svn commit: r252032 - head/sys/amd64/include

[Lawrence Stewart]

Hi Kostik,

On 06/21/13 00:30, Konstantin Belousov wrote:
> Author: kib
> Date: Thu Jun 20 14:30:04 2013
> New Revision: 252032
> URL: http://svnweb.freebsd.org/changeset/base/252032
> 
> Log:
>   Allow immediate operand.
>   
>   Sponsored by:	The FreeBSD Foundation
> 
> Modified:
>   head/sys/amd64/include/counter.h
> 
> Modified: head/sys/amd64/include/counter.h
> ==============================================================================
> --- head/sys/amd64/include/counter.h	Thu Jun 20 14:20:03 2013	(r252031)
> +++ head/sys/amd64/include/counter.h	Thu Jun 20 14:30:04 2013	(r252032)
> @@ -44,7 +44,7 @@ counter_u64_add(counter_u64_t c, int64_t
>  
>  	__asm __volatile("addq\t%1,%%gs:(%0)"
>  	    :
> -	    : "r" ((char *)c - (char *)&__pcpu[0]), "r" (inc)
> +	    : "r" ((char *)c - (char *)&__pcpu[0]), "ri" (inc)
>  	    : "memory", "cc");
>  }

For mere mortals like myself, a verbose explanation of what this does,
why it's necessary and what problem(s) it solves (if any) would be most
helpful :)

Cheers,
Lawrence