[glib/freeze-shenanigans: 17/17] Avoid atomics during construction

[Matthias Clasen <matthiasc src gnome org>]

commit 7e7ddfde1246280e7707c5178d9ab1d38050c7ea
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Jun 12 12:00:09 2022 -0400

    Avoid atomics during construction
    
    During construction, we have exclusive access to
    the object, so there is no need to use atomics
    for setting or reading the optional_flags member.

 gobject/gobject.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 57 insertions(+), 4 deletions(-)
---
diff --git a/gobject/gobject.c b/gobject/gobject.c
index 039a622deb..c95f2915bd 100644
--- a/gobject/gobject.c
+++ b/gobject/gobject.c
@@ -1176,6 +1176,21 @@ object_get_optional_flags (GObject *object)
 #endif
 }
 
+/* Variant of object_get_optional_flags for when
+ * we know that we have exclusive access (during
+ * construction)
+ */
+static inline guint
+object_get_optional_flags_X (GObject *object)
+{
+#ifdef HAVE_OPTIONAL_FLAGS
+  GObjectReal *real = (GObjectReal *)object;
+  return real->optional_flags;
+#else
+  return 0;
+#endif
+}
+
 static inline void
 object_set_optional_flags (GObject *object,
                           guint flags)
@@ -1186,6 +1201,19 @@ object_set_optional_flags (GObject *object,
 #endif
 }
 
+/* Variant for when we have exclusive access
+ * (during construction)
+ */
+static inline void
+object_set_optional_flags_X (GObject *object,
+                             guint flags)
+{
+#ifdef HAVE_OPTIONAL_FLAGS
+  GObjectReal *real = (GObjectReal *)object;
+  real->optional_flags |= flags;
+#endif
+}
+
 static inline void
 object_unset_optional_flags (GObject *object,
                             guint flags)
@@ -1196,6 +1224,19 @@ object_unset_optional_flags (GObject *object,
 #endif
 }
 
+/* Variant for when we have exclusive access
+ * (during construction)
+ */
+static inline void
+object_unset_optional_flags_X (GObject *object,
+                               guint flags)
+{
+#ifdef HAVE_OPTIONAL_FLAGS
+  GObjectReal *real = (GObjectReal *)object;
+  real->optional_flags &= ~flags;
+#endif
+}
+
 gboolean
 _g_object_has_signal_handler (GObject *object)
 {
@@ -1217,6 +1258,17 @@ _g_object_has_notify_handler (GObject *object)
 #endif
 }
 
+static inline gboolean
+_g_object_has_notify_handler_X (GObject *object)
+{
+#ifdef HAVE_OPTIONAL_FLAGS
+  return CLASS_HAS_NOTIFY (G_OBJECT_GET_CLASS (object)) ||
+         (object_get_optional_flags_X (object) & OPTIONAL_FLAG_HAS_NOTIFY_HANDLER) != 0;
+#else
+  return TRUE;
+#endif
+}
+
 void
 _g_object_set_has_signal_handler (GObject *object,
                                   guint    signal_id)
@@ -1243,7 +1295,7 @@ static inline void
 set_object_in_construction (GObject *object)
 {
 #ifdef HAVE_OPTIONAL_FLAGS
-  object_set_optional_flags (object, OPTIONAL_FLAG_IN_CONSTRUCTION);
+  object_set_optional_flags_X (object, OPTIONAL_FLAG_IN_CONSTRUCTION);
 #else
   g_datalist_id_set_data (&object->qdata, quark_in_construction, object);
 #endif
@@ -1253,7 +1305,7 @@ static inline void
 unset_object_in_construction (GObject *object)
 {
 #ifdef HAVE_OPTIONAL_FLAGS
-  object_unset_optional_flags (object, OPTIONAL_FLAG_IN_CONSTRUCTION);
+  object_unset_optional_flags_X (object, OPTIONAL_FLAG_IN_CONSTRUCTION);
 #else
   g_datalist_id_set_data (&object->qdata, quark_in_construction, NULL);
 #endif
@@ -2132,7 +2184,8 @@ g_object_new_with_custom_constructor (GObjectClass          *class,
 
   if (CLASS_HAS_PROPS (class))
     {
-      if (_g_object_has_notify_handler (object))
+      if ((newly_constructed && _g_object_has_notify_handler_X (object)) ||
+          _g_object_has_notify_handler (object))
         {
           /* This may or may not have been setup in g_object_init().
            * If it hasn't, we do it now.
@@ -2181,7 +2234,7 @@ g_object_new_internal (GObjectClass          *class,
     {
       GSList *node;
 
-      if (_g_object_has_notify_handler (object))
+      if (_g_object_has_notify_handler_X (object))
         {
           /* This may or may not have been setup in g_object_init().
            * If it hasn't, we do it now.