lcm.pass.cpp
5.18 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// UNSUPPORTED: c++98, c++03, c++11, c++14
// <numeric>
// template<class _M, class _N>
// constexpr common_type_t<_M,_N> lcm(_M __m, _N __n)
#include <numeric>
#include <cassert>
#include <climits>
#include <cstdint>
#include <cstdlib>
#include <type_traits>
#include "test_macros.h"
constexpr struct {
int x;
int y;
int expect;
} Cases[] = {
{0, 0, 0},
{1, 0, 0},
{0, 1, 0},
{1, 1, 1},
{2, 3, 6},
{2, 4, 4},
{3, 17, 51},
{36, 18, 36}
};
template <typename Input1, typename Input2, typename Output>
constexpr bool test0(int in1, int in2, int out)
{
auto value1 = static_cast<Input1>(in1);
auto value2 = static_cast<Input2>(in2);
static_assert(std::is_same_v<Output, decltype(std::lcm(value1, value2))>, "");
static_assert(std::is_same_v<Output, decltype(std::lcm(value2, value1))>, "");
assert(static_cast<Output>(out) == std::lcm(value1, value2));
return true;
}
template <typename Input1, typename Input2 = Input1>
constexpr bool do_test(int = 0)
{
using S1 = std::make_signed_t<Input1>;
using S2 = std::make_signed_t<Input2>;
using U1 = std::make_unsigned_t<Input1>;
using U2 = std::make_unsigned_t<Input2>;
bool accumulate = true;
for (auto TC : Cases) {
{ // Test with two signed types
using Output = std::common_type_t<S1, S2>;
accumulate &= test0<S1, S2, Output>(TC.x, TC.y, TC.expect);
accumulate &= test0<S1, S2, Output>(-TC.x, TC.y, TC.expect);
accumulate &= test0<S1, S2, Output>(TC.x, -TC.y, TC.expect);
accumulate &= test0<S1, S2, Output>(-TC.x, -TC.y, TC.expect);
accumulate &= test0<S2, S1, Output>(TC.x, TC.y, TC.expect);
accumulate &= test0<S2, S1, Output>(-TC.x, TC.y, TC.expect);
accumulate &= test0<S2, S1, Output>(TC.x, -TC.y, TC.expect);
accumulate &= test0<S2, S1, Output>(-TC.x, -TC.y, TC.expect);
}
{ // test with two unsigned types
using Output = std::common_type_t<U1, U2>;
accumulate &= test0<U1, U2, Output>(TC.x, TC.y, TC.expect);
accumulate &= test0<U2, U1, Output>(TC.x, TC.y, TC.expect);
}
{ // Test with mixed signs
using Output = std::common_type_t<S1, U2>;
accumulate &= test0<S1, U2, Output>(TC.x, TC.y, TC.expect);
accumulate &= test0<U2, S1, Output>(TC.x, TC.y, TC.expect);
accumulate &= test0<S1, U2, Output>(-TC.x, TC.y, TC.expect);
accumulate &= test0<U2, S1, Output>(TC.x, -TC.y, TC.expect);
}
{ // Test with mixed signs
using Output = std::common_type_t<S2, U1>;
accumulate &= test0<S2, U1, Output>(TC.x, TC.y, TC.expect);
accumulate &= test0<U1, S2, Output>(TC.x, TC.y, TC.expect);
accumulate &= test0<S2, U1, Output>(-TC.x, TC.y, TC.expect);
accumulate &= test0<U1, S2, Output>(TC.x, -TC.y, TC.expect);
}
}
return accumulate;
}
int main(int, char**)
{
auto non_cce = std::rand(); // a value that can't possibly be constexpr
static_assert(do_test<signed char>(), "");
static_assert(do_test<short>(), "");
static_assert(do_test<int>(), "");
static_assert(do_test<long>(), "");
static_assert(do_test<long long>(), "");
assert(do_test<signed char>(non_cce));
assert(do_test<short>(non_cce));
assert(do_test<int>(non_cce));
assert(do_test<long>(non_cce));
assert(do_test<long long>(non_cce));
static_assert(do_test<std::int8_t>(), "");
static_assert(do_test<std::int16_t>(), "");
static_assert(do_test<std::int32_t>(), "");
static_assert(do_test<std::int64_t>(), "");
assert(do_test<std::int8_t>(non_cce));
assert(do_test<std::int16_t>(non_cce));
assert(do_test<std::int32_t>(non_cce));
assert(do_test<std::int64_t>(non_cce));
static_assert(do_test<signed char, int>(), "");
static_assert(do_test<int, signed char>(), "");
static_assert(do_test<short, int>(), "");
static_assert(do_test<int, short>(), "");
static_assert(do_test<int, long>(), "");
static_assert(do_test<long, int>(), "");
static_assert(do_test<int, long long>(), "");
static_assert(do_test<long long, int>(), "");
assert((do_test<signed char, int>(non_cce)));
assert((do_test<int, signed char>(non_cce)));
assert((do_test<short, int>(non_cce)));
assert((do_test<int, short>(non_cce)));
assert((do_test<int, long>(non_cce)));
assert((do_test<long, int>(non_cce)));
assert((do_test<int, long long>(non_cce)));
assert((do_test<long long, int>(non_cce)));
// LWG#2837
{
auto res1 = std::lcm(static_cast<std::int64_t>(1234), INT32_MIN);
TEST_IGNORE_NODISCARD std::lcm(INT_MIN, 2UL); // this used to trigger UBSAN
static_assert(std::is_same_v<decltype(res1), std::int64_t>, "");
assert(res1 == 1324997410816LL);
}
return 0;
}