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 typedef
33     __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 
47 template <class _Tp, bool = is_integral<_Tp>::value || is_enum<_Tp>::value>
48 struct __make_signed {};
49 
50 template <class _Tp>
51 struct __make_signed<_Tp, true>
52 {
53     typedef typename __find_first<__signed_types, sizeof(_Tp)>::type type;
54 };
55 
56 template <> struct __make_signed<bool,               true> {};
57 template <> struct __make_signed<  signed short,     true> {typedef short     type;};
58 template <> struct __make_signed<unsigned short,     true> {typedef short     type;};
59 template <> struct __make_signed<  signed int,       true> {typedef int       type;};
60 template <> struct __make_signed<unsigned int,       true> {typedef int       type;};
61 template <> struct __make_signed<  signed long,      true> {typedef long      type;};
62 template <> struct __make_signed<unsigned long,      true> {typedef long      type;};
63 template <> struct __make_signed<  signed long long, true> {typedef long long type;};
64 template <> struct __make_signed<unsigned long long, true> {typedef long long type;};
65 #  ifndef _LIBCPP_HAS_NO_INT128
66 template <> struct __make_signed<__int128_t,         true> {typedef __int128_t type;};
67 template <> struct __make_signed<__uint128_t,        true> {typedef __int128_t type;};
68 #  endif
69 
70 template <class _Tp>
71 using __make_signed_t = typename __apply_cv<_Tp, typename __make_signed<__remove_cv_t<_Tp> >::type>::type;
72 
73 #endif // __has_builtin(__make_signed)
74 
75 template <class _Tp>
76 struct make_signed {
77   using type _LIBCPP_NODEBUG = __make_signed_t<_Tp>;
78 };
79 
80 #if _LIBCPP_STD_VER > 11
81 template <class _Tp> using make_signed_t = __make_signed_t<_Tp>;
82 #endif
83 
84 _LIBCPP_END_NAMESPACE_STD
85 
86 #endif // _LIBCPP___TYPE_TRAITS_MAKE_SIGNED_H
87