// Copyright (C) 2021 The Qt Company Ltd.
// Copyright (C) 2016 by Southwest Research Institute (R)
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only

#include <QTest>
#include <QFloat16>
#include <QMetaType>
#include <QTextStream>

#include <private/qcomparisontesthelper_p.h>

#include <math.h>

//#define DO_FULL_TEST

static_assert(sizeof(float) == sizeof(quint32), "Float not 32-bit");

class tst_qfloat16: public QObject
{
    Q_OBJECT

private slots:
    void compareCompiles();
    void relationalOperatorsAreConstexpr();
    void ordering_data();
    void ordering();
    void fuzzyCompare_data();
    void fuzzyCompare();
    void fuzzyIsNull_data();
    void fuzzyIsNull();
    void ltgt_data();
    void ltgt();
    void qNaN();
    void infinity();
    void float_cast();
    void float_cast_data();
    void promotionTests();
    void arithOps_data();
    void arithOps();
#if defined DO_FULL_TEST
    void floatToFloat16Full_data();
    void floatToFloat16Full();
    void floatFromFloat16Full();
#endif
    void floatToFloat16();
    void floatFromFloat16();
    void finite_data();
    void finite();
    void properties();
    void limits();
    void mantissaOverflow();
    void dataStream();
    void textStream();
};

void tst_qfloat16::compareCompiles()
{
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, float>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, double>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, long double>();
#if QFLOAT16_IS_NATIVE
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, qfloat16::NativeType>();
#endif
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, int>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, qint8>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, quint8>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, qint16>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, quint16>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, char16_t>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, long>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, unsigned long>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, wchar_t>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, qint32>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, quint32>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, qint64>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, quint64>();
#ifdef QT_SUPPORTS_INT128
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, qint128>();
    QTestPrivate::testAllComparisonOperatorsCompile<qfloat16, quint128>();
#endif
}

void tst_qfloat16::relationalOperatorsAreConstexpr()
{
#if QFLOAT16_IS_NATIVE

#define CHECK_CONSTEXPR(Type) \
    do { \
        constexpr qfloat16 lhs = qfloat16(0.0f); \
        constexpr Type rhs = 1; \
        static_assert(lhs < rhs); \
        static_assert(rhs >= lhs); \
    } while (false)

    CHECK_CONSTEXPR(qfloat16);
    CHECK_CONSTEXPR(float);
    CHECK_CONSTEXPR(double);
    CHECK_CONSTEXPR(long double);
    CHECK_CONSTEXPR(qfloat16::NativeType);
    CHECK_CONSTEXPR(qint8);
    CHECK_CONSTEXPR(quint8);
    CHECK_CONSTEXPR(qint16);
    CHECK_CONSTEXPR(quint16);
    CHECK_CONSTEXPR(qint32);
    CHECK_CONSTEXPR(quint32);
    CHECK_CONSTEXPR(long);
    CHECK_CONSTEXPR(unsigned long);
    CHECK_CONSTEXPR(qint64);
    CHECK_CONSTEXPR(quint64);
#ifdef QT_SUPPORTS_INT128
    CHECK_CONSTEXPR(qint128);
    CHECK_CONSTEXPR(quint128);
#endif

#undef CHECK_CONSTEXPR

#else
    QSKIP("This check is only relevant for native float16 types");
#endif // QFLOAT16_IS_NATIVE
}

void tst_qfloat16::ordering_data()
{
    QTest::addColumn<float>("left");
    QTest::addColumn<float>("right");

    auto row = [](float left, float right) {
        QTest::addRow("%f_vs_%f", left, right) << left << right;
    };

    row(0.0f, 0.0f);
    row(0.000001f, 0.0f);
    row(0.0f, 0.000001f);
    row(-1.000001f, 1.000001f);
    const float nan = std::numeric_limits<float>::quiet_NaN();
    const float inf = std::numeric_limits<float>::infinity();
    row(nan, nan);
    row(nan, inf);
    row(inf, nan);
    row(-inf, nan);
    row(nan, -inf);
    row(-inf, inf);
    row(inf, -inf);
    row(-inf, 0.0f);
    row(0.0f, inf);
    row(0.0f, nan);
    row(nan, 0.0f);
    row(2.0f, 314.159f);
    row(-314.159f, 2.0f);
    row(-2.0f, 314.159f);
    row(nan, 314.159f);
    row(-314.159f, inf);
    row(-inf, 314.159f);
    row(2.0f, -inf);
    row(-2.0f, nan);
    row(-inf, -2.0f);
    // testing with values outside qfloat16 range
    row(0.0f, 13e5f);
    // generateRow(inf, 13e5f); // fails qfloat16 vs qfloat16 and qfloat16 vs int (QTBUG-118193)
    row(0.0f, -13e5f);
    // generateRow(-inf, -13e5f); // fails qfloat16 vs qfloat16 and qfloat16 vs int (QTBUG-118193)
}

void tst_qfloat16::ordering()
{
    QFETCH(float, left);
    QFETCH(float, right);

    const auto expectedOrder = Qt::compareThreeWay(left, right);
    const auto lhs = qfloat16(left);

#define POSTCHECK(msg) \
    if (QTest::currentTestFailed()) { qDebug(msg); return; }

#define CHECK_FP(RHS) \
    do { \
        QTestPrivate::testAllComparisonOperators(lhs, static_cast<RHS>(right), expectedOrder); \
        POSTCHECK("qfloat16 vs " #RHS " comparison failed") \
    } while (false) \
    /* END */

    CHECK_FP(qfloat16);
    CHECK_FP(float);
    CHECK_FP(double);
    CHECK_FP(long double);

#undef CHECK_FP

#define CHECK_INT(RHS) \
    do { \
        const auto rhs = static_cast<RHS>(right); \
        const auto expectedRes = Qt::compareThreeWay(left, rhs); \
        QTestPrivate::testAllComparisonOperators(lhs, rhs, expectedRes); \
        POSTCHECK("qfloat16 vs " #RHS " comparison failed") \
    } while (false) \
    /* END */

    if (qIsFinite(right)) {
        CHECK_INT(int);
        CHECK_INT(qint8);
        CHECK_INT(signed char);
        CHECK_INT(qint16);
        CHECK_INT(qint32);
        CHECK_INT(qint64);
#if QT_SUPPORTS_INT128
        CHECK_INT(qint128);
#endif
        if (right >= 0) {
            CHECK_INT(unsigned int);
            CHECK_INT(quint8);
            CHECK_INT(unsigned char);
            CHECK_INT(quint16);
            CHECK_INT(quint32);
            CHECK_INT(quint64);
    #if QT_SUPPORTS_INT128
            CHECK_INT(quint128);
    #endif
        }
    }

#undef CHECK_INT
#undef POSTCHECK
}

void tst_qfloat16::fuzzyCompare_data()
{
    QTest::addColumn<qfloat16>("val1");
    QTest::addColumn<qfloat16>("val2");
    QTest::addColumn<bool>("fuzEqual");
    QTest::addColumn<bool>("isEqual");

    QTest::newRow("zero")  << qfloat16(0.0f)   << qfloat16(0.0f)   << true << true;
    QTest::newRow("ten")   << qfloat16(1e1f)   << qfloat16(1e1f)   << true << true;
    QTest::newRow("large") << qfloat16(1e4f)   << qfloat16(1e4f)   << true << true;
    QTest::newRow("small") << qfloat16(1e-5f)  << qfloat16(1e-5f)  << true << true;
    QTest::newRow("eps")   << qfloat16(10.01f) << qfloat16(10.02f) << true << false;
    QTest::newRow("eps2")  << qfloat16(1024.f) << qfloat16(1033.f) << true << false;

    QTest::newRow("mis1") << qfloat16(0.0f)   << qfloat16(1.0f)   << false << false;
    QTest::newRow("mis2") << qfloat16(0.0f)   << qfloat16(1e7f)   << false << false;
    QTest::newRow("mis3") << qfloat16(0.0f)   << qfloat16(1e-4f)  << false << false;
    QTest::newRow("mis4") << qfloat16(1e8f)   << qfloat16(1e-8f)  << false << false;
    QTest::newRow("mis5") << qfloat16(1e-4f)  << qfloat16(1e-5)   << false << false;
    QTest::newRow("mis6") << qfloat16(1024.f) << qfloat16(1034.f) << false << false;
}

void tst_qfloat16::fuzzyCompare()
{
    QFETCH(qfloat16, val1);
    QFETCH(qfloat16, val2);
    QFETCH(bool, fuzEqual);
    QFETCH(bool, isEqual);

    if (!isEqual && (val1==val2))
        qWarning() << "Identical arguments provided unintentionally!";

    if (fuzEqual) {
        QVERIFY(::qFuzzyCompare(val1, val2));
        QVERIFY(::qFuzzyCompare(val2, val1));
        QVERIFY(::qFuzzyCompare(-val1, -val2));
        QVERIFY(::qFuzzyCompare(-val2, -val1));
    } else {
        QVERIFY(!::qFuzzyCompare(val1, val2));
        QVERIFY(!::qFuzzyCompare(val2, val1));
        QVERIFY(!::qFuzzyCompare(-val1, -val2));
        QVERIFY(!::qFuzzyCompare(-val2, -val1));
    }
}

void tst_qfloat16::fuzzyIsNull_data()
{
    QTest::addColumn<qfloat16>("value");
    QTest::addColumn<bool>("isNull");
    using Bounds = std::numeric_limits<qfloat16>;
    const qfloat16 one(1), huge(1000), tiny(0.00976f);

    QTest::newRow("zero") << qfloat16(0.0f) << true;
    QTest::newRow("min") << Bounds::min() << true;
    QTest::newRow("denorm_min") << Bounds::denorm_min() << true;
    QTest::newRow("tiny") << tiny << true;

    QTest::newRow("deci") << qfloat16(.1) << false;
    QTest::newRow("one") << one << false;
    QTest::newRow("ten") << qfloat16(10) << false;
    QTest::newRow("huge") << huge << false;
}

void tst_qfloat16::fuzzyIsNull()
{
    QFETCH(qfloat16, value);
    QFETCH(bool, isNull);

    QCOMPARE(::qFuzzyIsNull(value), isNull);
    QCOMPARE(::qFuzzyIsNull(-value), isNull);
}

void tst_qfloat16::ltgt_data()
{
    QTest::addColumn<float>("val1");
    QTest::addColumn<float>("val2");

    QTest::newRow("zero")  << 0.0f << 0.0f;
    QTest::newRow("-zero") << -0.0f << 0.0f;
    QTest::newRow("ten")   << 10.0f << 10.0f;
    QTest::newRow("large") << 100000.0f << 100000.0f;
    QTest::newRow("small") << 0.0000001f << 0.0000001f;
    QTest::newRow("eps")   << 10.000000000000001f << 10.00000000000002f;
    QTest::newRow("eps2")  << 10.000000000000001f << 10.000000000000009f;

    QTest::newRow("mis1") << 0.0f << 1.0f;
    QTest::newRow("mis2") << 0.0f << 10000000.0f;
    QTest::newRow("mis3") << 0.0f << 0.0001f;
    QTest::newRow("mis4") << 100000000.0f << 0.000000001f;
    QTest::newRow("mis5") << 0.0001f << 0.00001f;

    QTest::newRow("45,23") << 45.f << 23.f;
    QTest::newRow("1000,76") << 1000.f << 76.f;
}

void tst_qfloat16::ltgt()
{
    QFETCH(float, val1);
    QFETCH(float, val2);

    QCOMPARE(qfloat16(val1)  == qfloat16(val2),   val1 ==  val2);
    QCOMPARE(qfloat16(val1)  <  qfloat16(val2),   val1 <   val2);
    QCOMPARE(qfloat16(val1)  <= qfloat16(val2),   val1 <=  val2);
    QCOMPARE(qfloat16(val1)  >  qfloat16(val2),   val1 >   val2);
    QCOMPARE(qfloat16(val1)  >= qfloat16(val2),   val1 >=  val2);

    QCOMPARE(qfloat16(val1)  == qfloat16(-val2),  val1 == -val2);
    QCOMPARE(qfloat16(val1)  <  qfloat16(-val2),  val1 <  -val2);
    QCOMPARE(qfloat16(val1)  <= qfloat16(-val2),  val1 <= -val2);
    QCOMPARE(qfloat16(val1)  >  qfloat16(-val2),  val1 >  -val2);
    QCOMPARE(qfloat16(val1)  >= qfloat16(-val2),  val1 >= -val2);

    QCOMPARE(qfloat16(-val1) == qfloat16(val2),  -val1 ==  val2);
    QCOMPARE(qfloat16(-val1) <  qfloat16(val2),  -val1 <   val2);
    QCOMPARE(qfloat16(-val1) <= qfloat16(val2),  -val1 <=  val2);
    QCOMPARE(qfloat16(-val1) >  qfloat16(val2),  -val1 >   val2);
    QCOMPARE(qfloat16(-val1) >= qfloat16(val2),  -val1 >=  val2);

    QCOMPARE(qfloat16(-val1) == qfloat16(-val2), -val1 == -val2);
    QCOMPARE(qfloat16(-val1) <  qfloat16(-val2), -val1 <  -val2);
    QCOMPARE(qfloat16(-val1) <= qfloat16(-val2), -val1 <= -val2);
    QCOMPARE(qfloat16(-val1) >  qfloat16(-val2), -val1 >  -val2);
    QCOMPARE(qfloat16(-val1) >= qfloat16(-val2), -val1 >= -val2);
}

#if defined __FAST_MATH__ && (__GNUC__ * 100 + __GNUC_MINOR__ >= 404)
   // turn -ffast-math off
#  pragma GCC optimize "no-fast-math"
#endif

void tst_qfloat16::qNaN()
{
#if defined __FAST_MATH__ && (__GNUC__ * 100 + __GNUC_MINOR__ < 404)
    QSKIP("Non-conformant fast math mode is enabled, cannot run test");
#endif
    using Bounds = std::numeric_limits<qfloat16>;
    const qfloat16 nan = Bounds::quiet_NaN();
    const qfloat16 zero(0), one(1);
    QVERIFY(!(zero > nan));
    QVERIFY(!(zero < nan));
    QVERIFY(!(zero == nan));
    QVERIFY(!qIsInf(nan));
    QVERIFY(qIsNaN(nan));
    QVERIFY(qIsNaN(nan + one));
    QVERIFY(qIsNaN(-nan));
    QVERIFY(qIsNaN(nan * zero));
    QVERIFY(qIsNaN(Bounds::infinity() * zero));

    QVERIFY(!nan.isNormal());
    QVERIFY(!qIsFinite(nan));
    QVERIFY(!(nan == nan));
    QCOMPARE(nan, nan); // Despite the preceding
    QCOMPARE(qFpClassify(nan), FP_NAN);
}

void tst_qfloat16::infinity()
{
    const qfloat16 huge = std::numeric_limits<qfloat16>::infinity();
    const qfloat16 zero(0), one(1), two(2);
    QVERIFY(huge > -huge);
    QVERIFY(huge > zero);
    QVERIFY(-huge < zero);
    QCOMPARE(huge, huge);
    QCOMPARE(-huge, -huge);

    QCOMPARE(one / huge, zero);
    QVERIFY(qFuzzyCompare(one / huge, zero)); // (same thing)

    QVERIFY(qIsInf(huge));
    QVERIFY(qIsInf(-huge));
    QVERIFY(qIsInf(two * huge));
    QVERIFY(qIsInf(huge * two));

    QVERIFY(!huge.isNormal());
    QVERIFY(!(-huge).isNormal());
    QVERIFY(!qIsNaN(huge));
    QVERIFY(!qIsNaN(-huge));
    QVERIFY(!qIsFinite(huge));
    QVERIFY(!qIsFinite(-huge));
    QCOMPARE(qFpClassify(huge), FP_INFINITE);
    QCOMPARE(qFpClassify(-huge), FP_INFINITE);
}

void tst_qfloat16::float_cast_data()
{
    QTest::addColumn<float>("val");

    QTest::newRow("zero")  << 0.f;
    QTest::newRow("one")   << 1e0f;
    QTest::newRow("ten")   << 1e1f;
    QTest::newRow("hund")  << 1e2f;
    QTest::newRow("thou")  << 1e3f;
    QTest::newRow("tthou") << 1e4f;
    //QTest::newRow("hthou") << 1e5f;
    //QTest::newRow("mil")   << 1e6f;
    //QTest::newRow("tmil")  << 1e7f;
    //QTest::newRow("hmil")  << 1e8f;
}

void tst_qfloat16::float_cast()
{
    QFETCH(float, val);

    QVERIFY(qFuzzyCompare((float)(qfloat16(val)),val));
    QVERIFY(qFuzzyCompare((float)(qfloat16(-val)),-val));
    QVERIFY(qFuzzyCompare((double)(qfloat16(val)),(double)(val)));
    QVERIFY(qFuzzyCompare((double)(qfloat16(-val)),(double)(-val)));
    //QVERIFY(qFuzzyCompare((long double)(qfloat16(val)),(long double)(val)));
    //QVERIFY(qFuzzyCompare((long double)(qfloat16(-val)),(long double)(-val)));
}

void tst_qfloat16::promotionTests()
{
    QCOMPARE(sizeof(qfloat16),sizeof(qfloat16(1.f)+qfloat16(1.f)));
    QCOMPARE(sizeof(qfloat16),sizeof(qfloat16(1.f)-qfloat16(1.f)));
    QCOMPARE(sizeof(qfloat16),sizeof(qfloat16(1.f)*qfloat16(1.f)));
    QCOMPARE(sizeof(qfloat16),sizeof(qfloat16(1.f)/qfloat16(1.f)));

    QCOMPARE(sizeof(float),sizeof(1.f+qfloat16(1.f)));
    QCOMPARE(sizeof(float),sizeof(1.f-qfloat16(1.f)));
    QCOMPARE(sizeof(float),sizeof(1.f*qfloat16(1.f)));
    QCOMPARE(sizeof(float),sizeof(1.f/qfloat16(1.f)));

    QCOMPARE(sizeof(float),sizeof(qfloat16(1.f)+1.f));
    QCOMPARE(sizeof(float),sizeof(qfloat16(1.f)-1.f));
    QCOMPARE(sizeof(float),sizeof(qfloat16(1.f)*1.f));
    QCOMPARE(sizeof(float),sizeof(qfloat16(1.f)/1.f));

    QCOMPARE(sizeof(double),sizeof(1.+qfloat16(1.f)));
    QCOMPARE(sizeof(double),sizeof(1.-qfloat16(1.f)));
    QCOMPARE(sizeof(double),sizeof(1.*qfloat16(1.f)));
    QCOMPARE(sizeof(double),sizeof(1./qfloat16(1.f)));

    QCOMPARE(sizeof(double),sizeof(qfloat16(1.f)+1.));
    QCOMPARE(sizeof(double),sizeof(qfloat16(1.f)-1.));
    QCOMPARE(sizeof(double),sizeof(qfloat16(1.f)*1.));
    QCOMPARE(sizeof(double),sizeof(qfloat16(1.f)/1.));

    QCOMPARE(sizeof(long double),sizeof((long double)(1.)+qfloat16(1.f)));
    QCOMPARE(sizeof(long double),sizeof((long double)(1.)-qfloat16(1.f)));
    QCOMPARE(sizeof(long double),sizeof((long double)(1.)*qfloat16(1.f)));
    QCOMPARE(sizeof(long double),sizeof((long double)(1.)/qfloat16(1.f)));

    QCOMPARE(sizeof(long double),sizeof(qfloat16(1.f)+(long double)(1.)));
    QCOMPARE(sizeof(long double),sizeof(qfloat16(1.f)-(long double)(1.)));
    QCOMPARE(sizeof(long double),sizeof(qfloat16(1.f)*(long double)(1.)));
    QCOMPARE(sizeof(long double),sizeof(qfloat16(1.f)/(long double)(1.)));

    QCOMPARE(sizeof(double),sizeof(1+qfloat16(1.f)));
    QCOMPARE(sizeof(double),sizeof(1-qfloat16(1.f)));
    QCOMPARE(sizeof(double),sizeof(1*qfloat16(1.f)));
    QCOMPARE(sizeof(double),sizeof(1/qfloat16(1.f)));

    QCOMPARE(sizeof(double),sizeof(qfloat16(1.f)+1));
    QCOMPARE(sizeof(double),sizeof(qfloat16(1.f)-1));
    QCOMPARE(sizeof(double),sizeof(qfloat16(1.f)*1));
    QCOMPARE(sizeof(double),sizeof(qfloat16(1.f)/1));

    QCOMPARE(QString::number(1.f),QString::number(double(qfloat16(1.f))));
}

void tst_qfloat16::arithOps_data()
{
    QTest::addColumn<float>("val1");
    QTest::addColumn<float>("val2");

    QTest::newRow("zero")  << 0.0f << 2.0f;
    QTest::newRow("one")   << 1.0f << 4.0f;
    QTest::newRow("ten")   << 10.0f << 20.0f;
}

void tst_qfloat16::arithOps()
{
    QFETCH(float, val1);
    QFETCH(float, val2);

    QVERIFY(qFuzzyCompare(float(qfloat16(val1) + qfloat16(val2)), val1 + val2));
    QVERIFY(qFuzzyCompare(float(qfloat16(val1) - qfloat16(val2)), val1 - val2));
    QVERIFY(qFuzzyCompare(float(qfloat16(val1) * qfloat16(val2)), val1 * val2));
    QVERIFY(qFuzzyCompare(float(qfloat16(val1) / qfloat16(val2)), val1 / val2));

    QVERIFY(qFuzzyCompare(qfloat16(val1) + val2, val1 + val2));
    QVERIFY(qFuzzyCompare(qfloat16(val1) - val2, val1 - val2));
    QVERIFY(qFuzzyCompare(qfloat16(val1) * val2, val1 * val2));
    QVERIFY(qFuzzyCompare(qfloat16(val1) / val2, val1 / val2));

    QVERIFY(qFuzzyCompare(val1 + qfloat16(val2), val1 + val2));
    QVERIFY(qFuzzyCompare(val1 - qfloat16(val2), val1 - val2));
    QVERIFY(qFuzzyCompare(val1 * qfloat16(val2), val1 * val2));
    QVERIFY(qFuzzyCompare(val1 / qfloat16(val2), val1 / val2));

    float r1 = 0.f;
    r1 += qfloat16(val2);
    QVERIFY(qFuzzyCompare(r1,val2));

    float r2 = 0.f;
    r2 -= qfloat16(val2);
    QVERIFY(qFuzzyCompare(r2,-val2));

    float r3 = 1.f;
    r3 *= qfloat16(val2);
    QVERIFY(qFuzzyCompare(r3,val2));

    float r4 = 1.f;
    r4 /= qfloat16(val2);
    QVERIFY(qFuzzyCompare(r4,1.f/val2));
}

#if defined DO_FULL_TEST
void tst_qfloat16::floatToFloat16Full_data()
{
    QTest::addColumn<quint32>("group");
    for (quint32 j = 0x00; j < 0x100; ++j)
        QTest::addRow("%02x", j) << j;

}

void tst_qfloat16::floatToFloat16Full()
{
    QFETCH(quint32, group);
    for (quint32 j = 0x00; j < 0x100; ++j) {
        quint32 data[1<<16];
        qfloat16 out[1<<16];
        qfloat16 expected[1<<16];
        float in[1<<16];

        for (int i = 0; i < (1<<16); ++i)
            data[i] = (group << 24) | (j << 16) | i;

        memcpy(in, data, (1<<16)*sizeof(float));

        for (int i = 0; i < (1<<16); ++i)
            expected[i] = qfloat16(in[i]);

        qFloatToFloat16(out, in, 1<<16);

        for (int i = 0; i < (1<<16); ++i) {
            if (out[i] != expected[i])
                QVERIFY(qIsNaN(out[i]) && qIsNaN(expected[i]));
        }
    }
}

void tst_qfloat16::floatFromFloat16Full()
{
    quint16 data[1<<16];
    float out[1<<16];
    float expected[1<<16];

    for (int i = 0; i < (1<<16); ++i)
        data[i] = i;

    const qfloat16 *in = reinterpret_cast<const qfloat16 *>(data);

    for (int i = 0; i < (1<<16); ++i)
        expected[i] = float(in[i]);

    qFloatFromFloat16(out, in, 1<<16);

    for (int i = 0; i < (1<<16); ++i)
        if (out[i] != expected[i])
            QVERIFY(qIsNaN(out[i]) && qIsNaN(expected[i]));
}
#endif

void tst_qfloat16::floatToFloat16()
{
    constexpr int count = 10000;
    float in[count];
    qfloat16 out[count];
    qfloat16 expected[count];

    for (int i = 0; i < count; ++i)
        in[i] = (i - count/2) * (1/13.f);

    for (int i = 0; i < count; ++i)
        expected[i] = qfloat16(in[i]);

    qFloatToFloat16(out, in, count);

    for (int i = 0; i < count; ++i)
        QVERIFY(out[i] == expected[i]);
}

void tst_qfloat16::floatFromFloat16()
{
    qfloat16 in[35];
    float out[35];
    float expected[35];

    for (int i = 0; i < 35; ++i)
        in[i] = qfloat16(i * (17.f / 3));

    for (int i = 0; i < 35; ++i)
        expected[i] = float(in[i]);

    qFloatFromFloat16(out, in, 35);

    for (int i = 0; i < 35; ++i)
        QCOMPARE(out[i], expected[i]);
}

static qfloat16 powf16(qfloat16 base, int raise)
{
    const qfloat16 one(1.f);
    if (raise < 0) {
        raise = -raise;
        base = one / base;
    }
    qfloat16 answer = (raise & 1) ? base : one;
    while (raise > 0) {
        raise >>= 1;
        base *= base;
        if (raise & 1)
            answer *= base;
    }
    return answer;
}

void tst_qfloat16::finite_data()
{
    using Bounds = std::numeric_limits<qfloat16>;
    QTest::addColumn<qfloat16>("value");
    QTest::addColumn<int>("mode");

    QTest::newRow("zero") << qfloat16(0) << FP_ZERO;
    QTest::newRow("-zero") << -qfloat16(0) << FP_ZERO;
    QTest::newRow("one") << qfloat16(1) << FP_NORMAL;
    QTest::newRow("-one") << qfloat16(-1) << FP_NORMAL;
    QTest::newRow("ten") << qfloat16(10) << FP_NORMAL;
    QTest::newRow("-ten") << qfloat16(-10) << FP_NORMAL;
    QTest::newRow("max") << Bounds::max() << FP_NORMAL;
    QTest::newRow("lowest") << Bounds::lowest() << FP_NORMAL;
    QTest::newRow("min") << Bounds::min() << FP_NORMAL;
    QTest::newRow("-min") << -Bounds::min() << FP_NORMAL;
    QTest::newRow("denorm_min") << Bounds::denorm_min() << FP_SUBNORMAL;
    QTest::newRow("-denorm_min") << -Bounds::denorm_min() << FP_SUBNORMAL;
}

void tst_qfloat16::finite()
{
    QFETCH(qfloat16, value);
    QFETCH(int, mode);
    QCOMPARE(value.isNormal(), mode == FP_NORMAL);
    QCOMPARE(value, value); // Fuzzy
    QVERIFY(value == value); // Exact
    QVERIFY(qIsFinite(value));
    QVERIFY(!qIsInf(value));
    QVERIFY(!qIsNaN(value));
    QCOMPARE(qFpClassify(value), mode);

    // *NOT* using QCOMPARE() on finite qfloat16 values, since that uses fuzzy
    // comparison, and we need exact here.
    const qfloat16 zero(0), plus(+1), minus(-1);
    const qfloat16 magnitude = (value < zero) ? -value : value;
    QVERIFY(value.copySign(plus) == magnitude);
    QVERIFY(value.copySign(minus) == -magnitude);
}

void tst_qfloat16::properties()
{
    using Bounds = std::numeric_limits<qfloat16>;
    QVERIFY(Bounds::is_specialized);
    QVERIFY(Bounds::is_signed);
    QVERIFY(!Bounds::is_integer);
    QVERIFY(!Bounds::is_exact);

    // While we'd like to check for __STDC_IEC_559__, as per ISO/IEC 9899:2011
    // Annex F (C11, normative for C++11), there are a few corner cases regarding
    // denormals where GHS compiler is relying hardware behavior that is not IEC
    // 559 compliant.

    // On GHS the compiler reports std::numeric_limits<float>::is_iec559 as false.
    // and the same supposed to be for qfloat16.
#if !defined(Q_CC_GHS)
    QVERIFY(Bounds::is_iec559);
#endif //Q_CC_GHS
#if QT_CONFIG(signaling_nan)
    // Technically, presence of NaN and infinities are implied from the above check, but that checkings GHS compiler complies.
    QVERIFY(Bounds::has_infinity && Bounds::has_quiet_NaN && Bounds::has_signaling_NaN);
#endif
    QVERIFY(Bounds::is_bounded);
    QVERIFY(!Bounds::is_modulo);
    QVERIFY(!Bounds::traps);
    QVERIFY(Bounds::has_infinity);
    QVERIFY(Bounds::has_quiet_NaN);
#if QT_CONFIG(signaling_nan)
    QVERIFY(Bounds::has_signaling_NaN);
#endif
#if !defined(Q_CC_GHS)
    QCOMPARE(Bounds::has_denorm, std::denorm_present);
#else
    // For GHS compiler the "denorm_indeterminite" is the expected return value.
    QCOMPARE(Bounds::has_denorm, std::denorm_indeterminate);
#endif // Q_CC_GHS
    QCOMPARE(Bounds::round_style, std::round_to_nearest);
    QCOMPARE(Bounds::radix, 2);
    // Untested: has_denorm_loss
}

void tst_qfloat16::limits() // See also: qNaN() and infinity()
{
    // *NOT* using QCOMPARE() on finite qfloat16 values, since that uses fuzzy
    // comparison, and we need exact here.
    using Bounds = std::numeric_limits<qfloat16>;

    // A few useful values:
    const qfloat16 zero(0), one(1), ten(10);

    // The specifics of minus zero:
    // (IEEE 754 seems to want -zero < zero, but -0. == 0. and -0.f == 0.f in C++.)
    QVERIFY(-zero <= zero);
    QVERIFY(-zero == zero);
    QVERIFY(!(-zero > zero));

    // digits in the mantissa, including the implicit 1 before the binary dot at its left:
    QVERIFY(qfloat16(1 << (Bounds::digits - 1)) + one > qfloat16(1 << (Bounds::digits - 1)));
    QVERIFY(qfloat16(1 << Bounds::digits) + one == qfloat16(1 << Bounds::digits));

    // There is a wilful of-by-one in how m(ax|in)_exponent are defined; they're
    // the lowest and highest n for which radix^{n-1} are normal and finite.
    const qfloat16 two(Bounds::radix);
    qfloat16 bit = powf16(two, Bounds::max_exponent - 1);
    QVERIFY(qIsFinite(bit));
    QVERIFY(qIsInf(bit * two));
    bit = powf16(two, Bounds::min_exponent - 1);
    QVERIFY(bit.isNormal());
    QCOMPARE(qFpClassify(bit), FP_NORMAL);
    QVERIFY(!(bit / two).isNormal());
    QCOMPARE(qFpClassify(bit / two), FP_SUBNORMAL);
    QVERIFY(bit / two > zero);

    // Base ten (with no matching off-by-one idiocy):
    // the lowest negative number n such that 10^n is a valid normalized value
    qfloat16 low10(powf16(ten, Bounds::min_exponent10));
    QVERIFY(low10 > zero);
    QVERIFY(low10.isNormal());
    low10 /= ten;
    QVERIFY(low10 == zero || !low10.isNormal());
    // the largest positive number n such that 10^n is a representable finite value
    qfloat16 high10(powf16(ten, Bounds::max_exponent10));
    QVERIFY(high10 > zero);
    QVERIFY(qIsFinite(high10));
    QVERIFY(!qIsFinite(high10 * ten));
    QCOMPARE(qFpClassify(high10), FP_NORMAL);

    // How many digits are significant ?  (Casts avoid linker errors ...)
    QCOMPARE(int(Bounds::digits10), 3); // ~9.88e-4 has enough sigificant digits:
    qfloat16 below(9.876e-4f), above(9.884e-4f); // both round to ~9.88e-4
    QVERIFY(below == above);
    QCOMPARE(int(Bounds::max_digits10), 5); // we need 5 to distinguish these two:
    QVERIFY(qfloat16(1000.5f) != qfloat16(1001.4f));

    // Actual limiting values of the type:
    const qfloat16 rose(one + Bounds::epsilon());
    QVERIFY(rose > one);
    QVERIFY(one + Bounds::epsilon() / two == one);

    QVERIFY(Bounds::max() > zero);
    QVERIFY(qIsInf(Bounds::max() * rose));

    QVERIFY(Bounds::lowest() < zero);
    QVERIFY(qIsInf(Bounds::lowest() * rose));

    QVERIFY(Bounds::min() > zero);
    QVERIFY(!(Bounds::min() / rose).isNormal());

    QVERIFY(Bounds::denorm_min() > zero);
    QVERIFY(Bounds::denorm_min() / two == zero);
    const qfloat16 under = (-Bounds::denorm_min()) / two;
    QVERIFY(under == -zero);
    QCOMPARE(qfloat16(1).copySign(under), qfloat16(-1));
}

void tst_qfloat16::mantissaOverflow()
{
    // Test we don't change category due to mantissa overflow when rounding.
    quint32 in = 0x7fffffff;
    float f;
    memcpy(&f, &in, 4);

    qfloat16 f16 = qfloat16(f);
    qfloat16 f16s[1];
    qFloatToFloat16(f16s, &f, 1);
    QCOMPARE(f16, f16s[0]);
    QVERIFY(qIsNaN(f16));
}

void tst_qfloat16::dataStream()
{
    QByteArray ba;
    QDataStream ds(&ba, QIODevice::ReadWrite);
    ds << qfloat16(1.5) << qfloat16(-1);
    QCOMPARE(ba.size(), 4);
    QCOMPARE(ds.status(), QDataStream::Ok);
    QCOMPARE(ba, QByteArray("\x3e\0\xbc\0", 4));

    ds.device()->seek(0);
    ds.resetStatus();
    ds.setByteOrder(QDataStream::LittleEndian);
    ds << qfloat16(0) << qfloat16(-1);
    QCOMPARE(ds.status(), QDataStream::Ok);
    QCOMPARE(ba, QByteArray("\0\0\0\xbc", 4));

    ds.device()->seek(0);
    ds.resetStatus();
    qfloat16 zero = 1;
    ds >> zero;
    QCOMPARE(ds.status(), QDataStream::Ok);
    QCOMPARE(zero, qfloat16(0));

    ds.device()->seek(0);
    ds.resetStatus();
    QMetaType mt = QMetaType(QMetaType::Float16);
    QVERIFY(mt.save(ds, &zero));

    ds.device()->seek(0);
    ds.resetStatus();
    zero = -1;
    QVERIFY(mt.load(ds, &zero));
    QCOMPARE(zero, qfloat16(0));
}

void tst_qfloat16::textStream()
{
    QString buffer;
    {
        QTextStream ts(&buffer);
        ts << qfloat16(0) << Qt::endl << qfloat16(1.5);
        QCOMPARE(ts.status(), QTextStream::Ok);
    }
    QCOMPARE(buffer, "0\n1.5");

    {
        QTextStream ts(&buffer);
        qfloat16 zero = qfloat16(-2.5), threehalves = 1234;
        ts >> zero >> threehalves;
        QCOMPARE(ts.status(), QTextStream::Ok);
        QCOMPARE(zero, qfloat16(0));
        QCOMPARE(threehalves, 1.5);
    }
}

QTEST_APPLESS_MAIN(tst_qfloat16)
#include "tst_qfloat16.moc"