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 long to_ullong() const; 11 12 #include <bitset> 13 #include <algorithm> 14 #include <type_traits> 15 #include <climits> 16 #include <cassert> 17 18 template <std::size_t N> 19 void test_to_ullong() 20 { 21 const std::size_t M = sizeof(unsigned long long) * CHAR_BIT < N ? sizeof(unsigned long long) * CHAR_BIT : N; 22 const bool is_M_zero = std::integral_constant<bool, M == 0>::value; // avoid compiler warnings 23 const std::size_t X = is_M_zero ? sizeof(unsigned long long) * CHAR_BIT - 1 : sizeof(unsigned long long) * CHAR_BIT - M; 24 const unsigned long long max = is_M_zero ? 0 : (unsigned long long)(-1) >> X; 25 unsigned long long tests[] = {0, 26 std::min<unsigned long long>(1, max), 27 std::min<unsigned long long>(2, max), 28 std::min<unsigned long long>(3, max), 29 std::min(max, max-3), 30 std::min(max, max-2), 31 std::min(max, max-1), 32 max}; 33 for (std::size_t i = 0; i < sizeof(tests)/sizeof(tests[0]); ++i) 34 { 35 unsigned long long j = tests[i]; 36 std::bitset<N> v(j); 37 assert(j == v.to_ullong()); 38 } 39 { // test values bigger than can fit into the bitset 40 const unsigned long long val = 0x55AAAAFFFFAAAA55ULL; 41 const bool canFit = N < sizeof(unsigned long long) * CHAR_BIT; 42 const unsigned long long mask = canFit ? (1ULL << (canFit ? N : 0)) - 1 : (unsigned long long)(-1); // avoid compiler warnings 43 std::bitset<N> v(val); 44 assert(v.to_ullong() == (val & mask)); // we shouldn't return bit patterns from outside the limits of the bitset. 45 } 46 } 47 48 int main() 49 { 50 // test_to_ullong<0>(); 51 test_to_ullong<1>(); 52 test_to_ullong<31>(); 53 test_to_ullong<32>(); 54 test_to_ullong<33>(); 55 test_to_ullong<63>(); 56 test_to_ullong<64>(); 57 test_to_ullong<65>(); 58 test_to_ullong<1000>(); 59 } 60
