libcxx/test/std/numerics/complex.number/complex.ops/complex_times_complex.pass.cpp

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// <complex>

// template<class T>
//   complex<T>
//   operator*(const complex<T>& lhs, const complex<T>& rhs); // constexpr in C++20

// ADDITIONAL_COMPILE_FLAGS(has-fconstexpr-steps): -fconstexpr-steps=2000000

#include <complex>
#include <cassert>

#include "test_macros.h"
#include "../cases.h"

template <class T>
TEST_CONSTEXPR_CXX20
bool
test()
{
    const std::complex<T> lhs(1.5, 2.5);
    const std::complex<T> rhs(1.5, 2.5);
    assert(lhs * rhs == std::complex<T>(-4.0, 7.5));
    return true;
}

// test edges

TEST_CONSTEXPR_CXX20 bool test_edges()
{
    const unsigned N = sizeof(testcases) / sizeof(testcases[0]);
    int classification[N];
    for (unsigned i=0; i < N; ++i)
        classification[i] = classify(testcases[i]);

    for (unsigned i = 0; i < N; ++i)
    {
        for (unsigned j = 0; j < N; ++j)
        {
            std::complex<double> r = testcases[i] * testcases[j];
            switch (classification[i])
            {
            case zero:
                switch (classification[j])
                {
                case zero:
                case non_zero:
                    assert(classify(r) == zero);
                    break;
                case inf:
                case NaN:
                case non_zero_nan:
                    assert(classify(r) == NaN);
                    break;
                }
                break;
            case non_zero:
                switch (classification[j])
                {
                case zero:
                    assert(classify(r) == zero);
                    break;
                case non_zero:
                    assert(classify(r) == non_zero);
                    break;
                case inf:
                    assert(classify(r) == inf);
                    break;
                case NaN:
                case non_zero_nan:
                    assert(classify(r) == NaN);
                    break;
                }
                break;
            case inf:
                switch (classification[j])
                {
                case zero:
                case NaN:
                    assert(classify(r) == NaN);
                    break;
                case non_zero:
                case inf:
                case non_zero_nan:
                    assert(classify(r) == inf);
                    break;
                }
                break;
            case NaN:
                assert(classify(r) == NaN);
                break;
            case non_zero_nan:
                switch (classification[j])
                {
                case inf:
                    assert(classify(r) == inf);
                    break;
                case zero:
                case non_zero:
                case NaN:
                case non_zero_nan:
                    assert(classify(r) == NaN);
                    break;
                }
                break;
            }
        }
    }
    return true;
}

int main(int, char**)
{
    test<float>();
    test<double>();
    test<long double>();
    test_edges();

#if TEST_STD_VER > 17
    static_assert(test<float>());
    static_assert(test<double>());
    static_assert(test<long double>());
    static_assert(test_edges());
#endif

  return 0;
}