Re: Forth-94 vs. Forth-2012 FP data (long)

From	anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups	comp.lang.forth
Subject	Re: Forth-94 vs. Forth-2012 FP data (long)
Date	2017-05-15 15:03 +0000
Organization	Institut fuer Computersprachen, Technische Universitaet Wien
Message-ID	<2017May15.170302@mips.complang.tuwien.ac.at> (permalink)
References	<2017May13.093451@mips.complang.tuwien.ac.at> <ofb87j$7hq$1@gioia.aioe.org>

Show all headers | View raw

"HAA" <someone@microsoft.com> writes:
>How about this for an 'empirical' check.  Write a real-world application
>for which hardware f/p is not available.  Implement it using combined
>and separate stack f/p.  Compare the performance and memory used.
>Expect to see much difference?  Neither do I.

I didn't expect it for the matrix multiplication case, but I actually
measured it and found a difference, and found an explanation for the
difference.  Maybe you should actually read the whole posting before
replying.

>200x did not - nor can it - demonstrate a technical reason for requiring
>*implementers* provide a separate f/p stack.

Certainly no technical reason that you will acknowledge.

>That's because the
>existence of combined stack systems affected nobody but themselves.

The issue of whether the programmer has to write code such that it
works on both separate-stack and combined-stack systems affects all
programmers who write FP code.  And the programmers of the FSL voted
with their feet and did not write Forth-94 compliant programs, but
programs for separate-stack systems.  And popular systems provide
separate-stack implementations.  So separate stacks are common
practice.  If we did not put common practice in the standard, we would
not be doing our job.

But if you prefer to write Forth-94 compliant code (i.e., it works on
separate-stack systems and all flavours of combined-stack systems),
there's good news for you: You can continue doing that; this code is
also Forth-2012 compliant.

>All 200x did was take choice away from the implementer

Well, tough luck for the implementer.  Do we suffer from too few
implementors or from too few programmers?

But did we actually do that?  VFX still provides combined-stack
packages in addition to the separate-stack packages, and that's fine.
And even if you are an implementor who only wants to provide a
combined-stack package, the only thing taken away from you is the
possibility to label your system a "Forth-2012 system providing the
floating-point wordset".

>- something
>ANS went to lengths to avoid.

If they avoided taking away choice from the implementor, they would
not have required that OR performs an inclusive-or (and that's in
core, so it is a hard requirement).  Actually the only away to avoid
taking any choice away from implementors is to not require anything in
the standard.  Then the standard is completely useless, but it avoids
to "take choice away from the implementors".

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
     New standard: http://www.forth200x.org/forth200x.html
   EuroForth 2017: http://www.euroforth.org/ef17/

Thread

Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-13 07:34 +0000
  Re: Forth-94 vs. Forth-2012 FP data (long) pahihu <pahihu@gmail.com> - 2017-05-13 11:16 -0700
    Re: Forth-94 vs. Forth-2012 FP data (long) pahihu <pahihu@gmail.com> - 2017-05-13 11:49 -0700
      Re: Forth-94 vs. Forth-2012 FP data (long) pahihu <pahihu@gmail.com> - 2017-05-13 13:38 -0700
        Re: Forth-94 vs. Forth-2012 FP data (long) mhx@iae.nl - 2017-05-13 15:08 -0700
          Re: Forth-94 vs. Forth-2012 FP data (long) pahihu <pahihu@gmail.com> - 2017-05-14 00:51 -0700
          Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-14 07:32 +0000
            Re: Forth-94 vs. Forth-2012 FP data (long) mhx@iae.nl - 2017-05-14 02:46 -0700
              Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-14 14:57 +0000
                Re: Forth-94 vs. Forth-2012 FP data (long) krishna.myneni@ccreweb.org - 2017-05-15 19:11 -0700
    Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-14 08:14 +0000
  Re: Forth-94 vs. Forth-2012 FP data (long) Paul Rubin <no.email@nospam.invalid> - 2017-05-13 15:58 -0700
    Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-14 07:01 +0000
  Re: Forth-94 vs. Forth-2012 FP data (long) krishna.myneni@ccreweb.org - 2017-05-14 19:04 -0700
    Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-15 06:10 +0000
      Re: Forth-94 vs. Forth-2012 FP data (long) krishna.myneni@ccreweb.org - 2017-05-15 01:49 -0700
        Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-15 14:33 +0000
  Re: Forth-94 vs. Forth-2012 FP data (long) "HAA" <someone@microsoft.com> - 2017-05-15 13:44 +1000
    Re: Forth-94 vs. Forth-2012 FP data (long) Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-15 04:43 -0500
    Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-15 15:03 +0000
      Re: Forth-94 vs. Forth-2012 FP data (long) "HAA" <someone@microsoft.com> - 2017-05-17 00:10 +1000
  Re: Forth-94 vs. Forth-2012 FP data (long) pahihu <pahihu@gmail.com> - 2017-05-16 09:04 -0700
    Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-17 15:54 +0000
      Re: Forth-94 vs. Forth-2012 FP data (long) mhx@iae.nl - 2017-05-17 10:29 -0700
      Re: Forth-94 vs. Forth-2012 FP data (long) pahihu <pahihu@gmail.com> - 2017-05-17 23:53 -0700
        Re: Forth-94 vs. Forth-2012 FP data (long) pahihu <pahihu@gmail.com> - 2017-05-19 02:34 -0700
  Re: Forth-94 vs. Forth-2012 FP data (long) Joel Rees <joel.rees@gmail.com> - 2017-05-16 22:48 -0700
    Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-17 06:51 +0000
      Re: Forth-94 vs. Forth-2012 FP data (long) Joel Rees <joel.rees@gmail.com> - 2017-05-17 09:29 -0700
    Re: Forth-94 vs. Forth-2012 FP data (long) stephen@mpeforth.com (Stephen Pelc) - 2017-05-17 11:07 +0000
      Re: Forth-94 vs. Forth-2012 FP data (long) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-17 15:02 +0000

csiph-web