lib/orc/stl_extras.h

//===-------- stl_extras.h - Useful STL related functions-------*- 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
//
//===----------------------------------------------------------------------===//
//
// This file is a part of the ORC runtime support library.
//
//===----------------------------------------------------------------------===//

#ifndef ORC_RT_STL_EXTRAS_H
#define ORC_RT_STL_EXTRAS_H

#include <cstdint>
#include <utility>
#include <tuple>

namespace orc_rt {

/// Substitute for std::identity.
/// Switch to std::identity once we can use c++20.
template <class Ty> struct identity {
  using is_transparent = void;
  using argument_type = Ty;

  Ty &operator()(Ty &self) const { return self; }
  const Ty &operator()(const Ty &self) const { return self; }
};

/// Substitute for std::bit_ceil.
constexpr uint64_t bit_ceil(uint64_t Val) noexcept {
  Val |= (Val >> 1);
  Val |= (Val >> 2);
  Val |= (Val >> 4);
  Val |= (Val >> 8);
  Val |= (Val >> 16);
  Val |= (Val >> 32);
  return Val + 1;
}

} // namespace orc_rt

#endif // ORC_RT_STL_EXTRAS