test.pass.cpp

//===----------------------------------------------------------------------===//
//
//                     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.
//
//===----------------------------------------------------------------------===//

// <algorithm>

// template <typename _Tp> _Tp __half_as_unsigned(const _Tp&);

// __half_as_unsigned divide integer number by 2 as unsigned number
// if it's safe to do so. It can be an important optimization for lower bound,
// for example.

#include <algorithm>
#include <cassert>
#include <limits>
#include <type_traits>

#include "test_macros.h"
#include "user_defined_integral.hpp"


template <class IntType, class LimitType = IntType>
TEST_CONSTEXPR bool test(IntType max_v = std::numeric_limits<LimitType>::max()) {
    return std::__half_positive(max_v) == max_v / 2;
}

int main()
{
    {
        assert(test<char>());
        assert(test<int>());
        assert(test<long>());
        assert(test<size_t>());
        assert((test<UserDefinedIntegral<int>, int>()));
#if !defined(_LIBCPP_HAS_NO_INT128)
        assert(test<__int128_t>());
#endif
    }
#if TEST_STD_VER >= 11
    {
        static_assert(test<char>(), "");
        static_assert(test<int>(), "");
        static_assert(test<long>(), "");
        static_assert(test<size_t>(), "");
#if !defined(_LIBCPP_HAS_NO_INT128)
        static_assert(test<__int128_t>(), "");
#endif
    }
#endif // TEST_STD_VER >= 11
}