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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// test unsigned long to_ulong() const;
#include <bitset>
#include <algorithm>
#include <type_traits>
#include <limits>
#include <climits>
#include <cassert>
#include <iostream>
template <std::size_t N>
void test_to_ulong()
{
std::cout << "Testing size = " << N << std::endl;
const std::size_t M = sizeof(unsigned long) * CHAR_BIT < N ? sizeof(unsigned long) * CHAR_BIT : N;
const bool is_M_zero = std::integral_constant<bool, M == 0>::value; // avoid compiler warnings
const std::size_t X = is_M_zero ? sizeof(unsigned long) * CHAR_BIT - 1 : sizeof(unsigned long) * CHAR_BIT - M;
const std::size_t max = is_M_zero ? 0 : std::size_t(std::numeric_limits<unsigned long>::max()) >> X;
std::size_t tests[] = {0,
std::min<std::size_t>(1, max),
std::min<std::size_t>(2, max),
std::min<std::size_t>(3, max),
std::min(max, max-3),
std::min(max, max-2),
std::min(max, max-1),
max};
for (std::size_t i = 0; i < sizeof(tests)/sizeof(tests[0]); ++i)
{
std::size_t j = tests[i];
std::cout << " Testing value = " << j << std::endl;
std::bitset<N> v(j);
assert(j == v.to_ulong());
}
{ // test values bigger than can fit into the bitset
const unsigned long val = 0xAAAAAAAAULL;
const bool canFit = N < sizeof(unsigned long) * CHAR_BIT;
const unsigned long mask = canFit ? (1ULL << N) - 1 : (unsigned long)(-1);
std::bitset<N> v(val);
assert(v.to_ulong() == (val & mask)); // we shouldn't return bit patterns from outside the limits of the bitset.
}
}
int main()
{
test_to_ulong<0>();
test_to_ulong<1>();
test_to_ulong<31>();
test_to_ulong<32>();
test_to_ulong<33>();
test_to_ulong<63>();
test_to_ulong<64>();
test_to_ulong<65>();
test_to_ulong<1000>();
}
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