libcxx/include/__utility/convert_to_integral.h

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef _LIBCPP___UTILITY_CONVERT_TO_INTEGRAL_H
  10 #define _LIBCPP___UTILITY_CONVERT_TO_INTEGRAL_H
  11
  12 #include <__config>
  13 #include <__type_traits/enable_if.h>
  14 #include <__type_traits/is_enum.h>
  15 #include <__type_traits/is_floating_point.h>
  16 #include <__type_traits/underlying_type.h>
  17
  18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  19 #  pragma GCC system_header
  20 #endif
  21
  22 _LIBCPP_BEGIN_NAMESPACE_STD
  23
  24 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  25 int __convert_to_integral(int __val) { return __val; }
  26
  27 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  28 unsigned __convert_to_integral(unsigned __val) { return __val; }
  29
  30 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  31 long __convert_to_integral(long __val) { return __val; }
  32
  33 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  34 unsigned long __convert_to_integral(unsigned long __val) { return __val; }
  35
  36 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  37 long long __convert_to_integral(long long __val) { return __val; }
  38
  39 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  40 unsigned long long __convert_to_integral(unsigned long long __val) {return __val; }
  41
  42 template<typename _Fp, __enable_if_t<is_floating_point<_Fp>::value, int> = 0>
  43 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  44 long long
  45  __convert_to_integral(_Fp __val) { return __val; }
  46
  47 #ifndef _LIBCPP_HAS_NO_INT128
  48 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  49 __int128_t __convert_to_integral(__int128_t __val) { return __val; }
  50
  51 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  52 __uint128_t __convert_to_integral(__uint128_t __val) { return __val; }
  53 #endif
  54
  55 template <class _Tp, bool = is_enum<_Tp>::value>
  56 struct __sfinae_underlying_type
  57 {
  58     typedef typename underlying_type<_Tp>::type type;
  59     typedef decltype(((type)1) + 0) __promoted_type;
  60 };
  61
  62 template <class _Tp>
  63 struct __sfinae_underlying_type<_Tp, false> {};
  64
  65 template <class _Tp>
  66 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
  67 typename __sfinae_underlying_type<_Tp>::__promoted_type
  68 __convert_to_integral(_Tp __val) { return __val; }
  69
  70 _LIBCPP_END_NAMESPACE_STD
  71
  72 #endif // _LIBCPP___UTILITY_CONVERT_TO_INTEGRAL_H