Reduce the size of Property fields in type compilation data

We can shave off 4 bytes of each property declaration by sharing the
bits for the custom type name index or the builtin type enum.

Change-Id: I77071cbef66c5a83b3e7e281dba3a435d3c68b39
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 24 insertions, 7 deletions

diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h
index 9123f9f0ec..639595509a 100644
--- a/src/qml/compiler/qv4compileddata_p.h
+++ b/src/qml/compiler/qv4compileddata_p.h
@@ -642,18 +642,35 @@ struct Property
 {
     enum Type : unsigned int { Var = 0, Variant, Int, Bool, Real, String, Url, Color,
                 Font, Time, Date, DateTime, Rect, Point, Size,
-                Vector2D, Vector3D, Vector4D, Matrix4x4, Quaternion,
-                Custom, CustomList };
+                Vector2D, Vector3D, Vector4D, Matrix4x4, Quaternion, InvalidBuiltin };
 
     quint32_le nameIndex;
     union {
-        quint32_le_bitfield<0, 31> type;
+        quint32_le_bitfield<0, 29> builtinTypeOrTypeNameIndex;
+        quint32_le_bitfield<29, 1> isBuiltinType;
+        quint32_le_bitfield<30, 1> isList;
         quint32_le_bitfield<31, 1> isReadOnly;
     };
-    quint32_le customTypeNameIndex; // If type >= Custom
+
     Location location;
+
+    void setBuiltinType(Type t)
+    {
+        builtinTypeOrTypeNameIndex = t;
+        isBuiltinType = true;
+    }
+    Type builtinType() const {
+        if (isBuiltinType)
+            return static_cast<Type>(quint32(builtinTypeOrTypeNameIndex));
+        return InvalidBuiltin;
+    }
+    void setCustomType(int nameIndex)
+    {
+        builtinTypeOrTypeNameIndex = nameIndex;
+        isBuiltinType = false;
+    }
 };
-static_assert(sizeof(Property) == 16, "Property structure needs to have the expected size to be binary compatible on disk when generated by host compiler and loaded by target");
+static_assert(sizeof(Property) == 12, "Property structure needs to have the expected size to be binary compatible on disk when generated by host compiler and loaded by target");
 
 struct Alias {
     enum Flags : unsigned int {
@@ -1044,8 +1061,8 @@ struct TypeReferenceMap : QHash<int, TypeReference>
         auto prop = obj->propertiesBegin();
         auto propEnd = obj->propertiesEnd();
         for ( ; prop != propEnd; ++prop) {
-            if (prop->type >= QV4::CompiledData::Property::Custom) {
-                TypeReference &r = this->add(prop->customTypeNameIndex, prop->location);
+            if (!prop->isBuiltinType) {
+                TypeReference &r = this->add(prop->builtinTypeOrTypeNameIndex, prop->location);
                 r.errorWhenNotFound = true;
             }
         }