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 Engine, size_t w, class UIntType>
13 // class independent_bits_engine
14
15 // result_type operator()();
16
17 #include <random>
18 #include <cassert>
19
20 #include "test_macros.h"
21
22 template <class UIntType, UIntType Min, UIntType Max>
23 class rand1
24 {
25 public:
26 // types
27 typedef UIntType result_type;
28
29 private:
30 result_type x_;
31
32 static_assert(Min < Max, "rand1 invalid parameters");
33 public:
34
35 #if TEST_STD_VER < 11 && defined(_LIBCPP_VERSION)
36 // Workaround for lack of constexpr in C++03
37 static const result_type _Min = Min;
38 static const result_type _Max = Max;
39 #endif
40
min()41 static TEST_CONSTEXPR result_type min() {return Min;}
max()42 static TEST_CONSTEXPR result_type max() {return Max;}
43
rand1(result_type sd=Min)44 explicit rand1(result_type sd = Min) : x_(sd)
45 {
46 if (x_ > Max)
47 x_ = Max;
48 }
49
operator ()()50 result_type operator()()
51 {
52 result_type r = x_;
53 if (x_ < Max)
54 ++x_;
55 else
56 x_ = Min;
57 return r;
58 }
59 };
60
61 void
test1()62 test1()
63 {
64 typedef std::independent_bits_engine<rand1<unsigned, 0, 10>, 16, unsigned> E;
65
66 E e;
67 assert(e() == 6958);
68 }
69
70 void
test2()71 test2()
72 {
73 typedef std::independent_bits_engine<rand1<unsigned, 0, 100>, 16, unsigned> E;
74
75 E e;
76 assert(e() == 66);
77 }
78
79 void
test3()80 test3()
81 {
82 typedef std::independent_bits_engine<rand1<unsigned, 0, 0xFFFFFFFF>, 32, unsigned> E;
83
84 E e(5);
85 assert(e() == 5);
86 }
87
88 void
test4()89 test4()
90 {
91 typedef std::independent_bits_engine<rand1<unsigned, 0, 0xFFFFFFFF>, 7, unsigned> E;
92
93 E e(129);
94 assert(e() == 1);
95 }
96
97 void
test5()98 test5()
99 {
100 typedef std::independent_bits_engine<rand1<unsigned, 2, 3>, 1, unsigned> E;
101
102 E e(6);
103 assert(e() == 1);
104 }
105
106 void
test6()107 test6()
108 {
109 typedef std::independent_bits_engine<rand1<unsigned, 2, 3>, 11, unsigned> E;
110
111 E e(6);
112 assert(e() == 1365);
113 }
114
115 void
test7()116 test7()
117 {
118 typedef std::independent_bits_engine<rand1<unsigned, 2, 3>, 32, unsigned> E;
119
120 E e(6);
121 assert(e() == 2863311530u);
122 }
123
124 void
test8()125 test8()
126 {
127 typedef std::independent_bits_engine<std::mt19937, 64, unsigned long long> E;
128
129 E e(6);
130 assert(e() == 16470362623952407241ull);
131 }
132
main()133 int main()
134 {
135 test1();
136 test2();
137 test3();
138 test4();
139 test5();
140 test6();
141 test7();
142 test8();
143 }
144