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> 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 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
