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 // test unsigned long to_ulong() const;
11
12 #include <bitset>
13 #include <algorithm>
14 #include <type_traits>
15 #include <limits>
16 #include <climits>
17 #include <cassert>
18
19 template <std::size_t N>
test_to_ulong()20 void test_to_ulong()
21 {
22 const std::size_t M = sizeof(unsigned long) * CHAR_BIT < N ? sizeof(unsigned long) * CHAR_BIT : N;
23 const bool is_M_zero = std::integral_constant<bool, M == 0>::value; // avoid compiler warnings
24 const std::size_t X = is_M_zero ? sizeof(unsigned long) * CHAR_BIT - 1 : sizeof(unsigned long) * CHAR_BIT - M;
25 const std::size_t max = is_M_zero ? 0 : std::size_t(std::numeric_limits<unsigned long>::max()) >> X;
26 std::size_t tests[] = {0,
27 std::min<std::size_t>(1, max),
28 std::min<std::size_t>(2, max),
29 std::min<std::size_t>(3, max),
30 std::min(max, max-3),
31 std::min(max, max-2),
32 std::min(max, max-1),
33 max};
34 for (std::size_t i = 0; i < sizeof(tests)/sizeof(tests[0]); ++i)
35 {
36 std::size_t j = tests[i];
37 std::bitset<N> v(j);
38 assert(j == v.to_ulong());
39 }
40
41 { // test values bigger than can fit into the bitset
42 const unsigned long val = 0x5AFFFFA5UL;
43 const bool canFit = N < sizeof(unsigned long) * CHAR_BIT;
44 const unsigned long mask = canFit ? (1UL << (canFit ? N : 0)) - 1 : (unsigned long)(-1); // avoid compiler warnings
45 std::bitset<N> v(val);
46 assert(v.to_ulong() == (val & mask)); // we shouldn't return bit patterns from outside the limits of the bitset.
47 }
48 }
49
main()50 int main()
51 {
52 test_to_ulong<0>();
53 test_to_ulong<1>();
54 test_to_ulong<31>();
55 test_to_ulong<32>();
56 test_to_ulong<33>();
57 test_to_ulong<63>();
58 test_to_ulong<64>();
59 test_to_ulong<65>();
60 test_to_ulong<1000>();
61 }
62