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Date: Fri, 16 Aug 2013 08:27:06 -0700
From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] [PATCH v2] exec: Fix non-power-of-2 sized accesses
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To: Alex Williamson <alex.williamson@redhat.com>
Cc: lersek@redhat.com, qemu-devel@nongnu.org, qemu-stable@nongnu.org

On 08/16/2013 05:50 AM, Alex Williamson wrote:
> +    /* Size must be a power of 2 */
> +    if (l & (l - 1)) {
> +        while (l & (access_size_max - 1)) {
> +            access_size_max >>= 1;
> +        }
> +    }
> +

Why the loop at all?  x & -x extracts the lsb of x.


r~