From 827c208cbf9cc0ef17b8c4531a40aafe1edc3f01 Mon Sep 17 00:00:00 2001
From: Emmanuele Bassi <ebassi@gnome.org>
Date: Mon, 4 Jun 2018 11:38:40 +0100
Subject: [PATCH] Use macros for refcount types API

If we're using GCC we can use __extension__ to inline the grefcount and
gatomicrefcount API, and avoid the function call.

These macros are only enabled if G_DISABLE_CHECKS is defined, as they
remove critical warnings when the reference counters achieve saturation.
---
 glib/grefcount.c | 20 +++++++-------
 glib/grefcount.h | 70 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+), 10 deletions(-)

diff --git a/glib/grefcount.c b/glib/grefcount.c
index 10e35a217..37085316b 100644
--- a/glib/grefcount.c
+++ b/glib/grefcount.c
@@ -89,7 +89,7 @@
  * Since: 2.58
  */
 void
-g_ref_count_init (grefcount *rc)
+(g_ref_count_init) (grefcount *rc)
 {
   g_return_if_fail (rc != NULL);
 
@@ -114,7 +114,7 @@ g_ref_count_init (grefcount *rc)
  * Since: 2.58
  */
 void
-g_ref_count_inc (grefcount *rc)
+(g_ref_count_inc) (grefcount *rc)
 {
   grefcount rrc;
 
@@ -147,7 +147,7 @@ g_ref_count_inc (grefcount *rc)
  * Since: 2.58
  */
 gboolean
-g_ref_count_dec (grefcount *rc)
+(g_ref_count_dec) (grefcount *rc)
 {
   grefcount rrc;
 
@@ -179,8 +179,8 @@ g_ref_count_dec (grefcount *rc)
  * Since: 2.58
  */
 gboolean
-g_ref_count_compare (grefcount *rc,
-                     gint       val)
+(g_ref_count_compare) (grefcount *rc,
+                       gint       val)
 {
   grefcount rrc;
 
@@ -204,7 +204,7 @@ g_ref_count_compare (grefcount *rc,
  * Since: 2.58
  */
 void
-g_atomic_ref_count_init (gatomicrefcount *arc)
+(g_atomic_ref_count_init) (gatomicrefcount *arc)
 {
   g_return_if_fail (arc != NULL);
 
@@ -229,7 +229,7 @@ g_atomic_ref_count_init (gatomicrefcount *arc)
  * Since: 2.58
  */
 void
-g_atomic_ref_count_inc (gatomicrefcount *arc)
+(g_atomic_ref_count_inc) (gatomicrefcount *arc)
 {
   g_return_if_fail (arc != NULL);
   g_return_if_fail (g_atomic_int_get (arc) > 0);
@@ -254,7 +254,7 @@ g_atomic_ref_count_inc (gatomicrefcount *arc)
  * Since: 2.58
  */
 gboolean
-g_atomic_ref_count_dec (gatomicrefcount *arc)
+(g_atomic_ref_count_dec) (gatomicrefcount *arc)
 {
   g_return_val_if_fail (arc != NULL, FALSE);
   g_return_val_if_fail (g_atomic_int_get (arc) > 0, FALSE);
@@ -275,8 +275,8 @@ g_atomic_ref_count_dec (gatomicrefcount *arc)
  * Since: 2.58
  */
 gboolean
-g_atomic_ref_count_compare (gatomicrefcount *arc,
-                            gint             val)
+(g_atomic_ref_count_compare) (gatomicrefcount *arc,
+                              gint             val)
 {
   g_return_val_if_fail (arc != NULL, FALSE);
   g_return_val_if_fail (val >= 0, FALSE);
diff --git a/glib/grefcount.h b/glib/grefcount.h
index b24c71e8c..dec9a5ffb 100644
--- a/glib/grefcount.h
+++ b/glib/grefcount.h
@@ -47,6 +47,76 @@ GLIB_AVAILABLE_IN_2_58
 gboolean        g_atomic_ref_count_compare      (gatomicrefcount *arc,
                                                  gint             val);
 
+/* On GCC we can use __extension__ to inline the API without using
+ * ancillary functions; we only do this when disabling checks, as
+ * it disables warnings when saturating the reference counters
+ */
+#if defined(__GNUC__) && defined(G_DISABLE_CHECKS)
+
+# define g_ref_count_init(rc) \
+  (G_GNUC_EXTENSION ({ \
+    G_STATIC_ASSERT (sizeof *(rc) == sizeof (grefcount)); \
+    (void) (0 ? *(rc) ^ *(rc) : 1); \
+    *(rc) = -1; \
+  }))
+
+# define g_ref_count_inc(rc) \
+  (G_GNUC_EXTENSION ({ \
+    G_STATIC_ASSERT (sizeof *(rc) == sizeof (grefcount)); \
+    (void) (0 ? *(rc) ^ *(rc) : 1); \
+    if (*(rc) == G_MININT) ; else { \
+      *(rc) -= 1; \
+    } \
+  }))
+
+# define g_ref_count_dec(rc) \
+  (G_GNUC_EXTENSION ({ \
+    G_STATIC_ASSERT (sizeof *(rc) == sizeof (grefcount)); \
+    grefcount __rc = *(rc); \
+    __rc += 1; \
+    if (__rc == 0) ; else { \
+      *(rc) = __rc; \
+    } \
+    (gboolean) (__rc == 0); \
+  }))
+
+# define g_ref_count_compare(rc,val) \
+  (G_GNUC_EXTENSION ({ \
+    G_STATIC_ASSERT (sizeof *(rc) == sizeof (grefcount)); \
+    (void) (0 ? *(rc) ^ (val) : 1); \
+    (gboolean) (*(rc) == -(val)); \
+  }))
+
+# define g_atomic_ref_count_init(rc) \
+  (G_GNUC_EXTENSION ({ \
+    G_STATIC_ASSERT (sizeof *(rc) == sizeof (gatomicrefcount)); \
+    (void) (0 ? *(rc) ^ *(rc) : 1); \
+    g_atomic_int_set ((rc), 1); \
+  }))
+
+# define g_atomic_ref_count_inc(rc) \
+  (G_GNUC_EXTENSION ({ \
+    G_STATIC_ASSERT (sizeof *(rc) == sizeof (gatomicrefcount)); \
+    (void) (0 ? *(rc) ^ *(rc) : 1); \
+    (void) (g_atomic_int_get (rc) == G_MAXINT ? 0 : g_atomic_int_inc ((rc))); \
+  }))
+
+# define g_atomic_ref_count_dec(rc) \
+  (G_GNUC_EXTENSION ({ \
+    G_STATIC_ASSERT (sizeof *(rc) == sizeof (gatomicrefcount)); \
+    (void) (0 ? *(rc) ^ *(rc) : 1); \
+    g_atomic_int_dec_and_test ((rc)); \
+  }))
+
+# define g_atomic_ref_count_compare(rc,val) \
+  (G_GNUC_EXTENSION ({ \
+    G_STATIC_ASSERT (sizeof *(rc) == sizeof (gatomicrefcount)); \
+    (void) (0 ? *(rc) ^ (val) : 1); \
+    (gboolean) (g_atomic_int_get (rc) == (val)); \
+  }))
+
+#endif /* __GNUC__ && G_DISABLE_CHECKS */
+
 G_END_DECLS
 
 #endif /* __GREFCOUNT_H__ */