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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* Functionality related to memory alignment. */
#ifndef mozilla_Alignment_h
#define mozilla_Alignment_h
#include "mozilla/Attributes.h"
#include <cstddef>
#include <cstdint>
namespace mozilla {
/*
* AlignedElem<N> is a structure whose alignment is guaranteed to be at least N
* bytes.
*/
template <size_t Align>
struct alignas(Align) AlignedElem {};
template <typename T>
struct MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS AlignedStorage2 {
union {
unsigned char mBytes[sizeof(T)];
uint64_t mDummy;
};
const T* addr() const { return reinterpret_cast<const T*>(mBytes); }
T* addr() { return static_cast<T*>(static_cast<void*>(mBytes)); }
const void* bytes() const { return static_cast<const void*>(mBytes); }
void* bytes() { return static_cast<void*>(mBytes); }
AlignedStorage2() = default;
// AlignedStorage2 is non-copyable: the default copy constructor violates
// strict aliasing rules, per bug 1269319.
AlignedStorage2(const AlignedStorage2&) = delete;
void operator=(const AlignedStorage2&) = delete;
};
} /* namespace mozilla */
#endif /* mozilla_Alignment_h */
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