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___TYPE_TRAITS_MAKE_SIGNED_H
10 #define _LIBCPP___TYPE_TRAITS_MAKE_SIGNED_H
11 
12 #include <__config>
13 #include <__type_traits/apply_cv.h>
14 #include <__type_traits/is_enum.h>
15 #include <__type_traits/is_integral.h>
16 #include <__type_traits/nat.h>
17 #include <__type_traits/remove_cv.h>
18 #include <__type_traits/type_list.h>
19 
20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
21 #  pragma GCC system_header
22 #endif
23 
24 _LIBCPP_BEGIN_NAMESPACE_STD
25 
26 #if __has_builtin(__make_signed)
27 
28 template <class _Tp>
29 using __make_signed_t = __make_signed(_Tp);
30 
31 #else
32 // clang-format off
33 typedef __type_list<signed char,
34         __type_list<signed short,
35         __type_list<signed int,
36         __type_list<signed long,
37         __type_list<signed long long,
38 #  ifndef _LIBCPP_HAS_NO_INT128
39         __type_list<__int128_t,
40 #  endif
41         __nat
42 #  ifndef _LIBCPP_HAS_NO_INT128
43         >
44 #  endif
45         > > > > > __signed_types;
46 // clang-format on
47 
48 template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
49 struct __make_signed{};
50 
51 template <class _Tp>
52 struct __make_signed<_Tp, true> {
53   typedef typename __find_first<__signed_types, sizeof(_Tp)>::type type;
54 };
55 
56 // clang-format off
57 template <> struct __make_signed<bool,               true> {};
58 template <> struct __make_signed<  signed short,     true> {typedef short     type;};
59 template <> struct __make_signed<unsigned short,     true> {typedef short     type;};
60 template <> struct __make_signed<  signed int,       true> {typedef int       type;};
61 template <> struct __make_signed<unsigned int,       true> {typedef int       type;};
62 template <> struct __make_signed<  signed long,      true> {typedef long      type;};
63 template <> struct __make_signed<unsigned long,      true> {typedef long      type;};
64 template <> struct __make_signed<  signed long long, true> {typedef long long type;};
65 template <> struct __make_signed<unsigned long long, true> {typedef long long type;};
66 #  ifndef _LIBCPP_HAS_NO_INT128
67 template <> struct __make_signed<__int128_t,         true> {typedef __int128_t type;};
68 template <> struct __make_signed<__uint128_t,        true> {typedef __int128_t type;};
69 #  endif
70 // clang-format on
71 
72 template <class _Tp>
73 using __make_signed_t = __apply_cv_t<_Tp, typename __make_signed<__remove_cv_t<_Tp> >::type>;
74 
75 #endif // __has_builtin(__make_signed)
76 
77 template <class _Tp>
78 struct make_signed {
79   using type _LIBCPP_NODEBUG = __make_signed_t<_Tp>;
80 };
81 
82 #if _LIBCPP_STD_VER >= 14
83 template <class _Tp>
84 using make_signed_t = __make_signed_t<_Tp>;
85 #endif
86 
87 _LIBCPP_END_NAMESPACE_STD
88 
89 #endif // _LIBCPP___TYPE_TRAITS_MAKE_SIGNED_H
90