qfloat16: make it a built-in metatype

I've reserved the IDs for int128, uint128, bfloat16, and float128,
because the mask in qvariant.cpp's qIsNumericType() requires primitives
to be less than 64 to operate properly.

Added a QMetaType/QDataStream test to confirm it is indeed built-in.

Change-Id: I3d74c753055744deb8acfffd17247f7f57bada02
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

src/corelib/kernel/qmetatype.cpp

@@ -353,8 +353,12 @@ const char *QtMetaTypePrivate::typedefNameForType(const QtPrivate::QMetaTypeInte
     \value SChar \c{signed char}
     \value UChar \c{unsigned char}
     \value Float \c float
+    \value Float16 qfloat16
+    \omitvalue Float128
+    \omitvalue BFloat16
+    \omitvalue Int128
+    \omitvalue UInt128
     \value QObjectStar QObject *
-    \value QVariant QVariant
 
     \value QCursor QCursor
     \value QDate QDate
@@ -413,6 +417,7 @@ const char *QtMetaTypePrivate::typedefNameForType(const QtPrivate::QMetaTypeInte
     \value QPersistentModelIndex QPersistentModelIndex (introduced in Qt 5.5)
     \value QUuid QUuid
     \value QByteArrayList QByteArrayList
+    \value QVariant QVariant
 
     \value User  Base value for user types
     \value UnknownType This is an invalid type id. It is returned from QMetaType for types that are not registered

src/corelib/kernel/qmetatype.h

@@ -10,13 +10,14 @@
 #include <QtCore/qatomic.h>
 #include <QtCore/qbytearray.h>
 #include <QtCore/qcompare.h>
-#include <QtCore/qscopeguard.h>
 #include <QtCore/qdatastream.h>
+#include <QtCore/qfloat16.h>
+#include <QtCore/qhashfunctions.h>
 #include <QtCore/qiterable.h>
 #ifndef QT_NO_QOBJECT
 #include <QtCore/qobjectdefs.h>
 #endif
-#include <QtCore/qhashfunctions.h>
+#include <QtCore/qscopeguard.h>
 
 #include <array>
 #include <new>
@@ -121,6 +122,7 @@ inline constexpr int qMetaTypeId();
     F(QCborValue, 53, QCborValue) \
     F(QCborArray, 54, QCborArray) \
     F(QCborMap, 55, QCborMap) \
+    F(Float16, 63, qfloat16) \
     QT_FOR_EACH_STATIC_ITEMMODEL_CLASS(F)
 
 #define QT_FOR_EACH_STATIC_CORE_POINTER(F)\
@@ -317,7 +319,7 @@ public:
         QT_FOR_EACH_STATIC_TYPE(QT_DEFINE_METATYPE_ID)
 
         FirstCoreType = Bool,
-        LastCoreType = QVariantPair,
+        LastCoreType = Float16,
         FirstGuiType = QFont,
         LastGuiType = QColorSpace,
         FirstWidgetsType = QSizePolicy,
@@ -349,6 +351,7 @@ public:
         QVariantMap = 8, QVariantList = 9, QVariantHash = 28, QVariantPair = 58,
         QCborSimpleType = 52, QCborValue = 53, QCborArray = 54, QCborMap = 55,
         Char16 = 56, Char32 = 57,
+        Int128 = 59, UInt128 = 60, Float128 = 61, BFloat16 = 62, Float16 = 63,
 
         // Gui types
         QFont = 0x1000, QPixmap = 0x1001, QBrush = 0x1002, QColor = 0x1003, QPalette = 0x1004,

src/corelib/kernel/qvariant.cpp

@@ -183,6 +183,8 @@ static std::optional<qreal> qConvertToRealNumber(const QVariant::Private *d)
         return qreal(d->get<double>());
     case QMetaType::Float:
         return qreal(d->get<float>());
+    case QMetaType::Float16:
+        return qreal(d->get<qfloat16>());
     case QMetaType::ULongLong:
     case QMetaType::UInt:
     case QMetaType::UChar:
@@ -2161,7 +2163,7 @@ static bool qIsNumericType(uint tp)
 
 static bool qIsFloatingPoint(uint tp)
 {
-    return tp == QMetaType::Double || tp == QMetaType::Float;
+    return tp == QMetaType::Double || tp == QMetaType::Float || tp == QMetaType::Float16;
 }
 
 static bool canBeNumericallyCompared(const QtPrivate::QMetaTypeInterface *iface1,

tests/auto/corelib/global/qfloat16/tst_qfloat16.cpp

@@ -4,6 +4,7 @@
 
 #include <QTest>
 #include <QFloat16>
+#include <QMetaType>
 #include <QTextStream>
 
 #include <math.h>
@@ -656,6 +657,17 @@ void tst_qfloat16::dataStream()
     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()

tests/auto/corelib/kernel/qmetatype/tst_qmetatype_common.h

@@ -129,6 +129,9 @@ template<> struct TestValueFactory<QMetaType::UChar> {
 template<> struct TestValueFactory<QMetaType::Float> {
     static float *create() { return new float(FLT_MIN); }
 };
+template<> struct TestValueFactory<QMetaType::Float16> {
+    static auto create() { return new qfloat16(std::numeric_limits<qfloat16>::min()); }
+};
 template<> struct TestValueFactory<QMetaType::QObjectStar> {
     static QObject * *create() { return new QObject *(0); }
 };