V4: add counters for built-in function invocations.

When enabled, counters for the number of invocations of built-in runtime
functions are dumped when the application exits normally.

Note: this gives a penalty on execution speed. It is not meant to be
super light-weight, but as a tool to have an indication which functions
get called most, thereby helping to indicate which code-paths to
optimize.

Change-Id: Ica701f36a578affcce5ee8414532259972e5ede5
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

1 files changed, 26 insertions, 8 deletions

diff --git a/src/qml/jsruntime/qv4runtime_p.h b/src/qml/jsruntime/qv4runtime_p.h
index d1ca86fddd..14d123e512 100644
--- a/src/qml/jsruntime/qv4runtime_p.h
+++ b/src/qml/jsruntime/qv4runtime_p.h
@@ -57,18 +57,36 @@
 
 //#include <wtf/MathExtras.h>
 
-#ifdef DO_TRACE_INSTR
-#  define TRACE1(x) fprintf(stderr, "    %s\n", __FUNCTION__);
-#  define TRACE2(x, y) fprintf(stderr, "    %s\n", __FUNCTION__);
-#else
-#  define TRACE1(x)
-#  define TRACE2(x, y)
-#endif // TRACE1
-
 QT_BEGIN_NAMESPACE
 
+#undef QV4_COUNT_RUNTIME_FUNCTIONS
+
 namespace QV4 {
 
+#ifdef QV4_COUNT_RUNTIME_FUNCTIONS
+class RuntimeCounters
+{
+public:
+    RuntimeCounters();
+    ~RuntimeCounters();
+
+    static RuntimeCounters *instance;
+
+    void count(const char *func, uint tag);
+    void count(const char *func, uint tag1, uint tag2);
+
+private:
+    struct Data;
+    Data *d;
+};
+
+#  define TRACE1(x) RuntimeCounters::instance->count(Q_FUNC_INFO, x.type());
+#  define TRACE2(x, y) RuntimeCounters::instance->count(Q_FUNC_INFO, x.type(), y.type());
+#else
+#  define TRACE1(x)
+#  define TRACE2(x, y)
+#endif // QV4_COUNT_RUNTIME_FUNCTIONS
+
 enum TypeHint {
     PREFERREDTYPE_HINT,
     NUMBER_HINT,