[atomic] Fallback to libatomic-ops-dev

Use libatomic-ops-dev in preference to mutex-based atomics, if we do not
have the builtin atomic intrinsics available.

1 files changed, 36 insertions, 5 deletions

diff --git a/src/cairo-atomic-private.h b/src/cairo-atomic-private.h
index bf79b7a99..d2583a17a 100644
--- a/src/cairo-atomic-private.h
+++ b/src/cairo-atomic-private.h
@@ -57,6 +57,9 @@ CAIRO_BEGIN_DECLS
 
 typedef int cairo_atomic_int_t;
 
+# define _cairo_atomic_int_get(x) (*x)
+# define _cairo_atomic_int_set(x, value) ((*x) = value)
+
 # define _cairo_atomic_int_inc(x) ((void) __sync_fetch_and_add(x, 1))
 # define _cairo_atomic_int_dec_and_test(x) (__sync_fetch_and_add(x, -1) == 1)
 # define _cairo_atomic_int_cmpxchg(x, oldv, newv) __sync_val_compare_and_swap (x, oldv, newv)
@@ -76,6 +79,35 @@ typedef long long cairo_atomic_intptr_t;
 
 #endif
 
+#if HAVE_LIB_ATOMIC_OPS
+#include <atomic_ops.h>
+
+#define HAS_ATOMIC_OPS 1
+
+typedef  AO_t cairo_atomic_int_t;
+
+# define _cairo_atomic_int_get(x) (AO_load_full (x))
+# define _cairo_atomic_int_set(x, value) (AO_store_full (x))
+
+# define _cairo_atomic_int_inc(x) ((void) AO_fetch_and_add1_full(x))
+# define _cairo_atomic_int_dec_and_test(x) (AO_fetch_and_sub1_full(x) == 1)
+# define _cairo_atomic_int_cmpxchg(x, oldv, newv) ((cairo_atomic_int_t) AO_compare_and_swap_full(x, oldv, newv))
+
+#if SIZEOF_VOID_P==SIZEOF_INT
+typedef unsigned int cairo_atomic_intptr_t;
+#elif SIZEOF_VOID_P==SIZEOF_LONG
+typedef unsigned long cairo_atomic_intptr_t;
+#elif SIZEOF_VOID_P==SIZEOF_LONG_LONG
+typedef unsigned long long cairo_atomic_intptr_t;
+#else
+#error No matching integer pointer type
+#endif
+
+# define _cairo_atomic_ptr_cmpxchg(x, oldv, newv) \
+    (void*) (cairo_atomic_intptr_t) _cairo_atomic_int_cmpxchg ((cairo_atomic_intptr_t*)(x), (cairo_atomic_intptr_t)oldv, (cairo_atomic_intptr_t)newv)
+
+#endif
+
 
 #ifndef HAS_ATOMIC_OPS
 
@@ -93,9 +125,6 @@ _cairo_atomic_int_cmpxchg (int *x, int oldv, int newv);
 cairo_private void *
 _cairo_atomic_ptr_cmpxchg (void **x, void *oldv, void *newv);
 
-#endif
-
-
 #ifdef ATOMIC_OP_NEEDS_MEMORY_BARRIER
 
 # include "cairo-compiler-private.h"
@@ -113,14 +142,16 @@ _cairo_atomic_int_set (int *x, int value);
 
 #endif
 
+#endif
+
 #define _cairo_atomic_uint_get(x) _cairo_atomic_int_get(x)
 #define _cairo_atomic_uint_cmpxchg(x, oldv, newv) \
-    _cairo_atomic_int_cmpxchg((int *)x, oldv, newv)
+    _cairo_atomic_int_cmpxchg((cairo_atomic_int_t *)x, oldv, newv)
 
 #define _cairo_status_set_error(status, err) do { \
     /* hide compiler warnings about cairo_status_t != int (gcc treats its as \
      * an unsigned integer instead, and about ignoring the return value. */  \
-    int ret__ = _cairo_atomic_int_cmpxchg ((int *) status, CAIRO_STATUS_SUCCESS, err); \
+    int ret__ = _cairo_atomic_int_cmpxchg ((cairo_atomic_int_t *) status, CAIRO_STATUS_SUCCESS, err); \
     (void) ret__; \
 } while (0)