Cleanup QTypeInfo

Remove QTypeInfo::isStatic, as that's not used anymore in Qt 6.
Also remove sizeOf, it's unused, and we have QMetaType for that if
required.
Remove all typeinfo declaractions for trivial types, as the default
template covers them correctly nowadays.

Finally set up a better default for isPointer, and do some smaller
cleanups all over the place.

Change-Id: I6758ed37dfc701feaaf0ff105cc95e32da9f9c33
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 11 insertions, 118 deletions

diff --git a/src/corelib/global/qtypeinfo.h b/src/corelib/global/qtypeinfo.h
index e45347ee10..30db5c4487 100644
--- a/src/corelib/global/qtypeinfo.h
+++ b/src/corelib/global/qtypeinfo.h
@@ -55,16 +55,7 @@ class QDebug;
 */
 
 template <typename T>
-static constexpr bool qIsRelocatable()
-{
-    return std::is_trivially_copyable<T>::value && std::is_trivially_destructible<T>::value;
-}
-
-template <typename T>
-static constexpr bool qIsTrivial()
-{
-    return std::is_trivial<T>::value;
-}
+static constexpr bool qIsRelocatable =  std::is_trivially_copyable_v<T> && std::is_trivially_destructible_v<T>;
 
 /*
   The catch-all template.
@@ -75,12 +66,10 @@ class QTypeInfo
 {
 public:
     enum {
-        isPointer = false,
-        isIntegral = std::is_integral<T>::value,
-        isComplex = !qIsTrivial<T>(),
-        isStatic = true,
-        isRelocatable = qIsRelocatable<T>(),
-        sizeOf = sizeof(T)
+        isPointer = std::is_pointer_v<T>,
+        isIntegral = std::is_integral_v<T>,
+        isComplex = !std::is_trivial_v<T>,
+        isRelocatable = qIsRelocatable<T>,
     };
 };
 
@@ -92,53 +81,11 @@ public:
         isPointer = false,
         isIntegral = false,
         isComplex = false,
-        isStatic = false,
         isRelocatable = false,
-        sizeOf = 0
-    };
-};
-
-template <typename T>
-class QTypeInfo<T*>
-{
-public:
-    enum {
-        isPointer = true,
-        isIntegral = false,
-        isComplex = false,
-        isStatic = false,
-        isRelocatable = true,
-        sizeOf = sizeof(T*)
     };
 };
 
 /*!
-    \class QTypeInfoQuery
-    \inmodule QtCore
-    \internal
-    \brief QTypeInfoQuery is used to query the values of a given QTypeInfo<T>
-
-    We use it because there may be some QTypeInfo<T> specializations in user
-    code that don't provide certain flags that we added after Qt 5.0. They are:
-    \list
-      \li isRelocatable: defaults to !isStatic
-    \endlist
-
-    DO NOT specialize this class elsewhere.
-*/
-// apply defaults for a generic QTypeInfo<T> that didn't provide the new values
-template <typename T, typename = void>
-struct QTypeInfoQuery : public QTypeInfo<T>
-{
-    enum { isRelocatable = !QTypeInfo<T>::isStatic };
-};
-
-// if QTypeInfo<T>::isRelocatable exists, use it
-template <typename T>
-struct QTypeInfoQuery<T, typename std::enable_if<QTypeInfo<T>::isRelocatable || true>::type> : public QTypeInfo<T>
-{};
-
-/*!
     \class QTypeInfoMerger
     \inmodule QtCore
     \internal
@@ -163,12 +110,10 @@ class QTypeInfoMerger
 {
     static_assert(sizeof...(Ts) > 0);
 public:
-    static constexpr bool isComplex = ((QTypeInfoQuery<Ts>::isComplex) || ...);
-    static constexpr bool isStatic =  ((QTypeInfoQuery<Ts>::isStatic) || ...);
-    static constexpr bool isRelocatable = ((QTypeInfoQuery<Ts>::isRelocatable) && ...);
+    static constexpr bool isComplex = ((QTypeInfo<Ts>::isComplex) || ...);
+    static constexpr bool isRelocatable = ((QTypeInfo<Ts>::isRelocatable) && ...);
     static constexpr bool isPointer = false;
     static constexpr bool isIntegral = false;
-    static constexpr std::size_t sizeOf = sizeof(T);
 };
 
 #define Q_DECLARE_MOVABLE_CONTAINER(CONTAINER) \
@@ -182,8 +127,6 @@ public: \
         isIntegral = false, \
         isComplex = true, \
         isRelocatable = true, \
-        isStatic = false, \
-        sizeOf = sizeof(CONTAINER<T>) \
     }; \
 }
 
@@ -204,9 +147,7 @@ public: \
         isPointer = false, \
         isIntegral = false, \
         isComplex = true, \
-        isStatic = false, \
         isRelocatable = true, \
-        sizeOf = sizeof(CONTAINER<K, V>) \
     }; \
 }
 
@@ -228,10 +169,9 @@ Q_DECLARE_MOVABLE_CONTAINER(QMultiHash);
 enum { /* TYPEINFO flags */
     Q_COMPLEX_TYPE = 0,
     Q_PRIMITIVE_TYPE = 0x1,
-    Q_STATIC_TYPE = 0,
-    Q_MOVABLE_TYPE = 0x2,               // ### Qt6: merge movable and relocatable once QList no longer depends on it
+    Q_RELOCATABLE_TYPE = 0x2,
+    Q_MOVABLE_TYPE = 0x2,
     Q_DUMMY_TYPE = 0x4,
-    Q_RELOCATABLE_TYPE = 0x8
 };
 
 #define Q_DECLARE_TYPEINFO_BODY(TYPE, FLAGS) \
@@ -239,14 +179,11 @@ class QTypeInfo<TYPE > \
 { \
 public: \
     enum { \
-        isComplex = (((FLAGS) & Q_PRIMITIVE_TYPE) == 0) && !qIsTrivial<TYPE>(), \
-        isStatic = (((FLAGS) & (Q_MOVABLE_TYPE | Q_PRIMITIVE_TYPE)) == 0), \
-        isRelocatable = !isStatic || ((FLAGS) & Q_RELOCATABLE_TYPE) || qIsRelocatable<TYPE>(), \
+        isComplex = (((FLAGS) & Q_PRIMITIVE_TYPE) == 0) && !std::is_trivial_v<TYPE>, \
+        isRelocatable = !isComplex || ((FLAGS) & Q_RELOCATABLE_TYPE) || qIsRelocatable<TYPE>, \
         isPointer = false, \
         isIntegral = std::is_integral< TYPE >::value, \
-        sizeOf = sizeof(TYPE) \
     }; \
-    static inline const char *name() { return #TYPE; } \
 }
 
 #define Q_DECLARE_TYPEINFO(TYPE, FLAGS) \
@@ -283,50 +220,6 @@ inline void swap(TYPE &value1, TYPE &value2) \
 #define Q_DECLARE_SHARED_NOT_MOVABLE_UNTIL_QT6(TYPE) \
                                Q_DECLARE_SHARED_IMPL(TYPE, QT_VERSION >= QT_VERSION_CHECK(6,0,0) ? Q_MOVABLE_TYPE : Q_RELOCATABLE_TYPE)
 
-/*
-   QTypeInfo primitive specializations
-*/
-Q_DECLARE_TYPEINFO(bool, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(char, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(signed char, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(uchar, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(short, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(ushort, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(int, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(uint, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(long, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(ulong, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(qint64, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(quint64, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(float, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(double, Q_PRIMITIVE_TYPE);
-
-#if QT_VERSION >= QT_VERSION_CHECK(6,0,0)
-// ### Qt 6: remove the other branch
-// This was required so that QList<T> for these types allocates out of the array storage
-Q_DECLARE_TYPEINFO(long double, Q_PRIMITIVE_TYPE);
-#  ifdef Q_COMPILER_UNICODE_STRINGS
-Q_DECLARE_TYPEINFO(char16_t, Q_PRIMITIVE_TYPE);
-Q_DECLARE_TYPEINFO(char32_t, Q_PRIMITIVE_TYPE);
-#  endif
-#  if !defined(Q_CC_MSVC) || defined(_NATIVE_WCHAR_T_DEFINED)
-Q_DECLARE_TYPEINFO(wchar_t, Q_PRIMITIVE_TYPE);
-#  endif
-#else
-#  ifndef Q_OS_DARWIN
-Q_DECLARE_TYPEINFO(long double, Q_PRIMITIVE_TYPE);
-#  else
-Q_DECLARE_TYPEINFO(long double, Q_RELOCATABLE_TYPE);
-#  endif
-#  ifdef Q_COMPILER_UNICODE_STRINGS
-Q_DECLARE_TYPEINFO(char16_t, Q_RELOCATABLE_TYPE);
-Q_DECLARE_TYPEINFO(char32_t, Q_RELOCATABLE_TYPE);
-#  endif
-#  if !defined(Q_CC_MSVC) || defined(_NATIVE_WCHAR_T_DEFINED)
-Q_DECLARE_TYPEINFO(wchar_t, Q_RELOCATABLE_TYPE);
-#  endif
-#endif // Qt 6
-
 namespace QTypeTraits
 {