[glib/gobject-speedups: 3/8] Keep a separate flag for notify handlers

[Matthias Clasen <matthiasc src gnome org>]

commit c34e11cf903f9d939eaac994eebb683eb495382c
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun May 15 07:52:10 2022 -0400

    Keep a separate flag for notify handlers
    
    We currently keep a flag for whether an object has
    ever had any signal handlers. But even if it had signal
    handlers, it may not have any notify handlers. Keep that
    information separately, so we can speed up property setting.

 gobject/gobject.c       | 27 ++++++++++++++++++++++-----
 gobject/gsignal.c       |  6 +++---
 gobject/gtype-private.h |  2 +-
 3 files changed, 26 insertions(+), 9 deletions(-)
---
diff --git a/gobject/gobject.c b/gobject/gobject.c
index 493cb3d024..a36b8ec748 100644
--- a/gobject/gobject.c
+++ b/gobject/gobject.c
@@ -151,6 +151,7 @@
     ((class)->constructor != g_object_constructor)
 #define CLASS_HAS_CUSTOM_CONSTRUCTED(class) \
     ((class)->constructed != g_object_constructed)
+#define CLASS_HAS_NOTIFY(class) ((class)->notify != NULL)
 
 #define CLASS_HAS_DERIVED_CLASS_FLAG 0x2
 #define CLASS_HAS_DERIVED_CLASS(class) \
@@ -168,8 +169,9 @@ enum {
   PROP_NONE
 };
 
-#define OPTIONAL_FLAG_IN_CONSTRUCTION 1<<0
-#define OPTIONAL_FLAG_HAS_SIGNAL_HANDLER 1<<1 /* Set if object ever had a signal handler */
+#define OPTIONAL_FLAG_IN_CONSTRUCTION    (1 << 0)
+#define OPTIONAL_FLAG_HAS_SIGNAL_HANDLER (1 << 1) /* Set if object ever had a signal handler */
+#define OPTIONAL_FLAG_HAS_NOTIFY_HANDLER (1 << 2) /* Same, specifically for "notify" */
 
 #if SIZEOF_INT == 4 && GLIB_SIZEOF_VOID_P == 8
 #define HAVE_OPTIONAL_FLAGS
@@ -1079,7 +1081,7 @@ object_unset_optional_flags (GObject *object,
 }
 
 gboolean
-_g_object_has_signal_handler  (GObject *object)
+_g_object_has_signal_handler (GObject *object)
 {
 #ifdef HAVE_OPTIONAL_FLAGS
   return (object_get_optional_flags (object) & OPTIONAL_FLAG_HAS_SIGNAL_HANDLER) != 0;
@@ -1088,11 +1090,26 @@ _g_object_has_signal_handler  (GObject *object)
 #endif
 }
 
+static inline gboolean
+_g_object_has_notify_handler (GObject *object)
+{
+#ifdef HAVE_OPTIONAL_FLAGS
+  return CLASS_HAS_NOTIFY (G_OBJECT_GET_CLASS (object)) ||
+         (object_get_optional_flags (object) & OPTIONAL_FLAG_HAS_NOTIFY_HANDLER) != 0;
+#else
+  return TRUE;
+#endif
+}
+
 void
-_g_object_set_has_signal_handler (GObject     *object)
+_g_object_set_has_signal_handler (GObject *object,
+                                  guint    signal_id)
 {
 #ifdef HAVE_OPTIONAL_FLAGS
-  object_set_optional_flags (object, OPTIONAL_FLAG_HAS_SIGNAL_HANDLER);
+  guint flags = OPTIONAL_FLAG_HAS_SIGNAL_HANDLER;
+  if (signal_id == gobject_signals[NOTIFY])
+    flags |= OPTIONAL_FLAG_HAS_NOTIFY_HANDLER;
+  object_set_optional_flags (object, flags);
 #endif
 }
 
diff --git a/gobject/gsignal.c b/gobject/gsignal.c
index fb85fd6ba2..8067334b9a 100644
--- a/gobject/gsignal.c
+++ b/gobject/gsignal.c
@@ -2422,7 +2422,7 @@ g_signal_connect_closure_by_id (gpointer  instance,
          Handler *handler = handler_new (signal_id, instance, after);
 
           if (G_TYPE_IS_OBJECT (node->itype))
-            _g_object_set_has_signal_handler ((GObject *)instance);
+            _g_object_set_has_signal_handler ((GObject *)instance, signal_id);
 
          handler_seq_no = handler->sequential_number;
          handler->detail = detail;
@@ -2489,7 +2489,7 @@ g_signal_connect_closure (gpointer     instance,
          Handler *handler = handler_new (signal_id, instance, after);
 
           if (G_TYPE_IS_OBJECT (node->itype))
-            _g_object_set_has_signal_handler ((GObject *)instance);
+            _g_object_set_has_signal_handler ((GObject *)instance, signal_id);
 
          handler_seq_no = handler->sequential_number;
          handler->detail = detail;
@@ -2593,7 +2593,7 @@ g_signal_connect_data (gpointer       instance,
          Handler *handler = handler_new (signal_id, instance, after);
 
           if (G_TYPE_IS_OBJECT (node->itype))
-            _g_object_set_has_signal_handler ((GObject *)instance);
+            _g_object_set_has_signal_handler ((GObject *)instance, signal_id);
 
          handler_seq_no = handler->sequential_number;
          handler->detail = detail;
diff --git a/gobject/gtype-private.h b/gobject/gtype-private.h
index 2e0afdd5d4..a9b1f73c02 100644
--- a/gobject/gtype-private.h
+++ b/gobject/gtype-private.h
@@ -94,7 +94,7 @@ void        _g_closure_invoke_va (GClosure       *closure,
                                  GType          *param_types);
 
 gboolean    _g_object_has_signal_handler     (GObject     *object);
-void        _g_object_set_has_signal_handler (GObject     *object);
+void        _g_object_set_has_signal_handler (GObject     *object, guint signal_id);
 
 /**
  * _G_DEFINE_TYPE_EXTENDED_WITH_PRELUDE: