[Cfp-interest 2717] Re: WG14 IEEE 754-C binding meeting minutes 2023/01/31

[Vincent Lefevre]

On 2023-02-27 15:52:20 -0800, Jim Thomas wrote:
> Good point. Would a definition requiring just inclusion work? That
> would be: type A is wider than type B iff the values of A are a
> superset of the values of B. Then double-double would be wider than
> binary64, even though binary64 has the greater exponent range (for
> full precision of the types). Are there places where use of the
> wider type terminology depends on wider exponent range?

I think that the inclusion would work. But the definition needs to be
unambiguous. For instance, it needs to be clear whether the case where
one format has unsigned zeros while the other format has signed zeros
is accepted, in particular, whether { 0 } is included in { +0, −0 }.
Ditto for NaN and their payloads: does the inclusion of the payloads
matter?

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Vincent Lefèvre <vincent at vinc17.net> - Web: <https://www.vinc17.net/>
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