Add atomic operation support for OS X.

jemalloc/include/jemalloc/internal/atomic.h

@@ -49,6 +49,20 @@ atomic_sub_uint64(uint64_t *p, uint64_t x)
 
 	return (__sync_sub_and_fetch(p, x));
 }
+#elif (defined(JEMALLOC_OSATOMIC))
+JEMALLOC_INLINE uint64_t
+atomic_add_uint64(uint64_t *p, uint64_t x)
+{
+
+	return (OSAtomicAdd64((int64_t)x, (int64_t *)p));
+}
+
+JEMALLOC_INLINE uint64_t
+atomic_sub_uint64(uint64_t *p, uint64_t x)
+{
+
+	return (OSAtomicAdd64(-((int64_t)x), (int64_t *)p));
+}
 #else
 #  error "Missing implementation for 64-bit atomic operations"
 #endif
@@ -68,6 +82,20 @@ atomic_sub_uint32(uint32_t *p, uint32_t x)
 
 	return (__sync_sub_and_fetch(p, x));
 }
+#elif (defined(JEMALLOC_OSATOMIC))
+JEMALLOC_INLINE uint32_t
+atomic_add_uint32(uint32_t *p, uint32_t x)
+{
+
+	return (OSAtomicAdd32((int32_t)x, (int32_t *)p));
+}
+
+JEMALLOC_INLINE uint32_t
+atomic_sub_uint32(uint32_t *p, uint32_t x)
+{
+
+	return (OSAtomicAdd32(-((int32_t)x), (int32_t *)p));
+}
 #else
 #  error "Missing implementation for 32-bit atomic operations"
 #endif

jemalloc/include/jemalloc/internal/jemalloc_internal.h.in

@@ -33,6 +33,10 @@
 #define	JEMALLOC_MANGLE
 #include "../jemalloc@install_suffix@.h"
 
+#ifdef JEMALLOC_OSATOMIC
+#include <libkern/OSAtomic.h>
+#endif
+
 #ifdef JEMALLOC_ZONE
 #include <mach/mach_error.h>
 #include <mach/mach_init.h>

jemalloc/include/jemalloc/jemalloc_defs.h.in

@@ -24,6 +24,12 @@
  */
 #undef CPU_SPINWAIT
 
+/*
+ * Defined if OSAtomic*() functions are available, as provided by Darwin, and
+ * documented in the atomic(3) manual page.
+ */
+#undef JEMALLOC_OSATOMIC
+
 /* Defined if __attribute__((...)) syntax is supported. */
 #undef JEMALLOC_HAVE_ATTR
 #ifdef JEMALLOC_HAVE_ATTR