstructionTransaction construction_tx(alloc);
construction_tx.Construct(new_data + size, &values, new_size - size);
IteratorValueAdapter<MoveIterator> move_values((MoveIterator(base)));
inlined_vector_internal::ConstructElements(alloc, new_data, &move_values,
size);
inlined_vector_internal::DestroyElements(alloc, base, size);
construction_tx.Commit();
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();
const auto n = storage_view.size;
if (ABSL_PREDICT_TRUE(n != storage_view.capacity)) {
// Fast path; new element fits.
pointer last_ptr = storage_view.data + n;
AllocatorTraits::construct(*GetAllocPtr(), last_ptr,
std::forward<Args>(args)...);
AddSize(1);
return *last_ptr;
}
// TODO(b/173712035): Annotate with musttail attribute to prevent regression.
return EmplaceBackSlow(std::forward<Args>(args)...);
}
template <typename T, size_t N, typename A>
template <typename... Args>
auto Storage<T, N, A>::EmplaceBackSlow(Args&&... args) -> reference {
StorageView storage_view = MakeStorageView();
AllocationTransaction allocation_tx(GetAllocPtr());
IteratorValueAdapter<MoveIterator> move_values(
MoveIterator(storage_view.data));
size_type new_capacity = NextCapacity(storage_view.capacity);
pointer construct_data = allocation_tx.Allocate(new_capacity);
pointer last_ptr = construct_data + storage_view.size;
// Construct new element.
AllocatorTraits::construct(*GetAllocPtr(), last_ptr,
std::forward<Args>(args)...);
// Move elements from old backing store to new backing store.
ABSL_INTERNAL_TRY {
inlined_vector_internal::ConstructElements(
GetAllocPtr(), allocation_tx.GetData(), &move_values,
storage_view.size);
}
ABSL_INTERNAL_CATCH_ANY {
AllocatorTraits::destroy(*GetAllocPtr(), last_ptr);
ABSL_INTERNAL_RETHROW;
}
// Destroy elements in old backing store.
inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data,
storage_view.size);
DeallocateIfAllocated();
AcquireAllocatedData(&allocation_tx);
SetIsAllocated();
AddSize(1);
return *last_ptr;
}
template <typename T, size_t N, typename A>
auto Storage<T, N, A>::Erase(const_iterator from, const_iterator to)
-> iterator {
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;
construct_data = allocation_tx.Allocate(new_capacity);
} 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());
}
// End ignore "array-bounds" and "maybe-uninitialized"
#if !defined(__clang__) && defined(__GNUC__)
#pragma GCC diagnostic pop
#endif
} // namespace inlined_vector_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_INLINED_VECTOR_INTERNAL_H_
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