diff --git a/include/qemu/int128.h b/include/qemu/int128.h
index 17436d851d..2ac0746426 100644
--- a/include/qemu/int128.h
+++ b/include/qemu/int128.h
@@ -1,9 +1,9 @@
 #ifndef INT128_H
 #define INT128_H
 
-#ifdef CONFIG_INT128
 #include "qemu/bswap.h"
 
+#ifdef CONFIG_INT128
 typedef __int128_t Int128;
 
 static inline Int128 int128_make64(uint64_t a)
@@ -155,7 +155,11 @@ static inline void int128_subfrom(Int128 *a, Int128 b)
 
 static inline Int128 bswap128(Int128 a)
 {
+#if __has_builtin(__builtin_bswap128)
+    return __builtin_bswap128(a);
+#else
     return int128_make128(bswap64(int128_gethi(a)), bswap64(int128_getlo(a)));
+#endif
 }
 
 #else /* !CONFIG_INT128 */
@@ -350,5 +354,16 @@ static inline void int128_subfrom(Int128 *a, Int128 b)
     *a = int128_sub(*a, b);
 }
 
+static inline Int128 bswap128(Int128 a)
+{
+    return int128_make128(bswap64(a.hi), bswap64(a.lo));
+}
+
 #endif /* CONFIG_INT128 */
+
+static inline void bswap128s(Int128 *s)
+{
+    *s = bswap128(*s);
+}
+
 #endif /* INT128_H */