105 lines
2.9 KiB
C++
105 lines
2.9 KiB
C++
/*
|
|
* Copyright (c) Facebook, Inc. and its affiliates.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <cstddef>
|
|
#include <type_traits>
|
|
#include <utility>
|
|
|
|
#include <folly/Utility.h>
|
|
#include <folly/lang/Align.h>
|
|
|
|
namespace folly {
|
|
|
|
template <typename T, std::size_t Align>
|
|
class aligned {
|
|
static_assert(!(Align & (Align - 1)), "alignment not a power of two");
|
|
static_assert(alignof(T) <= Align, "alignment too small");
|
|
|
|
public:
|
|
using alignment = index_constant<Align>;
|
|
using value_type = T;
|
|
|
|
aligned() = default;
|
|
aligned(aligned const&) = default;
|
|
aligned(aligned&&) = default;
|
|
template <
|
|
typename S = T,
|
|
std::enable_if_t<std::is_copy_constructible<S>::value, int> = 0>
|
|
aligned(T const& value) noexcept(std::is_nothrow_copy_constructible<T>::value)
|
|
: value_(value) {}
|
|
template <
|
|
typename S = T,
|
|
std::enable_if_t<std::is_move_constructible<S>::value, int> = 0>
|
|
aligned(T&& value) noexcept(std::is_nothrow_move_constructible<T>::value)
|
|
: value_(static_cast<T&&>(value)) {}
|
|
template <
|
|
typename... A,
|
|
std::enable_if_t<std::is_constructible<T, A...>::value, int> = 0>
|
|
explicit aligned(in_place_t, A&&... a) noexcept(
|
|
std::is_nothrow_constructible<T, A...>::value)
|
|
: value_(static_cast<A&&>(a)...) {}
|
|
|
|
aligned& operator=(aligned const&) = default;
|
|
aligned& operator=(aligned&&) = default;
|
|
template <
|
|
typename S = T,
|
|
std::enable_if_t<std::is_copy_assignable<S>::value, int> = 0>
|
|
aligned& operator=(T const& value) noexcept(
|
|
std::is_nothrow_copy_assignable<T>::value) {
|
|
value_ = value;
|
|
return *this;
|
|
}
|
|
template <
|
|
typename S = T,
|
|
std::enable_if_t<std::is_move_assignable<S>::value, int> = 0>
|
|
aligned& operator=(T&& value) noexcept(
|
|
std::is_nothrow_move_assignable<T>::value) {
|
|
value_ = std::move(value);
|
|
return *this;
|
|
}
|
|
|
|
T* get() noexcept {
|
|
return &value_;
|
|
}
|
|
T const* get() const noexcept {
|
|
return &value_;
|
|
}
|
|
T* operator->() noexcept {
|
|
return &value_;
|
|
}
|
|
T const* operator->() const noexcept {
|
|
return &value_;
|
|
}
|
|
T& operator*() noexcept {
|
|
return value_;
|
|
}
|
|
T const& operator*() const noexcept {
|
|
return value_;
|
|
}
|
|
|
|
private:
|
|
alignas(Align) T value_;
|
|
};
|
|
|
|
template <typename T>
|
|
using cacheline_aligned = aligned<
|
|
T,
|
|
(cacheline_align_v < alignof(T) ? alignof(T) : cacheline_align_v)>;
|
|
|
|
} // namespace folly
|