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// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___MEMORY_ASSUME_ALIGNED_H
#define _LIBCPP___MEMORY_ASSUME_ALIGNED_H
#include <__assert>
#include <__config>
#include <cstddef>
#include <cstdint>
#include <type_traits> // for is_constant_evaluated()
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER > 17
template <size_t _Np, class _Tp>
[[nodiscard]]
_LIBCPP_HIDE_FROM_ABI
constexpr _Tp* assume_aligned(_Tp* __ptr) {
static_assert(_Np != 0 && (_Np & (_Np - 1)) == 0,
"std::assume_aligned<N>(p) requires N to be a power of two");
if (is_constant_evaluated()) {
return __ptr;
} else {
_LIBCPP_ASSERT(reinterpret_cast<uintptr_t>(__ptr) % _Np == 0, "Alignment assumption is violated");
return static_cast<_Tp*>(__builtin_assume_aligned(__ptr, _Np));
}
}
#endif // _LIBCPP_STD_VER > 17
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___MEMORY_ASSUME_ALIGNED_H
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