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From:   John Yates <john@yates-sheets.org>
Date:   Mon, 6 Jan 2020 10:47:50 -0500
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On Mon, Jan 6, 2020 at 10:20 AM Toke Høiland-Jørgensen <toke@redhat.com> wrote:
> Or do a middle ground thing where we use 32-bit arithmetic
> for the per-station weights, but go to 64-bit for the weight sum? I
> don't really have a good grip on how much of a performance impact we're
> talking about here, so I'm not sure which I prefer...

Double width accumulation is very common in many applications.
Double width addition and comparison are _much_ cheaper than
double width multiplication and division.

/john