Add 'third_party/abseil_cpp/' from commit '768eb2ca2857342673fcd462792ce04b8bac3fa3' r/781

git-subtree-dir: third_party/abseil_cpp
git-subtree-mainline: ffb2ae54beb5796cd408fbe15d2d2da09ff37adf
git-subtree-split: 768eb2ca2857342673fcd462792ce04b8bac3fa3

1 files changed, 845 insertions, 0 deletions

diff --git a/third_party/abseil_cpp/absl/container/inlined_vector.h b/third_party/abseil_cpp/absl/container/inlined_vector.h
new file mode 100644
index 000000000000..f18dd4c78583
--- /dev/null
+++ b/third_party/abseil_cpp/absl/container/inlined_vector.h
@@ -0,0 +1,845 @@
+// 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.
+//
+// -----------------------------------------------------------------------------
+// File: inlined_vector.h
+// -----------------------------------------------------------------------------
+//
+// This header file contains the declaration and definition of an "inlined
+// vector" which behaves in an equivalent fashion to a `std::vector`, except
+// that storage for small sequences of the vector are provided inline without
+// requiring any heap allocation.
+//
+// An `absl::InlinedVector<T, N>` specifies the default capacity `N` as one of
+// its template parameters. Instances where `size() <= N` hold contained
+// elements in inline space. Typically `N` is very small so that sequences that
+// are expected to be short do not require allocations.
+//
+// An `absl::InlinedVector` does not usually require a specific allocator. If
+// the inlined vector grows beyond its initial constraints, it will need to
+// allocate (as any normal `std::vector` would). This is usually performed with
+// the default allocator (defined as `std::allocator<T>`). Optionally, a custom
+// allocator type may be specified as `A` in `absl::InlinedVector<T, N, A>`.
+
+#ifndef ABSL_CONTAINER_INLINED_VECTOR_H_
+#define ABSL_CONTAINER_INLINED_VECTOR_H_
+
+#include <algorithm>
+#include <cassert>
+#include <cstddef>
+#include <cstdlib>
+#include <cstring>
+#include <initializer_list>
+#include <iterator>
+#include <memory>
+#include <type_traits>
+#include <utility>
+
+#include "absl/algorithm/algorithm.h"
+#include "absl/base/internal/throw_delegate.h"
+#include "absl/base/macros.h"
+#include "absl/base/optimization.h"
+#include "absl/base/port.h"
+#include "absl/container/internal/inlined_vector.h"
+#include "absl/memory/memory.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+// -----------------------------------------------------------------------------
+// InlinedVector
+// -----------------------------------------------------------------------------
+//
+// An `absl::InlinedVector` is designed to be a drop-in replacement for
+// `std::vector` for use cases where the vector's size is sufficiently small
+// that it can be inlined. If the inlined vector does grow beyond its estimated
+// capacity, it will trigger an initial allocation on the heap, and will behave
+// as a `std:vector`. The API of the `absl::InlinedVector` within this file is
+// designed to cover the same API footprint as covered by `std::vector`.
+template <typename T, size_t N, typename A = std::allocator<T>>
+class InlinedVector {
+  static_assert(N > 0, "`absl::InlinedVector` requires an inlined capacity.");
+
+  using Storage = inlined_vector_internal::Storage<T, N, A>;
+
+  using AllocatorTraits = typename Storage::AllocatorTraits;
+  using RValueReference = typename Storage::RValueReference;
+  using MoveIterator = typename Storage::MoveIterator;
+  using IsMemcpyOk = typename Storage::IsMemcpyOk;
+
+  template <typename Iterator>
+  using IteratorValueAdapter =
+      typename Storage::template IteratorValueAdapter<Iterator>;
+  using CopyValueAdapter = typename Storage::CopyValueAdapter;
+  using DefaultValueAdapter = typename Storage::DefaultValueAdapter;
+
+  template <typename Iterator>
+  using EnableIfAtLeastForwardIterator = absl::enable_if_t<
+      inlined_vector_internal::IsAtLeastForwardIterator<Iterator>::value>;
+  template <typename Iterator>
+  using DisableIfAtLeastForwardIterator = absl::enable_if_t<
+      !inlined_vector_internal::IsAtLeastForwardIterator<Iterator>::value>;
+
+ public:
+  using allocator_type = typename Storage::allocator_type;
+  using value_type = typename Storage::value_type;
+  using pointer = typename Storage::pointer;
+  using const_pointer = typename Storage::const_pointer;
+  using size_type = typename Storage::size_type;
+  using difference_type = typename Storage::difference_type;
+  using reference = typename Storage::reference;
+  using const_reference = typename Storage::const_reference;
+  using iterator = typename Storage::iterator;
+  using const_iterator = typename Storage::const_iterator;
+  using reverse_iterator = typename Storage::reverse_iterator;
+  using const_reverse_iterator = typename Storage::const_reverse_iterator;
+
+  // ---------------------------------------------------------------------------
+  // InlinedVector Constructors and Destructor
+  // ---------------------------------------------------------------------------
+
+  // Creates an empty inlined vector with a value-initialized allocator.
+  InlinedVector() noexcept(noexcept(allocator_type())) : storage_() {}
+
+  // Creates an empty inlined vector with a copy of `alloc`.
+  explicit InlinedVector(const allocator_type& alloc) noexcept
+      : storage_(alloc) {}
+
+  // Creates an inlined vector with `n` copies of `value_type()`.
+  explicit InlinedVector(size_type n,
+                         const allocator_type& alloc = allocator_type())
+      : storage_(alloc) {
+    storage_.Initialize(DefaultValueAdapter(), n);
+  }
+
+  // Creates an inlined vector with `n` copies of `v`.
+  InlinedVector(size_type n, const_reference v,
+                const allocator_type& alloc = allocator_type())
+      : storage_(alloc) {
+    storage_.Initialize(CopyValueAdapter(v), n);
+  }
+
+  // Creates an inlined vector with copies of the elements of `list`.
+  InlinedVector(std::initializer_list<value_type> list,
+                const allocator_type& alloc = allocator_type())
+      : InlinedVector(list.begin(), list.end(), alloc) {}
+
+  // Creates an inlined vector with elements constructed from the provided
+  // forward iterator range [`first`, `last`).
+  //
+  // NOTE: the `enable_if` prevents ambiguous interpretation between a call to
+  // this constructor with two integral arguments and a call to the above
+  // `InlinedVector(size_type, const_reference)` constructor.
+  template <typename ForwardIterator,
+            EnableIfAtLeastForwardIterator<ForwardIterator>* = nullptr>
+  InlinedVector(ForwardIterator first, ForwardIterator last,
+                const allocator_type& alloc = allocator_type())
+      : storage_(alloc) {
+    storage_.Initialize(IteratorValueAdapter<ForwardIterator>(first),
+                        std::distance(first, last));
+  }
+
+  // Creates an inlined vector with elements constructed from the provided input
+  // iterator range [`first`, `last`).
+  template <typename InputIterator,
+            DisableIfAtLeastForwardIterator<InputIterator>* = nullptr>
+  InlinedVector(InputIterator first, InputIterator last,
+                const allocator_type& alloc = allocator_type())
+      : storage_(alloc) {
+    std::copy(first, last, std::back_inserter(*this));
+  }
+
+  // Creates an inlined vector by copying the contents of `other` using
+  // `other`'s allocator.
+  InlinedVector(const InlinedVector& other)
+      : InlinedVector(other, *other.storage_.GetAllocPtr()) {}
+
+  // Creates an inlined vector by copying the contents of `other` using `alloc`.
+  InlinedVector(const InlinedVector& other, const allocator_type& alloc)
+      : storage_(alloc) {
+    if (IsMemcpyOk::value && !other.storage_.GetIsAllocated()) {
+      storage_.MemcpyFrom(other.storage_);
+    } else {
+      storage_.Initialize(IteratorValueAdapter<const_pointer>(other.data()),
+                          other.size());
+    }
+  }
+
+  // Creates an inlined vector by moving in the contents of `other` without
+  // allocating. If `other` contains allocated memory, the newly-created inlined
+  // vector will take ownership of that memory. However, if `other` does not
+  // contain allocated memory, the newly-created inlined vector will perform
+  // element-wise move construction of the contents of `other`.
+  //
+  // NOTE: since no allocation is performed for the inlined vector in either
+  // case, the `noexcept(...)` specification depends on whether moving the
+  // underlying objects can throw. It is assumed assumed that...
+  //  a) move constructors should only throw due to allocation failure.
+  //  b) if `value_type`'s move constructor allocates, it uses the same
+  //     allocation function as the inlined vector's allocator.
+  // Thus, the move constructor is non-throwing if the allocator is non-throwing
+  // or `value_type`'s move constructor is specified as `noexcept`.
+  InlinedVector(InlinedVector&& other) noexcept(
+      absl::allocator_is_nothrow<allocator_type>::value ||
+      std::is_nothrow_move_constructible<value_type>::value)
+      : storage_(*other.storage_.GetAllocPtr()) {
+    if (IsMemcpyOk::value) {
+      storage_.MemcpyFrom(other.storage_);
+
+      other.storage_.SetInlinedSize(0);
+    } else if (other.storage_.GetIsAllocated()) {
+      storage_.SetAllocatedData(other.storage_.GetAllocatedData(),
+                                other.storage_.GetAllocatedCapacity());
+      storage_.SetAllocatedSize(other.storage_.GetSize());
+
+      other.storage_.SetInlinedSize(0);
+    } else {
+      IteratorValueAdapter<MoveIterator> other_values(
+          MoveIterator(other.storage_.GetInlinedData()));
+
+      inlined_vector_internal::ConstructElements(
+          storage_.GetAllocPtr(), storage_.GetInlinedData(), &other_values,
+          other.storage_.GetSize());
+
+      storage_.SetInlinedSize(other.storage_.GetSize());
+    }
+  }
+
+  // Creates an inlined vector by moving in the contents of `other` with a copy
+  // of `alloc`.
+  //
+  // NOTE: if `other`'s allocator is not equal to `alloc`, even if `other`
+  // contains allocated memory, this move constructor will still allocate. Since
+  // allocation is performed, this constructor can only be `noexcept` if the
+  // specified allocator is also `noexcept`.
+  InlinedVector(InlinedVector&& other, const allocator_type& alloc) noexcept(
+      absl::allocator_is_nothrow<allocator_type>::value)
+      : storage_(alloc) {
+    if (IsMemcpyOk::value) {
+      storage_.MemcpyFrom(other.storage_);
+
+      other.storage_.SetInlinedSize(0);
+    } else if ((*storage_.GetAllocPtr() == *other.storage_.GetAllocPtr()) &&
+               other.storage_.GetIsAllocated()) {
+      storage_.SetAllocatedData(other.storage_.GetAllocatedData(),
+                                other.storage_.GetAllocatedCapacity());
+      storage_.SetAllocatedSize(other.storage_.GetSize());
+
+      other.storage_.SetInlinedSize(0);
+    } else {
+      storage_.Initialize(
+          IteratorValueAdapter<MoveIterator>(MoveIterator(other.data())),
+          other.size());
+    }
+  }
+
+  ~InlinedVector() {}
+
+  // ---------------------------------------------------------------------------
+  // InlinedVector Member Accessors
+  // ---------------------------------------------------------------------------
+
+  // `InlinedVector::empty()`
+  //
+  // Returns whether the inlined vector contains no elements.
+  bool empty() const noexcept { return !size(); }
+
+  // `InlinedVector::size()`
+  //
+  // Returns the number of elements in the inlined vector.
+  size_type size() const noexcept { return storage_.GetSize(); }
+
+  // `InlinedVector::max_size()`
+  //
+  // Returns the maximum number of elements the inlined vector can hold.
+  size_type max_size() const noexcept {
+    // One bit of the size storage is used to indicate whether the inlined
+    // vector contains allocated memory. As a result, the maximum size that the
+    // inlined vector can express is half of the max for `size_type`.
+    return (std::numeric_limits<size_type>::max)() / 2;
+  }
+
+  // `InlinedVector::capacity()`
+  //
+  // Returns the number of elements that could be stored in the inlined vector
+  // without requiring a reallocation.
+  //
+  // NOTE: for most inlined vectors, `capacity()` should be equal to the
+  // template parameter `N`. For inlined vectors which exceed this capacity,
+  // they will no longer be inlined and `capacity()` will equal the capactity of
+  // the allocated memory.
+  size_type capacity() const noexcept {
+    return storage_.GetIsAllocated() ? storage_.GetAllocatedCapacity()
+                                     : storage_.GetInlinedCapacity();
+  }
+
+  // `InlinedVector::data()`
+  //
+  // Returns a `pointer` to the elements of the inlined vector. This pointer
+  // can be used to access and modify the contained elements.
+  //
+  // NOTE: only elements within [`data()`, `data() + size()`) are valid.
+  pointer data() noexcept {
+    return storage_.GetIsAllocated() ? storage_.GetAllocatedData()
+                                     : storage_.GetInlinedData();
+  }
+
+  // Overload of `InlinedVector::data()` that returns a `const_pointer` to the
+  // elements of the inlined vector. This pointer can be used to access but not
+  // modify the contained elements.
+  //
+  // NOTE: only elements within [`data()`, `data() + size()`) are valid.
+  const_pointer data() const noexcept {
+    return storage_.GetIsAllocated() ? storage_.GetAllocatedData()
+                                     : storage_.GetInlinedData();
+  }
+
+  // `InlinedVector::operator[](...)`
+  //
+  // Returns a `reference` to the `i`th element of the inlined vector.
+  reference operator[](size_type i) {
+    ABSL_HARDENING_ASSERT(i < size());
+    return data()[i];
+  }
+
+  // Overload of `InlinedVector::operator[](...)` that returns a
+  // `const_reference` to the `i`th element of the inlined vector.
+  const_reference operator[](size_type i) const {
+    ABSL_HARDENING_ASSERT(i < size());
+    return data()[i];
+  }
+
+  // `InlinedVector::at(...)`
+  //
+  // Returns a `reference` to the `i`th element of the inlined vector.
+  //
+  // NOTE: if `i` is not within the required range of `InlinedVector::at(...)`,
+  // in both debug and non-debug builds, `std::out_of_range` will be thrown.
+  reference at(size_type i) {
+    if (ABSL_PREDICT_FALSE(i >= size())) {
+      base_internal::ThrowStdOutOfRange(
+          "`InlinedVector::at(size_type)` failed bounds check");
+    }
+    return data()[i];
+  }
+
+  // Overload of `InlinedVector::at(...)` that returns a `const_reference` to
+  // the `i`th element of the inlined vector.
+  //
+  // NOTE: if `i` is not within the required range of `InlinedVector::at(...)`,
+  // in both debug and non-debug builds, `std::out_of_range` will be thrown.
+  const_reference at(size_type i) const {
+    if (ABSL_PREDICT_FALSE(i >= size())) {
+      base_internal::ThrowStdOutOfRange(
+          "`InlinedVector::at(size_type) const` failed bounds check");
+    }
+    return data()[i];
+  }
+
+  // `InlinedVector::front()`
+  //
+  // Returns a `reference` to the first element of the inlined vector.
+  reference front() {
+    ABSL_HARDENING_ASSERT(!empty());
+    return data()[0];
+  }
+
+  // Overload of `InlinedVector::front()` that returns a `const_reference` to
+  // the first element of the inlined vector.
+  const_reference front() const {
+    ABSL_HARDENING_ASSERT(!empty());
+    return data()[0];
+  }
+
+  // `InlinedVector::back()`
+  //
+  // Returns a `reference` to the last element of the inlined vector.
+  reference back() {
+    ABSL_HARDENING_ASSERT(!empty());
+    return data()[size() - 1];
+  }
+
+  // Overload of `InlinedVector::back()` that returns a `const_reference` to the
+  // last element of the inlined vector.
+  const_reference back() const {
+    ABSL_HARDENING_ASSERT(!empty());
+    return data()[size() - 1];
+  }
+
+  // `InlinedVector::begin()`
+  //
+  // Returns an `iterator` to the beginning of the inlined vector.
+  iterator begin() noexcept { return data(); }
+
+  // Overload of `InlinedVector::begin()` that returns a `const_iterator` to
+  // the beginning of the inlined vector.
+  const_iterator begin() const noexcept { return data(); }
+
+  // `InlinedVector::end()`
+  //
+  // Returns an `iterator` to the end of the inlined vector.
+  iterator end() noexcept { return data() + size(); }
+
+  // Overload of `InlinedVector::end()` that returns a `const_iterator` to the
+  // end of the inlined vector.
+  const_iterator end() const noexcept { return data() + size(); }
+
+  // `InlinedVector::cbegin()`
+  //
+  // Returns a `const_iterator` to the beginning of the inlined vector.
+  const_iterator cbegin() const noexcept { return begin(); }
+
+  // `InlinedVector::cend()`
+  //
+  // Returns a `const_iterator` to the end of the inlined vector.
+  const_iterator cend() const noexcept { return end(); }
+
+  // `InlinedVector::rbegin()`
+  //
+  // Returns a `reverse_iterator` from the end of the inlined vector.
+  reverse_iterator rbegin() noexcept { return reverse_iterator(end()); }
+
+  // Overload of `InlinedVector::rbegin()` that returns a
+  // `const_reverse_iterator` from the end of the inlined vector.
+  const_reverse_iterator rbegin() const noexcept {
+    return const_reverse_iterator(end());
+  }
+
+  // `InlinedVector::rend()`
+  //
+  // Returns a `reverse_iterator` from the beginning of the inlined vector.
+  reverse_iterator rend() noexcept { return reverse_iterator(begin()); }
+
+  // Overload of `InlinedVector::rend()` that returns a `const_reverse_iterator`
+  // from the beginning of the inlined vector.
+  const_reverse_iterator rend() const noexcept {
+    return const_reverse_iterator(begin());
+  }
+
+  // `InlinedVector::crbegin()`
+  //
+  // Returns a `const_reverse_iterator` from the end of the inlined vector.
+  const_reverse_iterator crbegin() const noexcept { return rbegin(); }
+
+  // `InlinedVector::crend()`
+  //
+  // Returns a `const_reverse_iterator` from the beginning of the inlined
+  // vector.
+  const_reverse_iterator crend() const noexcept { return rend(); }
+
+  // `InlinedVector::get_allocator()`
+  //
+  // Returns a copy of the inlined vector's allocator.
+  allocator_type get_allocator() const { return *storage_.GetAllocPtr(); }
+
+  // ---------------------------------------------------------------------------
+  // InlinedVector Member Mutators
+  // ---------------------------------------------------------------------------
+
+  // `InlinedVector::operator=(...)`
+  //
+  // Replaces the elements of the inlined vector with copies of the elements of
+  // `list`.
+  InlinedVector& operator=(std::initializer_list<value_type> list) {
+    assign(list.begin(), list.end());
+
+    return *this;
+  }
+
+  // Overload of `InlinedVector::operator=(...)` that replaces the elements of
+  // the inlined vector with copies of the elements of `other`.
+  InlinedVector& operator=(const InlinedVector& other) {
+    if (ABSL_PREDICT_TRUE(this != std::addressof(other))) {
+      const_pointer other_data = other.data();
+      assign(other_data, other_data + other.size());
+    }
+
+    return *this;
+  }
+
+  // Overload of `InlinedVector::operator=(...)` that moves the elements of
+  // `other` into the inlined vector.
+  //
+  // NOTE: as a result of calling this overload, `other` is left in a valid but
+  // unspecified state.
+  InlinedVector& operator=(InlinedVector&& other) {
+    if (ABSL_PREDICT_TRUE(this != std::addressof(other))) {
+      if (IsMemcpyOk::value || other.storage_.GetIsAllocated()) {
+        inlined_vector_internal::DestroyElements(storage_.GetAllocPtr(), data(),
+                                                 size());
+        storage_.DeallocateIfAllocated();
+        storage_.MemcpyFrom(other.storage_);
+
+        other.storage_.SetInlinedSize(0);
+      } else {
+        storage_.Assign(IteratorValueAdapter<MoveIterator>(
+                            MoveIterator(other.storage_.GetInlinedData())),
+                        other.size());
+      }
+    }
+
+    return *this;
+  }
+
+  // `InlinedVector::assign(...)`
+  //
+  // Replaces the contents of the inlined vector with `n` copies of `v`.
+  void assign(size_type n, const_reference v) {
+    storage_.Assign(CopyValueAdapter(v), n);
+  }
+
+  // Overload of `InlinedVector::assign(...)` that replaces the contents of the
+  // inlined vector with copies of the elements of `list`.
+  void assign(std::initializer_list<value_type> list) {
+    assign(list.begin(), list.end());
+  }
+
+  // Overload of `InlinedVector::assign(...)` to replace the contents of the
+  // inlined vector with the range [`first`, `last`).
+  //
+  // NOTE: this overload is for iterators that are "forward" category or better.
+  template <typename ForwardIterator,
+            EnableIfAtLeastForwardIterator<ForwardIterator>* = nullptr>
+  void assign(ForwardIterator first, ForwardIterator last) {
+    storage_.Assign(IteratorValueAdapter<ForwardIterator>(first),
+                    std::distance(first, last));
+  }
+
+  // Overload of `InlinedVector::assign(...)` to replace the contents of the
+  // inlined vector with the range [`first`, `last`).
+  //
+  // NOTE: this overload is for iterators that are "input" category.
+  template <typename InputIterator,
+            DisableIfAtLeastForwardIterator<InputIterator>* = nullptr>
+  void assign(InputIterator first, InputIterator last) {
+    size_type i = 0;
+    for (; i < size() && first != last; ++i, static_cast<void>(++first)) {
+      data()[i] = *first;
+    }
+
+    erase(data() + i, data() + size());
+    std::copy(first, last, std::back_inserter(*this));
+  }
+
+  // `InlinedVector::resize(...)`
+  //
+  // Resizes the inlined vector to contain `n` elements.
+  //
+  // NOTE: If `n` is smaller than `size()`, extra elements are destroyed. If `n`
+  // is larger than `size()`, new elements are value-initialized.
+  void resize(size_type n) {
+    ABSL_HARDENING_ASSERT(n <= max_size());
+    storage_.Resize(DefaultValueAdapter(), n);
+  }
+
+  // Overload of `InlinedVector::resize(...)` that resizes the inlined vector to
+  // contain `n` elements.
+  //
+  // NOTE: if `n` is smaller than `size()`, extra elements are destroyed. If `n`
+  // is larger than `size()`, new elements are copied-constructed from `v`.
+  void resize(size_type n, const_reference v) {
+    ABSL_HARDENING_ASSERT(n <= max_size());
+    storage_.Resize(CopyValueAdapter(v), n);
+  }
+
+  // `InlinedVector::insert(...)`
+  //
+  // Inserts a copy of `v` at `pos`, returning an `iterator` to the newly
+  // inserted element.
+  iterator insert(const_iterator pos, const_reference v) {
+    return emplace(pos, v);
+  }
+
+  // Overload of `InlinedVector::insert(...)` that inserts `v` at `pos` using
+  // move semantics, returning an `iterator` to the newly inserted element.
+  iterator insert(const_iterator pos, RValueReference v) {
+    return emplace(pos, std::move(v));
+  }
+
+  // Overload of `InlinedVector::insert(...)` that inserts `n` contiguous copies
+  // of `v` starting at `pos`, returning an `iterator` pointing to the first of
+  // the newly inserted elements.
+  iterator insert(const_iterator pos, size_type n, const_reference v) {
+    ABSL_HARDENING_ASSERT(pos >= begin());
+    ABSL_HARDENING_ASSERT(pos <= end());
+
+    if (ABSL_PREDICT_TRUE(n != 0)) {
+      value_type dealias = v;
+      return storage_.Insert(pos, CopyValueAdapter(dealias), n);
+    } else {
+      return const_cast<iterator>(pos);
+    }
+  }
+
+  // Overload of `InlinedVector::insert(...)` that inserts copies of the
+  // elements of `list` starting at `pos`, returning an `iterator` pointing to
+  // the first of the newly inserted elements.
+  iterator insert(const_iterator pos, std::initializer_list<value_type> list) {
+    return insert(pos, list.begin(), list.end());
+  }
+
+  // Overload of `InlinedVector::insert(...)` that inserts the range [`first`,
+  // `last`) starting at `pos`, returning an `iterator` pointing to the first
+  // of the newly inserted elements.
+  //
+  // NOTE: this overload is for iterators that are "forward" category or better.
+  template <typename ForwardIterator,
+            EnableIfAtLeastForwardIterator<ForwardIterator>* = nullptr>
+  iterator insert(const_iterator pos, ForwardIterator first,
+                  ForwardIterator last) {
+    ABSL_HARDENING_ASSERT(pos >= begin());
+    ABSL_HARDENING_ASSERT(pos <= end());
+
+    if (ABSL_PREDICT_TRUE(first != last)) {
+      return storage_.Insert(pos, IteratorValueAdapter<ForwardIterator>(first),
+                             std::distance(first, last));
+    } else {
+      return const_cast<iterator>(pos);
+    }
+  }
+
+  // Overload of `InlinedVector::insert(...)` that inserts the range [`first`,
+  // `last`) starting at `pos`, returning an `iterator` pointing to the first
+  // of the newly inserted elements.
+  //
+  // NOTE: this overload is for iterators that are "input" category.
+  template <typename InputIterator,
+            DisableIfAtLeastForwardIterator<InputIterator>* = nullptr>
+  iterator insert(const_iterator pos, InputIterator first, InputIterator last) {
+    ABSL_HARDENING_ASSERT(pos >= begin());
+    ABSL_HARDENING_ASSERT(pos <= end());
+
+    size_type index = std::distance(cbegin(), pos);
+    for (size_type i = index; first != last; ++i, static_cast<void>(++first)) {
+      insert(data() + i, *first);
+    }
+
+    return iterator(data() + index);
+  }
+
+  // `InlinedVector::emplace(...)`
+  //
+  // Constructs and inserts an element using `args...` in the inlined vector at
+  // `pos`, returning an `iterator` pointing to the newly emplaced element.
+  template <typename... Args>
+  iterator emplace(const_iterator pos, Args&&... args) {
+    ABSL_HARDENING_ASSERT(pos >= begin());
+    ABSL_HARDENING_ASSERT(pos <= end());
+
+    value_type dealias(std::forward<Args>(args)...);
+    return storage_.Insert(pos,
+                           IteratorValueAdapter<MoveIterator>(
+                               MoveIterator(std::addressof(dealias))),
+                           1);
+  }
+
+  // `InlinedVector::emplace_back(...)`
+  //
+  // Constructs and inserts an element using `args...` in the inlined vector at
+  // `end()`, returning a `reference` to the newly emplaced element.
+  template <typename... Args>
+  reference emplace_back(Args&&... args) {
+    return storage_.EmplaceBack(std::forward<Args>(args)...);
+  }
+
+  // `InlinedVector::push_back(...)`
+  //
+  // Inserts a copy of `v` in the inlined vector at `end()`.
+  void push_back(const_reference v) { static_cast<void>(emplace_back(v)); }
+
+  // Overload of `InlinedVector::push_back(...)` for inserting `v` at `end()`
+  // using move semantics.
+  void push_back(RValueReference v) {
+    static_cast<void>(emplace_back(std::move(v)));
+  }
+
+  // `InlinedVector::pop_back()`
+  //
+  // Destroys the element at `back()`, reducing the size by `1`.
+  void pop_back() noexcept {
+    ABSL_HARDENING_ASSERT(!empty());
+
+    AllocatorTraits::destroy(*storage_.GetAllocPtr(), data() + (size() - 1));
+    storage_.SubtractSize(1);
+  }
+
+  // `InlinedVector::erase(...)`
+  //
+  // Erases the element at `pos`, returning an `iterator` pointing to where the
+  // erased element was located.
+  //
+  // NOTE: may return `end()`, which is not dereferencable.
+  iterator erase(const_iterator pos) {
+    ABSL_HARDENING_ASSERT(pos >= begin());
+    ABSL_HARDENING_ASSERT(pos < end());
+
+    return storage_.Erase(pos, pos + 1);
+  }
+
+  // Overload of `InlinedVector::erase(...)` that erases every element in the
+  // range [`from`, `to`), returning an `iterator` pointing to where the first
+  // erased element was located.
+  //
+  // NOTE: may return `end()`, which is not dereferencable.
+  iterator erase(const_iterator from, const_iterator to) {
+    ABSL_HARDENING_ASSERT(from >= begin());
+    ABSL_HARDENING_ASSERT(from <= to);
+    ABSL_HARDENING_ASSERT(to <= end());
+
+    if (ABSL_PREDICT_TRUE(from != to)) {
+      return storage_.Erase(from, to);
+    } else {
+      return const_cast<iterator>(from);
+    }
+  }
+
+  // `InlinedVector::clear()`
+  //
+  // Destroys all elements in the inlined vector, setting the size to `0` and
+  // deallocating any held memory.
+  void clear() noexcept {
+    inlined_vector_internal::DestroyElements(storage_.GetAllocPtr(), data(),
+                                             size());
+    storage_.DeallocateIfAllocated();
+
+    storage_.SetInlinedSize(0);
+  }
+
+  // `InlinedVector::reserve(...)`
+  //
+  // Ensures that there is enough room for at least `n` elements.
+  void reserve(size_type n) { storage_.Reserve(n); }
+
+  // `InlinedVector::shrink_to_fit()`
+  //
+  // Reduces memory usage by freeing unused memory. After being called, calls to
+  // `capacity()` will be equal to `max(N, size())`.
+  //
+  // If `size() <= N` and the inlined vector contains allocated memory, the
+  // elements will all be moved to the inlined space and the allocated memory
+  // will be deallocated.
+  //
+  // If `size() > N` and `size() < capacity()`, the elements will be moved to a
+  // smaller allocation.
+  void shrink_to_fit() {
+    if (storage_.GetIsAllocated()) {
+      storage_.ShrinkToFit();
+    }
+  }
+
+  // `InlinedVector::swap(...)`
+  //
+  // Swaps the contents of the inlined vector with `other`.
+  void swap(InlinedVector& other) {
+    if (ABSL_PREDICT_TRUE(this != std::addressof(other))) {
+      storage_.Swap(std::addressof(other.storage_));
+    }
+  }
+
+ private:
+  template <typename H, typename TheT, size_t TheN, typename TheA>
+  friend H AbslHashValue(H h, const absl::InlinedVector<TheT, TheN, TheA>& a);
+
+  Storage storage_;
+};
+
+// -----------------------------------------------------------------------------
+// InlinedVector Non-Member Functions
+// -----------------------------------------------------------------------------
+
+// `swap(...)`
+//
+// Swaps the contents of two inlined vectors.
+template <typename T, size_t N, typename A>
+void swap(absl::InlinedVector<T, N, A>& a,
+          absl::InlinedVector<T, N, A>& b) noexcept(noexcept(a.swap(b))) {
+  a.swap(b);
+}
+
+// `operator==(...)`
+//
+// Tests for value-equality of two inlined vectors.
+template <typename T, size_t N, typename A>
+bool operator==(const absl::InlinedVector<T, N, A>& a,
+                const absl::InlinedVector<T, N, A>& b) {
+  auto a_data = a.data();
+  auto b_data = b.data();
+  return absl::equal(a_data, a_data + a.size(), b_data, b_data + b.size());
+}
+
+// `operator!=(...)`
+//
+// Tests for value-inequality of two inlined vectors.
+template <typename T, size_t N, typename A>
+bool operator!=(const absl::InlinedVector<T, N, A>& a,
+                const absl::InlinedVector<T, N, A>& b) {
+  return !(a == b);
+}
+
+// `operator<(...)`
+//
+// Tests whether the value of an inlined vector is less than the value of
+// another inlined vector using a lexicographical comparison algorithm.
+template <typename T, size_t N, typename A>
+bool operator<(const absl::InlinedVector<T, N, A>& a,
+               const absl::InlinedVector<T, N, A>& b) {
+  auto a_data = a.data();
+  auto b_data = b.data();
+  return std::lexicographical_compare(a_data, a_data + a.size(), b_data,
+                                      b_data + b.size());
+}
+
+// `operator>(...)`
+//
+// Tests whether the value of an inlined vector is greater than the value of
+// another inlined vector using a lexicographical comparison algorithm.
+template <typename T, size_t N, typename A>
+bool operator>(const absl::InlinedVector<T, N, A>& a,
+               const absl::InlinedVector<T, N, A>& b) {
+  return b < a;
+}
+
+// `operator<=(...)`
+//
+// Tests whether the value of an inlined vector is less than or equal to the
+// value of another inlined vector using a lexicographical comparison algorithm.
+template <typename T, size_t N, typename A>
+bool operator<=(const absl::InlinedVector<T, N, A>& a,
+                const absl::InlinedVector<T, N, A>& b) {
+  return !(b < a);
+}
+
+// `operator>=(...)`
+//
+// Tests whether the value of an inlined vector is greater than or equal to the
+// value of another inlined vector using a lexicographical comparison algorithm.
+template <typename T, size_t N, typename A>
+bool operator>=(const absl::InlinedVector<T, N, A>& a,
+                const absl::InlinedVector<T, N, A>& b) {
+  return !(a < b);
+}
+
+// `AbslHashValue(...)`
+//
+// Provides `absl::Hash` support for `absl::InlinedVector`. It is uncommon to
+// call this directly.
+template <typename H, typename T, size_t N, typename A>
+H AbslHashValue(H h, const absl::InlinedVector<T, N, A>& a) {
+  auto size = a.size();
+  return H::combine(H::combine_contiguous(std::move(h), a.data(), size), size);
+}
+
+ABSL_NAMESPACE_END
+}  // namespace absl
+
+#endif  // ABSL_CONTAINER_INLINED_VECTOR_H_