Reduce the size of signal parameters in qml cache data

We can reduce the distinction between a built-in type or a custom type
down to a single bit.

Change-Id: Ibe15d35357aa8c3948809f981221df29a40c400b
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

2 files changed, 12 insertions, 7 deletions

diff --git a/src/qml/compiler/qqmlirbuilder.cpp b/src/qml/compiler/qqmlirbuilder.cpp
index 7dc21152a4..1f3e0cdaca 100644
--- a/src/qml/compiler/qqmlirbuilder.cpp
+++ b/src/qml/compiler/qqmlirbuilder.cpp
@@ -833,8 +833,9 @@ bool IRBuilder::visit(QQmlJS::AST::UiPublicMember *node)
                 if (memberType.at(0).isUpper()) {
                     // Must be a QML object type.
                     // Lazily determine type during compilation.
-                    param->type = QV4::CompiledData::Property::Custom;
-                    param->customTypeNameIndex = registerString(memberType);
+                    param->indexIsBuiltinType = false;
+                    param->typeNameIndexOrBuiltinType = registerString(memberType);
+                    Q_ASSERT(quint32(jsGenerator->getStringId(memberType)) < (1u << 31));
                 } else {
                     QString errStr = QCoreApplication::translate("QQmlParser","Invalid signal parameter type: ");
                     errStr.append(memberType);
@@ -843,8 +844,9 @@ bool IRBuilder::visit(QQmlJS::AST::UiPublicMember *node)
                 }
             } else {
                 // the parameter is a known basic type
-                param->type = type->type;
-                param->customTypeNameIndex = emptyStringIndex;
+                param->indexIsBuiltinType = true;
+                param->typeNameIndexOrBuiltinType = type->type;
+                Q_ASSERT(quint32(type->type) < (1u << 31));
             }
 
             param->nameIndex = registerString(p->name.toString());
diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h
index 8f427e0a7f..1656fd84aa 100644
--- a/src/qml/compiler/qv4compileddata_p.h
+++ b/src/qml/compiler/qv4compileddata_p.h
@@ -605,10 +605,13 @@ static_assert(sizeof(Enum) == 12, "Enum structure needs to have the expected siz
 struct Parameter
 {
     quint32_le nameIndex;
-    quint32_le type;
-    quint32_le customTypeNameIndex;
+    union {
+        quint32 _dummy;
+        quint32_le_bitfield<0, 1> indexIsBuiltinType;
+        quint32_le_bitfield<1, 31> typeNameIndexOrBuiltinType;
+    };
 };
-static_assert(sizeof(Parameter) == 12, "Parameter 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(Parameter) == 8, "Parameter structure needs to have the expected size to be binary compatible on disk when generated by host compiler and loaded by target");
 
 struct Signal
 {