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1// -*- C++ -*-2//===----------------------------------------------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___CXX03___MEMORY_ASSUME_ALIGNED_H11#define _LIBCPP___CXX03___MEMORY_ASSUME_ALIGNED_H12 13#include <__cxx03/__assert>14#include <__cxx03/__config>15#include <__cxx03/__type_traits/is_constant_evaluated.h>16#include <__cxx03/cstddef>17#include <__cxx03/cstdint>18 19#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)20# pragma GCC system_header21#endif22 23_LIBCPP_BEGIN_NAMESPACE_STD24 25template <size_t _Np, class _Tp>26_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _Tp* __assume_aligned(_Tp* __ptr) {27 static_assert(_Np != 0 && (_Np & (_Np - 1)) == 0, "std::assume_aligned<N>(p) requires N to be a power of two");28 29 if (__libcpp_is_constant_evaluated()) {30 (void)__builtin_assume_aligned(__ptr, _Np);31 return __ptr;32 } else {33 _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(34 reinterpret_cast<uintptr_t>(__ptr) % _Np == 0, "Alignment assumption is violated");35 return static_cast<_Tp*>(__builtin_assume_aligned(__ptr, _Np));36 }37}38 39_LIBCPP_END_NAMESPACE_STD40 41#endif // _LIBCPP___CXX03___MEMORY_ASSUME_ALIGNED_H42