From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:56924) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UL15d-0004Ad-Di for qemu-devel@nongnu.org; Wed, 27 Mar 2013 20:53:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UL15a-0002d1-5a for qemu-devel@nongnu.org; Wed, 27 Mar 2013 20:53:13 -0400 Sender: Richard Henderson Message-ID: <51539468.6060301@twiddle.net> Date: Wed, 27 Mar 2013 17:52:56 -0700 From: Richard Henderson MIME-Version: 1.0 References: <1364410030-24008-1-git-send-email-rth@twiddle.net> <515383E2.7010408@suse.de> In-Reply-To: <515383E2.7010408@suse.de> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH] vmxnet: Don't use bswap_64 for constants List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?ISO-8859-15?Q?Andreas_F=E4rber?= Cc: qemu-trivial@nongnu.org, qemu-devel@nongnu.org On 2013-03-27 16:42, Andreas Färber wrote: > Am 27.03.2013 19:47, schrieb Richard Henderson: >> This macro is used in the context of defining enum values. >> We can't use a function call in that case. >> >> Cc: qemu-trivial@nongnu.org >> Signed-off-by: Richard Henderson >> --- >> hw/vmxnet3.h | 10 +++++++++- >> 1 file changed, 9 insertions(+), 1 deletion(-) >> >> diff --git a/hw/vmxnet3.h b/hw/vmxnet3.h >> index 7db0c8f..cd9ac85 100644 >> --- a/hw/vmxnet3.h >> +++ b/hw/vmxnet3.h >> @@ -37,7 +37,15 @@ >> #define __packed QEMU_PACKED >> >> #if defined(HOST_WORDS_BIGENDIAN) >> -#define const_cpu_to_le64(x) bswap_64(x) >> +#define const_cpu_to_le64(x) \ >> + (((x & 0x00000000000000ffULL) << 56) | \ >> + ((x & 0x000000000000ff00ULL) << 40) | \ >> + ((x & 0x0000000000ff0000ULL) << 24) | \ >> + ((x & 0x00000000ff000000ULL) << 8) | \ >> + ((x & 0x000000ff00000000ULL) >> 8) | \ >> + ((x & 0x0000ff0000000000ULL) >> 24) | \ >> + ((x & 0x00ff000000000000ULL) >> 40) | \ >> + ((x & 0xff00000000000000ULL) >> 56)) > > Being a macro, shouldn't this better use (x) for operator precedence? It doesn't matter for this usage. Nor, according to other threads that appeared on the list today, is this the right fix, since the bswap itself turns out to be bogus. Myself, I never tested the driver code, just fixed the compile error. r~