Date: Sat, 28 Nov 1998 00:59:01 -0500 (EST) From: "John S. Dyson" <dyson@iquest.net> To: bde@zeta.org.au (Bruce Evans) Cc: current@FreeBSD.ORG, dyson@iquest.net Subject: Re: Fix for incorrect clobbers in asm's Message-ID: <199811280559.AAA04288@y.dyson.net> In-Reply-To: <199811280526.QAA22443@godzilla.zeta.org.au> from Bruce Evans at "Nov 28, 98 04:26:35 pm"
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Bruce Evans said:
>
> Rewritten using constraints:
>
> __asm __volatile("cld; rep; insb"
> : "=D" (addr), "=c" (cnt)
> : "0" (addr), "1" (cnt), "d" (port)
> : "memory");
>
> This discards the output operands in the input variables to avoid extra
> local variables. This is harmless because the input variables are dead,
> and more natural because it is normal for pointers to be incremented and
> counts to be decremented.
>
Yes, your specific approach is better. However, the incorrect clobbers
do need to be fixed, or compiling kernels with egcs will be forever a pain...
--
John | Never try to teach a pig to sing,
dyson@iquest.net | it makes one look stupid
jdyson@nc.com | and it irritates the pig.
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