1 //===----------------------------------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // <random>
11 
12 // template <class UIntType, UIntType a, UIntType c, UIntType m>
13 // class linear_congruential_engine
14 // {
15 // public:
16 //     engine characteristics
17 //     static constexpr result_type multiplier = a;
18 //     static constexpr result_type increment = c;
19 //     static constexpr result_type modulus = m;
20 //     static constexpr result_type min() { return c == 0u ? 1u: 0u;}
21 //     static constexpr result_type max() { return m - 1u;}
22 //     static constexpr result_type default_seed = 1u;
23 
24 #include <random>
25 #include <type_traits>
26 #include <cassert>
27 
28 #include "test_macros.h"
29 
30 template <class T>
where(const T &)31 void where(const T &) {}
32 
33 template <class T, T a, T c, T m>
34 void
test1()35 test1()
36 {
37     typedef std::linear_congruential_engine<T, a, c, m> LCE;
38     typedef typename LCE::result_type result_type;
39     static_assert((LCE::multiplier == a), "");
40     static_assert((LCE::increment == c), "");
41     static_assert((LCE::modulus == m), "");
42 #if TEST_STD_VER >= 11
43     static_assert((LCE::min() == (c == 0u ? 1u: 0u)), "");
44 #else
45     assert((LCE::min() == (c == 0u ? 1u: 0u)));
46 #endif
47 
48 #ifdef TEST_COMPILER_C1XX
49     #pragma warning(push)
50     #pragma warning(disable: 4310) // cast truncates constant value
51 #endif // TEST_COMPILER_C1XX
52 
53 #if TEST_STD_VER >= 11
54     static_assert((LCE::max() == result_type(m - 1u)), "");
55 #else
56     assert((LCE::max() == result_type(m - 1u)));
57 #endif
58 
59 #ifdef TEST_COMPILER_C1XX
60     #pragma warning(pop)
61 #endif // TEST_COMPILER_C1XX
62 
63     static_assert((LCE::default_seed == 1), "");
64     where(LCE::multiplier);
65     where(LCE::increment);
66     where(LCE::modulus);
67     where(LCE::default_seed);
68 }
69 
70 template <class T>
71 void
test()72 test()
73 {
74     test1<T, 0, 0, 0>();
75     test1<T, 0, 1, 2>();
76     test1<T, 1, 1, 2>();
77     const T M(static_cast<T>(-1));
78     test1<T, 0, 0, M>();
79     test1<T, 0, M-2, M>();
80     test1<T, 0, M-1, M>();
81     test1<T, M-2, 0, M>();
82     test1<T, M-2, M-2, M>();
83     test1<T, M-2, M-1, M>();
84     test1<T, M-1, 0, M>();
85     test1<T, M-1, M-2, M>();
86     test1<T, M-1, M-1, M>();
87 }
88 
main()89 int main()
90 {
91     test<unsigned short>();
92     test<unsigned int>();
93     test<unsigned long>();
94     test<unsigned long long>();
95 }
96