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Re: High level language for writing [unum] Forth

From Jan Coombs <jenfhaomndgfwutc@murmic.plus.com>
Newsgroups comp.lang.forth
Subject Re: High level language for writing [unum] Forth
Date 2017-04-23 09:33 +0100
Organization A noiseless patient Spider
Message-ID <20170423093340.0f189667@t530.lan> (permalink)
References (16 earlier) <a5e39d07-7ae8-45d4-b29c-7521d67aad66@googlegroups.com> <20170422165131.255d9f22@t530.lan> <87shl0yyah.fsf@nightsong.com> <20170422225911.1ea7968b@t530.lan> <87k26bzyo1.fsf@nightsong.com>

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On Sat, 22 Apr 2017 18:43:26 -0700
Paul Rubin <no.email@nospam.invalid> wrote:

> Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> writes:
> > Who is there bold enough, willing to step outside the cage,
> > and be worthy of congratulions?
> 
> John McCarthy?  Again, you're reinventing Lisp from 60 years
> ago.

Much as I'd like to agree with you, this is unlikely. My focus
is on hardware development. This is because the Unum data type
is incompatible with current float hardware, (see below) so
efficient modelling of Unums is not possible, and adding a
Unum library to any language nearly pointless. 

As for Forth, it would be simplified:  No need for a separate
float stack, automatic promotion of integers to exact floats[1]
or BigNum when arithmetic demands it. Double numbers redundant. 
Significant compression of Flags and small integers. 


The IEE754 float has the leftmost bit of the mantissa hidden,
and the rest in a fixed length field. In this field the bits
toward the left contain data, and the rest junk. 

In a Unum[2] mantissa field, all bits contain valid data. If
padding is needed to match field allocation granularity it must
be a sign bit extension, at the left end. 

So, the mantissa of an IEE754 float is left aligned, and that of
a Unum is right aligned. This is why the Unum data type cannot
be efficiently modelled in current processor hardware. 

This difference is what allows a Unum processor to produce
correct results[1] and use less power.  Correct because no junk
is stored in the mantissa. An anticipated 50% power saving
because of not having to move this junk to and from main
memory.[3]


Is this really an opportunity to support simpler programming
languages with greater computational efficiency, or a magical
fairy tale from the dark side, or perhaps both?

Jan Coombs
--   

[1] The Unum mantissa is extended one bit past the ULP, this
'Uncertainty bit' declares whether the mantissa is exact, or is
the base of an open interval one ULP wide. Unum computation
results are correct, even where this requires declaring the
bounds of uncertainty to achieve this. (Unlike IEE754)

[2] That is Unum type 1.  In Unum type 2 reduced benefits
are anticipated because the binary format used is of fixed
length.

[3] "The End of Error" pg6: Energy cost of 64b float read from
reg and MAC operation is 70pJ, the cost of fetching 64b from
DRAM is 4200pJ, 60 times more! (on 2010 era hardware)  Unum data
is inherently compressed. (at the cost of on-chip complexity)

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Thread

High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-19 18:32 -0500
  Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-20 00:24 +0000
    Re: High level language for writing Forth "Elizabeth D. Rather" <erather@forth.com> - 2017-04-19 14:42 -1000
      Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-19 20:33 -0500
        Re: High level language for writing Forth "Elizabeth D. Rather" <erather@forth.com> - 2017-04-19 16:21 -1000
        Re: High level language for writing Forth Paul Rubin <no.email@nospam.invalid> - 2017-04-19 19:41 -0700
          Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-19 23:28 -0500
      Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-20 17:02 +0000
        Re: High level language for writing Forth "Elizabeth D. Rather" <erather@forth.com> - 2017-04-20 09:48 -1000
          Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-21 09:42 +0000
            Re: High level language for writing Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-04-21 09:07 -0500
              Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-21 17:04 +0100
                Re: High level language for writing Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-04-21 11:17 -0500
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-21 17:36 +0100
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-21 20:32 +0000
                Re: High level language for writing Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-04-21 15:35 -0500
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-21 20:39 +0000
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-21 22:47 +0100
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-21 20:29 +0000
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-21 22:45 +0100
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-22 04:49 +0000
                Re: High level language for writing Forth Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2017-04-22 10:54 +0100
                Re: High level language for writing Forth Mark Wills <markwills1970@gmail.com> - 2017-04-22 03:04 -0700
                Re: High level language for writing Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-04-22 05:12 -0500
                Re: High level language for writing Forth lehs <skydda.barnen@gmail.com> - 2017-04-22 04:30 -0700
                Re: High level language for writing Forth Mark Wills <markwills1970@gmail.com> - 2017-04-22 05:00 -0700
                Re: High level language for writing Forth lehs <skydda.barnen@gmail.com> - 2017-04-22 05:40 -0700
                Re: High level language for writing [unum] Forth Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2017-04-22 16:51 +0100
                Re: High level language for writing [unum] Forth Paul Rubin <no.email@nospam.invalid> - 2017-04-22 13:36 -0700
                Re: High level language for writing [unum] Forth Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2017-04-22 22:59 +0100
                Re: High level language for writing [unum] Forth Paul Rubin <no.email@nospam.invalid> - 2017-04-22 18:43 -0700
                Re: High level language for writing [unum] Forth Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2017-04-23 09:33 +0100
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-22 11:23 -0500
                Re: High level language for writing Forth Mark Wills <markwills1970@gmail.com> - 2017-04-22 04:59 -0700
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-29 03:05 +0000
                Re: High level language for writing Forth Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2017-04-29 09:35 +0100
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-22 12:56 +0100
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-29 03:08 +0000
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-29 09:46 +0100
                Re: High level language for writing Forth lehs <skydda.barnen@gmail.com> - 2017-04-29 02:45 -0700
                Re: High level language for writing Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-04-29 13:44 +0000
                Re: High level language for writing Forth lehs <skydda.barnen@gmail.com> - 2017-04-29 07:00 -0700
                Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-04-29 07:31 -0700
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-29 16:38 +0100
                Re: High level language for writing Forth Joel Rees <joel.rees@gmail.com> - 2017-04-29 04:10 -0700
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-29 11:35 +0000
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-29 16:33 +0100
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-05 15:24 +0000
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-05-05 20:16 +0100
                Re: High level language for writing Forth Lars Brinkhoff <lars.spam@nocrew.org> - 2017-05-05 22:06 +0200
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-05-05 21:45 +0100
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-05-05 21:54 +0100
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-06 10:06 +0000
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-05-06 13:09 +0100
                Re: High level language for writing Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-06 11:04 +0000
              Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-21 20:28 +0000
                Re: High level language for writing Forth "Elizabeth D. Rather" <erather@forth.com> - 2017-04-21 12:27 -1000
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-22 04:55 +0000
                Re: High level language for writing Forth Coos Haak <htrofhc@gmail.com> - 2017-04-22 02:01 +0200
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-22 04:58 +0000
                Re: High level language for writing Forth Paul Rubin <no.email@nospam.invalid> - 2017-04-21 23:41 -0700
                Re: High level language for writing Forth Coos Haak <htrofhc@gmail.com> - 2017-04-22 22:15 +0200
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-06 13:28 +0000
                Re: High level language for writing Forth Joel Rees <joel.rees@gmail.com> - 2017-04-27 02:51 -0700
                Re: High level language for writing Forth Lars Brinkhoff <lars.spam@nocrew.org> - 2017-04-27 12:09 +0200
                Re: High level language for writing Forth Joel Rees <joel.rees@gmail.com> - 2017-04-29 02:48 -0700
                Re: High level language for writing Forth "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-04-29 03:09 +0000
    Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-19 20:11 -0500
  Re: High level language for writing Forth Paul Rubin <no.email@nospam.invalid> - 2017-04-19 19:34 -0700
    Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-19 23:22 -0500
      Re: High level language for writing Forth Paul Rubin <no.email@nospam.invalid> - 2017-04-19 21:35 -0700
        Re: High level language for writing Forth Melzzzzz <Melzzzzz@zzzzz.com> - 2017-04-20 05:12 +0000
        Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-20 01:15 -0500
          Re: High level language for writing Forth Paul Rubin <no.email@nospam.invalid> - 2017-04-19 23:25 -0700
          Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-21 23:12 -0500
            Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-04-21 21:53 -0700
              Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-22 00:42 -0500
                Re: High level language for writing Forth Paul Rubin <no.email@nospam.invalid> - 2017-04-21 23:44 -0700
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-22 03:08 -0500
                Re: High level language for writing Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-04-22 04:39 -0500
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-22 12:37 +0100
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-22 11:33 -0500
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-22 14:10 -0500
                Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-04-22 15:01 -0700
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-22 23:38 +0100
                Re: High level language for writing Forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-04-22 16:30 -0700
                Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-04-22 18:01 -0700
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-23 09:25 +0100
                Re: High level language for writing Forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-04-23 06:32 -0700
                Re: High level language for writing Forth Julian Fondren <julian.fondren@gmail.com> - 2017-04-23 07:36 -0700
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-24 14:32 +0100
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-22 18:19 -0500
                Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-04-22 18:05 -0700
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-22 21:51 -0500
                Re: High level language for writing Forth Ron Aaron <rambamist@gmail.com> - 2017-04-23 06:54 +0300
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-23 09:16 +0100
                Re: High level language for writing Forth Ron Aaron <rambamist@gmail.com> - 2017-04-23 18:41 +0300
                Re: High level language for writing Forth Alex <alex@rivadpm.com> - 2017-04-24 14:35 +0100
                Re: High level language for writing Forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-04-23 06:15 -0700
              Re: High level language for writing Forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-04-22 08:04 -0700
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-22 11:44 -0500
                Re: High level language for writing Forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-04-22 12:16 -0700
              Re: High level language for writing Forth Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> - 2017-04-22 22:52 -0400
      Re: High level language for writing Forth Ron Aaron <rambamist@gmail.com> - 2017-04-20 07:49 +0300
    Re: High level language for writing Forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-04-20 19:47 +0200
      Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-20 15:19 -0500
  Re: High level language for writing Forth Lars Brinkhoff <lars.spam@nocrew.org> - 2017-04-20 08:06 +0200
  Re: High level language for writing Forth Ilya Tarasov <ilya74.tarasov@gmail.com> - 2017-04-20 04:35 -0700
  Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-04-25 17:03 -0500
    Re: High level language for writing Forth minforth@arcor.de - 2017-04-26 01:58 -0700
  Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-05-13 17:36 -0500
    Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-05-13 18:37 -0700
      Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-05-13 20:52 -0500
        Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-05-13 19:25 -0700
          Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-05-15 12:44 -0700
            Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-05-15 17:27 -0500
              Re: High level language for writing Forth hughaguilar96@gmail.com - 2017-05-15 19:43 -0700
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-05-15 23:55 -0500
                Re: High level language for writing Forth Mark Wills <markwills1970@gmail.com> - 2017-05-16 01:59 -0700
                Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-05-15 23:58 -0500
    Re: High level language for writing Forth Joel Rees <joel.rees@gmail.com> - 2017-05-15 07:00 -0700
      Re: High level language for writing Forth Cecil Bayona <cbayona@cbayona.com> - 2017-05-15 12:05 -0500

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