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From: mitchalsup@aol.com (MitchAlsup1)
Newsgroups: comp.arch
Subject: Re: Making Lemonade (Floating-point format changes)
Date: Sun, 12 May 2024 20:12:22 +0000
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John Savard wrote:

> On Sun, 12 May 2024 13:46:28 -0000 (UTC), Thomas Koenig
> <tkoenig@netcologne.de> wrote:
>>John Savard <quadibloc@servername.invalid> schrieb:
>>
>>> I have instead defined a 256-bit format for floats which does not have
>>> a hidden first bit, which looks like the old temporary reals, except
>>> that the exponent field is one bit wider.
>>
>>Why not the IEEE binary256 (interchange) format?
>>
>>https://en.wikipedia.org/wiki/Octuple-precision_floating-point_format

> Oh, drat. I had not realized that they had also defined this.

> Now that means I need to make the exponent field  in my internal
> format larger, define a 512-bit floating point number which is in the
> internal format, so that it can be unnormalized, and a 1024-bit
> doubled-up float... instead of what I just did!

> The enlarged exponent field won't make the internal form of the
> 128-bit float go over 160 bits, so register allocation for th at won't
> change... but now I will have to figure out a scheme of register
> allocation applicable to the 256-bit floats!

> I am not amused.

Question:: why are you all so gung-ho on having a format without a hidden bit.
It is trivially easy to reconstruct::

     h = expon != 0;

Taking little time of even gates; and is something you HAVE to do anyway.

> John Savard