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andrepdyesterday at 7:10 PM1 replyview on HN

> Unums have proven difficult to build efficient HW implementations for

Valid point, but not quite true anymore. It comes down basically to the latency of count_leading_ones/zeros for decoding the regime, on which everything else depends. But work has been done in the past ~2ish years and we can have posit units with lower latency than FP units of the same width! https://arxiv.org/abs/2603.01615

> IEEE floats have a few warts like any other 1980s standard, but they're a fantastic design.

Hmm I don't know if I would call it a fantastic design x) The "standard" is less a standard than a rough formalisation of a specific FPU design from back in the 1980s, and that design was in turn not really the product of a forward thinking visionary but something to fit the technical and business constraints of that specific piece of hardware.

It has more than a few warts and we can probably do much better nowadays. That's not really a diss on IEEE floats or their designers, it's just a matter of fact (which honestly applies to very many things which are 40 years old, let alone those designed under the constraints of IEEE754).


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AlotOfReadingyesterday at 9:05 PM

I'm sure you're much more knowledgeable about this than I am, but that's kind of my point. A month old preprint is the first thing to compare to implementations of a mildly evolved, warty old standard from 40 years ago. I consider that fantastic.

Thanks for the paper though. Looking forward to reading it more closely when I have time.

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