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 // UNSUPPORTED: c++03, c++11, c++14, c++17
10 // <numeric>
11 
12 // template <class _Tp>
13 // _Tp midpoint(_Tp __a, _Tp __b) noexcept
14 //
15 
16 #include <stdint.h>
17 #include <limits>
18 #include <numeric>
19 #include <cassert>
20 #include "test_macros.h"
21 
22 template <typename T>
signed_test()23 void signed_test()
24 {
25     constexpr T zero{0};
26     constexpr T one{1};
27     constexpr T two{2};
28     constexpr T three{3};
29     constexpr T four{4};
30 
31     ASSERT_SAME_TYPE(decltype(std::midpoint(T(), T())), T);
32     ASSERT_NOEXCEPT(          std::midpoint(T(), T()));
33     using limits = std::numeric_limits<T>;
34 
35     static_assert(std::midpoint(one, three) == two, "");
36     static_assert(std::midpoint(three, one) == two, "");
37 
38     assert(std::midpoint(zero, zero) == zero);
39     assert(std::midpoint(zero, two)  == one);
40     assert(std::midpoint(two, zero)  == one);
41     assert(std::midpoint(two, two)   == two);
42 
43     assert(std::midpoint(one, four)    == two);
44     assert(std::midpoint(four, one)    == three);
45     assert(std::midpoint(three, four)  == three);
46     assert(std::midpoint(four, three)  == four);
47 
48     assert(std::midpoint(T( 3), T( 4)) == T(3));
49     assert(std::midpoint(T( 4), T( 3)) == T(4));
50     assert(std::midpoint(T(-3), T( 4)) == T(0));
51     assert(std::midpoint(T(-4), T( 3)) == T(-1));
52     assert(std::midpoint(T( 3), T(-4)) == T(0));
53     assert(std::midpoint(T( 4), T(-3)) == T(1));
54     assert(std::midpoint(T(-3), T(-4)) == T(-3));
55     assert(std::midpoint(T(-4), T(-3)) == T(-4));
56 
57     static_assert(std::midpoint(limits::min(), limits::max()) == T(-1), "");
58     static_assert(std::midpoint(limits::max(), limits::min()) == T( 0), "");
59 
60     static_assert(std::midpoint(limits::min(), T(6)) == limits::min()/2 + 3, "");
61     assert(       std::midpoint(T(6), limits::min()) == limits::min()/2 + 3);
62     assert(       std::midpoint(limits::max(), T(6)) == limits::max()/2 + 4);
63     static_assert(std::midpoint(T(6), limits::max()) == limits::max()/2 + 3, "");
64 
65     assert(       std::midpoint(limits::min(), T(-6)) == limits::min()/2 - 3);
66     static_assert(std::midpoint(T(-6), limits::min()) == limits::min()/2 - 3, "");
67     static_assert(std::midpoint(limits::max(), T(-6)) == limits::max()/2 - 2, "");
68     assert(       std::midpoint(T(-6), limits::max()) == limits::max()/2 - 3);
69 }
70 
71 template <typename T>
unsigned_test()72 void unsigned_test()
73 {
74     constexpr T zero{0};
75     constexpr T one{1};
76     constexpr T two{2};
77     constexpr T three{3};
78     constexpr T four{4};
79 
80     ASSERT_SAME_TYPE(decltype(std::midpoint(T(), T())), T);
81     ASSERT_NOEXCEPT(          std::midpoint(T(), T()));
82     using limits = std::numeric_limits<T>;
83     const T half_way = (limits::max() - limits::min())/2;
84 
85     static_assert(std::midpoint(one, three) == two, "");
86     static_assert(std::midpoint(three, one) == two, "");
87 
88     assert(std::midpoint(zero, zero) == zero);
89     assert(std::midpoint(zero, two)  == one);
90     assert(std::midpoint(two, zero)  == one);
91     assert(std::midpoint(two, two)   == two);
92 
93     assert(std::midpoint(one, four)    == two);
94     assert(std::midpoint(four, one)    == three);
95     assert(std::midpoint(three, four)  == three);
96     assert(std::midpoint(four, three)  == four);
97 
98     assert(std::midpoint(limits::min(), limits::max()) == T(half_way));
99     assert(std::midpoint(limits::max(), limits::min()) == T(half_way + 1));
100 
101     static_assert(std::midpoint(limits::min(), T(6)) == limits::min()/2 + 3, "");
102     assert(       std::midpoint(T(6), limits::min()) == limits::min()/2 + 3);
103     assert(       std::midpoint(limits::max(), T(6)) == half_way + 4);
104     static_assert(std::midpoint(T(6), limits::max()) == half_way + 3, "");
105 }
106 
107 
main(int,char **)108 int main(int, char**)
109 {
110     signed_test<signed char>();
111     signed_test<short>();
112     signed_test<int>();
113     signed_test<long>();
114     signed_test<long long>();
115 
116     signed_test<int8_t>();
117     signed_test<int16_t>();
118     signed_test<int32_t>();
119     signed_test<int64_t>();
120 
121     unsigned_test<unsigned char>();
122     unsigned_test<unsigned short>();
123     unsigned_test<unsigned int>();
124     unsigned_test<unsigned long>();
125     unsigned_test<unsigned long long>();
126 
127     unsigned_test<uint8_t>();
128     unsigned_test<uint16_t>();
129     unsigned_test<uint32_t>();
130     unsigned_test<uint64_t>();
131 
132 #ifndef _LIBCPP_HAS_NO_INT128
133     unsigned_test<__uint128_t>();
134     signed_test<__int128_t>();
135 #endif
136 
137 //     int_test<char>();
138     signed_test<ptrdiff_t>();
139     unsigned_test<size_t>();
140 
141     return 0;
142 }
143