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Re: [Xen-devel] [PATCH] x86/hpet: simplify hpet_get_channel()

>>> On 23.03.12 at 14:52, Keir Fraser <keir@xxxxxxx> wrote:
> On 23/03/2012 10:46, "Jan Beulich" <JBeulich@xxxxxxxx> wrote:
>>> Why is the following for-loop changed into do-while? It looks like it just
>>> makes the code longer, especially as you replace a % operator with
>>> open-coded equivalent for no reason I can see.
>> Simply because
>>     for ( i = next; i != next; ++i )
>> makes no sense.
>> Removing the % is an efficiency thing - the resulting code is not only
>> faster, but also smaller (presumably because of the special register
>> limitations div has).
> Does that matter? It's the last thing done before going into deep sleep.
> I suppose I don't mind that much, the whole thing just seems to make the C
> code longer.

Okay, let's forget about it then. (I could certainly make the code
shorter using a few comma expressions, but I don't think you'd
like that any better.)


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