From: "Philippe Mathieu-Daudé" <philmd@redhat.com>
To: qemu-devel@nongnu.org
Cc: "Fam Zheng" <fam@euphon.net>,
"Alex Bennée" <alex.bennee@linaro.org>,
"Kamil Rytarowski" <kamil@netbsd.org>,
"Richard Henderson" <richard.henderson@linaro.org>,
"Philippe Mathieu-Daudé" <philmd@redhat.com>
Subject: [PATCH v2 2/8] qemu/bswap: Replace bswapXX() by compiler __builtin_bswap()
Date: Mon, 28 Sep 2020 15:19:28 +0200 [thread overview]
Message-ID: <20200928131934.739451-3-philmd@redhat.com> (raw)
In-Reply-To: <20200928131934.739451-1-philmd@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.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
include/qemu/bswap.h | 33 +++++++--------------------------
1 file changed, 7 insertions(+), 26 deletions(-)
diff --git a/include/qemu/bswap.h b/include/qemu/bswap.h
index 8b01c38040c..41131d3d76e 100644
--- a/include/qemu/bswap.h
+++ b/include/qemu/bswap.h
@@ -27,32 +27,13 @@ static inline uint64_t bswap64(uint64_t x)
{
return bswap_64(x);
}
-# else
-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));
-}
+#else
+#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 /* ! CONFIG_MACHINE_BSWAP_H */
static inline void bswap16s(uint16_t *s)
--
2.26.2
next prev parent reply other threads:[~2020-09-28 13:48 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-28 13:19 [PATCH v2 0/8] qemu/bswap: Use compiler __builtin_bswap() Philippe Mathieu-Daudé
2020-09-28 13:19 ` [PATCH v2 1/8] qemu/bswap: Remove unused qemu_bswap_len() Philippe Mathieu-Daudé
2020-09-28 13:19 ` Philippe Mathieu-Daudé [this message]
2020-09-28 13:19 ` [PATCH v2 3/8] qemu/bswap: Replace bswapXXs() by compiler __builtin_bswap() Philippe Mathieu-Daudé
2020-09-28 17:29 ` Thomas Huth
2020-09-28 13:19 ` [PATCH v2 4/8] qemu/bswap: Remove <byteswap.h> dependency Philippe Mathieu-Daudé
2020-09-28 13:19 ` [PATCH v2 5/8] qemu/bswap: Use compiler __builtin_bswap() on Haiku Philippe Mathieu-Daudé
2020-09-28 14:09 ` David CARLIER
2020-09-28 14:13 ` Daniel P. Berrangé
2020-09-28 14:18 ` Philippe Mathieu-Daudé
2020-10-19 11:00 ` Philippe Mathieu-Daudé
2020-09-28 15:00 ` David CARLIER
2020-09-28 17:29 ` Thomas Huth
2020-09-28 13:19 ` [PATCH v2 6/8] qemu/bswap: Use compiler __builtin_bswap() on FreeBSD Philippe Mathieu-Daudé
2020-09-28 17:32 ` Thomas Huth
2020-09-28 17:57 ` Philippe Mathieu-Daudé
2020-09-28 17:58 ` Philippe Mathieu-Daudé
2020-09-28 21:16 ` Ed Maste
2020-09-28 13:19 ` [PATCH v2 7/8] qemu/bswap: Use compiler __builtin_bswap() on NetBSD Philippe Mathieu-Daudé
2020-09-28 21:51 ` Kamil Rytarowski
2020-09-29 8:58 ` Peter Maydell
2020-09-29 14:06 ` Kamil Rytarowski
2020-09-28 13:19 ` [RFC PATCH v2 8/8] tests/vm: Add Haiku test based on their vagrant images Philippe Mathieu-Daudé
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