From: Philippe Mathieu-Daudé <phi...@redhat.com>
Use the compiler built-in function to byte swap values,
as the compiler is clever and will fold constants.
Suggested-by: Richard Henderson <richard.hender...@linaro.org>
Reviewed-by: Richard Henderson <richard.hender...@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
---
include/qemu/bswap.h | 31 ++++++-------------------------
1 file changed, 6 insertions(+), 25 deletions(-)
diff --git a/include/qemu/bswap.h b/include/qemu/bswap.h
index 346d05f2aa..ca2b4c3f15 100644
--- a/include/qemu/bswap.h
+++ b/include/qemu/bswap.h
@@ -37,31 +37,12 @@ static inline uint64_t bswap64(uint64_t x)
#endif
#ifdef BSWAP_FROM_FALLBACKS
-static inline uint16_t bswap16(uint16_t x)
-{
- return (((x & 0x00ff) << 8) |
- ((x & 0xff00) >> 8));
-}
-
-static inline uint32_t bswap32(uint32_t x)
-{
- return (((x & 0x000000ffU) << 24) |
- ((x & 0x0000ff00U) << 8) |
- ((x & 0x00ff0000U) >> 8) |
- ((x & 0xff000000U) >> 24));
-}
-
-static inline uint64_t bswap64(uint64_t x)
-{
- return (((x & 0x00000000000000ffULL) << 56) |
- ((x & 0x000000000000ff00ULL) << 40) |
- ((x & 0x0000000000ff0000ULL) << 24) |
- ((x & 0x00000000ff000000ULL) << 8) |
- ((x & 0x000000ff00000000ULL) >> 8) |
- ((x & 0x0000ff0000000000ULL) >> 24) |
- ((x & 0x00ff000000000000ULL) >> 40) |
- ((x & 0xff00000000000000ULL) >> 56));
-}
+#undef bswap16
+#define bswap16(_x) __builtin_bswap16(_x)
+#undef bswap32
+#define bswap32(_x) __builtin_bswap32(_x)
+#undef bswap64
+#define bswap64(_x) __builtin_bswap64(_x)
#endif
#undef BSWAP_FROM_BYTESWAP
--
2.38.1
