Re: [PATCH] __div64_32: implement division by multiplication for 32-bit arches

From: Måns Rullgård
Date: Fri Oct 30 2015 - 13:45:35 EST


Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> writes:

> On Fri, 30 Oct 2015, Alexey Brodkin wrote:
>
>> Hi Nicolas,
>>
>> On Fri, 2015-10-30 at 11:17 -0400, Nicolas Pitre wrote:
>> > On Fri, 30 Oct 2015, Måns Rullgård wrote:
>> >
>> > > Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> writes:
>> > >
>> > > > OK... I was intrigued, so I adapted my ARM code to the generic case,
>> > > > including the overflow avoidance optimizations. Please have look and
>> > > > tell me how this works for you.
>> > > >
>> > > > If this patch is accepted upstream, then it could be possible to
>> > > > abstract only the actual multiplication part with some architecture
>> > > > specific assembly.
>> > >
>> > > Good idea.
>> >
>> > Could you please provide a reviewed-by or acked-by tag?
>>
>> Sure!
>>
>> Acked-by: Alexey Brodkin <abrodkin@xxxxxxxxxxxx>
>>
>> BTW I thought about that optimization a bit more and now I think
>> we may even skip addition of arch-specific assembly insertions.
>
> I'm going to do it anyway given that I already have it for ARM. It'll
> be opt-in, so if your arch doesn't provide it then the current C
> implementation will be used by default.

Great. I'll try it out on MIPS once you've posted the patch.

--
Måns Rullgård
mans@xxxxxxxxx
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