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Groups > comp.lang.forth > #42906
| From | anton@mips.complang.tuwien.ac.at (Anton Ertl) |
|---|---|
| Newsgroups | comp.lang.forth |
| Subject | Re: Preserving standard and common use names (Re: alternatives to `find`) |
| Date | 2015-10-28 15:56 +0000 |
| Organization | Institut fuer Computersprachen, Technische Universitaet Wien |
| Message-ID | <2015Oct28.165626@mips.complang.tuwien.ac.at> (permalink) |
| References | (5 earlier) <9c09885c-6f8e-4ce7-b58e-ee71ccf4076e@googlegroups.com> <2015Oct26.115859@mips.complang.tuwien.ac.at> <46986dbe-0807-4e88-a8d5-c69ed9ef4a84@googlegroups.com> <2015Oct27.180941@mips.complang.tuwien.ac.at> <5630c0b8.248998702@news.eternal-september.org> |
stephen@mpeforth.com (Stephen Pelc) writes:
>On Tue, 27 Oct 2015 17:09:41 GMT, anton@mips.complang.tuwien.ac.at
>(Anton Ertl) wrote:
>That would be me. I'll attempt to provide some numbers for you in my
>"ample spare time".
Ideally that would be numbers for a Forth-94 program (where the
program has to work around the fact that it does not know whether the
FP stack is separate or shared), a Forth-2012 program (which can rely
on a separate FP stack), and a program with an environmental
dependency on a shared stack and single-cell FP values.
>In my particular case, I see that Cortex-M4F provides single-precision
>(32 bit) floating point instructions. Having a separate FP stack
>implemented efficiently costs an extra register and careful memory
>control.
If you want efficient FP, you won't be using the Cortex-M4F. Every
CPU where FP efficiency plays a role (including higher-performance
ARMs), uses a separate FP register file; that was true in the CDC 6600
in 1965, and it's true now, 50 years later, and the reason for that is
physics. And implementing a shared stack for such CPUs is
inefficient.
> As Klaus showed at EuroForth 2015, 32 bit FP has a point.
It's good enough for some applications, but many others need more.
CPU manufacturers don't make 64-bit FPUs because they don't know what
to do with the transistors, but because they are needed by
applications. And they are longer in the FP business than Klaus, and
know more about it.
>It will become more common in the future.
Any evidence to support that claim?
Counter-evidence: When I google for "ARM Floating Point",
> A shared data stack is looking
>like a good compromise.
Let's see:
1) On one hand, everybody who is interested in high-performance FP is
working on CPUs where a separate stack provides a good performance
advantage (as well as making programming easier).
2) And then there are the people who are not really interested in
high-performance FP, so they buy a Cortex-M4F; yet they want everybody
else to have slower FP (and, in many cases, insufficiently accurate
FP) in order to have faster FP themselves.
Giving in to the second group of people really looks like a good
compromise. Not!
>So we see that assumptions made in one decade may be wrong in another.
But in this case they are not.
>In an embedded system, code size, data size and performance trump
>anything that a standard says.
In that case, why care about what the standard says? Just implement
FP for the Cortex-M4F to have an environmental restriction of a shared
stack and single-cell FP values, and write programs with an
environmental dependency on a shared stack and single-cell FP values,
and be happy. Or you could go the traditional MPE way and provide
several floating-point packages, a standard one and one that is fast
for the Cortex-M4F.
- 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 2015: http://www.rigwit.co.uk/EuroForth2015/
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alternatives to `find` Marcos Cruz <use_the_contact_page@programandala.net> - 2015-10-21 20:09 +0000
Re: alternatives to `find` anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-22 05:54 +0000
Re: alternatives to `find` Marcos Cruz <use_the_contact_page@programandala.net> - 2015-10-22 15:37 +0000
Re: alternatives to `find` Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-10-22 22:03 -0700
Re: alternatives to `find` Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-10-22 22:14 -0700
Re: alternatives to `find` hughaguilar96@gmail.com - 2015-10-23 01:28 -0700
Re: alternatives to `find` Marcos Cruz <use_the_contact_page@programandala.net> - 2015-10-23 12:12 +0000
Re: alternatives to `find` anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-26 11:39 +0000
Re: alternatives to `find` Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-10-26 05:14 -0700
Re: alternatives to `find` Marcos Cruz <use_the_contact_page@programandala.net> - 2015-10-23 12:30 +0000
Re: alternatives to `find` Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-10-23 22:52 -0700
Re: alternatives to `find` Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-10-23 23:14 -0700
Re: alternatives to `find` Marcos Cruz <use_the_contact_page@programandala.net> - 2015-10-24 11:15 +0000
Re: alternatives to `find` Coos Haak <chforth@hccnet.nl> - 2015-10-24 14:34 +0200
Re: alternatives to `find` anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-24 14:45 +0000
Re: alternatives to `find` Coos Haak <chforth@hccnet.nl> - 2015-10-24 17:23 +0200
Preserving standard and common use names (Re: alternatives to `find`) Marcos Cruz <use_the_contact_page@programandala.net> - 2015-10-24 11:53 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-10-24 22:48 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) "Elizabeth D. Rather" <erather@forth.com> - 2015-10-24 21:05 -1000
Re: Preserving standard and common use names (Re: alternatives to `find`) Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-10-25 01:34 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) "Elizabeth D. Rather" <erather@forth.com> - 2015-10-24 22:45 -1000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-25 09:16 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) "Elizabeth D. Rather" <erather@forth.com> - 2015-10-25 08:46 -1000
Re: Preserving standard and common use names (Re: alternatives to `find`) hughaguilar96@gmail.com - 2015-10-25 21:31 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) Bernd Paysan <bernd.paysan@gmx.de> - 2015-10-25 18:50 +0100
Re: Preserving standard and common use names (Re: alternatives to `find`) Mark Wills <markwills1970@gmail.com> - 2015-10-26 01:57 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) Paul Rubin <no.email@nospam.invalid> - 2015-10-26 02:07 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) Ron Aaron <rambamist@gmail.com> - 2015-10-26 11:14 +0200
Re: Preserving standard and common use names (Re: alternatives to `find`) Mark Wills <markwills1970@gmail.com> - 2015-10-26 04:18 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) "Elizabeth D. Rather" <erather@forth.com> - 2015-10-26 09:22 -1000
Re: Preserving standard and common use names (Re: alternatives to `find`) hughaguilar96@gmail.com - 2015-10-26 21:34 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-26 10:58 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Mark Wills <markwills1970@gmail.com> - 2015-10-26 05:59 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) Bernd Paysan <bernd.paysan@gmx.de> - 2015-10-26 14:58 +0100
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-27 17:09 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-28 12:50 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-28 15:56 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Paul Rubin <no.email@nospam.invalid> - 2015-10-28 10:31 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) Bernd Paysan <bernd.paysan@gmx.de> - 2015-10-28 19:26 +0100
Re: Preserving standard and common use names (Re: alternatives to `find`) Paul Rubin <no.email@nospam.invalid> - 2015-10-28 12:37 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-28 23:03 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Paul Rubin <no.email@nospam.invalid> - 2015-10-28 16:21 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) Bernd Paysan <bernd.paysan@gmx.de> - 2015-10-28 20:37 +0100
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-28 23:13 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Bernd Paysan <bernd.paysan@gmx.de> - 2015-10-29 03:01 +0100
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-29 10:04 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-29 15:29 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Mark Wills <markwills1970@gmail.com> - 2015-10-30 04:17 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2015-10-30 11:36 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-31 15:25 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2015-10-31 20:34 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2015-10-30 20:51 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Mark Wills <markwills1970@gmail.com> - 2015-11-02 01:39 -0800
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-11-02 11:12 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2015-11-02 12:09 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Mark Wills <markwills1970@gmail.com> - 2015-11-02 05:09 -0800
Re: Preserving standard and common use names (Re: alternatives to `find`) Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-11-02 06:23 -0800
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-11-02 14:39 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2015-11-20 16:20 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Mark Wills <markwills1970@gmail.com> - 2015-11-21 00:26 -0800
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-31 15:03 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-31 16:35 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-11-01 14:07 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Bernd Paysan <bernd.paysan@gmx.de> - 2015-11-01 21:05 +0100
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-31 16:31 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Bernd Paysan <bernd.paysan@gmx.de> - 2015-10-31 20:33 +0100
Re: Preserving standard and common use names (Re: alternatives to `find`) Bernd Paysan <bernd.paysan@gmx.de> - 2015-10-29 22:27 +0100
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-29 13:19 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-29 10:00 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-29 13:29 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-29 14:04 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-29 16:29 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-29 16:42 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-29 16:13 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) mhx@iae.nl - 2015-10-29 12:19 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-31 14:12 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) stephen@mpeforth.com (Stephen Pelc) - 2015-10-31 16:49 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) Paul Rubin <no.email@nospam.invalid> - 2015-10-31 10:33 -0700
Re: Preserving standard and common use names (Re: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-11-01 14:14 +0000
Re: Preserving standard and common use names (Re: alternatives to `find`) hughaguilar96@gmail.com - 2015-10-25 21:52 -0700
Re: alternatives to `find` Albert van der Horst <albert@spenarnc.xs4all.nl> - 2015-10-30 12:30 +0000
Re: alternatives to `find` anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-10-26 11:47 +0000
Re: alternatives to `find` Chris Curl <ccurl609@gmail.com> - 2015-11-02 06:17 -0800
Re: alternatives to `find` Mark Wills <markwills1970@gmail.com> - 2015-11-02 06:35 -0800
Re: alternatives to `find` Coos Haak <chforth@hccnet.nl> - 2015-11-02 15:45 +0100
Re: alternatives to `find` Chris Curl <ccurl609@gmail.com> - 2015-11-02 07:17 -0800
Re: alternatives to `find` Albert van der Horst <albert@spenarnc.xs4all.nl> - 2015-11-02 19:39 +0000
Re: alternatives to `find` Mark Wills <markwills1970@gmail.com> - 2015-11-02 12:19 -0800
Re: alternatives to `find` anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-11-03 11:31 +0000
Re: alternatives to `find` Albert van der Horst <albert@spenarnc.xs4all.nl> - 2015-11-03 21:11 +0000
MOVE and CMOVE speed (was: alternatives to `find`) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-11-04 09:52 +0000
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