//===-- llvm/ADT/bit.h - C++20 <bit> ----------------------------*- 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 implements the C++20 <bit> header.

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_ADT_BIT_H

#define LLVM_ADT_BIT_H

#include "llvm/Support/Compiler.h"

#include <cstring>

#include <type_traits>

namespace llvm {

// This implementation of bit_cast is different from the C++17 one in two ways:

//  - It isn't constexpr because that requires compiler support.

//  - It requires trivially-constructible To, to avoid UB in the implementation.

template <

    typename To, typename From,

    typename = std::enable_if_t<sizeof(To) == sizeof(From)>

#if (__has_feature(is_trivially_constructible) && defined(_LIBCPP_VERSION)) || \

    (defined(__GNUC__) && __GNUC__ >= 5)

    ,

    typename = std::enable_if_t<std::is_trivially_constructible<To>::value>

#elif __has_feature(is_trivially_constructible)

    ,

    typename = std::enable_if_t<__is_trivially_constructible(To)>

#else

  // See comment below.

#endif

#if (__has_feature(is_trivially_copyable) && defined(_LIBCPP_VERSION)) || \

    (defined(__GNUC__) && __GNUC__ >= 5)

    ,

    typename = std::enable_if_t<std::is_trivially_copyable<To>::value>,

    typename = std::enable_if_t<std::is_trivially_copyable<From>::value>

#elif __has_feature(is_trivially_copyable)

    ,

    typename = std::enable_if_t<__is_trivially_copyable(To)>,

    typename = std::enable_if_t<__is_trivially_copyable(From)>

#else

// This case is GCC 4.x. clang with libc++ or libstdc++ never get here. Unlike

// llvm/Support/type_traits.h's is_trivially_copyable we don't want to

// provide a good-enough answer here: developers in that configuration will hit

// compilation failures on the bots instead of locally. That's acceptable

// because it's very few developers, and only until we move past C++11.

#endif

    >

inline To bit_cast(const From &from) noexcept {

  To to;

  std::memcpy(&to, &from, sizeof(To));

  return to;

}

Unexecuted instantiation: _ZN4llvm8bit_castImdvvvvEET_RKT0_

Unexecuted instantiation: _ZN4llvm8bit_castIdmvvvvEET_RKT0_

Unexecuted instantiation: _ZN4llvm8bit_castIjN4mlir6detail18IntegerTypeStorage7KeyBitsEvvvvEET_RKT0_

Unexecuted instantiation: _ZN4llvm8bit_castIN4mlir6detail18IntegerTypeStorage7KeyBitsEjvvvvEET_RKT0_

} // namespace llvm

#endif