+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
+#define COMPILER_HAVE_SHORT_MEM_OPERAND
+#endif
+
+/*
+ * MEMOP assembler operand rules:
+ * - op refer to MEMOP_IN operand
+ * - MEMOP_IN can expand to more than a single operand. Use it at the end of
+ * operand list only.
+ */
+
+#ifdef COMPILER_HAVE_SHORT_MEM_OPERAND
+
+#define MEMOP_OUT(addr) "=Q" (*(addr))
+#define MEMOP_IN(addr) "Q" (*(addr))
+#define MEMOP_REF(op) #op /* op refer to MEMOP_IN operand */
+
+#else /* !COMPILER_HAVE_SHORT_MEM_OPERAND */
+
+#define MEMOP_OUT(addr) "=m" (*(addr))
+#define MEMOP_IN(addr) "a" (addr), "m" (*(addr))
+#define MEMOP_REF(op) "0(" #op ")" /* op refer to MEMOP_IN operand */
+
+#endif /* !COMPILER_HAVE_SHORT_MEM_OPERAND */
+
+struct __uatomic_dummy {
+ unsigned long v[10];
+};
+#define __hp(x) ((struct __uatomic_dummy *)(x))
+