[PATCH v3 1/2] include/qemu/int128.h: introduce bswap128s

[matheus . ferst]

From: Matheus Ferst <matheus.ferst@eldorado.org.br>

Changes the current bswap128 implementation to use __builtin_bswap128
when available, adds a bswap128 implementation for !CONFIG_INT128
builds, and introduces bswap128s based on bswap128.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
---
 include/qemu/int128.h | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/include/qemu/int128.h b/include/qemu/int128.h
index e36c6e6db5..aa7a532727 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 */
@@ -342,5 +346,16 @@ 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 */
-- 
2.25.1