Add compatibility support for older intel cpus

[urcu.git] / urcu / uatomic_arch_x86.h

diff --git a/urcu/uatomic_arch_x86.h b/urcu/uatomic_arch_x86.h
index 43de9e6be5543bb90811f373007b0fa88b6f1af6..fccea8e2d350321ebe9cbf4517a68866e4b5fa19 100644 (file)
--- a/urcu/uatomic_arch_x86.h
+++ b/urcu/uatomic_arch_x86.h
@@ -397,4 +397,20 @@ void _uatomic_dec(void *addr, int len)
 
 #define uatomic_dec(addr)      (_uatomic_dec((addr), sizeof(*(addr))))
 
+#if (BITS_PER_LONG == 64)
+#define URCU_CAS_AVAIL()       1
+#define compat_uatomic_cmpxchg(ptr, old, _new) uatomic_cmpxchg(ptr, old, _new)
+#else
+extern int __urcu_cas_avail;
+#define URCU_CAS_AVAIL()       __urcu_cas_avail
+
+extern unsigned long _compat_uatomic_cmpxchg(void *addr, unsigned long old,
+                             unsigned long _new, int len);
+
+#define compat_uatomic_cmpxchg(addr, old, _new)                                     \
+       ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), (unsigned long)(old),\
+                                               (unsigned long)(_new),       \
+                                               sizeof(*(addr))))
+#endif
+
 #endif /* _URCU_ARCH_UATOMIC_X86_H */