Refactor our NaN boxing to be more efficient

* Use a unified way to store all Managed objects inside
a Value, instead of distinguishing between strings
and other objects.

* On 64 bit we store pointers as pointers, so accessing them
through Scoped<> objects is cheap. This implies that doubles
are now stored in a mangled form (xor'ed with a mask).

Change-Id: I582e0fb167a62c0c527c6bfa3452550e37944069
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

1 files changed, 3 insertions, 4 deletions

diff --git a/src/qml/jsruntime/qv4debugging.cpp b/src/qml/jsruntime/qv4debugging.cpp
index 2b6dc4616c..34b72e95fb 100644
--- a/src/qml/jsruntime/qv4debugging.cpp
+++ b/src/qml/jsruntime/qv4debugging.cpp
@@ -214,12 +214,11 @@ static void realDumpValue(QV4::Value v, QV4::ExecutionContext *ctx, std::string
 
     cout << prefix << "tag: " << hex << v.tag << dec << endl << prefix << "\t-> ";
     switch (v.type()) {
-    case Value::Undefined_Type: cout << "Undefined" << endl; return;
-    case Value::Null_Type: cout << "Null" << endl; return;
+    case Value::Undefined_Type: cout << "Undefined"; return;
+    case Value::Null_Type: cout << "Null"; return;
     case Value::Boolean_Type: cout << "Boolean"; break;
     case Value::Integer_Type: cout << "Integer"; break;
-    case Value::Object_Type: cout << "Object"; break;
-    case Value::String_Type: cout << "String"; break;
+    case Value::Managed_Type: cout << v.managed()->className().toUtf8().data(); break;
     default: cout << "UNKNOWN" << endl; return;
     }
     cout << endl;