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Groups > comp.lang.forth > #58827
| From | anton@mips.complang.tuwien.ac.at (Anton Ertl) |
|---|---|
| Newsgroups | comp.lang.forth |
| Subject | FP stack (was: Recognizers discussion) |
| Date | 2017-05-08 12:35 +0000 |
| Organization | Institut fuer Computersprachen, Technische Universitaet Wien |
| Message-ID | <2017May8.143500@mips.complang.tuwien.ac.at> (permalink) |
| References | (4 earlier) <oeb2m3$tsb$2@dont-email.me> <dJidnfwN9rGQOJTEnZ2dnUU7-amdnZ2d@supernews.com> <6c191e71-1a1c-4b13-9c92-e82e0c836788@googlegroups.com> <77b0ca53-6bf4-4c73-a426-2504cb959544@googlegroups.com> <3bfb77ae-f710-4c37-8d5f-5d55a6cea02d@googlegroups.com> |
Joel Rees <joel.rees@gmail.com> writes:
>I've never understood the need for a separate floating point stack.
...
>But we put doubles, pointers, string pointers, string records, and all sort=
>s of other non-single-cell-integer non-scalar stuff on the parameter/local =
>state stack. Why not floating point, as well? (Especially, now that 32 bit =
>and 64 bit CPUs are becoming the norm, even in the embedded world.)
1) There is little overlap between integer and FP operations,
basically just the data-movement stuff @ ! DUP SWAP etc. By contrast,
we use, e.g., +, -, and u< on signed and unsigned integers, and on
addresses, and being able to access the individual cells of doubles
allows implementing various more refined operations (e.g., triple-cell
integers in M*/). Having the individual cells of a c-addr u string
descriptor accessible is the foundation for a number of string
operations, e.g., checking whether a string is a prefix of another
string. If we put these data on separate stacks, we would have to
introduce and then use all kinds of words for transfering cells
between these stacks; that's not the case for FP data.
2) How many cells should an FP value have on the data stack? 1? 2? 4?
None of these answers is good for all systems. Or maybe an FP value
should be an opaque type with an unspecified size? Then you cannot
access anything below it.
3) FP hardware usually works on separate FP registers, and transfers
between FP registers and integer registers are often pretty expensive
(sometimes they require a memory store and memory load). Many Forth
systems keep the top-of-data-stack in an integer register. On such a
system with a shared integer+FP-stack an FP operation would imply a
move from the integer registers to the FP registers and back. By
contrast, with a separate FP stack, the system can keep the
top-of-FP-stack in an FP register. On the 387 the whole Forth FP
stack is often kept in the 387 FP stack.
This has now come up several times, so I have added it to the FAQ:
https://www.complang.tuwien.ac.at/forth/faq/faq-general.html#toc5.15
- 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/
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Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-02 15:27 +0100
Recognizers discussion lehs <skydda.barnen@gmail.com> - 2017-05-02 07:52 -0700
Re: Recognizers discussion Mark Wills <markwills1970@gmail.com> - 2017-05-02 08:19 -0700
Re: Recognizers discussion lehs <skydda.barnen@gmail.com> - 2017-05-02 08:27 -0700
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-02 19:55 +0100
Re: Recognizers discussion lehs <skydda.barnen@gmail.com> - 2017-05-03 02:38 -0700
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-04 15:16 +0000
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-02 17:05 +0100
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-02 17:23 +0100
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-02 17:26 +0100
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-02 13:03 -0500
Re: Recognizers discussion Matthias Trute <matthias.trute@gmail.com> - 2017-05-02 12:44 -0700
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-03 04:36 -0500
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-04 13:28 +0000
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 09:13 -0500
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-02 12:35 -0500
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-02 18:53 +0100
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-02 13:10 -0500
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-02 19:22 +0100
Re: Recognizers discussion Bernd Paysan <bernd@net2o.de> - 2017-05-02 22:53 +0000
Re: Recognizers discussion Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2017-05-03 07:39 +0100
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-03 10:58 +0100
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-04 13:53 +0000
Re: Recognizers discussion Bernd Paysan <bernd@net2o.de> - 2017-05-06 01:21 +0000
Re: Recognizers discussion pahihu <pahihu@gmail.com> - 2017-05-06 00:22 -0700
Re: Recognizers discussion Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2017-05-06 23:05 +0100
Re: Recognizers discussion pahihu <pahihu@gmail.com> - 2017-05-06 22:36 -0700
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-03 04:38 -0500
Re: Recognizers discussion minforth@arcor.de - 2017-05-03 04:49 -0700
Re: Recognizers discussion Mark Wills <markwills1970@gmail.com> - 2017-05-03 05:03 -0700
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-03 09:02 -0500
Re: Recognizers discussion Mark Wills <markwills1970@gmail.com> - 2017-05-03 07:45 -0700
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-03 11:24 -0500
Re: Recognizers discussion Mark Wills <markwills1970@gmail.com> - 2017-05-03 09:45 -0700
Re: Recognizers discussion Raimond Dragomir <raimond.dragomir@gmail.com> - 2017-05-03 10:08 -0700
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-09 15:56 +0000
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-03 18:37 +0100
Re: Recognizers discussion Mark Wills <markwills1970@gmail.com> - 2017-05-03 11:07 -0700
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-03 20:55 +0100
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 02:47 -0500
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-04 13:07 +0100
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 07:59 -0500
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-04 17:38 +0100
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 12:42 -0500
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 02:43 -0500
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-04 13:05 +0100
Re: Recognizers discussion Ron Aaron <rambamist@gmail.com> - 2017-05-04 15:10 +0300
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-04 13:25 +0100
Re: Recognizers discussion Ron Aaron <rambamist@gmail.com> - 2017-05-04 15:33 +0300
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 08:05 -0500
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-09 15:54 +0000
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-09 11:10 -0500
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-10 11:49 +0000
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-04 16:14 +0000
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 13:02 -0500
Re: Recognizers discussion Bernd Paysan <bernd@net2o.de> - 2017-05-05 23:29 +0000
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-07 03:56 -0500
Re: Recognizers discussion Bernd Paysan <bernd@net2o.de> - 2017-05-07 22:42 +0000
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-08 04:08 -0500
Re: Recognizers discussion Julian Fondren <julian.fondren@gmail.com> - 2017-05-03 08:51 -0700
Re: Recognizers discussion Mark Wills <markwills1970@gmail.com> - 2017-05-03 09:38 -0700
Re: Recognizers discussion Julian Fondren <julian.fondren@gmail.com> - 2017-05-03 09:59 -0700
Re: Recognizers discussion Mark Wills <markwills1970@gmail.com> - 2017-05-03 10:16 -0700
Re: Recognizers discussion albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-03 22:04 +0200
Re: Recognizers discussion minforth@arcor.de - 2017-05-03 22:09 -0700
Re: Recognizers discussion Joel Rees <joel.rees@gmail.com> - 2017-05-07 19:50 -0700
Re: Recognizers discussion "Elizabeth D. Rather" <erather@forth.com> - 2017-05-07 21:33 -1000
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-08 04:12 -0500
Re: Recognizers discussion Joel Rees <joel.rees@gmail.com> - 2017-05-08 20:21 -0700
FP stack (was: Recognizers discussion) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-08 12:35 +0000
Re: FP stack (was: Recognizers discussion) Joel Rees <joel.rees@gmail.com> - 2017-05-08 20:50 -0700
Re: FP stack Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-09 03:39 -0500
Re: FP stack Joel Rees <joel.rees@gmail.com> - 2017-05-09 20:59 -0700
Re: FP stack Julian Fondren <julian.fondren@gmail.com> - 2017-05-10 00:03 -0700
Re: FP stack Alex <alex@rivadpm.com> - 2017-05-10 08:10 +0100
Re: FP stack "Elizabeth D. Rather" <erather@forth.com> - 2017-05-09 21:24 -1000
Re: FP stack Julian Fondren <julian.fondren@gmail.com> - 2017-05-10 00:37 -0700
Re: FP stack "Elizabeth D. Rather" <erather@forth.com> - 2017-05-09 22:53 -1000
Re: FP stack Alex <alex@rivadpm.com> - 2017-05-10 08:53 +0100
Re: FP stack Ron Aaron <rambamist@gmail.com> - 2017-05-10 11:00 +0300
Re: FP stack Paul Rubin <no.email@nospam.invalid> - 2017-05-10 01:02 -0700
Re: FP stack Ron Aaron <rambamist@gmail.com> - 2017-05-10 11:06 +0300
Re: FP stack anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-10 09:58 +0000
Re: FP stack Ron Aaron <rambamist@gmail.com> - 2017-05-10 14:17 +0300
Re: FP stack Alex <alex@rivadpm.com> - 2017-05-10 13:09 +0100
Re: FP stack anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-10 15:05 +0000
Re: FP stack albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-10 11:43 +0200
Re: FP stack "HAA" <someone@microsoft.com> - 2017-05-10 18:34 +1000
Re: FP stack anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-10 09:45 +0000
Re: FP stack "HAA" <someone@microsoft.com> - 2017-05-11 19:13 +1000
Re: FP stack Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-11 04:50 -0500
Re: FP stack anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-11 16:18 +0000
Re: FP stack Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-11 12:12 -0500
Re: FP stack stephen@mpeforth.com (Stephen Pelc) - 2017-05-11 13:53 +0000
Re: FP stack anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-11 15:43 +0000
Re: FP stack Joel Rees <joel.rees@gmail.com> - 2017-05-12 08:48 -0700
Re: FP stack anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-11 16:31 +0000
Re: FP stack "Elizabeth D. Rather" <erather@forth.com> - 2017-05-11 10:18 -1000
Re: FP stack Cecil Bayona <cbayona@cbayona.com> - 2017-05-11 15:37 -0500
Re: FP stack "Elizabeth D. Rather" <erather@forth.com> - 2017-05-11 17:25 -1000
Re: FP stack Cecil Bayona <cbayona@cbayona.com> - 2017-05-11 22:55 -0500
Re: FP stack "HAA" <someone@microsoft.com> - 2017-05-13 14:24 +1000
Re: FP stack albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-13 13:44 +0200
Re: FP stack Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-10 05:58 -0500
Re: FP stack (was: Recognizers discussion) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-09 13:50 +0000
Re: FP stack (was: Recognizers discussion) Joel Rees <joel.rees@gmail.com> - 2017-05-10 00:25 -0700
Re: FP stack (was: Recognizers discussion) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-10 11:39 +0000
Re: FP stack (was: Recognizers discussion) Joel Rees <joel.rees@gmail.com> - 2017-05-10 11:49 -0700
Re: FP stack (was: Recognizers discussion) "HAA" <someone@microsoft.com> - 2017-05-09 21:15 +1000
Re: Recognizers discussion "HAA" <someone@microsoft.com> - 2017-05-09 14:16 +1000
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-03 08:57 -0500
Re: Recognizers discussion minforth@arcor.de - 2017-05-03 07:54 -0700
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-03 11:30 -0500
Re: Recognizers discussion Cecil Bayona <cbayona@cbayona.com> - 2017-05-03 14:05 -0500
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-03 18:42 +0100
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 02:51 -0500
Re: Recognizers discussion "HAA" <someone@microsoft.com> - 2017-05-04 22:29 +1000
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-04 13:41 +0100
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-04 09:06 -0500
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-15 12:22 +0000
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-15 07:36 -0500
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-18 21:21 +0000
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-18 21:24 +0000
Re: Recognizers discussion albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-04 20:17 +0200
Re: Recognizers discussion "HAA" <someone@microsoft.com> - 2017-05-05 11:03 +1000
Re: Recognizers discussion minforth@arcor.de - 2017-05-05 00:16 -0700
Re: Recognizers discussion JUERGEN <epldfpga@aol.com> - 2017-05-05 13:15 -0700
Re: Recognizers discussion "HAA" <someone@microsoft.com> - 2017-05-06 16:49 +1000
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-05 21:00 +0100
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-09 14:17 +0000
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-09 15:46 +0100
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-10 11:50 +0000
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-10 13:11 +0100
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-10 13:49 +0000
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-10 15:57 +0100
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-12 14:17 +0000
Re: Recognizers discussion "Elizabeth D. Rather" <erather@forth.com> - 2017-05-02 09:25 -1000
Re: Recognizers discussion albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-03 01:19 +0200
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-05 15:50 +0000
Re: Recognizers discussion "HAA" <someone@microsoft.com> - 2017-05-08 11:43 +1000
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-08 19:17 +0000
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-09 14:25 +0000
Re: Recognizers discussion "Elizabeth D. Rather" <erather@forth.com> - 2017-05-09 21:22 -1000
Re: Recognizers discussion "HAA" <someone@microsoft.com> - 2017-05-13 13:33 +1000
Re: Recognizers discussion "Elizabeth D. Rather" <erather@forth.com> - 2017-05-12 21:32 -1000
Re: Recognizers discussion Howerd <howerdo@yahoo.co.uk> - 2017-05-13 07:12 -0700
Re: Recognizers discussion "Rudy Velthuis" <newsgroups@rvelthuis.de> - 2017-05-13 14:30 +0000
Re: Recognizers discussion rickman <gnuarm@gmail.com> - 2017-05-04 11:37 -0400
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-04 17:51 +0100
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-05 07:31 +0000
Re: Recognizers discussion Lars Brinkhoff <lars.spam@nocrew.org> - 2017-05-05 20:35 +0200
Re: Recognizers discussion minforth@arcor.de - 2017-05-05 12:27 -0700
Re: Recognizers discussion Cecil Bayona <cbayona@cbayona.com> - 2017-05-05 15:03 -0500
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-06 16:26 +0000
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-06 18:17 +0100
Re: Recognizers discussion Brad Eckert <hwfwguy@gmail.com> - 2017-05-06 12:26 -0700
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-06 21:39 +0100
Re: Recognizers discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-07 03:58 -0500
Re: Recognizers discussion Alex <alex@rivadpm.com> - 2017-05-07 10:39 +0100
Re: Recognizers discussion Bernd Paysan <bernd@net2o.de> - 2017-05-07 23:39 +0000
Re: Recognizers discussion Paul Rubin <no.email@nospam.invalid> - 2017-05-07 17:38 -0700
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-08 13:40 +0000
Re: Recognizers discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-08 13:25 +0000
Re: Recognizers discussion Lars Brinkhoff <lars.spam@nocrew.org> - 2017-05-08 16:25 +0200
Flash (was: Recognizers discussion) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-07 10:51 +0000
Re: Flash Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-07 08:06 -0500
Re: Flash anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-07 13:57 +0000
Re: Flash Lars Brinkhoff <lars.spam@nocrew.org> - 2017-05-07 16:46 +0200
Re: Flash Alex <alex@rivadpm.com> - 2017-05-07 16:31 +0100
Re: Flash anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-07 17:16 +0000
Re: Flash Alex <alex@rivadpm.com> - 2017-05-07 19:18 +0100
Re: Flash albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-07 21:45 +0200
Re: Flash Matthias Trute <matthias.trute@gmail.com> - 2017-05-07 12:54 -0700
Re: Flash Alex <alex@rivadpm.com> - 2017-05-07 19:33 +0100
Re: Flash Raimond Dragomir <raimond.dragomir@gmail.com> - 2017-05-07 08:50 -0700
Re: Flash anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-07 17:21 +0000
Re: Recognizers discussion Matthias Trute <matthias.trute@gmail.com> - 2017-05-04 10:07 -0700
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