version 1.42, 1997/01/14 16:30:50
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version 1.46, 1997/03/19 18:27:15
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Line 7
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Line 7
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@comment %**end of header (This is for running Texinfo on a region.) |
@comment %**end of header (This is for running Texinfo on a region.) |
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@ifinfo |
@ifinfo |
This file documents Gforth 0.2 |
This file documents Gforth 0.3 |
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Copyright @copyright{} 1995,1996 Free Software Foundation, Inc. |
Copyright @copyright{} 1995-1997 Free Software Foundation, Inc. |
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Permission is granted to make and distribute verbatim copies of |
Permission is granted to make and distribute verbatim copies of |
this manual provided the copyright notice and this permission notice |
this manual provided the copyright notice and this permission notice |
Line 41 Copyright @copyright{} 1995,1996 Free So
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Line 41 Copyright @copyright{} 1995,1996 Free So
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@sp 10 |
@sp 10 |
@center @titlefont{Gforth Manual} |
@center @titlefont{Gforth Manual} |
@sp 2 |
@sp 2 |
@center for version 0.2 |
@center for version 0.3 |
@sp 2 |
@sp 2 |
@center Anton Ertl |
@center Anton Ertl |
@center Bernd Paysan |
@center Bernd Paysan |
Line 51 Copyright @copyright{} 1995,1996 Free So
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Line 51 Copyright @copyright{} 1995,1996 Free So
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@comment The following two commands start the copyright page. |
@comment The following two commands start the copyright page. |
@page |
@page |
@vskip 0pt plus 1filll |
@vskip 0pt plus 1filll |
Copyright @copyright{} 1995,1996 Free Software Foundation, Inc. |
Copyright @copyright{} 1995--1997 Free Software Foundation, Inc. |
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@comment !! Published by ... or You can get a copy of this manual ... |
@comment !! Published by ... or You can get a copy of this manual ... |
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Line 77 Copyright @copyright{} 1995,1996 Free So
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Line 77 Copyright @copyright{} 1995,1996 Free So
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@node Top, License, (dir), (dir) |
@node Top, License, (dir), (dir) |
@ifinfo |
@ifinfo |
Gforth is a free implementation of ANS Forth available on many |
Gforth is a free implementation of ANS Forth available on many |
personal machines. This manual corresponds to version 0.2. |
personal machines. This manual corresponds to version 0.3. |
@end ifinfo |
@end ifinfo |
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|
@menu |
@menu |
* License:: |
* License:: |
* Goals:: About the Gforth Project |
* Goals:: About the Gforth Project |
* Other Books:: Things you might want to read |
* Other Books:: Things you might want to read |
* Invocation:: Starting Gforth |
* Invoking Gforth:: Starting Gforth |
* Words:: Forth words available in Gforth |
* Words:: Forth words available in Gforth |
* Tools:: Programming tools |
* Tools:: Programming tools |
* ANS conformance:: Implementation-defined options etc. |
* ANS conformance:: Implementation-defined options etc. |
* Model:: The abstract machine of Gforth |
* Model:: The abstract machine of Gforth |
* Integrating Gforth:: Forth as scripting language for applications. |
* Integrating Gforth:: Forth as scripting language for applications |
* Emacs and Gforth:: The Gforth Mode |
* Emacs and Gforth:: The Gforth Mode |
* Internals:: Implementation details |
* Image Files:: @code{.fi} files contain compiled code |
|
* Engine:: The inner interpreter and the primitives |
* Bugs:: How to report them |
* Bugs:: How to report them |
* Origin:: Authors and ancestors of Gforth |
* Origin:: Authors and ancestors of Gforth |
* Word Index:: An item for each Forth word |
* Word Index:: An item for each Forth word |
* Node Index:: An item for each node |
* Concept Index:: A menu covering many topics |
@end menu |
@end menu |
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|
@node License, Goals, Top, Top |
@node License, Preface, Top, Top |
@unnumbered GNU GENERAL PUBLIC LICENSE |
@unnumbered GNU GENERAL PUBLIC LICENSE |
@center Version 2, June 1991 |
@center Version 2, June 1991 |
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Line 491 library. If this is what you want to do
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Line 492 library. If this is what you want to do
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Public License instead of this License. |
Public License instead of this License. |
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@iftex |
@iftex |
@node Preface |
@node Preface, Goals, License, Top |
@comment node-name, next, previous, up |
@comment node-name, next, previous, up |
@unnumbered Preface |
@unnumbered Preface |
@cindex Preface |
@cindex Preface |
Line 500 Forth. This manual is primarily a refere
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Line 501 Forth. This manual is primarily a refere
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for introductory material. |
for introductory material. |
@end iftex |
@end iftex |
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@node Goals, Other Books, License, Top |
@node Goals, Other Books, Preface, Top |
@comment node-name, next, previous, up |
@comment node-name, next, previous, up |
@chapter Goals of Gforth |
@chapter Goals of Gforth |
@cindex Goals |
@cindex Goals |
The goal of the Gforth Project is to develop a standard model for |
The goal of the Gforth Project is to develop a standard model for |
ANSI Forth. This can be split into several subgoals: |
ANS Forth. This can be split into several subgoals: |
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|
@itemize @bullet |
@itemize @bullet |
@item |
@item |
Gforth should conform to the ANSI Forth standard. |
Gforth should conform to the Forth standard (ANS Forth). |
@item |
@item |
It should be a model, i.e. it should define all the |
It should be a model, i.e. it should define all the |
implementation-dependent things. |
implementation-dependent things. |
Line 543 powerful features, but not yet everythin
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Line 544 powerful features, but not yet everythin
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certainly have achieved our execution speed goals (@pxref{Performance}). |
certainly have achieved our execution speed goals (@pxref{Performance}). |
It is free and available on many machines. |
It is free and available on many machines. |
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|
@node Other Books, Invocation, Goals, Top |
@node Other Books, Invoking Gforth, Goals, Top |
@chapter Other books on ANS Forth |
@chapter Other books on ANS Forth |
|
@cindex books on Forth |
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|
As the standard is relatively new, there are not many books out yet. It |
As the standard is relatively new, there are not many books out yet. It |
is not recommended to learn Forth by using Gforth and a book that is |
is not recommended to learn Forth by using Gforth and a book that is |
not written for ANS Forth, as you will not know your mistakes from the |
not written for ANS Forth, as you will not know your mistakes from the |
deviations of the book. |
deviations of the book. |
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|
@cindex standard document for ANS Forth |
|
@cindex ANS Forth document |
There is, of course, the standard, the definite reference if you want to |
There is, of course, the standard, the definite reference if you want to |
write ANS Forth programs. It is available in printed form from the |
write ANS Forth programs. It is available in printed form from the |
National Standards Institute Sales Department (Tel.: USA (212) 642-4900; |
National Standards Institute Sales Department (Tel.: USA (212) 642-4900; |
Line 564 format, and it has been converted to HTM
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Line 568 format, and it has been converted to HTM
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versions can be found through |
versions can be found through |
@*@file{http://www.complang.tuwien.ac.at/projects/forth.html}. |
@*@file{http://www.complang.tuwien.ac.at/projects/forth.html}. |
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|
@cite{Forth: The new model} by Jack Woehr (Prentice-Hall, 1993) is an |
@cindex introductory book |
|
@cindex book, introductory |
|
@cindex Woehr, Jack: @cite{Forth: The New Model} |
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@cindex @cite{Forth: The new model} (book) |
|
@cite{Forth: The New Model} by Jack Woehr (Prentice-Hall, 1993) is an |
introductory book based on a draft version of the standard. It does not |
introductory book based on a draft version of the standard. It does not |
cover the whole standard. It also contains interesting background |
cover the whole standard. It also contains interesting background |
information (Jack Woehr was in the ANS Forth Technical Committee). It is |
information (Jack Woehr was in the ANS Forth Technical Committee). It is |
not appropriate for complete newbies, but programmers experienced in |
not appropriate for complete newbies, but programmers experienced in |
other languages should find it ok. |
other languages should find it ok. |
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|
@node Invocation, Words, Other Books, Top |
@node Invoking Gforth, Words, Other Books, Top |
@chapter Invocation |
@chapter Invoking Gforth |
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@cindex invoking Gforth |
|
@cindex running Gforth |
|
@cindex command-line options |
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@cindex options on the command line |
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@cindex flags on the command line |
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|
You will usually just say @code{gforth}. In many other cases the default |
You will usually just say @code{gforth}. In many other cases the default |
Gforth image will be invoked like this: |
Gforth image will be invoked like this: |
Line 594 The initialization options must come bef
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Line 607 The initialization options must come bef
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line. They are: |
line. They are: |
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@table @code |
@table @code |
|
@cindex -i, command-line option |
|
@cindex --image-file, command-line option |
@item --image-file @var{file} |
@item --image-file @var{file} |
@item -i @var{file} |
@itemx -i @var{file} |
Loads the Forth image @var{file} instead of the default |
Loads the Forth image @var{file} instead of the default |
@file{gforth.fi}. |
@file{gforth.fi} (@pxref{Image Files}). |
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|
@cindex --path, command-line option |
|
@cindex -p, command-line option |
@item --path @var{path} |
@item --path @var{path} |
@item -p @var{path} |
@itemx -p @var{path} |
Uses @var{path} for searching the image file and Forth source code files |
Uses @var{path} for searching the image file and Forth source code files |
instead of the default in the environment variable @code{GFORTHPATH} or |
instead of the default in the environment variable @code{GFORTHPATH} or |
the path specified at installation time (e.g., |
the path specified at installation time (e.g., |
@file{/usr/local/share/gforth/0.2.0:.}). A path is given as a list of |
@file{/usr/local/share/gforth/0.2.0:.}). A path is given as a list of |
directories, separated by @samp{:} (on Unix) or @samp{;} (on other OSs). |
directories, separated by @samp{:} (on Unix) or @samp{;} (on other OSs). |
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@cindex --dictionary-size, command-line option |
|
@cindex -m, command-line option |
|
@cindex @var{size} parameters for command-line options |
|
@cindex size of the dictionary and the stacks |
@item --dictionary-size @var{size} |
@item --dictionary-size @var{size} |
@item -m @var{size} |
@itemx -m @var{size} |
Allocate @var{size} space for the Forth dictionary space instead of |
Allocate @var{size} space for the Forth dictionary space instead of |
using the default specified in the image (typically 256K). The |
using the default specified in the image (typically 256K). The |
@var{size} specification consists of an integer and a unit (e.g., |
@var{size} specification consists of an integer and a unit (e.g., |
Line 616 using the default specified in the image
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Line 637 using the default specified in the image
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size, in this case Cells), @code{k} (kilobytes), and @code{M} |
size, in this case Cells), @code{k} (kilobytes), and @code{M} |
(Megabytes). If no unit is specified, @code{e} is used. |
(Megabytes). If no unit is specified, @code{e} is used. |
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|
@cindex --data-stack-size, command-line option |
|
@cindex -d, command-line option |
@item --data-stack-size @var{size} |
@item --data-stack-size @var{size} |
@item -d @var{size} |
@itemx -d @var{size} |
Allocate @var{size} space for the data stack instead of using the |
Allocate @var{size} space for the data stack instead of using the |
default specified in the image (typically 16K). |
default specified in the image (typically 16K). |
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|
@cindex --return-stack-size, command-line option |
|
@cindex -r, command-line option |
@item --return-stack-size @var{size} |
@item --return-stack-size @var{size} |
@item -r @var{size} |
@itemx -r @var{size} |
Allocate @var{size} space for the return stack instead of using the |
Allocate @var{size} space for the return stack instead of using the |
default specified in the image (typically 16K). |
default specified in the image (typically 15K). |
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|
|
@cindex --fp-stack-size, command-line option |
|
@cindex -f, command-line option |
@item --fp-stack-size @var{size} |
@item --fp-stack-size @var{size} |
@item -f @var{size} |
@itemx -f @var{size} |
Allocate @var{size} space for the floating point stack instead of |
Allocate @var{size} space for the floating point stack instead of |
using the default specified in the image (typically 16K). In this case |
using the default specified in the image (typically 15.5K). In this case |
the unit specifier @code{e} refers to floating point numbers. |
the unit specifier @code{e} refers to floating point numbers. |
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@cindex --locals-stack-size, command-line option |
|
@cindex -l, command-line option |
@item --locals-stack-size @var{size} |
@item --locals-stack-size @var{size} |
@item -l @var{size} |
@itemx -l @var{size} |
Allocate @var{size} space for the locals stack instead of using the |
Allocate @var{size} space for the locals stack instead of using the |
default specified in the image (typically 16K). |
default specified in the image (typically 14.5K). |
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@cindex -h, command-line option |
|
@cindex --help, command-line option |
|
@item --help |
|
@itemx -h |
|
Print a message about the command-line options |
|
|
|
@cindex -v, command-line option |
|
@cindex --version, command-line option |
|
@item --version |
|
@itemx -v |
|
Print version and exit |
|
|
|
@cindex --debug, command-line option |
|
@item --debug |
|
Print some information useful for debugging on startup. |
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@cindex --offset-image, command-line option |
|
@item --offset-image |
|
Start the dictionary at a slightly different position than would be used |
|
otherwise (useful for creating data-relocatable images, |
|
@pxref{Data-Relocatable Image Files}). |
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|
|
@cindex --clear-dictionary, command-line option |
|
@item --clear-dictionary |
|
Initialize all bytes in the dictionary to 0 before loading the image |
|
(@pxref{Data-Relocatable Image Files}). |
@end table |
@end table |
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@cindex loading files at startup |
|
@cindex executing code on startup |
|
@cindex batch processing with Gforth |
As explained above, the image-specific command-line arguments for the |
As explained above, the image-specific command-line arguments for the |
default image @file{gforth.fi} consist of a sequence of filenames and |
default image @file{gforth.fi} consist of a sequence of filenames and |
@code{-e @var{forth-code}} options that are interpreted in the sequence |
@code{-e @var{forth-code}} options that are interpreted in the sequence |
Line 649 Forth words, you have to quote them or u
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Line 707 Forth words, you have to quote them or u
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after processing the command line (instead of entering interactive mode) |
after processing the command line (instead of entering interactive mode) |
append @code{-e bye} to the command line. |
append @code{-e bye} to the command line. |
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|
@cindex versions, invoking other versions of Gforth |
If you have several versions of Gforth installed, @code{gforth} will |
If you have several versions of Gforth installed, @code{gforth} will |
invoke the version that was installed last. @code{gforth-@var{version}} |
invoke the version that was installed last. @code{gforth-@var{version}} |
invokes a specific version. You may want to use the option |
invokes a specific version. You may want to use the option |
Line 663 the user initialization file @file{.gfor
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Line 722 the user initialization file @file{.gfor
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option @code{--no-rc} is given; this file is first searched in @file{.}, |
option @code{--no-rc} is given; this file is first searched in @file{.}, |
then in @file{~}, then in the normal path (see above). |
then in @file{~}, then in the normal path (see above). |
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@node Words, Tools, Invocation, Top |
@node Words, Tools, Invoking Gforth, Top |
@chapter Forth Words |
@chapter Forth Words |
|
@cindex Words |
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|
@menu |
@menu |
* Notation:: |
* Notation:: |
* Arithmetic:: |
* Arithmetic:: |
* Stack Manipulation:: |
* Stack Manipulation:: |
* Memory access:: |
* Memory:: |
* Control Structures:: |
* Control Structures:: |
* Locals:: |
* Locals:: |
* Defining Words:: |
* Defining Words:: |
Line 686 then in @file{~}, then in the normal pat
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Line 746 then in @file{~}, then in the normal pat
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@node Notation, Arithmetic, Words, Words |
@node Notation, Arithmetic, Words, Words |
@section Notation |
@section Notation |
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@cindex notation of glossary entries |
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@cindex format of glossary entries |
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@cindex glossary notation format |
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@cindex word glossary entry format |
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The Forth words are described in this section in the glossary notation |
The Forth words are described in this section in the glossary notation |
that has become a de-facto standard for Forth texts, i.e. |
that has become a de-facto standard for Forth texts, i.e., |
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@format |
@format |
@var{word} @var{Stack effect} @var{wordset} @var{pronunciation} |
@var{word} @var{Stack effect} @var{wordset} @var{pronunciation} |
Line 697 that has become a de-facto standard for
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Line 761 that has become a de-facto standard for
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@table @var |
@table @var |
@item word |
@item word |
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@cindex case insensitivity |
The name of the word. BTW, Gforth is case insensitive, so you can |
The name of the word. BTW, Gforth is case insensitive, so you can |
type the words in in lower case (However, @pxref{core-idef}). |
type the words in in lower case (However, @pxref{core-idef}). |
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@item Stack effect |
@item Stack effect |
|
@cindex stack effect |
The stack effect is written in the notation @code{@var{before} -- |
The stack effect is written in the notation @code{@var{before} -- |
@var{after}}, where @var{before} and @var{after} describe the top of |
@var{after}}, where @var{before} and @var{after} describe the top of |
stack entries before and after the execution of the word. The rest of |
stack entries before and after the execution of the word. The rest of |
Line 719 this standard behaviour, or the word doe
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Line 785 this standard behaviour, or the word doe
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compile time, both stack effects are shown; otherwise only the run-time |
compile time, both stack effects are shown; otherwise only the run-time |
stack effect is shown. |
stack effect is shown. |
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@cindex pronounciation of words |
@item pronunciation |
@item pronunciation |
How the word is pronounced |
How the word is pronounced. |
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@cindex wordset |
@item wordset |
@item wordset |
The ANS Forth standard is divided into several wordsets. A standard |
The ANS Forth standard is divided into several wordsets. A standard |
system need not support all of them. So, the fewer wordsets your program |
system need not support all of them. So, the fewer wordsets your program |
Line 738 strings are also displayed like words; y
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Line 806 strings are also displayed like words; y
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A description of the behaviour of the word. |
A description of the behaviour of the word. |
@end table |
@end table |
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@cindex types of stack items |
|
@cindex stack item types |
The type of a stack item is specified by the character(s) the name |
The type of a stack item is specified by the character(s) the name |
starts with: |
starts with: |
|
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@table @code |
@table @code |
@item f |
@item f |
Bool, i.e. @code{false} or @code{true}. |
@cindex @code{f}, stack item type |
|
Boolean flags, i.e. @code{false} or @code{true}. |
@item c |
@item c |
|
@cindex @code{c}, stack item type |
Char |
Char |
@item w |
@item w |
|
@cindex @code{w}, stack item type |
Cell, can contain an integer or an address |
Cell, can contain an integer or an address |
@item n |
@item n |
|
@cindex @code{n}, stack item type |
signed integer |
signed integer |
@item u |
@item u |
|
@cindex @code{u}, stack item type |
unsigned integer |
unsigned integer |
@item d |
@item d |
|
@cindex @code{d}, stack item type |
double sized signed integer |
double sized signed integer |
@item ud |
@item ud |
|
@cindex @code{ud}, stack item type |
double sized unsigned integer |
double sized unsigned integer |
@item r |
@item r |
|
@cindex @code{r}, stack item type |
Float (on the FP stack) |
Float (on the FP stack) |
@item a_ |
@item a_ |
|
@cindex @code{a_}, stack item type |
Cell-aligned address |
Cell-aligned address |
@item c_ |
@item c_ |
|
@cindex @code{c_}, stack item type |
Char-aligned address (note that a Char may have two bytes in Windows NT) |
Char-aligned address (note that a Char may have two bytes in Windows NT) |
@item f_ |
@item f_ |
|
@cindex @code{f_}, stack item type |
Float-aligned address |
Float-aligned address |
@item df_ |
@item df_ |
|
@cindex @code{df_}, stack item type |
Address aligned for IEEE double precision float |
Address aligned for IEEE double precision float |
@item sf_ |
@item sf_ |
|
@cindex @code{sf_}, stack item type |
Address aligned for IEEE single precision float |
Address aligned for IEEE single precision float |
@item xt |
@item xt |
|
@cindex @code{xt}, stack item type |
Execution token, same size as Cell |
Execution token, same size as Cell |
@item wid |
@item wid |
|
@cindex @code{wid}, stack item type |
Wordlist ID, same size as Cell |
Wordlist ID, same size as Cell |
@item f83name |
@item f83name |
|
@cindex @code{f83name}, stack item type |
Pointer to a name structure |
Pointer to a name structure |
@item " |
@item " |
|
@cindex @code{"}, stack item type |
string in the input stream (not the stack). The terminating character is |
string in the input stream (not the stack). The terminating character is |
a blank by default. If it is not a blank, it is shown in @code{<>} |
a blank by default. If it is not a blank, it is shown in @code{<>} |
quotes. |
quotes. |
|
|
@end table |
@end table |
|
|
@node Arithmetic, Stack Manipulation, Notation, Words |
@node Arithmetic, Stack Manipulation, Notation, Words |
@section Arithmetic |
@section Arithmetic |
|
@cindex arithmetic words |
|
|
|
@cindex division with potentially negative operands |
Forth arithmetic is not checked, i.e., you will not hear about integer |
Forth arithmetic is not checked, i.e., you will not hear about integer |
overflow on addition or multiplication, you may hear about division by |
overflow on addition or multiplication, you may hear about division by |
zero if you are lucky. The operator is written after the operands, but |
zero if you are lucky. The operator is written after the operands, but |
Line 803 former, @pxref{Mixed precision}).
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Line 892 former, @pxref{Mixed precision}).
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|
|
@node Single precision, Bitwise operations, Arithmetic, Arithmetic |
@node Single precision, Bitwise operations, Arithmetic, Arithmetic |
@subsection Single precision |
@subsection Single precision |
|
@cindex single precision arithmetic words |
|
|
doc-+ |
doc-+ |
doc-- |
doc-- |
doc-* |
doc-* |
Line 816 doc-max
|
Line 907 doc-max
|
|
|
@node Bitwise operations, Mixed precision, Single precision, Arithmetic |
@node Bitwise operations, Mixed precision, Single precision, Arithmetic |
@subsection Bitwise operations |
@subsection Bitwise operations |
|
@cindex bitwise operation words |
|
|
doc-and |
doc-and |
doc-or |
doc-or |
doc-xor |
doc-xor |
Line 825 doc-2/
|
Line 918 doc-2/
|
|
|
@node Mixed precision, Double precision, Bitwise operations, Arithmetic |
@node Mixed precision, Double precision, Bitwise operations, Arithmetic |
@subsection Mixed precision |
@subsection Mixed precision |
|
@cindex mixed precision arithmetic words |
|
|
doc-m+ |
doc-m+ |
doc-*/ |
doc-*/ |
doc-*/mod |
doc-*/mod |
Line 837 doc-sm/rem
|
Line 932 doc-sm/rem
|
|
|
@node Double precision, Floating Point, Mixed precision, Arithmetic |
@node Double precision, Floating Point, Mixed precision, Arithmetic |
@subsection Double precision |
@subsection Double precision |
|
@cindex double precision arithmetic words |
|
|
|
@cindex double-cell numbers, input format |
|
@cindex input format for double-cell numbers |
The outer (aka text) interpreter converts numbers containing a dot into |
The outer (aka text) interpreter converts numbers containing a dot into |
a double precision number. Note that only numbers with the dot as last |
a double precision number. Note that only numbers with the dot as last |
character are standard-conforming. |
character are standard-conforming. |
Line 851 doc-dmax
|
Line 949 doc-dmax
|
|
|
@node Floating Point, , Double precision, Arithmetic |
@node Floating Point, , Double precision, Arithmetic |
@subsection Floating Point |
@subsection Floating Point |
|
@cindex floating point arithmetic words |
|
|
|
@cindex floating-point numbers, input format |
|
@cindex input format for floating-point numbers |
The format of floating point numbers recognized by the outer (aka text) |
The format of floating point numbers recognized by the outer (aka text) |
interpreter is: a signed decimal number, possibly containing a decimal |
interpreter is: a signed decimal number, possibly containing a decimal |
point (@code{.}), followed by @code{E} or @code{e}, optionally followed |
point (@code{.}), followed by @code{E} or @code{e}, optionally followed |
Line 865 value greater then 14, the @code{E} may
|
Line 966 value greater then 14, the @code{E} may
|
number will be interpreted as integer, unless it has a signed exponent |
number will be interpreted as integer, unless it has a signed exponent |
(both @code{+} and @code{-} are allowed as signs). |
(both @code{+} and @code{-} are allowed as signs). |
|
|
|
@cindex angles in trigonometric operations |
|
@cindex trigonometric operations |
Angles in floating point operations are given in radians (a full circle |
Angles in floating point operations are given in radians (a full circle |
has 2 pi radians). Note, that Gforth has a separate floating point |
has 2 pi radians). Note, that Gforth has a separate floating point |
stack, but we use the unified notation. |
stack, but we use the unified notation. |
|
|
|
@cindex floating-point arithmetic, pitfalls |
Floating point numbers have a number of unpleasant surprises for the |
Floating point numbers have a number of unpleasant surprises for the |
unwary (e.g., floating point addition is not associative) and even a few |
unwary (e.g., floating point addition is not associative) and even a few |
for the wary. You should not use them unless you know what you are doing |
for the wary. You should not use them unless you know what you are doing |
Line 911 doc-fasinh
|
Line 1015 doc-fasinh
|
doc-facosh |
doc-facosh |
doc-fatanh |
doc-fatanh |
|
|
@node Stack Manipulation, Memory access, Arithmetic, Words |
@node Stack Manipulation, Memory, Arithmetic, Words |
@section Stack Manipulation |
@section Stack Manipulation |
|
@cindex stack manipulation words |
|
|
|
@cindex floating-point stack in the standard |
Gforth has a data stack (aka parameter stack) for characters, cells, |
Gforth has a data stack (aka parameter stack) for characters, cells, |
addresses, and double cells, a floating point stack for floating point |
addresses, and double cells, a floating point stack for floating point |
numbers, a return stack for storing the return addresses of colon |
numbers, a return stack for storing the return addresses of colon |
Line 927 they work also for a unified stack model
|
Line 1033 they work also for a unified stack model
|
it. Instead, just say that your program has an environmental dependency |
it. Instead, just say that your program has an environmental dependency |
on a separate FP stack. |
on a separate FP stack. |
|
|
|
@cindex return stack and locals |
|
@cindex locals and return stack |
Also, a Forth system is allowed to keep the local variables on the |
Also, a Forth system is allowed to keep the local variables on the |
return stack. This is reasonable, as local variables usually eliminate |
return stack. This is reasonable, as local variables usually eliminate |
the need to use the return stack explicitly. So, if you want to produce |
the need to use the return stack explicitly. So, if you want to produce |
Line 944 standard document for the exact rules).
|
Line 1052 standard document for the exact rules).
|
|
|
@node Data stack, Floating point stack, Stack Manipulation, Stack Manipulation |
@node Data stack, Floating point stack, Stack Manipulation, Stack Manipulation |
@subsection Data stack |
@subsection Data stack |
|
@cindex data stack manipulation words |
|
@cindex stack manipulations words, data stack |
|
|
doc-drop |
doc-drop |
doc-nip |
doc-nip |
doc-dup |
doc-dup |
Line 965 doc-2rot
|
Line 1076 doc-2rot
|
|
|
@node Floating point stack, Return stack, Data stack, Stack Manipulation |
@node Floating point stack, Return stack, Data stack, Stack Manipulation |
@subsection Floating point stack |
@subsection Floating point stack |
|
@cindex floating-point stack manipulation words |
|
@cindex stack manipulation words, floating-point stack |
|
|
doc-fdrop |
doc-fdrop |
doc-fnip |
doc-fnip |
doc-fdup |
doc-fdup |
Line 975 doc-frot
|
Line 1089 doc-frot
|
|
|
@node Return stack, Locals stack, Floating point stack, Stack Manipulation |
@node Return stack, Locals stack, Floating point stack, Stack Manipulation |
@subsection Return stack |
@subsection Return stack |
|
@cindex return stack manipulation words |
|
@cindex stack manipulation words, return stack |
|
|
doc->r |
doc->r |
doc-r> |
doc-r> |
doc-r@ |
doc-r@ |
Line 989 doc-2rdrop
|
Line 1106 doc-2rdrop
|
|
|
@node Stack pointer manipulation, , Locals stack, Stack Manipulation |
@node Stack pointer manipulation, , Locals stack, Stack Manipulation |
@subsection Stack pointer manipulation |
@subsection Stack pointer manipulation |
|
@cindex stack pointer manipulation words |
|
|
doc-sp@ |
doc-sp@ |
doc-sp! |
doc-sp! |
doc-fp@ |
doc-fp@ |
Line 998 doc-rp!
|
Line 1117 doc-rp!
|
doc-lp@ |
doc-lp@ |
doc-lp! |
doc-lp! |
|
|
@node Memory access, Control Structures, Stack Manipulation, Words |
@node Memory, Control Structures, Stack Manipulation, Words |
@section Memory access |
@section Memory |
|
@cindex Memory words |
|
|
@menu |
@menu |
* Stack-Memory transfers:: |
* Memory Access:: |
* Address arithmetic:: |
* Address arithmetic:: |
* Memory block access:: |
* Memory Blocks:: |
@end menu |
@end menu |
|
|
@node Stack-Memory transfers, Address arithmetic, Memory access, Memory access |
@node Memory Access, Address arithmetic, Memory, Memory |
@subsection Stack-Memory transfers |
@subsection Memory Access |
|
@cindex memory access words |
|
|
doc-@ |
doc-@ |
doc-! |
doc-! |
Line 1024 doc-sf!
|
Line 1145 doc-sf!
|
doc-df@ |
doc-df@ |
doc-df! |
doc-df! |
|
|
@node Address arithmetic, Memory block access, Stack-Memory transfers, Memory access |
@node Address arithmetic, Memory Blocks, Memory Access, Memory |
@subsection Address arithmetic |
@subsection Address arithmetic |
|
@cindex address arithmetic words |
|
|
ANS Forth does not specify the sizes of the data types. Instead, it |
ANS Forth does not specify the sizes of the data types. Instead, it |
offers a number of words for computing sizes and doing address |
offers a number of words for computing sizes and doing address |
Line 1034 address units (aus); on most systems the
|
Line 1156 address units (aus); on most systems the
|
that a character may have more than one au, so @code{chars} is no noop |
that a character may have more than one au, so @code{chars} is no noop |
(on systems where it is a noop, it compiles to nothing). |
(on systems where it is a noop, it compiles to nothing). |
|
|
|
@cindex alignment of addresses for types |
ANS Forth also defines words for aligning addresses for specific |
ANS Forth also defines words for aligning addresses for specific |
addresses. Many computers require that accesses to specific data types |
types. Many computers require that accesses to specific data types |
must only occur at specific addresses; e.g., that cells may only be |
must only occur at specific addresses; e.g., that cells may only be |
accessed at addresses divisible by 4. Even if a machine allows unaligned |
accessed at addresses divisible by 4. Even if a machine allows unaligned |
accesses, it can usually perform aligned accesses faster. |
accesses, it can usually perform aligned accesses faster. |
Line 1049 an oversight, but reflects the fact that
|
Line 1172 an oversight, but reflects the fact that
|
char-aligned have no use in the standard and therefore will not be |
char-aligned have no use in the standard and therefore will not be |
created. |
created. |
|
|
|
@cindex @code{CREATE} and alignment |
The standard guarantees that addresses returned by @code{CREATE}d words |
The standard guarantees that addresses returned by @code{CREATE}d words |
are cell-aligned; in addition, Gforth guarantees that these addresses |
are cell-aligned; in addition, Gforth guarantees that these addresses |
are aligned for all purposes. |
are aligned for all purposes. |
Line 1060 doc-chars
|
Line 1184 doc-chars
|
doc-char+ |
doc-char+ |
doc-cells |
doc-cells |
doc-cell+ |
doc-cell+ |
|
doc-cell |
doc-align |
doc-align |
doc-aligned |
doc-aligned |
doc-floats |
doc-floats |
doc-float+ |
doc-float+ |
|
doc-float |
doc-falign |
doc-falign |
doc-faligned |
doc-faligned |
doc-sfloats |
doc-sfloats |
Line 1080 doc-cfalign
|
Line 1206 doc-cfalign
|
doc-cfaligned |
doc-cfaligned |
doc-address-unit-bits |
doc-address-unit-bits |
|
|
@node Memory block access, , Address arithmetic, Memory access |
@node Memory Blocks, , Address arithmetic, Memory |
@subsection Memory block access |
@subsection Memory Blocks |
|
@cindex memory block words |
|
|
doc-move |
doc-move |
doc-erase |
doc-erase |
Line 1094 doc-cmove>
|
Line 1221 doc-cmove>
|
doc-fill |
doc-fill |
doc-blank |
doc-blank |
|
|
@node Control Structures, Locals, Memory access, Words |
@node Control Structures, Locals, Memory, Words |
@section Control Structures |
@section Control Structures |
|
@cindex control structures |
|
|
Control structures in Forth cannot be used in interpret state, only in |
Control structures in Forth cannot be used in interpret state, only in |
compile state, i.e., in a colon definition. We do not like this |
compile state@footnote{More precisely, they have no interpretation |
limitation, but have not seen a satisfying way around it yet, although |
semantics (@pxref{Interpretation and Compilation Semantics})}, i.e., in |
many schemes have been proposed. |
a colon definition. We do not like this limitation, but have not seen a |
|
satisfying way around it yet, although many schemes have been proposed. |
|
|
@menu |
@menu |
* Selection:: |
* Selection:: |
Line 1113 many schemes have been proposed.
|
Line 1242 many schemes have been proposed.
|
|
|
@node Selection, Simple Loops, Control Structures, Control Structures |
@node Selection, Simple Loops, Control Structures, Control Structures |
@subsection Selection |
@subsection Selection |
|
@cindex selection control structures |
|
@cindex control structures for selection |
|
|
|
@cindex @code{IF} control structure |
@example |
@example |
@var{flag} |
@var{flag} |
IF |
IF |
Line 1155 efficient than using @code{?dup}. Defini
|
Line 1287 efficient than using @code{?dup}. Defini
|
for @code{ENDIF}, @code{?DUP-IF} and @code{?DUP-0=-IF} are provided in |
for @code{ENDIF}, @code{?DUP-IF} and @code{?DUP-0=-IF} are provided in |
@file{compat/control.fs}. |
@file{compat/control.fs}. |
|
|
|
@cindex @code{CASE} control structure |
@example |
@example |
@var{n} |
@var{n} |
CASE |
CASE |
Line 1171 but must not consume it.
|
Line 1304 but must not consume it.
|
|
|
@node Simple Loops, Counted Loops, Selection, Control Structures |
@node Simple Loops, Counted Loops, Selection, Control Structures |
@subsection Simple Loops |
@subsection Simple Loops |
|
@cindex simple loops |
|
@cindex loops without count |
|
|
|
@cindex @code{WHILE} loop |
@example |
@example |
BEGIN |
BEGIN |
@var{code1} |
@var{code1} |
Line 1182 REPEAT
|
Line 1318 REPEAT
|
@end example |
@end example |
|
|
@var{code1} is executed and @var{flag} is computed. If it is true, |
@var{code1} is executed and @var{flag} is computed. If it is true, |
@var{code2} is executed and the loop is restarted; If @var{flag} is false, execution continues after the @code{REPEAT}. |
@var{code2} is executed and the loop is restarted; If @var{flag} is |
|
false, execution continues after the @code{REPEAT}. |
|
|
|
@cindex @code{UNTIL} loop |
@example |
@example |
BEGIN |
BEGIN |
@var{code} |
@var{code} |
Line 1193 UNTIL
|
Line 1331 UNTIL
|
|
|
@var{code} is executed. The loop is restarted if @code{flag} is false. |
@var{code} is executed. The loop is restarted if @code{flag} is false. |
|
|
|
@cindex endless loop |
|
@cindex loops, endless |
@example |
@example |
BEGIN |
BEGIN |
@var{code} |
@var{code} |
Line 1203 This is an endless loop.
|
Line 1343 This is an endless loop.
|
|
|
@node Counted Loops, Arbitrary control structures, Simple Loops, Control Structures |
@node Counted Loops, Arbitrary control structures, Simple Loops, Control Structures |
@subsection Counted Loops |
@subsection Counted Loops |
|
@cindex counted loops |
|
@cindex loops, counted |
|
@cindex @code{DO} loops |
|
|
The basic counted loop is: |
The basic counted loop is: |
@example |
@example |
Line 1228 The index of the innermost loop can be a
|
Line 1371 The index of the innermost loop can be a
|
of the next loop with @code{j}, and the index of the third loop with |
of the next loop with @code{j}, and the index of the third loop with |
@code{k}. |
@code{k}. |
|
|
|
doc-i |
|
doc-j |
|
doc-k |
|
|
The loop control data are kept on the return stack, so there are some |
The loop control data are kept on the return stack, so there are some |
restrictions on mixing return stack accesses and counted loop |
restrictions on mixing return stack accesses and counted loop |
words. E.g., if you put values on the return stack outside the loop, you |
words. E.g., if you put values on the return stack outside the loop, you |
Line 1255 between @var{limit-1} and @var{limit} is
|
Line 1402 between @var{limit-1} and @var{limit} is
|
|
|
@code{4 1 +DO i . 2 +LOOP} prints @code{1 3} |
@code{4 1 +DO i . 2 +LOOP} prints @code{1 3} |
|
|
|
@cindex negative increment for counted loops |
|
@cindex counted loops with negative increment |
The behaviour of @code{@var{n} +LOOP} is peculiar when @var{n} is negative: |
The behaviour of @code{@var{n} +LOOP} is peculiar when @var{n} is negative: |
|
|
@code{-1 0 ?DO i . -1 +LOOP} prints @code{0 -1} |
@code{-1 0 ?DO i . -1 +LOOP} prints @code{0 -1} |
Line 1288 to become invalid during maintenance of
|
Line 1437 to become invalid during maintenance of
|
@code{EXIT}. @code{UNLOOP} removes the loop control parameters from the |
@code{EXIT}. @code{UNLOOP} removes the loop control parameters from the |
return stack so @code{EXIT} can get to its return address. |
return stack so @code{EXIT} can get to its return address. |
|
|
|
@cindex @code{FOR} loops |
Another counted loop is |
Another counted loop is |
@example |
@example |
@var{n} |
@var{n} |
Line 1304 loops.
|
Line 1454 loops.
|
|
|
@node Arbitrary control structures, Calls and returns, Counted Loops, Control Structures |
@node Arbitrary control structures, Calls and returns, Counted Loops, Control Structures |
@subsection Arbitrary control structures |
@subsection Arbitrary control structures |
|
@cindex control structures, user-defined |
|
|
|
@cindex control-flow stack |
ANS Forth permits and supports using control structures in a non-nested |
ANS Forth permits and supports using control structures in a non-nested |
way. Information about incomplete control structures is stored on the |
way. Information about incomplete control structures is stored on the |
control-flow stack. This stack may be implemented on the Forth data |
control-flow stack. This stack may be implemented on the Forth data |
stack, and this is what we have done in Gforth. |
stack, and this is what we have done in Gforth. |
|
|
|
@cindex @code{orig}, control-flow stack item |
|
@cindex @code{dest}, control-flow stack item |
An @i{orig} entry represents an unresolved forward branch, a @i{dest} |
An @i{orig} entry represents an unresolved forward branch, a @i{dest} |
entry represents a backward branch target. A few words are the basis for |
entry represents a backward branch target. A few words are the basis for |
building any control structure possible (except control structures that |
building any control structure possible (except control structures that |
Line 1422 necessary to define them.
|
Line 1576 necessary to define them.
|
|
|
@node Calls and returns, Exception Handling, Arbitrary control structures, Control Structures |
@node Calls and returns, Exception Handling, Arbitrary control structures, Control Structures |
@subsection Calls and returns |
@subsection Calls and returns |
|
@cindex calling a definition |
|
@cindex returning from a definition |
|
|
A definition can be called simply be writing the name of the |
A definition can be called simply be writing the name of the |
definition. When the end of the definition is reached, it returns. An |
definition. When the end of the definition is reached, it returns. An |
Line 1437 doc-;s
|
Line 1593 doc-;s
|
|
|
@node Exception Handling, , Calls and returns, Control Structures |
@node Exception Handling, , Calls and returns, Control Structures |
@subsection Exception Handling |
@subsection Exception Handling |
|
@cindex Exceptions |
|
|
doc-catch |
doc-catch |
doc-throw |
doc-throw |
|
|
@node Locals, Defining Words, Control Structures, Words |
@node Locals, Defining Words, Control Structures, Words |
@section Locals |
@section Locals |
|
@cindex locals |
|
|
Local variables can make Forth programming more enjoyable and Forth |
Local variables can make Forth programming more enjoyable and Forth |
programs easier to read. Unfortunately, the locals of ANS Forth are |
programs easier to read. Unfortunately, the locals of ANS Forth are |
Line 1462 at EuroForth '94; it is available at
|
Line 1620 at EuroForth '94; it is available at
|
|
|
@node Gforth locals, ANS Forth locals, Locals, Locals |
@node Gforth locals, ANS Forth locals, Locals, Locals |
@subsection Gforth locals |
@subsection Gforth locals |
|
@cindex Gforth locals |
|
@cindex locals, Gforth style |
|
|
Locals can be defined with |
Locals can be defined with |
|
|
Line 1494 find. However, this problem can be avoid
|
Line 1654 find. However, this problem can be avoid
|
conventions: Do not use both notations in the same program. If you do, |
conventions: Do not use both notations in the same program. If you do, |
they should be distinguished using additional means, e.g. by position. |
they should be distinguished using additional means, e.g. by position. |
|
|
|
@cindex types of locals |
|
@cindex locals types |
The name of the local may be preceded by a type specifier, e.g., |
The name of the local may be preceded by a type specifier, e.g., |
@code{F:} for a floating point value: |
@code{F:} for a floating point value: |
|
|
Line 1504 The name of the local may be preceded by
|
Line 1666 The name of the local may be preceded by
|
Ar Bi f* Ai Br f* f+ ; |
Ar Bi f* Ai Br f* f+ ; |
@end example |
@end example |
|
|
|
@cindex flavours of locals |
|
@cindex locals flavours |
|
@cindex value-flavoured locals |
|
@cindex variable-flavoured locals |
Gforth currently supports cells (@code{W:}, @code{W^}), doubles |
Gforth currently supports cells (@code{W:}, @code{W^}), doubles |
(@code{D:}, @code{D^}), floats (@code{F:}, @code{F^}) and characters |
(@code{D:}, @code{D^}), floats (@code{F:}, @code{F^}) and characters |
(@code{C:}, @code{C^}) in two flavours: a value-flavoured local (defined |
(@code{C:}, @code{C^}) in two flavours: a value-flavoured local (defined |
Line 1518 left). E.g., the standard word @code{emi
|
Line 1684 left). E.g., the standard word @code{emi
|
char* 1 type ; |
char* 1 type ; |
@end example |
@end example |
|
|
|
@cindex default type of locals |
|
@cindex locals, default type |
A local without type specifier is a @code{W:} local. Both flavours of |
A local without type specifier is a @code{W:} local. Both flavours of |
locals are initialized with values from the data or FP stack. |
locals are initialized with values from the data or FP stack. |
|
|
Line 1536 poses the following questions:
|
Line 1704 poses the following questions:
|
|
|
@node Where are locals visible by name?, How long do locals live?, Gforth locals, Gforth locals |
@node Where are locals visible by name?, How long do locals live?, Gforth locals, Gforth locals |
@subsubsection Where are locals visible by name? |
@subsubsection Where are locals visible by name? |
|
@cindex locals visibility |
|
@cindex visibility of locals |
|
@cindex scope of locals |
|
|
Basically, the answer is that locals are visible where you would expect |
Basically, the answer is that locals are visible where you would expect |
it in block-structured languages, and sometimes a little longer. If you |
it in block-structured languages, and sometimes a little longer. If you |
Line 1582 that the visibility of some locals is mo
|
Line 1753 that the visibility of some locals is mo
|
says. If @code{UNREACHABLE} is used where it should not (i.e., if you |
says. If @code{UNREACHABLE} is used where it should not (i.e., if you |
lie to the compiler), buggy code will be produced. |
lie to the compiler), buggy code will be produced. |
|
|
|
doc-unreachable |
|
|
Another problem with this rule is that at @code{BEGIN}, the compiler |
Another problem with this rule is that at @code{BEGIN}, the compiler |
does not know which locals will be visible on the incoming |
does not know which locals will be visible on the incoming |
back-edge. All problems discussed in the following are due to this |
back-edge. All problems discussed in the following are due to this |
Line 1695 REPEAT
|
Line 1868 REPEAT
|
|
|
@node How long do locals live?, Programming Style, Where are locals visible by name?, Gforth locals |
@node How long do locals live?, Programming Style, Where are locals visible by name?, Gforth locals |
@subsubsection How long do locals live? |
@subsubsection How long do locals live? |
|
@cindex locals lifetime |
|
@cindex lifetime of locals |
|
|
The right answer for the lifetime question would be: A local lives at |
The right answer for the lifetime question would be: A local lives at |
least as long as it can be accessed. For a value-flavoured local this |
least as long as it can be accessed. For a value-flavoured local this |
Line 1709 afterwards are erroneous).
|
Line 1884 afterwards are erroneous).
|
|
|
@node Programming Style, Implementation, How long do locals live?, Gforth locals |
@node Programming Style, Implementation, How long do locals live?, Gforth locals |
@subsubsection Programming Style |
@subsubsection Programming Style |
|
@cindex locals programming style |
|
@cindex programming style, locals |
|
|
The freedom to define locals anywhere has the potential to change |
The freedom to define locals anywhere has the potential to change |
programming styles dramatically. In particular, the need to use the |
programming styles dramatically. In particular, the need to use the |
Line 1729 readable. Of course, this benefit will o
|
Line 1906 readable. Of course, this benefit will o
|
programmers continue to honour the principle of factoring instead of |
programmers continue to honour the principle of factoring instead of |
using the added latitude to make the words longer. |
using the added latitude to make the words longer. |
|
|
|
@cindex single-assignment style for locals |
Using @code{TO} can and should be avoided. Without @code{TO}, |
Using @code{TO} can and should be avoided. Without @code{TO}, |
every value-flavoured local has only a single assignment and many |
every value-flavoured local has only a single assignment and many |
advantages of functional languages apply to Forth. I.e., programs are |
advantages of functional languages apply to Forth. I.e., programs are |
Line 1778 in every loop iteration.
|
Line 1956 in every loop iteration.
|
|
|
@node Implementation, , Programming Style, Gforth locals |
@node Implementation, , Programming Style, Gforth locals |
@subsubsection Implementation |
@subsubsection Implementation |
|
@cindex locals implementation |
|
@cindex implementation of locals |
|
|
|
@cindex locals stack |
Gforth uses an extra locals stack. The most compelling reason for |
Gforth uses an extra locals stack. The most compelling reason for |
this is that the return stack is not float-aligned; using an extra stack |
this is that the return stack is not float-aligned; using an extra stack |
also eliminates the problems and restrictions of using the return stack |
also eliminates the problems and restrictions of using the return stack |
Line 1814 area and @code{@}} switches it back and
|
Line 1995 area and @code{@}} switches it back and
|
initializing code. @code{W:} etc.@ are normal defining words. This |
initializing code. @code{W:} etc.@ are normal defining words. This |
special area is cleared at the start of every colon definition. |
special area is cleared at the start of every colon definition. |
|
|
|
@cindex wordlist for defining locals |
A special feature of Gforth's dictionary is used to implement the |
A special feature of Gforth's dictionary is used to implement the |
definition of locals without type specifiers: every wordlist (aka |
definition of locals without type specifiers: every wordlist (aka |
vocabulary) has its own methods for searching |
vocabulary) has its own methods for searching |
Line 1860 level to the level at the orig point, so
|
Line 2042 level to the level at the orig point, so
|
adjustment from the current level to the right level after the |
adjustment from the current level to the right level after the |
@code{THEN}. |
@code{THEN}. |
|
|
|
@cindex locals information on the control-flow stack |
|
@cindex control-flow stack items, locals information |
In a conventional Forth implementation a dest control-flow stack entry |
In a conventional Forth implementation a dest control-flow stack entry |
is just the target address and an orig entry is just the address to be |
is just the target address and an orig entry is just the address to be |
patched. Our locals implementation adds a wordlist to every orig or dest |
patched. Our locals implementation adds a wordlist to every orig or dest |
Line 1906 usually less than reclaiming this space
|
Line 2090 usually less than reclaiming this space
|
|
|
@node ANS Forth locals, , Gforth locals, Locals |
@node ANS Forth locals, , Gforth locals, Locals |
@subsection ANS Forth locals |
@subsection ANS Forth locals |
|
@cindex locals, ANS Forth style |
|
|
The ANS Forth locals wordset does not define a syntax for locals, but |
The ANS Forth locals wordset does not define a syntax for locals, but |
words that make it possible to define various syntaxes. One of the |
words that make it possible to define various syntaxes. One of the |
Line 1966 locals wordset.
|
Line 2151 locals wordset.
|
|
|
@node Defining Words, Tokens for Words, Locals, Words |
@node Defining Words, Tokens for Words, Locals, Words |
@section Defining Words |
@section Defining Words |
|
@cindex defining words |
|
|
@menu |
@menu |
* Simple Defining Words:: |
* Simple Defining Words:: |
Line 1977 locals wordset.
|
Line 2163 locals wordset.
|
|
|
@node Simple Defining Words, Colon Definitions, Defining Words, Defining Words |
@node Simple Defining Words, Colon Definitions, Defining Words, Defining Words |
@subsection Simple Defining Words |
@subsection Simple Defining Words |
|
@cindex simple defining words |
|
@cindex defining words, simple |
|
|
doc-constant |
doc-constant |
doc-2constant |
doc-2constant |
Line 1993 doc-is
|
Line 2181 doc-is
|
|
|
@node Colon Definitions, User-defined Defining Words, Simple Defining Words, Defining Words |
@node Colon Definitions, User-defined Defining Words, Simple Defining Words, Defining Words |
@subsection Colon Definitions |
@subsection Colon Definitions |
|
@cindex colon definitions |
|
|
@example |
@example |
: name ( ... -- ... ) |
: name ( ... -- ... ) |
Line 2011 doc-;
|
Line 2200 doc-;
|
|
|
@node User-defined Defining Words, Supplying names, Colon Definitions, Defining Words |
@node User-defined Defining Words, Supplying names, Colon Definitions, Defining Words |
@subsection User-defined Defining Words |
@subsection User-defined Defining Words |
|
@cindex user-defined defining words |
|
@cindex defining words, user-defined |
|
|
You can create new defining words simply by wrapping defining-time code |
You can create new defining words simply by wrapping defining-time code |
around existing defining words and putting the sequence in a colon |
around existing defining words and putting the sequence in a colon |
definition. |
definition. |
|
|
|
@cindex @code{CREATE} ... @code{DOES>} |
If you want the words defined with your defining words to behave |
If you want the words defined with your defining words to behave |
differently from words defined with standard defining words, you can |
differently from words defined with standard defining words, you can |
write your defining word like this: |
write your defining word like this: |
Line 2063 When you create a constant with @code{5
|
Line 2255 When you create a constant with @code{5
|
@code{five} with @code{,}. When @code{five} is invoked, the address of |
@code{five} with @code{,}. When @code{five} is invoked, the address of |
the body is put on the stack, and @code{@@} retrieves the value 5. |
the body is put on the stack, and @code{@@} retrieves the value 5. |
|
|
|
@cindex stack effect of @code{DOES>}-parts |
|
@cindex @code{DOES>}-parts, stack effect |
In the example above the stack comment after the @code{DOES>} specifies |
In the example above the stack comment after the @code{DOES>} specifies |
the stack effect of the defined words, not the stack effect of the |
the stack effect of the defined words, not the stack effect of the |
following code (the following code expects the address of the body on |
following code (the following code expects the address of the body on |
Line 2071 the convention that I use and recommend
|
Line 2265 the convention that I use and recommend
|
locals declarations for stack effect specification, though). |
locals declarations for stack effect specification, though). |
|
|
@subsubsection Applications of @code{CREATE..DOES>} |
@subsubsection Applications of @code{CREATE..DOES>} |
|
@cindex @code{CREATE} ... @code{DOES>}, applications |
|
|
You may wonder how to use this feature. Here are some usage patterns: |
You may wonder how to use this feature. Here are some usage patterns: |
|
|
|
@cindex factoring similar colon definitions |
When you see a sequence of code occurring several times, and you can |
When you see a sequence of code occurring several times, and you can |
identify a meaning, you will factor it out as a colon definition. When |
identify a meaning, you will factor it out as a colon definition. When |
you see similar colon definitions, you can factor them using |
you see similar colon definitions, you can factor them using |
Line 2097 DOES> ( reg-target reg-source n -- )
|
Line 2293 DOES> ( reg-target reg-source n -- )
|
1 reg-reg-imm andi, |
1 reg-reg-imm andi, |
@end example |
@end example |
|
|
|
@cindex currying |
Another view of @code{CREATE..DOES>} is to consider it as a crude way to |
Another view of @code{CREATE..DOES>} is to consider it as a crude way to |
supply a part of the parameters for a word (known as @dfn{currying} in |
supply a part of the parameters for a word (known as @dfn{currying} in |
the functional language community). E.g., @code{+} needs two |
the functional language community). E.g., @code{+} needs two |
Line 2113 DOES> ( n2 -- n1+n2 )
|
Line 2310 DOES> ( n2 -- n1+n2 )
|
@end example |
@end example |
|
|
@subsubsection The gory details of @code{CREATE..DOES>} |
@subsubsection The gory details of @code{CREATE..DOES>} |
|
@cindex @code{CREATE} ... @code{DOES>}, details |
|
|
doc-does> |
doc-does> |
|
|
|
@cindex @code{DOES>} in a separate definition |
This means that you need not use @code{CREATE} and @code{DOES>} in the |
This means that you need not use @code{CREATE} and @code{DOES>} in the |
same definition; E.g., you can put the @code{DOES>}-part in a separate |
same definition; E.g., you can put the @code{DOES>}-part in a separate |
definition. This allows us to, e.g., select among different DOES>-parts: |
definition. This allows us to, e.g., select among different DOES>-parts: |
Line 2137 DOES> ( ... -- ... )
|
Line 2336 DOES> ( ... -- ... )
|
ENDIF ; |
ENDIF ; |
@end example |
@end example |
|
|
|
@cindex @code{DOES>} in interpretation state |
In a standard program you can apply a @code{DOES>}-part only if the last |
In a standard program you can apply a @code{DOES>}-part only if the last |
word was defined with @code{CREATE}. In Gforth, the @code{DOES>}-part |
word was defined with @code{CREATE}. In Gforth, the @code{DOES>}-part |
will override the behaviour of the last word defined in any case. In a |
will override the behaviour of the last word defined in any case. In a |
Line 2164 doc->body
|
Line 2364 doc->body
|
|
|
@node Supplying names, Interpretation and Compilation Semantics, User-defined Defining Words, Defining Words |
@node Supplying names, Interpretation and Compilation Semantics, User-defined Defining Words, Defining Words |
@subsection Supplying names for the defined words |
@subsection Supplying names for the defined words |
|
@cindex names for defined words |
|
@cindex defining words, name parameter |
|
|
|
@cindex defining words, name given in a string |
By default, defining words take the names for the defined words from the |
By default, defining words take the names for the defined words from the |
input stream. Sometimes you want to supply the name from a string. You |
input stream. Sometimes you want to supply the name from a string. You |
can do this with |
can do this with |
Line 2181 is equivalent to
|
Line 2384 is equivalent to
|
create foo |
create foo |
@end example |
@end example |
|
|
|
@cindex defining words without name |
Sometimes you want to define a word without a name. You can do this with |
Sometimes you want to define a word without a name. You can do this with |
|
|
doc-noname |
doc-noname |
|
|
|
@cindex execution token of last defined word |
To make any use of the newly defined word, you need its execution |
To make any use of the newly defined word, you need its execution |
token. You can get it with |
token. You can get it with |
|
|
Line 2218 IS deferred
|
Line 2423 IS deferred
|
|
|
@node Interpretation and Compilation Semantics, , Supplying names, Defining Words |
@node Interpretation and Compilation Semantics, , Supplying names, Defining Words |
@subsection Interpretation and Compilation Semantics |
@subsection Interpretation and Compilation Semantics |
|
@cindex semantics, interpretation and compilation |
|
|
|
@cindex interpretation semantics |
The @dfn{interpretation semantics} of a word are what the text |
The @dfn{interpretation semantics} of a word are what the text |
interpreter does when it encounters the word in interpret state. It also |
interpreter does when it encounters the word in interpret state. It also |
appears in some other contexts, e.g., the execution token returned by |
appears in some other contexts, e.g., the execution token returned by |
Line 2226 appears in some other contexts, e.g., th
|
Line 2433 appears in some other contexts, e.g., th
|
@var{word} (in other words, @code{' @var{word} execute} is equivalent to |
@var{word} (in other words, @code{' @var{word} execute} is equivalent to |
interpret-state text interpretation of @code{@var{word}}). |
interpret-state text interpretation of @code{@var{word}}). |
|
|
|
@cindex compilation semantics |
The @dfn{compilation semantics} of a word are what the text interpreter |
The @dfn{compilation semantics} of a word are what the text interpreter |
does when it encounters the word in compile state. It also appears in |
does when it encounters the word in compile state. It also appears in |
other contexts, e.g, @code{POSTPONE @var{word}} compiles@footnote{In |
other contexts, e.g, @code{POSTPONE @var{word}} compiles@footnote{In |
standard terminology, ``appends to the current definition''.} the |
standard terminology, ``appends to the current definition''.} the |
compilation semantics of @var{word}. |
compilation semantics of @var{word}. |
|
|
|
@cindex execution semantics |
The standard also talks about @dfn{execution semantics}. They are used |
The standard also talks about @dfn{execution semantics}. They are used |
only for defining the interpretation and compilation semantics of many |
only for defining the interpretation and compilation semantics of many |
words. By default, the interpretation semantics of a word are to |
words. By default, the interpretation semantics of a word are to |
Line 2242 execution semantics; the default compila
|
Line 2451 execution semantics; the default compila
|
execution semantics to the execution semantics of the current |
execution semantics to the execution semantics of the current |
definition.} |
definition.} |
|
|
|
@cindex immediate words |
You can change the compilation semantics into @code{execute}ing the |
You can change the compilation semantics into @code{execute}ing the |
execution semantics with |
execution semantics with |
|
|
doc-immediate |
doc-immediate |
|
|
|
@cindex compile-only words |
You can remove the interpretation semantics of a word with |
You can remove the interpretation semantics of a word with |
|
|
doc-compile-only |
doc-compile-only |
Line 2295 the same compilation semantics as the si
|
Line 2506 the same compilation semantics as the si
|
@code{foobar}, but the implementation of the compilation semantics is |
@code{foobar}, but the implementation of the compilation semantics is |
more efficient with respect to run-time. |
more efficient with respect to run-time. |
|
|
|
@cindex state-smart words are a bad idea |
Some people try to use state-smart words to emulate the feature provided |
Some people try to use state-smart words to emulate the feature provided |
by @code{interpret/compile:} (words are state-smart if they check |
by @code{interpret/compile:} (words are state-smart if they check |
@code{STATE} during execution). E.g., they would try to code |
@code{STATE} during execution). E.g., they would try to code |
Line 2320 state, the result will not be what you e
|
Line 2532 state, the result will not be what you e
|
perform @code{foo bar}). State-smart words are a bad idea. Simply don't |
perform @code{foo bar}). State-smart words are a bad idea. Simply don't |
write them! |
write them! |
|
|
|
@cindex defining words with arbitrary semantics combinations |
It is also possible to write defining words that define words with |
It is also possible to write defining words that define words with |
arbitrary combinations of interpretation and compilation semantics (or, |
arbitrary combinations of interpretation and compilation semantics (or, |
preferably, arbitrary combinations of implementations of the default |
preferably, arbitrary combinations of implementations of the default |
Line 2371 accessing the header structure usually k
|
Line 2584 accessing the header structure usually k
|
|
|
@node Tokens for Words, Wordlists, Defining Words, Words |
@node Tokens for Words, Wordlists, Defining Words, Words |
@section Tokens for Words |
@section Tokens for Words |
|
@cindex tokens for words |
|
|
This chapter describes the creation and use of tokens that represent |
This chapter describes the creation and use of tokens that represent |
words on the stack (and in data space). |
words on the stack (and in data space). |
Line 2378 words on the stack (and in data space).
|
Line 2592 words on the stack (and in data space).
|
Named words have interpretation and compilation semantics. Unnamed words |
Named words have interpretation and compilation semantics. Unnamed words |
just have execution semantics. |
just have execution semantics. |
|
|
|
@cindex execution token |
An @dfn{execution token} represents the execution semantics of an |
An @dfn{execution token} represents the execution semantics of an |
unnamed word. An execution token occupies one cell. As explained in |
unnamed word. An execution token occupies one cell. As explained in |
section @ref{Supplying names}, the execution token of the last words |
section @ref{Supplying names}, the execution token of the last words |
Line 2390 doc-execute
|
Line 2605 doc-execute
|
You can compile the word with |
You can compile the word with |
doc-compile, |
doc-compile, |
|
|
|
@cindex code field address |
|
@cindex CFA |
In Gforth, the abstract data type @emph{execution token} is implemented |
In Gforth, the abstract data type @emph{execution token} is implemented |
as CFA (code field address). |
as CFA (code field address). |
|
|
Line 2405 by complaining about compile-only words.
|
Line 2622 by complaining about compile-only words.
|
compiling word @var{X}, use @code{COMP' @var{X} drop} or @code{[COMP'] |
compiling word @var{X}, use @code{COMP' @var{X} drop} or @code{[COMP'] |
@var{X} drop}. |
@var{X} drop}. |
|
|
|
@cindex compilation token |
The compilation semantics are represented by a @dfn{compilation token} |
The compilation semantics are represented by a @dfn{compilation token} |
consisting of two cells: @var{w xt}. The top cell @var{xt} is an |
consisting of two cells: @var{w xt}. The top cell @var{xt} is an |
execution token. The compilation semantics represented by the |
execution token. The compilation semantics represented by the |
Line 2427 token, and the @var{xt} part represents
|
Line 2645 token, and the @var{xt} part represents
|
we may introduce unusual compilation tokens in the future (e.g., |
we may introduce unusual compilation tokens in the future (e.g., |
compilation tokens representing the compilation semantics of literals). |
compilation tokens representing the compilation semantics of literals). |
|
|
|
@cindex name token |
|
@cindex name field address |
|
@cindex NFA |
Named words are also represented by the @dfn{name token}. The abstract |
Named words are also represented by the @dfn{name token}. The abstract |
data type @emph{name token} is implemented as NFA (name field address). |
data type @emph{name token} is implemented as NFA (name field address). |
|
|
Line 2450 doc-name>string
|
Line 2671 doc-name>string
|
|
|
@node Programming Tools, Assembler and Code words, Other I/O, Words |
@node Programming Tools, Assembler and Code words, Other I/O, Words |
@section Programming Tools |
@section Programming Tools |
|
@cindex programming tools |
|
|
@menu |
@menu |
* Debugging:: Simple and quick. |
* Debugging:: Simple and quick. |
Line 2458 doc-name>string
|
Line 2680 doc-name>string
|
|
|
@node Debugging, Assertions, Programming Tools, Programming Tools |
@node Debugging, Assertions, Programming Tools, Programming Tools |
@subsection Debugging |
@subsection Debugging |
|
@cindex debugging |
|
|
The simple debugging aids provided in @file{debugging.fs} |
The simple debugging aids provided in @file{debugging.fs} |
are meant to support a different style of debugging than the |
are meant to support a different style of debugging than the |
Line 2490 doc-printdebugline
|
Line 2713 doc-printdebugline
|
|
|
@node Assertions, , Debugging, Programming Tools |
@node Assertions, , Debugging, Programming Tools |
@subsection Assertions |
@subsection Assertions |
|
@cindex assertions |
|
|
It is a good idea to make your programs self-checking, in particular, if |
It is a good idea to make your programs self-checking, in particular, if |
you use an assumption (e.g., that a certain field of a data structure is |
you use an assumption (e.g., that a certain field of a data structure is |
Line 2549 probably more appropriate than an assert
|
Line 2773 probably more appropriate than an assert
|
|
|
@node Assembler and Code words, Threading Words, Programming Tools, Words |
@node Assembler and Code words, Threading Words, Programming Tools, Words |
@section Assembler and Code words |
@section Assembler and Code words |
|
@cindex assembler |
|
@cindex code words |
|
|
Gforth provides some words for defining primitives (words written in |
Gforth provides some words for defining primitives (words written in |
machine code), and for defining the the machine-code equivalent of |
machine code), and for defining the the machine-code equivalent of |
Line 2576 These words are rarely used. Therefore t
|
Line 2802 These words are rarely used. Therefore t
|
which is usually not loaded (except @code{flush-icache}, which is always |
which is usually not loaded (except @code{flush-icache}, which is always |
present). You can load them with @code{require code.fs}. |
present). You can load them with @code{require code.fs}. |
|
|
|
@cindex registers of the inner interpreter |
In the assembly code you will want to refer to the inner interpreter's |
In the assembly code you will want to refer to the inner interpreter's |
registers (e.g., the data stack pointer) and you may want to use other |
registers (e.g., the data stack pointer) and you may want to use other |
registers for temporary storage. Unfortunately, the register allocation |
registers for temporary storage. Unfortunately, the register allocation |
Line 2608 actual register allocation. E.g., if the
|
Line 2835 actual register allocation. E.g., if the
|
register @code{$17}, create an alias for this register called @code{sp}, |
register @code{$17}, create an alias for this register called @code{sp}, |
and use that in your assembly code. |
and use that in your assembly code. |
|
|
|
@cindex code words, portable |
Another option for implementing normal and defining words efficiently |
Another option for implementing normal and defining words efficiently |
is: adding the wanted functionality to the source of Gforth. For normal |
is: adding the wanted functionality to the source of Gforth. For normal |
words you just have to edit @file{primitives} (@pxref{Automatic |
words you just have to edit @file{primitives} (@pxref{Automatic |
Line 2618 defined words) may require changes in @f
|
Line 2846 defined words) may require changes in @f
|
|
|
@node Threading Words, , Assembler and Code words, Words |
@node Threading Words, , Assembler and Code words, Words |
@section Threading Words |
@section Threading Words |
|
@cindex threading words |
|
|
|
@cindex code address |
These words provide access to code addresses and other threading stuff |
These words provide access to code addresses and other threading stuff |
in Gforth (and, possibly, other interpretive Forths). It more or less |
in Gforth (and, possibly, other interpretive Forths). It more or less |
abstracts away the differences between direct and indirect threading |
abstracts away the differences between direct and indirect threading |
(and, for direct threading, the machine dependences). However, at |
(and, for direct threading, the machine dependences). However, at |
present this wordset is still inclomplete. It is also pretty low-level; |
present this wordset is still incomplete. It is also pretty low-level; |
some day it will hopefully be made unnecessary by an internals words set |
some day it will hopefully be made unnecessary by an internals wordset |
that abstracts implementation details away completely. |
that abstracts implementation details away completely. |
|
|
doc->code-address |
doc->code-address |
Line 2653 defining word.
|
Line 2883 defining word.
|
@chapter Tools |
@chapter Tools |
|
|
@menu |
@menu |
* ANS Report:: Report the words used, sorted by wordset |
* ANS Report:: Report the words used, sorted by wordset. |
@end menu |
@end menu |
|
|
See also @ref{Emacs and Gforth}. |
See also @ref{Emacs and Gforth}. |
|
|
@node ANS Report, , Tools, Tools |
@node ANS Report, , Tools, Tools |
@section @file{ans-report.fs}: Report the words used, sorted by wordset |
@section @file{ans-report.fs}: Report the words used, sorted by wordset |
|
@cindex @file{ans-report.fs} |
|
@cindex report the words used in your program |
|
@cindex words used in your program |
|
|
If you want to label a Forth program as ANS Forth Program, you must |
If you want to label a Forth program as ANS Forth Program, you must |
document which wordsets the program uses; for extension wordsets, it is |
document which wordsets the program uses; for extension wordsets, it is |
Line 2699 which wordset is the right one to specif
|
Line 2932 which wordset is the right one to specif
|
compilation semantics of @code{S"}, it is a Core word; if you also use |
compilation semantics of @code{S"}, it is a Core word; if you also use |
its interpretation semantics, it is a File word. |
its interpretation semantics, it is a File word. |
|
|
|
@c ****************************************************************** |
@node ANS conformance, Model, Tools, Top |
@node ANS conformance, Model, Tools, Top |
@chapter ANS conformance |
@chapter ANS conformance |
|
@cindex ANS conformance of Gforth |
|
|
To the best of our knowledge, Gforth is an |
To the best of our knowledge, Gforth is an |
|
|
Line 2732 ANS Forth System
|
Line 2966 ANS Forth System
|
@item providing the String Extensions word set (another easy one) |
@item providing the String Extensions word set (another easy one) |
@end itemize |
@end itemize |
|
|
|
@cindex system documentation |
In addition, ANS Forth systems are required to document certain |
In addition, ANS Forth systems are required to document certain |
implementation choices. This chapter tries to meet these |
implementation choices. This chapter tries to meet these |
requirements. In many cases it gives a way to ask the system for the |
requirements. In many cases it gives a way to ask the system for the |
Line 2762 change during the maintenance of Gforth.
|
Line 2997 change during the maintenance of Gforth.
|
@comment node-name, next, previous, up |
@comment node-name, next, previous, up |
@section The Core Words |
@section The Core Words |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex core words, system documentation |
|
@cindex system documentation, core words |
|
|
@menu |
@menu |
* core-idef:: Implementation Defined Options |
* core-idef:: Implementation Defined Options |
Line 2773 change during the maintenance of Gforth.
|
Line 3010 change during the maintenance of Gforth.
|
@node core-idef, core-ambcond, The Core Words, The Core Words |
@node core-idef, core-ambcond, The Core Words, The Core Words |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex core words, implementation-defined options |
|
@cindex implementation-defined options, core words |
|
|
@table @i |
|
|
|
|
@table @i |
@item (Cell) aligned addresses: |
@item (Cell) aligned addresses: |
|
@cindex cell-aligned addresses |
|
@cindex aligned addresses |
processor-dependent. Gforth's alignment words perform natural alignment |
processor-dependent. Gforth's alignment words perform natural alignment |
(e.g., an address aligned for a datum of size 8 is divisible by |
(e.g., an address aligned for a datum of size 8 is divisible by |
8). Unaligned accesses usually result in a @code{-23 THROW}. |
8). Unaligned accesses usually result in a @code{-23 THROW}. |
|
|
@item @code{EMIT} and non-graphic characters: |
@item @code{EMIT} and non-graphic characters: |
|
@cindex @code{EMIT} and non-graphic characters |
|
@cindex non-graphic characters and @code{EMIT} |
The character is output using the C library function (actually, macro) |
The character is output using the C library function (actually, macro) |
@code{putc}. |
@code{putc}. |
|
|
@item character editing of @code{ACCEPT} and @code{EXPECT}: |
@item character editing of @code{ACCEPT} and @code{EXPECT}: |
|
@cindex character editing of @code{ACCEPT} and @code{EXPECT} |
|
@cindex editing in @code{ACCEPT} and @code{EXPECT} |
|
@cindex @code{ACCEPT}, editing |
|
@cindex @code{EXPECT}, editing |
This is modeled on the GNU readline library (@pxref{Readline |
This is modeled on the GNU readline library (@pxref{Readline |
Interaction, , Command Line Editing, readline, The GNU Readline |
Interaction, , Command Line Editing, readline, The GNU Readline |
Library}) with Emacs-like key bindings. @kbd{Tab} deviates a little by |
Library}) with Emacs-like key bindings. @kbd{Tab} deviates a little by |
Line 2793 producing a full word completion every t
|
Line 3040 producing a full word completion every t
|
producing the common prefix of all completions). |
producing the common prefix of all completions). |
|
|
@item character set: |
@item character set: |
|
@cindex character set |
The character set of your computer and display device. Gforth is |
The character set of your computer and display device. Gforth is |
8-bit-clean (but some other component in your system may make trouble). |
8-bit-clean (but some other component in your system may make trouble). |
|
|
@item Character-aligned address requirements: |
@item Character-aligned address requirements: |
|
@cindex character-aligned address requirements |
installation-dependent. Currently a character is represented by a C |
installation-dependent. Currently a character is represented by a C |
@code{unsigned char}; in the future we might switch to @code{wchar_t} |
@code{unsigned char}; in the future we might switch to @code{wchar_t} |
(Comments on that requested). |
(Comments on that requested). |
|
|
@item character-set extensions and matching of names: |
@item character-set extensions and matching of names: |
|
@cindex character-set extensions and matching of names |
|
@cindex case sensitivity for name lookup |
|
@cindex name lookup, case sensitivity |
|
@cindex locale and case sensitivity |
Any character except the ASCII NUL charcter can be used in a |
Any character except the ASCII NUL charcter can be used in a |
name. Matching is case-insensitive (except in @code{TABLE}s. The |
name. Matching is case-insensitive (except in @code{TABLE}s). The |
matching is performed using the C function @code{strncasecmp}, whose |
matching is performed using the C function @code{strncasecmp}, whose |
function is probably influenced by the locale. E.g., the @code{C} locale |
function is probably influenced by the locale. E.g., the @code{C} locale |
does not know about accents and umlauts, so they are matched |
does not know about accents and umlauts, so they are matched |
Line 2817 are using)). Also, the locale you prefer
|
Line 3070 are using)). Also, the locale you prefer
|
operating systems. Hopefully, Unicode will solve these problems one day. |
operating systems. Hopefully, Unicode will solve these problems one day. |
|
|
@item conditions under which control characters match a space delimiter: |
@item conditions under which control characters match a space delimiter: |
|
@cindex space delimiters |
|
@cindex control characters as delimiters |
If @code{WORD} is called with the space character as a delimiter, all |
If @code{WORD} is called with the space character as a delimiter, all |
white-space characters (as identified by the C macro @code{isspace()}) |
white-space characters (as identified by the C macro @code{isspace()}) |
are delimiters. @code{PARSE}, on the other hand, treats space like other |
are delimiters. @code{PARSE}, on the other hand, treats space like other |
Line 2826 interpreter (aka text interpreter) by de
|
Line 3081 interpreter (aka text interpreter) by de
|
characters as delimiters. |
characters as delimiters. |
|
|
@item format of the control flow stack: |
@item format of the control flow stack: |
|
@cindex control flow stack, format |
The data stack is used as control flow stack. The size of a control flow |
The data stack is used as control flow stack. The size of a control flow |
stack item in cells is given by the constant @code{cs-item-size}. At the |
stack item in cells is given by the constant @code{cs-item-size}. At the |
time of this writing, an item consists of a (pointer to a) locals list |
time of this writing, an item consists of a (pointer to a) locals list |
Line 2835 item (TOS). The following tags are used:
|
Line 3091 item (TOS). The following tags are used:
|
@code{scopestart}. |
@code{scopestart}. |
|
|
@item conversion of digits > 35 |
@item conversion of digits > 35 |
|
@cindex digits > 35 |
The characters @code{[\]^_'} are the digits with the decimal value |
The characters @code{[\]^_'} are the digits with the decimal value |
36@minus{}41. There is no way to input many of the larger digits. |
36@minus{}41. There is no way to input many of the larger digits. |
|
|
@item display after input terminates in @code{ACCEPT} and @code{EXPECT}: |
@item display after input terminates in @code{ACCEPT} and @code{EXPECT}: |
|
@cindex @code{EXPECT}, display after end of input |
|
@cindex @code{ACCEPT}, display after end of input |
The cursor is moved to the end of the entered string. If the input is |
The cursor is moved to the end of the entered string. If the input is |
terminated using the @kbd{Return} key, a space is typed. |
terminated using the @kbd{Return} key, a space is typed. |
|
|
@item exception abort sequence of @code{ABORT"}: |
@item exception abort sequence of @code{ABORT"}: |
|
@cindex exception abort sequence of @code{ABORT"} |
|
@cindex @code{ABORT"}, exception abort sequence |
The error string is stored into the variable @code{"error} and a |
The error string is stored into the variable @code{"error} and a |
@code{-2 throw} is performed. |
@code{-2 throw} is performed. |
|
|
@item input line terminator: |
@item input line terminator: |
|
@cindex input line terminator |
|
@cindex line terminator on input |
|
@cindex newline charcter on input |
For interactive input, @kbd{C-m} (CR) and @kbd{C-j} (LF) terminate |
For interactive input, @kbd{C-m} (CR) and @kbd{C-j} (LF) terminate |
lines. One of these characters is typically produced when you type the |
lines. One of these characters is typically produced when you type the |
@kbd{Enter} or @kbd{Return} key. |
@kbd{Enter} or @kbd{Return} key. |
|
|
@item maximum size of a counted string: |
@item maximum size of a counted string: |
|
@cindex maximum size of a counted string |
|
@cindex counted string, maximum size |
@code{s" /counted-string" environment? drop .}. Currently 255 characters |
@code{s" /counted-string" environment? drop .}. Currently 255 characters |
on all ports, but this may change. |
on all ports, but this may change. |
|
|
@item maximum size of a parsed string: |
@item maximum size of a parsed string: |
|
@cindex maximum size of a parsed string |
|
@cindex parsed string, maximum size |
Given by the constant @code{/line}. Currently 255 characters. |
Given by the constant @code{/line}. Currently 255 characters. |
|
|
@item maximum size of a definition name, in characters: |
@item maximum size of a definition name, in characters: |
|
@cindex maximum size of a definition name, in characters |
|
@cindex name, maximum length |
31 |
31 |
|
|
@item maximum string length for @code{ENVIRONMENT?}, in characters: |
@item maximum string length for @code{ENVIRONMENT?}, in characters: |
|
@cindex maximum string length for @code{ENVIRONMENT?}, in characters |
|
@cindex @code{ENVIRONMENT?} string length, maximum |
31 |
31 |
|
|
@item method of selecting the user input device: |
@item method of selecting the user input device: |
|
@cindex user input device, method of selecting |
The user input device is the standard input. There is currently no way to |
The user input device is the standard input. There is currently no way to |
change it from within Gforth. However, the input can typically be |
change it from within Gforth. However, the input can typically be |
redirected in the command line that starts Gforth. |
redirected in the command line that starts Gforth. |
|
|
@item method of selecting the user output device: |
@item method of selecting the user output device: |
|
@cindex user output device, method of selecting |
@code{EMIT} and @code{TYPE} output to the file-id stored in the value |
@code{EMIT} and @code{TYPE} output to the file-id stored in the value |
@code{outfile-id} (@code{stdout} by default). Gforth uses buffered |
@code{outfile-id} (@code{stdout} by default). Gforth uses buffered |
output, so output on a terminal does not become visible before the next |
output, so output on a terminal does not become visible before the next |
Line 2880 the buffer overflows.
|
Line 3154 the buffer overflows.
|
What are we expected to document here? |
What are we expected to document here? |
|
|
@item number of bits in one address unit: |
@item number of bits in one address unit: |
|
@cindex number of bits in one address unit |
|
@cindex address unit, size in bits |
@code{s" address-units-bits" environment? drop .}. 8 in all current |
@code{s" address-units-bits" environment? drop .}. 8 in all current |
ports. |
ports. |
|
|
@item number representation and arithmetic: |
@item number representation and arithmetic: |
|
@cindex number representation and arithmetic |
Processor-dependent. Binary two's complement on all current ports. |
Processor-dependent. Binary two's complement on all current ports. |
|
|
@item ranges for integer types: |
@item ranges for integer types: |
|
@cindex ranges for integer types |
|
@cindex integer types, ranges |
Installation-dependent. Make environmental queries for @code{MAX-N}, |
Installation-dependent. Make environmental queries for @code{MAX-N}, |
@code{MAX-U}, @code{MAX-D} and @code{MAX-UD}. The lower bounds for |
@code{MAX-U}, @code{MAX-D} and @code{MAX-UD}. The lower bounds for |
unsigned (and positive) types is 0. The lower bound for signed types on |
unsigned (and positive) types is 0. The lower bound for signed types on |
Line 2894 two's complement and one's complement ma
|
Line 3173 two's complement and one's complement ma
|
by adding 1 to the upper bound. |
by adding 1 to the upper bound. |
|
|
@item read-only data space regions: |
@item read-only data space regions: |
|
@cindex read-only data space regions |
|
@cindex data-space, read-only regions |
The whole Forth data space is writable. |
The whole Forth data space is writable. |
|
|
@item size of buffer at @code{WORD}: |
@item size of buffer at @code{WORD}: |
|
@cindex size of buffer at @code{WORD} |
|
@cindex @code{WORD} buffer size |
@code{PAD HERE - .}. 104 characters on 32-bit machines. The buffer is |
@code{PAD HERE - .}. 104 characters on 32-bit machines. The buffer is |
shared with the pictured numeric output string. If overwriting |
shared with the pictured numeric output string. If overwriting |
@code{PAD} is acceptable, it is as large as the remaining dictionary |
@code{PAD} is acceptable, it is as large as the remaining dictionary |
Line 2904 space, although only as much can be sens
|
Line 3187 space, although only as much can be sens
|
string. |
string. |
|
|
@item size of one cell in address units: |
@item size of one cell in address units: |
|
@cindex cell size |
@code{1 cells .}. |
@code{1 cells .}. |
|
|
@item size of one character in address units: |
@item size of one character in address units: |
|
@cindex char size |
@code{1 chars .}. 1 on all current ports. |
@code{1 chars .}. 1 on all current ports. |
|
|
@item size of the keyboard terminal buffer: |
@item size of the keyboard terminal buffer: |
|
@cindex size of the keyboard terminal buffer |
|
@cindex terminal buffer, size |
Varies. You can determine the size at a specific time using @code{lp@@ |
Varies. You can determine the size at a specific time using @code{lp@@ |
tib - .}. It is shared with the locals stack and TIBs of files that |
tib - .}. It is shared with the locals stack and TIBs of files that |
include the current file. You can change the amount of space for TIBs |
include the current file. You can change the amount of space for TIBs |
Line 2917 and locals stack at Gforth startup with
|
Line 3204 and locals stack at Gforth startup with
|
@code{-l}. |
@code{-l}. |
|
|
@item size of the pictured numeric output buffer: |
@item size of the pictured numeric output buffer: |
|
@cindex size of the pictured numeric output buffer |
|
@cindex pictured numeric output buffer, size |
@code{PAD HERE - .}. 104 characters on 32-bit machines. The buffer is |
@code{PAD HERE - .}. 104 characters on 32-bit machines. The buffer is |
shared with @code{WORD}. |
shared with @code{WORD}. |
|
|
@item size of the scratch area returned by @code{PAD}: |
@item size of the scratch area returned by @code{PAD}: |
The remainder of dictionary space. You can even use the unused part of |
@cindex size of the scratch area returned by @code{PAD} |
the data stack space. The current size can be computed with @code{sp@@ |
@cindex @code{PAD} size |
pad - .}. |
The remainder of dictionary space. @code{unused pad here - - .}. |
|
|
@item system case-sensitivity characteristics: |
@item system case-sensitivity characteristics: |
|
@cindex case-sensitivity characteristics |
Dictionary searches are case insensitive (except in |
Dictionary searches are case insensitive (except in |
@code{TABLE}s). However, as explained above under @i{character-set |
@code{TABLE}s). However, as explained above under @i{character-set |
extensions}, the matching for non-ASCII characters is determined by the |
extensions}, the matching for non-ASCII characters is determined by the |
Line 2933 locale you are using. In the default @co
|
Line 3223 locale you are using. In the default @co
|
characters are matched case-sensitively. |
characters are matched case-sensitively. |
|
|
@item system prompt: |
@item system prompt: |
|
@cindex system prompt |
|
@cindex prompt |
@code{ ok} in interpret state, @code{ compiled} in compile state. |
@code{ ok} in interpret state, @code{ compiled} in compile state. |
|
|
@item division rounding: |
@item division rounding: |
|
@cindex division rounding |
installation dependent. @code{s" floored" environment? drop .}. We leave |
installation dependent. @code{s" floored" environment? drop .}. We leave |
the choice to @code{gcc} (what to use for @code{/}) and to you (whether to use |
the choice to @code{gcc} (what to use for @code{/}) and to you (whether |
@code{fm/mod}, @code{sm/rem} or simply @code{/}). |
to use @code{fm/mod}, @code{sm/rem} or simply @code{/}). |
|
|
@item values of @code{STATE} when true: |
@item values of @code{STATE} when true: |
|
@cindex @code{STATE} values |
-1. |
-1. |
|
|
@item values returned after arithmetic overflow: |
@item values returned after arithmetic overflow: |
Line 2952 fault), although a @code{-10 throw} (div
|
Line 3246 fault), although a @code{-10 throw} (div
|
appropriate. |
appropriate. |
|
|
@item whether the current definition can be found after @t{DOES>}: |
@item whether the current definition can be found after @t{DOES>}: |
|
@cindex @t{DOES>}, visibility of current definition |
No. |
No. |
|
|
@end table |
@end table |
Line 2960 No.
|
Line 3255 No.
|
@node core-ambcond, core-other, core-idef, The Core Words |
@node core-ambcond, core-other, core-idef, The Core Words |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex core words, ambiguous conditions |
|
@cindex ambiguous conditions, core words |
|
|
@table @i |
@table @i |
|
|
@item a name is neither a word nor a number: |
@item a name is neither a word nor a number: |
|
@cindex name not found |
|
@cindex Undefined word |
@code{-13 throw} (Undefined word). Actually, @code{-13 bounce}, which |
@code{-13 throw} (Undefined word). Actually, @code{-13 bounce}, which |
preserves the data and FP stack, so you don't lose more work than |
preserves the data and FP stack, so you don't lose more work than |
necessary. |
necessary. |
|
|
@item a definition name exceeds the maximum length allowed: |
@item a definition name exceeds the maximum length allowed: |
|
@cindex Word name too long |
@code{-19 throw} (Word name too long) |
@code{-19 throw} (Word name too long) |
|
|
@item addressing a region not inside the various data spaces of the forth system: |
@item addressing a region not inside the various data spaces of the forth system: |
|
@cindex Invalid memory address |
The stacks, code space and name space are accessible. Machine code space is |
The stacks, code space and name space are accessible. Machine code space is |
typically readable. Accessing other addresses gives results dependent on |
typically readable. Accessing other addresses gives results dependent on |
the operating system. On decent systems: @code{-9 throw} (Invalid memory |
the operating system. On decent systems: @code{-9 throw} (Invalid memory |
address). |
address). |
|
|
@item argument type incompatible with parameter: |
@item argument type incompatible with parameter: |
|
@cindex Argument type mismatch |
This is usually not caught. Some words perform checks, e.g., the control |
This is usually not caught. Some words perform checks, e.g., the control |
flow words, and issue a @code{ABORT"} or @code{-12 THROW} (Argument type |
flow words, and issue a @code{ABORT"} or @code{-12 THROW} (Argument type |
mismatch). |
mismatch). |
|
|
@item attempting to obtain the execution token of a word with undefined execution semantics: |
@item attempting to obtain the execution token of a word with undefined execution semantics: |
|
@cindex Interpreting a compile-only word, for @code{'} etc. |
|
@cindex execution token of words with undefined execution semantics |
@code{-14 throw} (Interpreting a compile-only word). In some cases, you |
@code{-14 throw} (Interpreting a compile-only word). In some cases, you |
get an execution token for @code{compile-only-error} (which performs a |
get an execution token for @code{compile-only-error} (which performs a |
@code{-14 throw} when executed). |
@code{-14 throw} when executed). |
|
|
@item dividing by zero: |
@item dividing by zero: |
|
@cindex dividing by zero |
|
@cindex floating point unidentified fault, integer division |
|
@cindex divide by zero |
typically results in a @code{-55 throw} (floating point unidentified |
typically results in a @code{-55 throw} (floating point unidentified |
fault), although a @code{-10 throw} (divide by zero) would be more |
fault), although a @code{-10 throw} (divide by zero) would be more |
appropriate. |
appropriate. |
|
|
@item insufficient data stack or return stack space: |
@item insufficient data stack or return stack space: |
Not checked. This typically results in mysterious illegal memory |
@cindex insufficient data stack or return stack space |
accesses, producing @code{-9 throw} (Invalid memory address) or |
@cindex stack overflow |
@code{-23 throw} (Address alignment exception). |
@cindex Address alignment exception, stack overflow |
|
@cindex Invalid memory address, stack overflow |
|
Depending on the operating system, the installation, and the invocation |
|
of Gforth, this is either checked by the memory management hardware, or |
|
it is not checked. If it is checked, you typically get a @code{-9 throw} |
|
(Invalid memory address) as soon as the overflow happens. If it is not |
|
check, overflows typically result in mysterious illegal memory accesses, |
|
producing @code{-9 throw} (Invalid memory address) or @code{-23 throw} |
|
(Address alignment exception); they might also destroy the internal data |
|
structure of @code{ALLOCATE} and friends, resulting in various errors in |
|
these words. |
|
|
@item insufficient space for loop control parameters: |
@item insufficient space for loop control parameters: |
|
@cindex insufficient space for loop control parameters |
like other return stack overflows. |
like other return stack overflows. |
|
|
@item insufficient space in the dictionary: |
@item insufficient space in the dictionary: |
Not checked. Similar results as stack overflows. However, typically the |
@cindex insufficient space in the dictionary |
error appears at a different place when one inserts or removes code. |
@cindex dictionary overflow |
|
Depending on the operating system, the installation, and the invocation |
|
of Gforth, this is either checked by the memory management hardware, or |
|
it is not checked. Similar results as stack overflows. However, |
|
typically the error appears at a different place when one inserts or |
|
removes code. Also, the @code{THROW} does not relieve the situation (it |
|
does for stack overflows). |
|
|
@item interpreting a word with undefined interpretation semantics: |
@item interpreting a word with undefined interpretation semantics: |
For some words, we defined interpretation semantics. For the others: |
@cindex interpreting a word with undefined interpretation semantics |
@code{-14 throw} (Interpreting a compile-only word). |
@cindex Interpreting a compile-only word |
|
For some words, we have defined interpretation semantics. For the |
|
others: @code{-14 throw} (Interpreting a compile-only word). |
|
|
@item modifying the contents of the input buffer or a string literal: |
@item modifying the contents of the input buffer or a string literal: |
|
@cindex modifying the contents of the input buffer or a string literal |
These are located in writable memory and can be modified. |
These are located in writable memory and can be modified. |
|
|
@item overflow of the pictured numeric output string: |
@item overflow of the pictured numeric output string: |
Not checked. |
@cindex overflow of the pictured numeric output string |
|
@cindex pictured numeric output string, overflow |
|
Not checked. Runs into the dictionary and destroys it (at least, |
|
partially). |
|
|
@item parsed string overflow: |
@item parsed string overflow: |
|
@cindex parsed string overflow |
@code{PARSE} cannot overflow. @code{WORD} does not check for overflow. |
@code{PARSE} cannot overflow. @code{WORD} does not check for overflow. |
|
|
@item producing a result out of range: |
@item producing a result out of range: |
|
@cindex result out of range |
On two's complement machines, arithmetic is performed modulo |
On two's complement machines, arithmetic is performed modulo |
2**bits-per-cell for single arithmetic and 4**bits-per-cell for double |
2**bits-per-cell for single arithmetic and 4**bits-per-cell for double |
arithmetic (with appropriate mapping for signed types). Division by zero |
arithmetic (with appropriate mapping for signed types). Division by zero |
Line 3027 appropriate. @code{convert} and @code{>n
|
Line 3359 appropriate. @code{convert} and @code{>n
|
silently. |
silently. |
|
|
@item reading from an empty data or return stack: |
@item reading from an empty data or return stack: |
|
@cindex stack empty |
|
@cindex stack underflow |
The data stack is checked by the outer (aka text) interpreter after |
The data stack is checked by the outer (aka text) interpreter after |
every word executed. If it has underflowed, a @code{-4 throw} (Stack |
every word executed. If it has underflowed, a @code{-4 throw} (Stack |
underflow) is performed. Apart from that, the stacks are not checked and |
underflow) is performed. Apart from that, stacks may be checked or not, |
underflows can result in similar behaviour as overflows (of adjacent |
depending on operating system, installation, and invocation. The |
stacks). |
consequences of stack underflows are similar to the consequences of |
|
stack overflows. Note that even if the system uses checking (through the |
|
MMU), your program may have to underflow by a significant number of |
|
stack items to trigger the reaction (the reason for this is that the |
|
MMU, and therefore the checking, works with a page-size granularity). |
|
|
@item unexpected end of the input buffer, resulting in an attempt to use a zero-length string as a name: |
@item unexpected end of the input buffer, resulting in an attempt to use a zero-length string as a name: |
|
@cindex unexpected end of the input buffer |
|
@cindex zero-length string as a name |
|
@cindex Attempt to use zero-length string as a name |
@code{Create} and its descendants perform a @code{-16 throw} (Attempt to |
@code{Create} and its descendants perform a @code{-16 throw} (Attempt to |
use zero-length string as a name). Words like @code{'} probably will not |
use zero-length string as a name). Words like @code{'} probably will not |
find what they search. Note that it is possible to create zero-length |
find what they search. Note that it is possible to create zero-length |
names with @code{nextname} (should it not?). |
names with @code{nextname} (should it not?). |
|
|
@item @code{>IN} greater than input buffer: |
@item @code{>IN} greater than input buffer: |
|
@cindex @code{>IN} greater than input buffer |
The next invocation of a parsing word returns a string with length 0. |
The next invocation of a parsing word returns a string with length 0. |
|
|
@item @code{RECURSE} appears after @code{DOES>}: |
@item @code{RECURSE} appears after @code{DOES>}: |
|
@cindex @code{RECURSE} appears after @code{DOES>} |
Compiles a recursive call to the defining word, not to the defined word. |
Compiles a recursive call to the defining word, not to the defined word. |
|
|
@item argument input source different than current input source for @code{RESTORE-INPUT}: |
@item argument input source different than current input source for @code{RESTORE-INPUT}: |
|
@cindex argument input source different than current input source for @code{RESTORE-INPUT} |
|
@cindex Argument type mismatch, @code{RESTORE-INPUT} |
|
@cindex @code{RESTORE-INPUT}, Argument type mismatch |
@code{-12 THROW}. Note that, once an input file is closed (e.g., because |
@code{-12 THROW}. Note that, once an input file is closed (e.g., because |
the end of the file was reached), its source-id may be |
the end of the file was reached), its source-id may be |
reused. Therefore, restoring an input source specification referencing a |
reused. Therefore, restoring an input source specification referencing a |
Line 3056 In the future, Gforth may be able to res
|
Line 3402 In the future, Gforth may be able to res
|
from other than the current input source. |
from other than the current input source. |
|
|
@item data space containing definitions gets de-allocated: |
@item data space containing definitions gets de-allocated: |
|
@cindex data space containing definitions gets de-allocated |
Deallocation with @code{allot} is not checked. This typically results in |
Deallocation with @code{allot} is not checked. This typically results in |
memory access faults or execution of illegal instructions. |
memory access faults or execution of illegal instructions. |
|
|
@item data space read/write with incorrect alignment: |
@item data space read/write with incorrect alignment: |
|
@cindex data space read/write with incorrect alignment |
|
@cindex alignment faults |
|
@cindex Address alignment exception |
Processor-dependent. Typically results in a @code{-23 throw} (Address |
Processor-dependent. Typically results in a @code{-23 throw} (Address |
alignment exception). Under Linux on a 486 or later processor with |
alignment exception). Under Linux on a 486 or later processor with |
alignment turned on, incorrect alignment results in a @code{-9 throw} |
alignment turned on, incorrect alignment results in a @code{-9 throw} |
Line 3067 alignment turned on, incorrect alignment
|
Line 3417 alignment turned on, incorrect alignment
|
alignment restrictions that do not report them. |
alignment restrictions that do not report them. |
|
|
@item data space pointer not properly aligned, @code{,}, @code{C,}: |
@item data space pointer not properly aligned, @code{,}, @code{C,}: |
|
@cindex data space pointer not properly aligned, @code{,}, @code{C,} |
Like other alignment errors. |
Like other alignment errors. |
|
|
@item less than u+2 stack items (@code{PICK} and @code{ROLL}): |
@item less than u+2 stack items (@code{PICK} and @code{ROLL}): |
Not checked. May cause an illegal memory access. |
Like other stack underflows. |
|
|
@item loop control parameters not available: |
@item loop control parameters not available: |
|
@cindex loop control parameters not available |
Not checked. The counted loop words simply assume that the top of return |
Not checked. The counted loop words simply assume that the top of return |
stack items are loop control parameters and behave accordingly. |
stack items are loop control parameters and behave accordingly. |
|
|
@item most recent definition does not have a name (@code{IMMEDIATE}): |
@item most recent definition does not have a name (@code{IMMEDIATE}): |
|
@cindex most recent definition does not have a name (@code{IMMEDIATE}) |
|
@cindex last word was headerless |
@code{abort" last word was headerless"}. |
@code{abort" last word was headerless"}. |
|
|
@item name not defined by @code{VALUE} used by @code{TO}: |
@item name not defined by @code{VALUE} used by @code{TO}: |
@code{-32 throw} (Invalid name argument) (unless name was defined by |
@cindex name not defined by @code{VALUE} used by @code{TO} |
@code{CONSTANT}; then it just changes the constant). |
@cindex @code{TO} on non-@code{VALUE}s |
|
@cindex Invalid name argument, @code{TO} |
|
@code{-32 throw} (Invalid name argument) (unless name is a local or was |
|
defined by @code{CONSTANT}; in the latter case it just changes the constant). |
|
|
@item name not found (@code{'}, @code{POSTPONE}, @code{[']}, @code{[COMPILE]}): |
@item name not found (@code{'}, @code{POSTPONE}, @code{[']}, @code{[COMPILE]}): |
|
@cindex name not found (@code{'}, @code{POSTPONE}, @code{[']}, @code{[COMPILE]}) |
|
@cindex Undefined word, @code{'}, @code{POSTPONE}, @code{[']}, @code{[COMPILE]} |
@code{-13 throw} (Undefined word) |
@code{-13 throw} (Undefined word) |
|
|
@item parameters are not of the same type (@code{DO}, @code{?DO}, @code{WITHIN}): |
@item parameters are not of the same type (@code{DO}, @code{?DO}, @code{WITHIN}): |
|
@cindex parameters are not of the same type (@code{DO}, @code{?DO}, @code{WITHIN}) |
Gforth behaves as if they were of the same type. I.e., you can predict |
Gforth behaves as if they were of the same type. I.e., you can predict |
the behaviour by interpreting all parameters as, e.g., signed. |
the behaviour by interpreting all parameters as, e.g., signed. |
|
|
@item @code{POSTPONE} or @code{[COMPILE]} applied to @code{TO}: |
@item @code{POSTPONE} or @code{[COMPILE]} applied to @code{TO}: |
|
@cindex @code{POSTPONE} or @code{[COMPILE]} applied to @code{TO} |
Assume @code{: X POSTPONE TO ; IMMEDIATE}. @code{X} performs the |
Assume @code{: X POSTPONE TO ; IMMEDIATE}. @code{X} performs the |
compilation semantics of @code{TO}. |
compilation semantics of @code{TO}. |
|
|
@item String longer than a counted string returned by @code{WORD}: |
@item String longer than a counted string returned by @code{WORD}: |
|
@cindex String longer than a counted string returned by @code{WORD} |
|
@cindex @code{WORD}, string overflow |
Not checked. The string will be ok, but the count will, of course, |
Not checked. The string will be ok, but the count will, of course, |
contain only the least significant bits of the length. |
contain only the least significant bits of the length. |
|
|
@item u greater than or equal to the number of bits in a cell (@code{LSHIFT}, @code{RSHIFT}): |
@item u greater than or equal to the number of bits in a cell (@code{LSHIFT}, @code{RSHIFT}): |
|
@cindex @code{LSHIFT}, large shift counts |
|
@cindex @code{RSHIFT}, large shift counts |
Processor-dependent. Typical behaviours are returning 0 and using only |
Processor-dependent. Typical behaviours are returning 0 and using only |
the low bits of the shift count. |
the low bits of the shift count. |
|
|
@item word not defined via @code{CREATE}: |
@item word not defined via @code{CREATE}: |
|
@cindex @code{>BODY} of non-@code{CREATE}d words |
@code{>BODY} produces the PFA of the word no matter how it was defined. |
@code{>BODY} produces the PFA of the word no matter how it was defined. |
|
|
|
@cindex @code{DOES>} of non-@code{CREATE}d words |
@code{DOES>} changes the execution semantics of the last defined word no |
@code{DOES>} changes the execution semantics of the last defined word no |
matter how it was defined. E.g., @code{CONSTANT DOES>} is equivalent to |
matter how it was defined. E.g., @code{CONSTANT DOES>} is equivalent to |
@code{CREATE , DOES>}. |
@code{CREATE , DOES>}. |
Line 3119 Not checked. As usual, you can expect me
|
Line 3486 Not checked. As usual, you can expect me
|
@node core-other, , core-ambcond, The Core Words |
@node core-other, , core-ambcond, The Core Words |
@subsection Other system documentation |
@subsection Other system documentation |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex other system documentation, core words |
|
@cindex core words, other system documentation |
|
|
@table @i |
@table @i |
|
|
@item nonstandard words using @code{PAD}: |
@item nonstandard words using @code{PAD}: |
|
@cindex @code{PAD} use by nonstandard words |
None. |
None. |
|
|
@item operator's terminal facilities available: |
@item operator's terminal facilities available: |
|
@cindex operator's terminal facilities available |
After processing the command line, Gforth goes into interactive mode, |
After processing the command line, Gforth goes into interactive mode, |
and you can give commands to Gforth interactively. The actual facilities |
and you can give commands to Gforth interactively. The actual facilities |
available depend on how you invoke Gforth. |
available depend on how you invoke Gforth. |
|
|
@item program data space available: |
@item program data space available: |
|
@cindex program data space available |
|
@cindex data space available |
@code{UNUSED .} gives the remaining dictionary space. The total |
@code{UNUSED .} gives the remaining dictionary space. The total |
dictionary space can be specified with the @code{-m} switch |
dictionary space can be specified with the @code{-m} switch |
(@pxref{Invocation}) when Gforth starts up. |
(@pxref{Invoking Gforth}) when Gforth starts up. |
|
|
@item return stack space available: |
@item return stack space available: |
|
@cindex return stack space available |
You can compute the total return stack space in cells with |
You can compute the total return stack space in cells with |
@code{s" RETURN-STACK-CELLS" environment? drop .}. You can specify it at |
@code{s" RETURN-STACK-CELLS" environment? drop .}. You can specify it at |
startup time with the @code{-r} switch (@pxref{Invocation}). |
startup time with the @code{-r} switch (@pxref{Invoking Gforth}). |
|
|
@item stack space available: |
@item stack space available: |
|
@cindex stack space available |
You can compute the total data stack space in cells with |
You can compute the total data stack space in cells with |
@code{s" STACK-CELLS" environment? drop .}. You can specify it at |
@code{s" STACK-CELLS" environment? drop .}. You can specify it at |
startup time with the @code{-d} switch (@pxref{Invocation}). |
startup time with the @code{-d} switch (@pxref{Invoking Gforth}). |
|
|
@item system dictionary space required, in address units: |
@item system dictionary space required, in address units: |
|
@cindex system dictionary space required, in address units |
Type @code{here forthstart - .} after startup. At the time of this |
Type @code{here forthstart - .} after startup. At the time of this |
writing, this gives 80080 (bytes) on a 32-bit system. |
writing, this gives 80080 (bytes) on a 32-bit system. |
@end table |
@end table |
Line 3155 writing, this gives 80080 (bytes) on a 3
|
Line 3530 writing, this gives 80080 (bytes) on a 3
|
@node The optional Block word set, The optional Double Number word set, The Core Words, ANS conformance |
@node The optional Block word set, The optional Double Number word set, The Core Words, ANS conformance |
@section The optional Block word set |
@section The optional Block word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, block words |
|
@cindex block words, system documentation |
|
|
@menu |
@menu |
* block-idef:: Implementation Defined Options |
* block-idef:: Implementation Defined Options |
* block-ambcond:: Ambiguous Conditions |
* block-ambcond:: Ambiguous Conditions |
* block-other:: Other System Documentation |
* block-other:: Other System Documentation |
@end menu |
@end menu |
Line 3167 writing, this gives 80080 (bytes) on a 3
|
Line 3544 writing, this gives 80080 (bytes) on a 3
|
@node block-idef, block-ambcond, The optional Block word set, The optional Block word set |
@node block-idef, block-ambcond, The optional Block word set, The optional Block word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, block words |
|
@cindex block words, implementation-defined options |
|
|
@table @i |
@table @i |
|
|
@item the format for display by @code{LIST}: |
@item the format for display by @code{LIST}: |
|
@cindex @code{LIST} display format |
First the screen number is displayed, then 16 lines of 64 characters, |
First the screen number is displayed, then 16 lines of 64 characters, |
each line preceded by the line number. |
each line preceded by the line number. |
|
|
@item the length of a line affected by @code{\}: |
@item the length of a line affected by @code{\}: |
|
@cindex length of a line affected by @code{\} |
|
@cindex @code{\}, line length in blocks |
64 characters. |
64 characters. |
@end table |
@end table |
|
|
Line 3183 each line preceded by the line number.
|
Line 3564 each line preceded by the line number.
|
@node block-ambcond, block-other, block-idef, The optional Block word set |
@node block-ambcond, block-other, block-idef, The optional Block word set |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex block words, ambiguous conditions |
|
@cindex ambiguous conditions, block words |
|
|
@table @i |
@table @i |
|
|
@item correct block read was not possible: |
@item correct block read was not possible: |
|
@cindex block read not possible |
Typically results in a @code{throw} of some OS-derived value (between |
Typically results in a @code{throw} of some OS-derived value (between |
-512 and -2048). If the blocks file was just not long enough, blanks are |
-512 and -2048). If the blocks file was just not long enough, blanks are |
supplied for the missing portion. |
supplied for the missing portion. |
|
|
@item I/O exception in block transfer: |
@item I/O exception in block transfer: |
|
@cindex I/O exception in block transfer |
|
@cindex block transfer, I/O exception |
Typically results in a @code{throw} of some OS-derived value (between |
Typically results in a @code{throw} of some OS-derived value (between |
-512 and -2048). |
-512 and -2048). |
|
|
@item invalid block number: |
@item invalid block number: |
|
@cindex invalid block number |
|
@cindex block number invalid |
@code{-35 throw} (Invalid block number) |
@code{-35 throw} (Invalid block number) |
|
|
@item a program directly alters the contents of @code{BLK}: |
@item a program directly alters the contents of @code{BLK}: |
|
@cindex @code{BLK}, altering @code{BLK} |
The input stream is switched to that other block, at the same |
The input stream is switched to that other block, at the same |
position. If the storing to @code{BLK} happens when interpreting |
position. If the storing to @code{BLK} happens when interpreting |
non-block input, the system will get quite confused when the block ends. |
non-block input, the system will get quite confused when the block ends. |
|
|
@item no current block buffer for @code{UPDATE}: |
@item no current block buffer for @code{UPDATE}: |
|
@cindex @code{UPDATE}, no current block buffer |
@code{UPDATE} has no effect. |
@code{UPDATE} has no effect. |
|
|
@end table |
@end table |
|
|
|
|
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
@node block-other, , block-ambcond, The optional Block word set |
@node block-other, , block-ambcond, The optional Block word set |
@subsection Other system documentation |
@subsection Other system documentation |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex other system documentation, block words |
|
@cindex block words, other system documentation |
|
|
@table @i |
@table @i |
|
|
@item any restrictions a multiprogramming system places on the use of buffer addresses: |
@item any restrictions a multiprogramming system places on the use of buffer addresses: |
No restrictions (yet). |
No restrictions (yet). |
|
|
Line 3229 depends on your disk space.
|
Line 3618 depends on your disk space.
|
@node The optional Double Number word set, The optional Exception word set, The optional Block word set, ANS conformance |
@node The optional Double Number word set, The optional Exception word set, The optional Block word set, ANS conformance |
@section The optional Double Number word set |
@section The optional Double Number word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, double words |
|
@cindex double words, system documentation |
|
|
@menu |
@menu |
* double-ambcond:: Ambiguous Conditions |
* double-ambcond:: Ambiguous Conditions |
Line 3239 depends on your disk space.
|
Line 3630 depends on your disk space.
|
@node double-ambcond, , The optional Double Number word set, The optional Double Number word set |
@node double-ambcond, , The optional Double Number word set, The optional Double Number word set |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex double words, ambiguous conditions |
|
@cindex ambiguous conditions, double words |
|
|
@table @i |
@table @i |
|
|
@item @var{d} outside of range of @var{n} in @code{D>S}: |
@item @var{d} outside of range of @var{n} in @code{D>S}: |
|
@cindex @code{D>S}, @var{d} out of range of @var{n} |
The least significant cell of @var{d} is produced. |
The least significant cell of @var{d} is produced. |
|
|
@end table |
@end table |
Line 3252 The least significant cell of @var{d} is
|
Line 3645 The least significant cell of @var{d} is
|
@node The optional Exception word set, The optional Facility word set, The optional Double Number word set, ANS conformance |
@node The optional Exception word set, The optional Facility word set, The optional Double Number word set, ANS conformance |
@section The optional Exception word set |
@section The optional Exception word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, exception words |
|
@cindex exception words, system documentation |
|
|
@menu |
@menu |
* exception-idef:: Implementation Defined Options |
* exception-idef:: Implementation Defined Options |
Line 3262 The least significant cell of @var{d} is
|
Line 3657 The least significant cell of @var{d} is
|
@node exception-idef, , The optional Exception word set, The optional Exception word set |
@node exception-idef, , The optional Exception word set, The optional Exception word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, exception words |
|
@cindex exception words, implementation-defined options |
|
|
@table @i |
@table @i |
@item @code{THROW}-codes used in the system: |
@item @code{THROW}-codes used in the system: |
The codes -256@minus{}-511 are used for reporting signals (see |
@cindex @code{THROW}-codes used in the system |
@file{errore.fs}). The codes -512@minus{}-2047 are used for OS errors |
The codes -256@minus{}-511 are used for reporting signals. The mapping |
(for file and memory allocation operations). The mapping from OS error |
from OS signal numbers to throw codes is -256@minus{}@var{signal}. The |
numbers to throw code is -512@minus{}@code{errno}. One side effect of |
codes -512@minus{}-2047 are used for OS errors (for file and memory |
this mapping is that undefined OS errors produce a message with a |
allocation operations). The mapping from OS error numbers to throw codes |
strange number; e.g., @code{-1000 THROW} results in @code{Unknown error |
is -512@minus{}@code{errno}. One side effect of this mapping is that |
488} on my system. |
undefined OS errors produce a message with a strange number; e.g., |
|
@code{-1000 THROW} results in @code{Unknown error 488} on my system. |
@end table |
@end table |
|
|
@c ===================================================================== |
@c ===================================================================== |
@node The optional Facility word set, The optional File-Access word set, The optional Exception word set, ANS conformance |
@node The optional Facility word set, The optional File-Access word set, The optional Exception word set, ANS conformance |
@section The optional Facility word set |
@section The optional Facility word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, facility words |
|
@cindex facility words, system documentation |
|
|
@menu |
@menu |
* facility-idef:: Implementation Defined Options |
* facility-idef:: Implementation Defined Options |
Line 3289 strange number; e.g., @code{-1000 THROW}
|
Line 3689 strange number; e.g., @code{-1000 THROW}
|
@node facility-idef, facility-ambcond, The optional Facility word set, The optional Facility word set |
@node facility-idef, facility-ambcond, The optional Facility word set, The optional Facility word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, facility words |
|
@cindex facility words, implementation-defined options |
|
|
@table @i |
@table @i |
|
|
@item encoding of keyboard events (@code{EKEY}): |
@item encoding of keyboard events (@code{EKEY}): |
|
@cindex keyboard events, encoding in @code{EKEY} |
|
@cindex @code{EKEY}, encoding of keyboard events |
Not yet implemented. |
Not yet implemented. |
|
|
@item duration of a system clock tick |
@item duration of a system clock tick: |
|
@cindex duration of a system clock tick |
|
@cindex clock tick duration |
System dependent. With respect to @code{MS}, the time is specified in |
System dependent. With respect to @code{MS}, the time is specified in |
microseconds. How well the OS and the hardware implement this, is |
microseconds. How well the OS and the hardware implement this, is |
another question. |
another question. |
|
|
@item repeatability to be expected from the execution of @code{MS}: |
@item repeatability to be expected from the execution of @code{MS}: |
|
@cindex repeatability to be expected from the execution of @code{MS} |
|
@cindex @code{MS}, repeatability to be expected |
System dependent. On Unix, a lot depends on load. If the system is |
System dependent. On Unix, a lot depends on load. If the system is |
lightly loaded, and the delay is short enough that Gforth does not get |
lightly loaded, and the delay is short enough that Gforth does not get |
swapped out, the performance should be acceptable. Under MS-DOS and |
swapped out, the performance should be acceptable. Under MS-DOS and |
Line 3313 other single-tasking systems, it should
|
Line 3720 other single-tasking systems, it should
|
@node facility-ambcond, , facility-idef, The optional Facility word set |
@node facility-ambcond, , facility-idef, The optional Facility word set |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex facility words, ambiguous conditions |
|
@cindex ambiguous conditions, facility words |
|
|
@table @i |
@table @i |
|
|
@item @code{AT-XY} can't be performed on user output device: |
@item @code{AT-XY} can't be performed on user output device: |
|
@cindex @code{AT-XY} can't be performed on user output device |
Largely terminal dependent. No range checks are done on the arguments. |
Largely terminal dependent. No range checks are done on the arguments. |
No errors are reported. You may see some garbage appearing, you may see |
No errors are reported. You may see some garbage appearing, you may see |
simply nothing happen. |
simply nothing happen. |
Line 3328 simply nothing happen.
|
Line 3737 simply nothing happen.
|
@node The optional File-Access word set, The optional Floating-Point word set, The optional Facility word set, ANS conformance |
@node The optional File-Access word set, The optional Floating-Point word set, The optional Facility word set, ANS conformance |
@section The optional File-Access word set |
@section The optional File-Access word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, file words |
|
@cindex file words, system documentation |
|
|
@menu |
@menu |
* file-idef:: Implementation Defined Options |
* file-idef:: Implementation Defined Options |
* file-ambcond:: Ambiguous Conditions |
* file-ambcond:: Ambiguous Conditions |
@end menu |
@end menu |
|
|
|
|
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
@node file-idef, file-ambcond, The optional File-Access word set, The optional File-Access word set |
@node file-idef, file-ambcond, The optional File-Access word set, The optional File-Access word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, file words |
|
@cindex file words, implementation-defined options |
|
|
@table @i |
@table @i |
|
@item file access methods used: |
@item File access methods used: |
@cindex file access methods used |
@code{R/O}, @code{R/W} and @code{BIN} work as you would |
@code{R/O}, @code{R/W} and @code{BIN} work as you would |
expect. @code{W/O} translates into the C file opening mode @code{w} (or |
expect. @code{W/O} translates into the C file opening mode @code{w} (or |
@code{wb}): The file is cleared, if it exists, and created, if it does |
@code{wb}): The file is cleared, if it exists, and created, if it does |
not (both with @code{open-file} and @code{create-file}). Under Unix |
not (with both @code{open-file} and @code{create-file}). Under Unix |
@code{create-file} creates a file with 666 permissions modified by your |
@code{create-file} creates a file with 666 permissions modified by your |
umask. |
umask. |
|
|
@item file exceptions: |
@item file exceptions: |
|
@cindex file exceptions |
The file words do not raise exceptions (except, perhaps, memory access |
The file words do not raise exceptions (except, perhaps, memory access |
faults when you pass illegal addresses or file-ids). |
faults when you pass illegal addresses or file-ids). |
|
|
@item file line terminator: |
@item file line terminator: |
|
@cindex file line terminator |
System-dependent. Gforth uses C's newline character as line |
System-dependent. Gforth uses C's newline character as line |
terminator. What the actual character code(s) of this are is |
terminator. What the actual character code(s) of this are is |
system-dependent. |
system-dependent. |
|
|
@item file name format |
@item file name format: |
|
@cindex file name format |
System dependent. Gforth just uses the file name format of your OS. |
System dependent. Gforth just uses the file name format of your OS. |
|
|
@item information returned by @code{FILE-STATUS}: |
@item information returned by @code{FILE-STATUS}: |
|
@cindex @code{FILE-STATUS}, returned information |
@code{FILE-STATUS} returns the most powerful file access mode allowed |
@code{FILE-STATUS} returns the most powerful file access mode allowed |
for the file: Either @code{R/O}, @code{W/O} or @code{R/W}. If the file |
for the file: Either @code{R/O}, @code{W/O} or @code{R/W}. If the file |
cannot be accessed, @code{R/O BIN} is returned. @code{BIN} is applicable |
cannot be accessed, @code{R/O BIN} is returned. @code{BIN} is applicable |
along with the returned mode. |
along with the returned mode. |
|
|
@item input file state after an exception when including source: |
@item input file state after an exception when including source: |
|
@cindex exception when including source |
All files that are left via the exception are closed. |
All files that are left via the exception are closed. |
|
|
@item @var{ior} values and meaning: |
@item @var{ior} values and meaning: |
|
@cindex @var{ior} values and meaning |
The @var{ior}s returned by the file and memory allocation words are |
The @var{ior}s returned by the file and memory allocation words are |
intended as throw codes. They typically are in the range |
intended as throw codes. They typically are in the range |
-512@minus{}-2047 of OS errors. The mapping from OS error numbers to |
-512@minus{}-2047 of OS errors. The mapping from OS error numbers to |
@var{ior}s is -512@minus{}@var{errno}. |
@var{ior}s is -512@minus{}@var{errno}. |
|
|
@item maximum depth of file input nesting: |
@item maximum depth of file input nesting: |
|
@cindex maximum depth of file input nesting |
|
@cindex file input nesting, maximum depth |
limited by the amount of return stack, locals/TIB stack, and the number |
limited by the amount of return stack, locals/TIB stack, and the number |
of open files available. This should not give you troubles. |
of open files available. This should not give you troubles. |
|
|
@item maximum size of input line: |
@item maximum size of input line: |
|
@cindex maximum size of input line |
|
@cindex input line size, maximum |
@code{/line}. Currently 255. |
@code{/line}. Currently 255. |
|
|
@item methods of mapping block ranges to files: |
@item methods of mapping block ranges to files: |
|
@cindex mapping block ranges to files |
|
@cindex files containing blocks |
|
@cindex blocks in files |
By default, blocks are accessed in the file @file{blocks.fb} in the |
By default, blocks are accessed in the file @file{blocks.fb} in the |
current working directory. The file can be switched with @code{USE}. |
current working directory. The file can be switched with @code{USE}. |
|
|
@item number of string buffers provided by @code{S"}: |
@item number of string buffers provided by @code{S"}: |
|
@cindex @code{S"}, number of string buffers |
1 |
1 |
|
|
@item size of string buffer used by @code{S"}: |
@item size of string buffer used by @code{S"}: |
|
@cindex @code{S"}, size of string buffer |
@code{/line}. currently 255. |
@code{/line}. currently 255. |
|
|
@end table |
@end table |
Line 3400 current working directory. The file can
|
Line 3827 current working directory. The file can
|
@node file-ambcond, , file-idef, The optional File-Access word set |
@node file-ambcond, , file-idef, The optional File-Access word set |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex file words, ambiguous conditions |
|
@cindex ambiguous conditions, file words |
|
|
@table @i |
@table @i |
|
@item attempting to position a file outside its boundaries: |
@item attempting to position a file outside it's boundaries: |
@cindex @code{REPOSITION-FILE}, outside the file's boundaries |
@code{REPOSITION-FILE} is performed as usual: Afterwards, |
@code{REPOSITION-FILE} is performed as usual: Afterwards, |
@code{FILE-POSITION} returns the value given to @code{REPOSITION-FILE}. |
@code{FILE-POSITION} returns the value given to @code{REPOSITION-FILE}. |
|
|
@item attempting to read from file positions not yet written: |
@item attempting to read from file positions not yet written: |
|
@cindex reading from file positions not yet written |
End-of-file, i.e., zero characters are read and no error is reported. |
End-of-file, i.e., zero characters are read and no error is reported. |
|
|
@item @var{file-id} is invalid (@code{INCLUDE-FILE}): |
@item @var{file-id} is invalid (@code{INCLUDE-FILE}): |
|
@cindex @code{INCLUDE-FILE}, @var{file-id} is invalid |
An appropriate exception may be thrown, but a memory fault or other |
An appropriate exception may be thrown, but a memory fault or other |
problem is more probable. |
problem is more probable. |
|
|
@item I/O exception reading or closing @var{file-id} (@code{include-file}, @code{included}): |
@item I/O exception reading or closing @var{file-id} (@code{INCLUDE-FILE}, @code{INCLUDED}): |
|
@cindex @code{INCLUDE-FILE}, I/O exception reading or closing @var{file-id} |
|
@cindex @code{INCLUDED}, I/O exception reading or closing @var{file-id} |
The @var{ior} produced by the operation, that discovered the problem, is |
The @var{ior} produced by the operation, that discovered the problem, is |
thrown. |
thrown. |
|
|
@item named file cannot be opened (@code{included}): |
@item named file cannot be opened (@code{INCLUDED}): |
|
@cindex @code{INCLUDED}, named file cannot be opened |
The @var{ior} produced by @code{open-file} is thrown. |
The @var{ior} produced by @code{open-file} is thrown. |
|
|
@item requesting an unmapped block number: |
@item requesting an unmapped block number: |
|
@cindex unmapped block numbers |
There are no unmapped legal block numbers. On some operating systems, |
There are no unmapped legal block numbers. On some operating systems, |
writing a block with a large number may overflow the file system and |
writing a block with a large number may overflow the file system and |
have an error message as consequence. |
have an error message as consequence. |
|
|
@item using @code{source-id} when @code{blk} is non-zero: |
@item using @code{source-id} when @code{blk} is non-zero: |
|
@cindex @code{SOURCE-ID}, behaviour when @code{BLK} is non-zero |
@code{source-id} performs its function. Typically it will give the id of |
@code{source-id} performs its function. Typically it will give the id of |
the source which loaded the block. (Better ideas?) |
the source which loaded the block. (Better ideas?) |
|
|
Line 3437 the source which loaded the block. (Bett
|
Line 3873 the source which loaded the block. (Bett
|
@node The optional Floating-Point word set, The optional Locals word set, The optional File-Access word set, ANS conformance |
@node The optional Floating-Point word set, The optional Locals word set, The optional File-Access word set, ANS conformance |
@section The optional Floating-Point word set |
@section The optional Floating-Point word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, floating-point words |
|
@cindex floating-point words, system documentation |
|
|
@menu |
@menu |
* floating-idef:: Implementation Defined Options |
* floating-idef:: Implementation Defined Options |
Line 3448 the source which loaded the block. (Bett
|
Line 3886 the source which loaded the block. (Bett
|
@node floating-idef, floating-ambcond, The optional Floating-Point word set, The optional Floating-Point word set |
@node floating-idef, floating-ambcond, The optional Floating-Point word set, The optional Floating-Point word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, floating-point words |
|
@cindex floating-point words, implementation-defined options |
|
|
@table @i |
@table @i |
|
|
@item format and range of floating point numbers: |
@item format and range of floating point numbers: |
|
@cindex format and range of floating point numbers |
|
@cindex floating point numbers, format and range |
System-dependent; the @code{double} type of C. |
System-dependent; the @code{double} type of C. |
|
|
@item results of @code{REPRESENT} when @var{float} is out of range: |
@item results of @code{REPRESENT} when @var{float} is out of range: |
|
@cindex @code{REPRESENT}, results when @var{float} is out of range |
System dependent; @code{REPRESENT} is implemented using the C library |
System dependent; @code{REPRESENT} is implemented using the C library |
function @code{ecvt()} and inherits its behaviour in this respect. |
function @code{ecvt()} and inherits its behaviour in this respect. |
|
|
@item rounding or truncation of floating-point numbers: |
@item rounding or truncation of floating-point numbers: |
|
@cindex rounding of floating-point numbers |
|
@cindex truncation of floating-point numbers |
|
@cindex floating-point numbers, rounding or truncation |
System dependent; the rounding behaviour is inherited from the hosting C |
System dependent; the rounding behaviour is inherited from the hosting C |
compiler. IEEE-FP-based (i.e., most) systems by default round to |
compiler. IEEE-FP-based (i.e., most) systems by default round to |
nearest, and break ties by rounding to even (i.e., such that the last |
nearest, and break ties by rounding to even (i.e., such that the last |
bit of the mantissa is 0). |
bit of the mantissa is 0). |
|
|
@item size of floating-point stack: |
@item size of floating-point stack: |
|
@cindex floating-point stack size |
@code{s" FLOATING-STACK" environment? drop .} gives the total size of |
@code{s" FLOATING-STACK" environment? drop .} gives the total size of |
the floating-point stack (in floats). You can specify this on startup |
the floating-point stack (in floats). You can specify this on startup |
with the command-line option @code{-f} (@pxref{Invocation}). |
with the command-line option @code{-f} (@pxref{Invoking Gforth}). |
|
|
@item width of floating-point stack: |
@item width of floating-point stack: |
|
@cindex floating-point stack width |
@code{1 floats}. |
@code{1 floats}. |
|
|
@end table |
@end table |
Line 3479 with the command-line option @code{-f} (
|
Line 3926 with the command-line option @code{-f} (
|
@node floating-ambcond, , floating-idef, The optional Floating-Point word set |
@node floating-ambcond, , floating-idef, The optional Floating-Point word set |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex floating-point words, ambiguous conditions |
|
@cindex ambiguous conditions, floating-point words |
|
|
@table @i |
@table @i |
|
|
@item @code{df@@} or @code{df!} used with an address that is not double-float aligned: |
@item @code{df@@} or @code{df!} used with an address that is not double-float aligned: |
|
@cindex @code{df@@} or @code{df!} used with an address that is not double-float aligned |
System-dependent. Typically results in a @code{-23 THROW} like other |
System-dependent. Typically results in a @code{-23 THROW} like other |
alignment violations. |
alignment violations. |
|
|
@item @code{f@@} or @code{f!} used with an address that is not float aligned: |
@item @code{f@@} or @code{f!} used with an address that is not float aligned: |
|
@cindex @code{f@@} used with an address that is not float aligned |
|
@cindex @code{f!} used with an address that is not float aligned |
System-dependent. Typically results in a @code{-23 THROW} like other |
System-dependent. Typically results in a @code{-23 THROW} like other |
alignment violations. |
alignment violations. |
|
|
@item Floating-point result out of range: |
@item floating-point result out of range: |
|
@cindex floating-point result out of range |
System-dependent. Can result in a @code{-55 THROW} (Floating-point |
System-dependent. Can result in a @code{-55 THROW} (Floating-point |
unidentified fault), or can produce a special value representing, e.g., |
unidentified fault), or can produce a special value representing, e.g., |
Infinity. |
Infinity. |
|
|
@item @code{sf@@} or @code{sf!} used with an address that is not single-float aligned: |
@item @code{sf@@} or @code{sf!} used with an address that is not single-float aligned: |
|
@cindex @code{sf@@} or @code{sf!} used with an address that is not single-float aligned |
System-dependent. Typically results in an alignment fault like other |
System-dependent. Typically results in an alignment fault like other |
alignment violations. |
alignment violations. |
|
|
@item BASE is not decimal (@code{REPRESENT}, @code{F.}, @code{FE.}, @code{FS.}): |
@item @code{BASE} is not decimal (@code{REPRESENT}, @code{F.}, @code{FE.}, @code{FS.}): |
|
@cindex @code{BASE} is not decimal (@code{REPRESENT}, @code{F.}, @code{FE.}, @code{FS.}) |
The floating-point number is converted into decimal nonetheless. |
The floating-point number is converted into decimal nonetheless. |
|
|
@item Both arguments are equal to zero (@code{FATAN2}): |
@item Both arguments are equal to zero (@code{FATAN2}): |
|
@cindex @code{FATAN2}, both arguments are equal to zero |
System-dependent. @code{FATAN2} is implemented using the C library |
System-dependent. @code{FATAN2} is implemented using the C library |
function @code{atan2()}. |
function @code{atan2()}. |
|
|
@item Using ftan on an argument @var{r1} where cos(@var{r1}) is zero: |
@item Using @code{FTAN} on an argument @var{r1} where cos(@var{r1}) is zero: |
|
@cindex @code{FTAN} on an argument @var{r1} where cos(@var{r1}) is zero |
System-dependent. Anyway, typically the cos of @var{r1} will not be zero |
System-dependent. Anyway, typically the cos of @var{r1} will not be zero |
because of small errors and the tan will be a very large (or very small) |
because of small errors and the tan will be a very large (or very small) |
but finite number. |
but finite number. |
|
|
@item @var{d} cannot be presented precisely as a float in @code{D>F}: |
@item @var{d} cannot be presented precisely as a float in @code{D>F}: |
|
@cindex @code{D>F}, @var{d} cannot be presented precisely as a float |
The result is rounded to the nearest float. |
The result is rounded to the nearest float. |
|
|
@item dividing by zero: |
@item dividing by zero: |
|
@cindex dividing by zero, floating-point |
|
@cindex floating-point dividing by zero |
|
@cindex floating-point unidentified fault, FP divide-by-zero |
@code{-55 throw} (Floating-point unidentified fault) |
@code{-55 throw} (Floating-point unidentified fault) |
|
|
@item exponent too big for conversion (@code{DF!}, @code{DF@@}, @code{SF!}, @code{SF@@}): |
@item exponent too big for conversion (@code{DF!}, @code{DF@@}, @code{SF!}, @code{SF@@}): |
|
@cindex exponent too big for conversion (@code{DF!}, @code{DF@@}, @code{SF!}, @code{SF@@}) |
System dependent. On IEEE-FP based systems the number is converted into |
System dependent. On IEEE-FP based systems the number is converted into |
an infinity. |
an infinity. |
|
|
@item @var{float}<1 (@code{facosh}): |
@item @var{float}<1 (@code{FACOSH}): |
|
@cindex @code{FACOSH}, @var{float}<1 |
|
@cindex floating-point unidentified fault, @code{FACOSH} |
@code{-55 throw} (Floating-point unidentified fault) |
@code{-55 throw} (Floating-point unidentified fault) |
|
|
@item @var{float}=<-1 (@code{flnp1}): |
@item @var{float}=<-1 (@code{FLNP1}): |
|
@cindex @code{FLNP1}, @var{float}=<-1 |
|
@cindex floating-point unidentified fault, @code{FLNP1} |
@code{-55 throw} (Floating-point unidentified fault). On IEEE-FP systems |
@code{-55 throw} (Floating-point unidentified fault). On IEEE-FP systems |
negative infinity is typically produced for @var{float}=-1. |
negative infinity is typically produced for @var{float}=-1. |
|
|
@item @var{float}=<0 (@code{fln}, @code{flog}): |
@item @var{float}=<0 (@code{FLN}, @code{FLOG}): |
|
@cindex @code{FLN}, @var{float}=<0 |
|
@cindex @code{FLOG}, @var{float}=<0 |
|
@cindex floating-point unidentified fault, @code{FLN} or @code{FLOG} |
@code{-55 throw} (Floating-point unidentified fault). On IEEE-FP systems |
@code{-55 throw} (Floating-point unidentified fault). On IEEE-FP systems |
negative infinity is typically produced for @var{float}=0. |
negative infinity is typically produced for @var{float}=0. |
|
|
@item @var{float}<0 (@code{fasinh}, @code{fsqrt}): |
@item @var{float}<0 (@code{FASINH}, @code{FSQRT}): |
|
@cindex @code{FASINH}, @var{float}<0 |
|
@cindex @code{FSQRT}, @var{float}<0 |
|
@cindex floating-point unidentified fault, @code{FASINH} or @code{FSQRT} |
@code{-55 throw} (Floating-point unidentified fault). @code{fasinh} |
@code{-55 throw} (Floating-point unidentified fault). @code{fasinh} |
produces values for these inputs on my Linux box (Bug in the C library?) |
produces values for these inputs on my Linux box (Bug in the C library?) |
|
|
@item |@var{float}|>1 (@code{facos}, @code{fasin}, @code{fatanh}): |
@item |@var{float}|>1 (@code{FACOS}, @code{FASIN}, @code{FATANH}): |
|
@cindex @code{FACOS}, |@var{float}|>1 |
|
@cindex @code{FASIN}, |@var{float}|>1 |
|
@cindex @code{FATANH}, |@var{float}|>1 |
|
@cindex floating-point unidentified fault, @code{FACOS}, @code{FASIN} or @code{FATANH} |
@code{-55 throw} (Floating-point unidentified fault). |
@code{-55 throw} (Floating-point unidentified fault). |
|
|
@item integer part of float cannot be represented by @var{d} in @code{f>d}: |
@item integer part of float cannot be represented by @var{d} in @code{F>D}: |
|
@cindex @code{F>D}, integer part of float cannot be represented by @var{d} |
|
@cindex floating-point unidentified fault, @code{F>D} |
@code{-55 throw} (Floating-point unidentified fault). |
@code{-55 throw} (Floating-point unidentified fault). |
|
|
@item string larger than pictured numeric output area (@code{f.}, @code{fe.}, @code{fs.}): |
@item string larger than pictured numeric output area (@code{f.}, @code{fe.}, @code{fs.}): |
|
@cindex string larger than pictured numeric output area (@code{f.}, @code{fe.}, @code{fs.}) |
This does not happen. |
This does not happen. |
@end table |
@end table |
|
|
|
|
|
|
@c ===================================================================== |
@c ===================================================================== |
@node The optional Locals word set, The optional Memory-Allocation word set, The optional Floating-Point word set, ANS conformance |
@node The optional Locals word set, The optional Memory-Allocation word set, The optional Floating-Point word set, ANS conformance |
@section The optional Locals word set |
@section The optional Locals word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, locals words |
|
@cindex locals words, system documentation |
|
|
@menu |
@menu |
* locals-idef:: Implementation Defined Options |
* locals-idef:: Implementation Defined Options |
Line 3563 This does not happen.
|
Line 4041 This does not happen.
|
@node locals-idef, locals-ambcond, The optional Locals word set, The optional Locals word set |
@node locals-idef, locals-ambcond, The optional Locals word set, The optional Locals word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, locals words |
|
@cindex locals words, implementation-defined options |
|
|
@table @i |
@table @i |
|
|
@item maximum number of locals in a definition: |
@item maximum number of locals in a definition: |
|
@cindex maximum number of locals in a definition |
|
@cindex locals, maximum number in a definition |
@code{s" #locals" environment? drop .}. Currently 15. This is a lower |
@code{s" #locals" environment? drop .}. Currently 15. This is a lower |
bound, e.g., on a 32-bit machine there can be 41 locals of up to 8 |
bound, e.g., on a 32-bit machine there can be 41 locals of up to 8 |
characters. The number of locals in a definition is bounded by the size |
characters. The number of locals in a definition is bounded by the size |
Line 3579 of locals-buffer, which contains the nam
|
Line 4060 of locals-buffer, which contains the nam
|
@node locals-ambcond, , locals-idef, The optional Locals word set |
@node locals-ambcond, , locals-idef, The optional Locals word set |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex locals words, ambiguous conditions |
|
@cindex ambiguous conditions, locals words |
|
|
@table @i |
@table @i |
|
|
@item executing a named local in interpretation state: |
@item executing a named local in interpretation state: |
@code{-14 throw} (Interpreting a compile-only word). |
@cindex local in interpretation state |
|
@cindex Interpreting a compile-only word, for a local |
|
Locals have no interpretation semantics. If you try to perform the |
|
interpretation semantics, you will get a @code{-14 throw} somewhere |
|
(Interpreting a compile-only word). If you perform the compilation |
|
semantics, the locals access will be compiled (irrespective of state). |
|
|
@item @var{name} not defined by @code{VALUE} or @code{(LOCAL)} (@code{TO}): |
@item @var{name} not defined by @code{VALUE} or @code{(LOCAL)} (@code{TO}): |
|
@cindex name not defined by @code{VALUE} or @code{(LOCAL)} used by @code{TO} |
|
@cindex @code{TO} on non-@code{VALUE}s and non-locals |
|
@cindex Invalid name argument, @code{TO} |
@code{-32 throw} (Invalid name argument) |
@code{-32 throw} (Invalid name argument) |
|
|
@end table |
@end table |
Line 3595 of locals-buffer, which contains the nam
|
Line 4085 of locals-buffer, which contains the nam
|
@node The optional Memory-Allocation word set, The optional Programming-Tools word set, The optional Locals word set, ANS conformance |
@node The optional Memory-Allocation word set, The optional Programming-Tools word set, The optional Locals word set, ANS conformance |
@section The optional Memory-Allocation word set |
@section The optional Memory-Allocation word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, memory-allocation words |
|
@cindex memory-allocation words, system documentation |
|
|
@menu |
@menu |
* memory-idef:: Implementation Defined Options |
* memory-idef:: Implementation Defined Options |
Line 3605 of locals-buffer, which contains the nam
|
Line 4097 of locals-buffer, which contains the nam
|
@node memory-idef, , The optional Memory-Allocation word set, The optional Memory-Allocation word set |
@node memory-idef, , The optional Memory-Allocation word set, The optional Memory-Allocation word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, memory-allocation words |
|
@cindex memory-allocation words, implementation-defined options |
|
|
@table @i |
@table @i |
|
|
@item values and meaning of @var{ior}: |
@item values and meaning of @var{ior}: |
|
@cindex @var{ior} values and meaning |
The @var{ior}s returned by the file and memory allocation words are |
The @var{ior}s returned by the file and memory allocation words are |
intended as throw codes. They typically are in the range |
intended as throw codes. They typically are in the range |
-512@minus{}-2047 of OS errors. The mapping from OS error numbers to |
-512@minus{}-2047 of OS errors. The mapping from OS error numbers to |
Line 3620 intended as throw codes. They typically
|
Line 4114 intended as throw codes. They typically
|
@node The optional Programming-Tools word set, The optional Search-Order word set, The optional Memory-Allocation word set, ANS conformance |
@node The optional Programming-Tools word set, The optional Search-Order word set, The optional Memory-Allocation word set, ANS conformance |
@section The optional Programming-Tools word set |
@section The optional Programming-Tools word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, programming-tools words |
|
@cindex programming-tools words, system documentation |
|
|
@menu |
@menu |
* programming-idef:: Implementation Defined Options |
* programming-idef:: Implementation Defined Options |
Line 3631 intended as throw codes. They typically
|
Line 4127 intended as throw codes. They typically
|
@node programming-idef, programming-ambcond, The optional Programming-Tools word set, The optional Programming-Tools word set |
@node programming-idef, programming-ambcond, The optional Programming-Tools word set, The optional Programming-Tools word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, programming-tools words |
|
@cindex programming-tools words, implementation-defined options |
|
|
@table @i |
@table @i |
|
@item ending sequence for input following @code{;CODE} and @code{CODE}: |
@item ending sequence for input following @code{;code} and @code{code}: |
@cindex @code{;CODE} ending sequence |
@code{end-code} |
@cindex @code{CODE} ending sequence |
|
@code{END-CODE} |
@item manner of processing input following @code{;code} and @code{code}: |
|
The @code{assembler} vocabulary is pushed on the search order stack, and |
@item manner of processing input following @code{;CODE} and @code{CODE}: |
|
@cindex @code{;CODE}, processing input |
|
@cindex @code{CODE}, processing input |
|
The @code{ASSEMBLER} vocabulary is pushed on the search order stack, and |
the input is processed by the text interpreter, (starting) in interpret |
the input is processed by the text interpreter, (starting) in interpret |
state. |
state. |
|
|
@item search order capability for @code{EDITOR} and @code{ASSEMBLER}: |
@item search order capability for @code{EDITOR} and @code{ASSEMBLER}: |
|
@cindex @code{ASSEMBLER}, search order capability |
The ANS Forth search order word set. |
The ANS Forth search order word set. |
|
|
@item source and format of display by @code{SEE}: |
@item source and format of display by @code{SEE}: |
|
@cindex @code{SEE}, source and format of output |
The source for @code{see} is the intermediate code used by the inner |
The source for @code{see} is the intermediate code used by the inner |
interpreter. The current @code{see} tries to output Forth source code |
interpreter. The current @code{see} tries to output Forth source code |
as well as possible. |
as well as possible. |
Line 3656 as well as possible.
|
Line 4159 as well as possible.
|
@node programming-ambcond, , programming-idef, The optional Programming-Tools word set |
@node programming-ambcond, , programming-idef, The optional Programming-Tools word set |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex programming-tools words, ambiguous conditions |
|
@cindex ambiguous conditions, programming-tools words |
|
|
@table @i |
@table @i |
|
|
@item deleting the compilation wordlist (@code{FORGET}): |
@item deleting the compilation wordlist (@code{FORGET}): |
|
@cindex @code{FORGET}, deleting the compilation wordlist |
Not implemented (yet). |
Not implemented (yet). |
|
|
@item fewer than @var{u}+1 items on the control flow stack (@code{CS-PICK}, @code{CS-ROLL}): |
@item fewer than @var{u}+1 items on the control flow stack (@code{CS-PICK}, @code{CS-ROLL}): |
|
@cindex @code{CS-PICK}, fewer than @var{u}+1 items on the control flow stack |
|
@cindex @code{CS-ROLL}, fewer than @var{u}+1 items on the control flow stack |
|
@cindex control-flow stack underflow |
This typically results in an @code{abort"} with a descriptive error |
This typically results in an @code{abort"} with a descriptive error |
message (may change into a @code{-22 throw} (Control structure mismatch) |
message (may change into a @code{-22 throw} (Control structure mismatch) |
in the future). You may also get a memory access error. If you are |
in the future). You may also get a memory access error. If you are |
unlucky, this ambiguous condition is not caught. |
unlucky, this ambiguous condition is not caught. |
|
|
@item @var{name} can't be found (@code{forget}): |
@item @var{name} can't be found (@code{FORGET}): |
|
@cindex @code{FORGET}, @var{name} can't be found |
Not implemented (yet). |
Not implemented (yet). |
|
|
@item @var{name} not defined via @code{CREATE}: |
@item @var{name} not defined via @code{CREATE}: |
@code{;code} behaves like @code{DOES>} in this respect, i.e., it changes |
@cindex @code{;CODE}, @var{name} not defined via @code{CREATE} |
|
@code{;CODE} behaves like @code{DOES>} in this respect, i.e., it changes |
the execution semantics of the last defined word no matter how it was |
the execution semantics of the last defined word no matter how it was |
defined. |
defined. |
|
|
@item @code{POSTPONE} applied to @code{[IF]}: |
@item @code{POSTPONE} applied to @code{[IF]}: |
|
@cindex @code{POSTPONE} applied to @code{[IF]} |
|
@cindex @code{[IF]} and @code{POSTPONE} |
After defining @code{: X POSTPONE [IF] ; IMMEDIATE}. @code{X} is |
After defining @code{: X POSTPONE [IF] ; IMMEDIATE}. @code{X} is |
equivalent to @code{[IF]}. |
equivalent to @code{[IF]}. |
|
|
@item reaching the end of the input source before matching @code{[ELSE]} or @code{[THEN]}: |
@item reaching the end of the input source before matching @code{[ELSE]} or @code{[THEN]}: |
|
@cindex @code{[IF]}, end of the input source before matching @code{[ELSE]} or @code{[THEN]} |
Continue in the same state of conditional compilation in the next outer |
Continue in the same state of conditional compilation in the next outer |
input source. Currently there is no warning to the user about this. |
input source. Currently there is no warning to the user about this. |
|
|
@item removing a needed definition (@code{FORGET}): |
@item removing a needed definition (@code{FORGET}): |
|
@cindex @code{FORGET}, removing a needed definition |
Not implemented (yet). |
Not implemented (yet). |
|
|
@end table |
@end table |
Line 3694 Not implemented (yet).
|
Line 4209 Not implemented (yet).
|
@node The optional Search-Order word set, , The optional Programming-Tools word set, ANS conformance |
@node The optional Search-Order word set, , The optional Programming-Tools word set, ANS conformance |
@section The optional Search-Order word set |
@section The optional Search-Order word set |
@c ===================================================================== |
@c ===================================================================== |
|
@cindex system documentation, search-order words |
|
@cindex search-order words, system documentation |
|
|
@menu |
@menu |
* search-idef:: Implementation Defined Options |
* search-idef:: Implementation Defined Options |
Line 3705 Not implemented (yet).
|
Line 4222 Not implemented (yet).
|
@node search-idef, search-ambcond, The optional Search-Order word set, The optional Search-Order word set |
@node search-idef, search-ambcond, The optional Search-Order word set, The optional Search-Order word set |
@subsection Implementation Defined Options |
@subsection Implementation Defined Options |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex implementation-defined options, search-order words |
|
@cindex search-order words, implementation-defined options |
|
|
@table @i |
@table @i |
|
|
@item maximum number of word lists in search order: |
@item maximum number of word lists in search order: |
|
@cindex maximum number of word lists in search order |
|
@cindex search order, maximum depth |
@code{s" wordlists" environment? drop .}. Currently 16. |
@code{s" wordlists" environment? drop .}. Currently 16. |
|
|
@item minimum search order: |
@item minimum search order: |
|
@cindex minimum search order |
|
@cindex search order, minimum |
@code{root root}. |
@code{root root}. |
|
|
@end table |
@end table |
Line 3720 Not implemented (yet).
|
Line 4242 Not implemented (yet).
|
@node search-ambcond, , search-idef, The optional Search-Order word set |
@node search-ambcond, , search-idef, The optional Search-Order word set |
@subsection Ambiguous conditions |
@subsection Ambiguous conditions |
@c --------------------------------------------------------------------- |
@c --------------------------------------------------------------------- |
|
@cindex search-order words, ambiguous conditions |
|
@cindex ambiguous conditions, search-order words |
|
|
@table @i |
@table @i |
|
|
@item changing the compilation wordlist (during compilation): |
@item changing the compilation wordlist (during compilation): |
|
@cindex changing the compilation wordlist (during compilation) |
|
@cindex compilation wordlist, change before definition ends |
The word is entered into the wordlist that was the compilation wordlist |
The word is entered into the wordlist that was the compilation wordlist |
at the start of the definition. Any changes to the name field (e.g., |
at the start of the definition. Any changes to the name field (e.g., |
@code{immediate}) or the code field (e.g., when executing @code{DOES>}) |
@code{immediate}) or the code field (e.g., when executing @code{DOES>}) |
Line 3731 are applied to the latest defined word (
|
Line 4256 are applied to the latest defined word (
|
@code{lastxt}), if possible, irrespective of the compilation wordlist. |
@code{lastxt}), if possible, irrespective of the compilation wordlist. |
|
|
@item search order empty (@code{previous}): |
@item search order empty (@code{previous}): |
|
@cindex @code{previous}, search order empty |
|
@cindex Vocstack empty, @code{previous} |
@code{abort" Vocstack empty"}. |
@code{abort" Vocstack empty"}. |
|
|
@item too many word lists in search order (@code{also}): |
@item too many word lists in search order (@code{also}): |
|
@cindex @code{also}, too many word lists in search order |
|
@cindex Vocstack full, @code{also} |
@code{abort" Vocstack full"}. |
@code{abort" Vocstack full"}. |
|
|
@end table |
@end table |
|
|
|
@c *************************************************************** |
@node Model, Integrating Gforth, ANS conformance, Top |
@node Model, Integrating Gforth, ANS conformance, Top |
@chapter Model |
@chapter Model |
|
|
This chapter has yet to be written. It will contain information, on |
This chapter has yet to be written. It will contain information, on |
which internal structures you can rely. |
which internal structures you can rely. |
|
|
|
@c *************************************************************** |
@node Integrating Gforth, Emacs and Gforth, Model, Top |
@node Integrating Gforth, Emacs and Gforth, Model, Top |
@chapter Integrating Gforth into C programs |
@chapter Integrating Gforth into C programs |
|
|
Line 3794 Signals?
|
Line 4325 Signals?
|
|
|
Accessing the Stacks |
Accessing the Stacks |
|
|
@node Emacs and Gforth, Internals, Integrating Gforth, Top |
@node Emacs and Gforth, Image Files, Integrating Gforth, Top |
@chapter Emacs and Gforth |
@chapter Emacs and Gforth |
|
@cindex Emacs and Gforth |
|
|
|
@cindex @file{gforth.el} |
|
@cindex @file{forth.el} |
|
@cindex Rydqvist, Goran |
|
@cindex comment editing commands |
|
@cindex @code{\}, editing with Emacs |
|
@cindex debug tracer editing commands |
|
@cindex @code{~~}, removal with Emacs |
|
@cindex Forth mode in Emacs |
Gforth comes with @file{gforth.el}, an improved version of |
Gforth comes with @file{gforth.el}, an improved version of |
@file{forth.el} by Goran Rydqvist (included in the TILE package). The |
@file{forth.el} by Goran Rydqvist (included in the TILE package). The |
improvements are a better (but still not perfect) handling of |
improvements are a better (but still not perfect) handling of |
Line 3807 stuff I do not use alone, even though so
|
Line 4347 stuff I do not use alone, even though so
|
TILE. To get a description of these features, enter Forth mode and type |
TILE. To get a description of these features, enter Forth mode and type |
@kbd{C-h m}. |
@kbd{C-h m}. |
|
|
|
@cindex source location of error or debugging output in Emacs |
|
@cindex error output, finding the source location in Emacs |
|
@cindex debugging output, finding the source location in Emacs |
In addition, Gforth supports Emacs quite well: The source code locations |
In addition, Gforth supports Emacs quite well: The source code locations |
given in error messages, debugging output (from @code{~~}) and failed |
given in error messages, debugging output (from @code{~~}) and failed |
assertion messages are in the right format for Emacs' compilation mode |
assertion messages are in the right format for Emacs' compilation mode |
Line 3815 Manual}) so the source location correspo
|
Line 4358 Manual}) so the source location correspo
|
message is only a few keystrokes away (@kbd{C-x `} for the next error, |
message is only a few keystrokes away (@kbd{C-x `} for the next error, |
@kbd{C-c C-c} for the error under the cursor). |
@kbd{C-c C-c} for the error under the cursor). |
|
|
|
@cindex @file{TAGS} file |
|
@cindex @file{etags.fs} |
|
@cindex viewing the source of a word in Emacs |
Also, if you @code{include} @file{etags.fs}, a new @file{TAGS} file |
Also, if you @code{include} @file{etags.fs}, a new @file{TAGS} file |
(@pxref{Tags, , Tags Tables, emacs, Emacs Manual}) will be produced that |
(@pxref{Tags, , Tags Tables, emacs, Emacs Manual}) will be produced that |
contains the definitions of all words defined afterwards. You can then |
contains the definitions of all words defined afterwards. You can then |
Line 3825 Table,emacs, Emacs Manual}). The TAGS fi
|
Line 4371 Table,emacs, Emacs Manual}). The TAGS fi
|
@file{$(datadir)/gforth/$(VERSION)/TAGS} (e.g., |
@file{$(datadir)/gforth/$(VERSION)/TAGS} (e.g., |
@file{/usr/local/share/gforth/0.2.0/TAGS}). |
@file{/usr/local/share/gforth/0.2.0/TAGS}). |
|
|
|
@cindex @file{.emacs} |
To get all these benefits, add the following lines to your @file{.emacs} |
To get all these benefits, add the following lines to your @file{.emacs} |
file: |
file: |
|
|
Line 3833 file:
|
Line 4380 file:
|
(setq auto-mode-alist (cons '("\\.fs\\'" . forth-mode) auto-mode-alist)) |
(setq auto-mode-alist (cons '("\\.fs\\'" . forth-mode) auto-mode-alist)) |
@end example |
@end example |
|
|
@node Internals, Bugs, Emacs and Gforth, Top |
@node Image Files, Engine, Emacs and Gforth, Top |
@chapter Internals |
@chapter Image Files |
|
@cindex image files |
|
@cindex @code{.fi} files |
|
@cindex precompiled Forth code |
|
@cindex dictionary in persistent form |
|
@cindex persistent form of dictionary |
|
|
|
An image file is a file containing an image of the Forth dictionary, |
|
i.e., compiled Forth code and data residing in the dictionary. By |
|
convention, we use the extension @code{.fi} for image files. |
|
|
|
@menu |
|
* Image File Background:: Why have image files? |
|
* Non-Relocatable Image Files:: don't always work. |
|
* Data-Relocatable Image Files:: are better. |
|
* Fully Relocatable Image Files:: better yet. |
|
* Stack and Dictionary Sizes:: Setting the default sizes for an image. |
|
* Running Image Files:: @code{gforth -i @var{file}} or @var{file}. |
|
* Modifying the Startup Sequence:: and turnkey applications. |
|
@end menu |
|
|
|
@node Image File Background, Non-Relocatable Image Files, Image Files, Image Files |
|
@section Image File Background |
|
@cindex image file background |
|
|
|
Our Forth system consists not only of primitives, but also of |
|
definitions written in Forth. Since the Forth compiler itself belongs to |
|
those definitions, it is not possible to start the system with the |
|
primitives and the Forth source alone. Therefore we provide the Forth |
|
code as an image file in nearly executable form. At the start of the |
|
system a C routine loads the image file into memory, optionally |
|
relocates the addresses, then sets up the memory (stacks etc.) according |
|
to information in the image file, and starts executing Forth code. |
|
|
|
The image file variants represent different compromises between the |
|
goals of making it easy to generate image files and making them |
|
portable. |
|
|
|
@cindex relocation at run-time |
|
Win32Forth 3.4 and Mitch Bradleys @code{cforth} use relocation at |
|
run-time. This avoids many of the complications discussed below (image |
|
files are data relocatable without further ado), but costs performance |
|
(one addition per memory access). |
|
|
|
@cindex relocation at load-time |
|
By contrast, our loader performs relocation at image load time. The |
|
loader also has to replace tokens standing for primitive calls with the |
|
appropriate code-field addresses (or code addresses in the case of |
|
direct threading). |
|
|
|
There are three kinds of image files, with different degrees of |
|
relocatability: non-relocatable, data-relocatable, and fully relocatable |
|
image files. |
|
|
|
@cindex image file loader |
|
@cindex relocating loader |
|
@cindex loader for image files |
|
These image file variants have several restrictions in common; they are |
|
caused by the design of the image file loader: |
|
|
|
@itemize @bullet |
|
@item |
|
There is only one segment; in particular, this means, that an image file |
|
cannot represent @code{ALLOCATE}d memory chunks (and pointers to |
|
them). And the contents of the stacks are not represented, either. |
|
|
|
@item |
|
The only kinds of relocation supported are: adding the same offset to |
|
all cells that represent data addresses; and replacing special tokens |
|
with code addresses or with pieces of machine code. |
|
|
|
If any complex computations involving addresses are performed, the |
|
results cannot be represented in the image file. Several applications that |
|
use such computations come to mind: |
|
@itemize @minus |
|
@item |
|
Hashing addresses (or data structures which contain addresses) for table |
|
lookup. If you use Gforth's @code{table}s or @code{wordlist}s for this |
|
purpose, you will have no problem, because the hash tables are |
|
recomputed automatically when the system is started. If you use your own |
|
hash tables, you will have to do something similar. |
|
|
|
@item |
|
There's a cute implementation of doubly-linked lists that uses |
|
@code{XOR}ed addresses. You could represent such lists as singly-linked |
|
in the image file, and restore the doubly-linked representation on |
|
startup.@footnote{In my opinion, though, you should think thrice before |
|
using a doubly-linked list (whatever implementation).} |
|
|
|
@item |
|
The code addresses of run-time routines like @code{docol:} cannot be |
|
represented in the image file (because their tokens would be replaced by |
|
machine code in direct threaded implementations). As a workaround, |
|
compute these addresses at run-time with @code{>code-address} from the |
|
executions tokens of appropriate words (see the definitions of |
|
@code{docol:} and friends in @file{kernel.fs}). |
|
|
|
@item |
|
On many architectures addresses are represented in machine code in some |
|
shifted or mangled form. You cannot put @code{CODE} words that contain |
|
absolute addresses in this form in a relocatable image file. Workarounds |
|
are representing the address in some relative form (e.g., relative to |
|
the CFA, which is present in some register), or loading the address from |
|
a place where it is stored in a non-mangled form. |
|
@end itemize |
|
@end itemize |
|
|
|
@node Non-Relocatable Image Files, Data-Relocatable Image Files, Image File Background, Image Files |
|
@section Non-Relocatable Image Files |
|
@cindex non-relocatable image files |
|
@cindex image files, non-relocatable |
|
|
|
These files are simple memory dumps of the dictionary. They are specific |
|
to the executable (i.e., @file{gforth} file) they were created |
|
with. What's worse, they are specific to the place on which the |
|
dictionary resided when the image was created. Now, there is no |
|
guarantee that the dictionary will reside at the same place the next |
|
time you start Gforth, so there's no guarantee that a non-relocatable |
|
image will work the next time (Gforth will complain instead of crashing, |
|
though). |
|
|
|
You can create a non-relocatable image file with |
|
|
|
doc-savesystem |
|
|
|
@node Data-Relocatable Image Files, Fully Relocatable Image Files, Non-Relocatable Image Files, Image Files |
|
@section Data-Relocatable Image Files |
|
@cindex data-relocatable image files |
|
@cindex image files, data-relocatable |
|
|
|
These files contain relocatable data addresses, but fixed code addresses |
|
(instead of tokens). They are specific to the executable (i.e., |
|
@file{gforth} file) they were created with. For direct threading on some |
|
architectures (e.g., the i386), data-relocatable images do not work. You |
|
get a data-relocatable image, if you use @file{gforth-makeimage} with a |
|
Gforth binary that is not doubly indirect threaded (@pxref{Fully |
|
Relocatable Image Files}). |
|
|
|
@node Fully Relocatable Image Files, Stack and Dictionary Sizes, Data-Relocatable Image Files, Image Files |
|
@section Fully Relocatable Image Files |
|
@cindex fully relocatable image files |
|
@cindex image files, fully relocatable |
|
|
|
@cindex @file{kern*.fi}, relocatability |
|
@cindex @file{gforth.fi}, relocatability |
|
These image files have relocatable data addresses, and tokens for code |
|
addresses. They can be used with different binaries (e.g., with and |
|
without debugging) on the same machine, and even across machines with |
|
the same data formats (byte order, cell size, floating point |
|
format). However, they are usually specific to the version of Gforth |
|
they were created with. The files @file{gforth.fi} and @file{kernl*.fi} |
|
are fully relocatable. |
|
|
|
There are two ways to create a fully relocatable image file: |
|
|
|
@menu |
|
* gforth-makeimage:: The normal way |
|
* cross.fs:: The hard way |
|
@end menu |
|
|
|
@node gforth-makeimage, cross.fs, Fully Relocatable Image Files, Fully Relocatable Image Files |
|
@subsection @file{gforth-makeimage} |
|
@cindex @file{comp-image.fs} |
|
@cindex @file{gforth-makeimage} |
|
|
|
You will usually use @file{gforth-makeimage}. If you want to create an |
|
image @var{file} that contains everything you would load by invoking |
|
Gforth with @code{gforth @var{options}}, you simply say |
|
@example |
|
gforth-makeimage @var{file} @var{options} |
|
@end example |
|
|
|
E.g., if you want to create an image @file{asm.fi} that has the file |
|
@file{asm.fs} loaded in addition to the usual stuff, you could do it |
|
like this: |
|
|
|
@example |
|
gforth-makeimage asm.fi asm.fs |
|
@end example |
|
|
|
@file{gforth-makeimage} works like this: It produces two non-relocatable |
|
images for different addresses and then compares them. Its output |
|
reflects this: first you see the output (if any) of the two Gforth |
|
invocations that produce the nonrelocatable image files, then you see |
|
the output of the comparing program: It displays the offset used for |
|
data addresses and the offset used for code addresses; |
|
moreover, for each cell that cannot be represented correctly in the |
|
image files, it displays a line like the following one: |
|
|
|
@example |
|
78DC BFFFFA50 BFFFFA40 |
|
@end example |
|
|
|
This means that at offset $78dc from @code{forthstart}, one input image |
|
contains $bffffa50, and the other contains $bffffa40. Since these cells |
|
cannot be represented correctly in the output image, you should examine |
|
these places in the dictionary and verify that these cells are dead |
|
(i.e., not read before they are written). |
|
|
|
\cindex @code{savesystem} during @file{gforth-makeimage} |
|
\cindex @code{bye} during @file{gforth-makeimage} |
|
\cindex doubly indirect threaded code |
|
\cindex environment variable @code{GFORTHD} |
|
\cindex @code{GFORTHD} environment variable |
|
\cindex @code{gforth-ditc} |
|
There are a few wrinkles: After processing the passed @var{options}, the |
|
words @code{savesystem} and @code{bye} must be visible. A special doubly |
|
indirect threaded version of the @file{gforth} executable is used for |
|
creating the nonrelocatable images; you can pass the exact filename of |
|
this executable through the environment variable @code{GFORTHD} |
|
(default: @file{gforth-ditc}); if you pass a version that is not doubly |
|
indirect threaded, you will not get a fully relocatable image, but a |
|
data-relocatable image (because there is no code address offset). |
|
|
|
@node cross.fs, , gforth-makeimage, Fully Relocatable Image Files |
|
@subsection @file{cross.fs} |
|
@cindex @file{cross.fs} |
|
@cindex cross-compiler |
|
@cindex metacompiler |
|
|
|
You can also use @code{cross}, a batch compiler that accepts a Forth-like |
|
programming language. This @code{cross} language has to be documented |
|
yet. |
|
|
|
@cindex target compiler |
|
@code{cross} also allows you to create image files for machines with |
|
different data sizes and data formats than the one used for generating |
|
the image file. You can also use it to create an application image that |
|
does not contain a Forth compiler. These features are bought with |
|
restrictions and inconveniences in programming. E.g., addresses have to |
|
be stored in memory with special words (@code{A!}, @code{A,}, etc.) in |
|
order to make the code relocatable. |
|
|
|
|
|
@node Stack and Dictionary Sizes, Running Image Files, Fully Relocatable Image Files, Image Files |
|
@section Stack and Dictionary Sizes |
|
@cindex image file, stack and dictionary sizes |
|
@cindex dictionary size default |
|
@cindex stack size default |
|
|
|
If you invoke Gforth with a command line flag for the size |
|
(@pxref{Invoking Gforth}), the size you specify is stored in the |
|
dictionary. If you save the dictionary with @code{savesystem} or create |
|
an image with @file{gforth-makeimage}, this size will become the default |
|
for the resulting image file. E.g., the following will create a |
|
fully relocatable version of gforth.fi with a 1MB dictionary: |
|
|
|
@example |
|
gforth-makeimage gforth.fi -m 1M |
|
@end example |
|
|
|
In other words, if you want to set the default size for the dictionary |
|
and the stacks of an image, just invoke @file{gforth-makeimage} with the |
|
appropriate options when creating the image. |
|
|
|
@cindex stack size, cache-friendly |
|
Note: For cache-friendly behaviour (i.e., good performance), you should |
|
make the sizes of the stacks modulo, say, 2K, somewhat different. E.g., |
|
the default stack sizes are: data: 16k (mod 2k=0); fp: 15.5k (mod |
|
2k=1.5k); return: 15k(mod 2k=1k); locals: 14.5k (mod 2k=0.5k). |
|
|
|
@node Running Image Files, Modifying the Startup Sequence, Stack and Dictionary Sizes, Image Files |
|
@section Running Image Files |
|
@cindex running image files |
|
@cindex invoking image files |
|
@cindex image file invocation |
|
|
|
@cindex -i, invoke image file |
|
@cindex --image file, invoke image file |
|
You can invoke Gforth with an image file @var{image} instead of the |
|
default @file{gforth.fi} with the @code{-i} flag (@pxref{Invoking Gforth}): |
|
@example |
|
gforth -i @var{image} |
|
@end example |
|
|
|
@cindex executable image file |
|
@cindex image files, executable |
|
If your operating system supports starting scripts with a line of the |
|
form @code{#! ...}, you can make your image file executable, and you'll |
|
just have to type the image file name to start Gforth with this image |
|
file (note that the file extension @code{.fi} is just a convention). |
|
|
|
I.e., in most Unix systems, you just have to make the image file |
|
@var{image} executable with |
|
|
|
@example |
|
chmod +x @var{image} |
|
@end example |
|
|
|
and then you can invoke it by simply typing @var{image} instead of |
|
@code{gforth -i @var{image}}. |
|
|
|
@node Modifying the Startup Sequence, , Running Image Files, Image Files |
|
@section Modifying the Startup Sequence |
|
@cindex startup sequence for image file |
|
@cindex image file initialization sequence |
|
@cindex initialization sequence of image file |
|
|
|
You can add your own initialization to the startup sequence through the |
|
deferred word |
|
|
|
doc-'cold |
|
|
|
@code{'cold} is invoked just before the image-specific command line |
|
processing (by default, loading files and evaluating (@code{-e}) strings) |
|
starts. |
|
|
|
A sequence for adding your initialization usually looks like this: |
|
|
|
@example |
|
:noname |
|
Defers 'cold \ do other initialization stuff (e.g., rehashing wordlists) |
|
... \ your stuff |
|
; IS 'cold |
|
@end example |
|
|
|
@cindex turnkey image files |
|
@cindex image files, turnkey applications |
|
You can make a turnkey image by letting @code{'cold} execute a word |
|
(your turnkey application) that never returns; instead, it exits Gforth |
|
via @code{bye} or @code{throw}. |
|
|
|
@c ****************************************************************** |
|
@node Engine, Bugs, Image Files, Top |
|
@chapter Engine |
|
@cindex engine |
|
@cindex virtual machine |
|
|
Reading this section is not necessary for programming with Gforth. It |
Reading this section is not necessary for programming with Gforth. It |
should be helpful for finding your way in the Gforth sources. |
may be helpful for finding your way in the Gforth sources. |
|
|
The ideas in this section have also been published in the papers |
The ideas in this section have also been published in the papers |
@cite{ANS fig/GNU/??? Forth} (in German) by Bernd Paysan, presented at |
@cite{ANS fig/GNU/??? Forth} (in German) by Bernd Paysan, presented at |
Line 3849 Ertl, presented at EuroForth '93; the la
|
Line 4722 Ertl, presented at EuroForth '93; the la
|
* Portability:: |
* Portability:: |
* Threading:: |
* Threading:: |
* Primitives:: |
* Primitives:: |
* System Architecture:: |
|
* Performance:: |
* Performance:: |
@end menu |
@end menu |
|
|
@node Portability, Threading, Internals, Internals |
@node Portability, Threading, Engine, Engine |
@section Portability |
@section Portability |
|
@cindex engine portability |
|
|
One of the main goals of the effort is availability across a wide range |
One of the main goals of the effort is availability across a wide range |
of personal machines. fig-Forth, and, to a lesser extent, F83, achieved |
of personal machines. fig-Forth, and, to a lesser extent, F83, achieved |
Line 3862 this goal by manually coding the engine
|
Line 4735 this goal by manually coding the engine
|
then-popular processors. This approach is very labor-intensive and the |
then-popular processors. This approach is very labor-intensive and the |
results are short-lived due to progress in computer architecture. |
results are short-lived due to progress in computer architecture. |
|
|
|
@cindex C, using C for the engine |
Others have avoided this problem by coding in C, e.g., Mitch Bradley |
Others have avoided this problem by coding in C, e.g., Mitch Bradley |
(cforth), Mikael Patel (TILE) and Dirk Zoller (pfe). This approach is |
(cforth), Mikael Patel (TILE) and Dirk Zoller (pfe). This approach is |
particularly popular for UNIX-based Forths due to the large variety of |
particularly popular for UNIX-based Forths due to the large variety of |
Line 3869 architectures of UNIX machines. Unfortun
|
Line 4743 architectures of UNIX machines. Unfortun
|
does not mix well with the goals of efficiency and with using |
does not mix well with the goals of efficiency and with using |
traditional techniques: Indirect or direct threading cannot be expressed |
traditional techniques: Indirect or direct threading cannot be expressed |
in C, and switch threading, the fastest technique available in C, is |
in C, and switch threading, the fastest technique available in C, is |
significantly slower. Another problem with C is that it's very |
significantly slower. Another problem with C is that it is very |
cumbersome to express double integer arithmetic. |
cumbersome to express double integer arithmetic. |
|
|
|
@cindex GNU C for the engine |
|
@cindex long long |
Fortunately, there is a portable language that does not have these |
Fortunately, there is a portable language that does not have these |
limitations: GNU C, the version of C processed by the GNU C compiler |
limitations: GNU C, the version of C processed by the GNU C compiler |
(@pxref{C Extensions, , Extensions to the C Language Family, gcc.info, |
(@pxref{C Extensions, , Extensions to the C Language Family, gcc.info, |
Line 3893 on all these machines.
|
Line 4769 on all these machines.
|
Writing in a portable language has the reputation of producing code that |
Writing in a portable language has the reputation of producing code that |
is slower than assembly. For our Forth engine we repeatedly looked at |
is slower than assembly. For our Forth engine we repeatedly looked at |
the code produced by the compiler and eliminated most compiler-induced |
the code produced by the compiler and eliminated most compiler-induced |
inefficiencies by appropriate changes in the source-code. |
inefficiencies by appropriate changes in the source code. |
|
|
|
@cindex explicit register declarations |
|
@cindex --enable-force-reg, configuration flag |
|
@cindex -DFORCE_REG |
However, register allocation cannot be portably influenced by the |
However, register allocation cannot be portably influenced by the |
programmer, leading to some inefficiencies on register-starved |
programmer, leading to some inefficiencies on register-starved |
machines. We use explicit register declarations (@pxref{Explicit Reg |
machines. We use explicit register declarations (@pxref{Explicit Reg |
Vars, , Variables in Specified Registers, gcc.info, GNU C Manual}) to |
Vars, , Variables in Specified Registers, gcc.info, GNU C Manual}) to |
improve the speed on some machines. They are turned on by using the |
improve the speed on some machines. They are turned on by using the |
@code{gcc} switch @code{-DFORCE_REG}. Unfortunately, this feature not |
configuration flag @code{--enable-force-reg} (@code{gcc} switch |
only depends on the machine, but also on the compiler version: On some |
@code{-DFORCE_REG}). Unfortunately, this feature not only depends on the |
machines some compiler versions produce incorrect code when certain |
machine, but also on the compiler version: On some machines some |
explicit register declarations are used. So by default |
compiler versions produce incorrect code when certain explicit register |
@code{-DFORCE_REG} is not used. |
declarations are used. So by default @code{-DFORCE_REG} is not used. |
|
|
@node Threading, Primitives, Portability, Internals |
@node Threading, Primitives, Portability, Engine |
@section Threading |
@section Threading |
|
@cindex inner interpreter implementation |
|
@cindex threaded code implementation |
|
|
|
@cindex labels as values |
GNU C's labels as values extension (available since @code{gcc-2.0}, |
GNU C's labels as values extension (available since @code{gcc-2.0}, |
@pxref{Labels as Values, , Labels as Values, gcc.info, GNU C Manual}) |
@pxref{Labels as Values, , Labels as Values, gcc.info, GNU C Manual}) |
makes it possible to take the address of @var{label} by writing |
makes it possible to take the address of @var{label} by writing |
Line 3916 makes it possible to take the address of
|
Line 4798 makes it possible to take the address of
|
@code{goto *@var{address}}. I.e., @code{goto *&&x} is the same as |
@code{goto *@var{address}}. I.e., @code{goto *&&x} is the same as |
@code{goto x}. |
@code{goto x}. |
|
|
|
@cindex NEXT, indirect threaded |
|
@cindex indirect threaded inner interpreter |
|
@cindex inner interpreter, indirect threaded |
With this feature an indirect threaded NEXT looks like: |
With this feature an indirect threaded NEXT looks like: |
@example |
@example |
cfa = *ip++; |
cfa = *ip++; |
ca = *cfa; |
ca = *cfa; |
goto *ca; |
goto *ca; |
@end example |
@end example |
|
@cindex instruction pointer |
For those unfamiliar with the names: @code{ip} is the Forth instruction |
For those unfamiliar with the names: @code{ip} is the Forth instruction |
pointer; the @code{cfa} (code-field address) corresponds to ANS Forths |
pointer; the @code{cfa} (code-field address) corresponds to ANS Forths |
execution token and points to the code field of the next word to be |
execution token and points to the code field of the next word to be |
Line 3929 executed; The @code{ca} (code address) f
|
Line 4815 executed; The @code{ca} (code address) f
|
executable code, e.g., a primitive or the colon definition handler |
executable code, e.g., a primitive or the colon definition handler |
@code{docol}. |
@code{docol}. |
|
|
|
@cindex NEXT, direct threaded |
|
@cindex direct threaded inner interpreter |
|
@cindex inner interpreter, direct threaded |
Direct threading is even simpler: |
Direct threading is even simpler: |
@example |
@example |
ca = *ip++; |
ca = *ip++; |
Line 3946 Of course we have packaged the whole thi
|
Line 4835 Of course we have packaged the whole thi
|
|
|
@node Scheduling, Direct or Indirect Threaded?, Threading, Threading |
@node Scheduling, Direct or Indirect Threaded?, Threading, Threading |
@subsection Scheduling |
@subsection Scheduling |
|
@cindex inner interpreter optimization |
|
|
There is a little complication: Pipelined and superscalar processors, |
There is a little complication: Pipelined and superscalar processors, |
i.e., RISC and some modern CISC machines can process independent |
i.e., RISC and some modern CISC machines can process independent |
Line 3985 switch is on by default on machines that
|
Line 4875 switch is on by default on machines that
|
|
|
@node Direct or Indirect Threaded?, DOES>, Scheduling, Threading |
@node Direct or Indirect Threaded?, DOES>, Scheduling, Threading |
@subsection Direct or Indirect Threaded? |
@subsection Direct or Indirect Threaded? |
|
@cindex threading, direct or indirect? |
|
|
|
@cindex -DDIRECT_THREADED |
Both! After packaging the nasty details in macro definitions we |
Both! After packaging the nasty details in macro definitions we |
realized that we could switch between direct and indirect threading by |
realized that we could switch between direct and indirect threading by |
simply setting a compilation flag (@code{-DDIRECT_THREADED}) and |
simply setting a compilation flag (@code{-DDIRECT_THREADED}) and |
Line 3993 defining a few machine-specific macros f
|
Line 4885 defining a few machine-specific macros f
|
On the Forth level we also offer access words that hide the |
On the Forth level we also offer access words that hide the |
differences between the threading methods (@pxref{Threading Words}). |
differences between the threading methods (@pxref{Threading Words}). |
|
|
Indirect threading is implemented completely |
Indirect threading is implemented completely machine-independently. |
machine-independently. Direct threading needs routines for creating |
Direct threading needs routines for creating jumps to the executable |
jumps to the executable code (e.g. to docol or dodoes). These routines |
code (e.g. to docol or dodoes). These routines are inherently |
are inherently machine-dependent, but they do not amount to many source |
machine-dependent, but they do not amount to many source lines. I.e., |
lines. I.e., even porting direct threading to a new machine is a small |
even porting direct threading to a new machine is a small effort. |
effort. |
|
|
@cindex --enable-indirect-threaded, configuration flag |
|
@cindex --enable-direct-threaded, configuration flag |
|
The default threading method is machine-dependent. You can enforce a |
|
specific threading method when building Gforth with the configuration |
|
flag @code{--enable-direct-threaded} or |
|
@code{--enable-indirect-threaded}. Note that direct threading is not |
|
supported on all machines. |
|
|
@node DOES>, , Direct or Indirect Threaded?, Threading |
@node DOES>, , Direct or Indirect Threaded?, Threading |
@subsection DOES> |
@subsection DOES> |
|
@cindex @code{DOES>} implementation |
|
|
|
@cindex dodoes routine |
|
@cindex DOES-code |
One of the most complex parts of a Forth engine is @code{dodoes}, i.e., |
One of the most complex parts of a Forth engine is @code{dodoes}, i.e., |
the chunk of code executed by every word defined by a |
the chunk of code executed by every word defined by a |
@code{CREATE}...@code{DOES>} pair. The main problem here is: How to find |
@code{CREATE}...@code{DOES>} pair. The main problem here is: How to find |
the Forth code to be executed, i.e. the code after the @code{DOES>} (the |
the Forth code to be executed, i.e. the code after the |
DOES-code)? There are two solutions: |
@code{DOES>} (the DOES-code)? There are two solutions: |
|
|
In fig-Forth the code field points directly to the dodoes and the |
In fig-Forth the code field points directly to the dodoes and the |
DOES-code address is stored in the cell after the code address |
DOES-code address is stored in the cell after the code address (i.e. at |
(i.e. at cfa cell+). It may seem that this solution is illegal in the |
@code{@var{cfa} cell+}). It may seem that this solution is illegal in |
Forth-79 and all later standards, because in fig-Forth this address |
the Forth-79 and all later standards, because in fig-Forth this address |
lies in the body (which is illegal in these standards). However, by |
lies in the body (which is illegal in these standards). However, by |
making the code field larger for all words this solution becomes legal |
making the code field larger for all words this solution becomes legal |
again. We use this approach for the indirect threaded version. Leaving |
again. We use this approach for the indirect threaded version and for |
a cell unused in most words is a bit wasteful, but on the machines we |
direct threading on some machines. Leaving a cell unused in most words |
are targeting this is hardly a problem. The other reason for having a |
is a bit wasteful, but on the machines we are targeting this is hardly a |
code field size of two cells is to avoid having different image files |
problem. The other reason for having a code field size of two cells is |
for direct and indirect threaded systems (@pxref{System Architecture}). |
to avoid having different image files for direct and indirect threaded |
|
systems (direct threaded systems require two-cell code fields on many |
|
machines). |
|
|
|
@cindex DOES-handler |
The other approach is that the code field points or jumps to the cell |
The other approach is that the code field points or jumps to the cell |
after @code{DOES}. In this variant there is a jump to @code{dodoes} at |
after @code{DOES}. In this variant there is a jump to @code{dodoes} at |
this address. @code{dodoes} can then get the DOES-code address by |
this address (the DOES-handler). @code{dodoes} can then get the |
computing the code address, i.e., the address of the jump to dodoes, |
DOES-code address by computing the code address, i.e., the address of |
and add the length of that jump field. A variant of this is to have a |
the jump to dodoes, and add the length of that jump field. A variant of |
call to @code{dodoes} after the @code{DOES>}; then the return address |
this is to have a call to @code{dodoes} after the @code{DOES>}; then the |
(which can be found in the return register on RISCs) is the DOES-code |
return address (which can be found in the return register on RISCs) is |
address. Since the two cells available in the code field are usually |
the DOES-code address. Since the two cells available in the code field |
used up by the jump to the code address in direct threading, we use |
are used up by the jump to the code address in direct threading on many |
this approach for direct threading. We did not want to add another |
architectures, we use this approach for direct threading on these |
cell to the code field. |
architectures. We did not want to add another cell to the code field. |
|
|
@node Primitives, System Architecture, Threading, Internals |
@node Primitives, Performance, Threading, Engine |
@section Primitives |
@section Primitives |
|
@cindex primitives, implementation |
|
@cindex virtual machine instructions, implementation |
|
|
@menu |
@menu |
* Automatic Generation:: |
* Automatic Generation:: |
Line 4043 cell to the code field.
|
Line 4951 cell to the code field.
|
|
|
@node Automatic Generation, TOS Optimization, Primitives, Primitives |
@node Automatic Generation, TOS Optimization, Primitives, Primitives |
@subsection Automatic Generation |
@subsection Automatic Generation |
|
@cindex primitives, automatic generation |
|
|
|
@cindex @file{prims2x.fs} |
Since the primitives are implemented in a portable language, there is no |
Since the primitives are implemented in a portable language, there is no |
longer any need to minimize the number of primitives. On the contrary, |
longer any need to minimize the number of primitives. On the contrary, |
having many primitives is an advantage: speed. In order to reduce the |
having many primitives has an advantage: speed. In order to reduce the |
number of errors in primitives and to make programming them easier, we |
number of errors in primitives and to make programming them easier, we |
provide a tool, the primitive generator (@file{prims2x.fs}), that |
provide a tool, the primitive generator (@file{prims2x.fs}), that |
automatically generates most (and sometimes all) of the C code for a |
automatically generates most (and sometimes all) of the C code for a |
primitive from the stack effect notation. The source for a primitive |
primitive from the stack effect notation. The source for a primitive |
has the following form: |
has the following form: |
|
|
|
@cindex primitive source format |
@format |
@format |
@var{Forth-name} @var{stack-effect} @var{category} [@var{pronounc.}] |
@var{Forth-name} @var{stack-effect} @var{category} [@var{pronounc.}] |
[@code{""}@var{glossary entry}@code{""}] |
[@code{""}@var{glossary entry}@code{""}] |
Line 4122 fall through to NEXT.
|
Line 5033 fall through to NEXT.
|
|
|
@node TOS Optimization, Produced code, Automatic Generation, Primitives |
@node TOS Optimization, Produced code, Automatic Generation, Primitives |
@subsection TOS Optimization |
@subsection TOS Optimization |
|
@cindex TOS optimization for primitives |
|
@cindex primitives, keeping the TOS in a register |
|
|
An important optimization for stack machine emulators, e.g., Forth |
An important optimization for stack machine emulators, e.g., Forth |
engines, is keeping one or more of the top stack items in |
engines, is keeping one or more of the top stack items in |
Line 4135 due to fewer loads from and stores to th
|
Line 5048 due to fewer loads from and stores to th
|
@var{y<n}, due to additional moves between registers. |
@var{y<n}, due to additional moves between registers. |
@end itemize |
@end itemize |
|
|
|
@cindex -DUSE_TOS |
|
@cindex -DUSE_NO_TOS |
In particular, keeping one item in a register is never a disadvantage, |
In particular, keeping one item in a register is never a disadvantage, |
if there are enough registers. Keeping two items in registers is a |
if there are enough registers. Keeping two items in registers is a |
disadvantage for frequent words like @code{?branch}, constants, |
disadvantage for frequent words like @code{?branch}, constants, |
Line 4147 otherwise it is a macro that expands int
|
Line 5062 otherwise it is a macro that expands int
|
GNU C compiler tries to keep simple variables like @code{TOS} in |
GNU C compiler tries to keep simple variables like @code{TOS} in |
registers, and it usually succeeds, if there are enough registers. |
registers, and it usually succeeds, if there are enough registers. |
|
|
|
@cindex -DUSE_FTOS |
|
@cindex -DUSE_NO_FTOS |
The primitive generator performs the TOS optimization for the |
The primitive generator performs the TOS optimization for the |
floating-point stack, too (@code{-DUSE_FTOS}). For floating-point |
floating-point stack, too (@code{-DUSE_FTOS}). For floating-point |
operations the benefit of this optimization is even larger: |
operations the benefit of this optimization is even larger: |
Line 4174 effect @code{--} no stores or loads shou
|
Line 5091 effect @code{--} no stores or loads shou
|
|
|
@node Produced code, , TOS Optimization, Primitives |
@node Produced code, , TOS Optimization, Primitives |
@subsection Produced code |
@subsection Produced code |
|
@cindex primitives, assembly code listing |
|
|
|
@cindex @file{engine.s} |
To see what assembly code is produced for the primitives on your machine |
To see what assembly code is produced for the primitives on your machine |
with your compiler and your flag settings, type @code{make engine.s} and |
with your compiler and your flag settings, type @code{make engine.s} and |
look at the resulting file @file{engine.s}. |
look at the resulting file @file{engine.s}. |
|
|
@node System Architecture, Performance, Primitives, Internals |
@node Performance, , Primitives, Engine |
@section System Architecture |
|
|
|
Our Forth system consists not only of primitives, but also of |
|
definitions written in Forth. Since the Forth compiler itself belongs |
|
to those definitions, it is not possible to start the system with the |
|
primitives and the Forth source alone. Therefore we provide the Forth |
|
code as an image file in nearly executable form. At the start of the |
|
system a C routine loads the image file into memory, sets up the |
|
memory (stacks etc.) according to information in the image file, and |
|
starts executing Forth code. |
|
|
|
The image file format is a compromise between the goals of making it |
|
easy to generate image files and making them portable. The easiest way |
|
to generate an image file is to just generate a memory dump. However, |
|
this kind of image file cannot be used on a different machine, or on |
|
the next version of the engine on the same machine, it even might not |
|
work with the same engine compiled by a different version of the C |
|
compiler. We would like to have as few versions of the image file as |
|
possible, because we do not want to distribute many versions of the |
|
same image file, and to make it easy for the users to use their image |
|
files on many machines. We currently need to create a different image |
|
file for machines with different cell sizes and different byte order |
|
(little- or big-endian)@footnote{We are considering adding information to the |
|
image file that enables the loader to change the byte order.}. |
|
|
|
Forth code that is going to end up in a portable image file has to |
|
comply to some restrictions: addresses have to be stored in memory with |
|
special words (@code{A!}, @code{A,}, etc.) in order to make the code |
|
relocatable. Cells, floats, etc., have to be stored at the natural |
|
alignment boundaries@footnote{E.g., store floats (8 bytes) at an address |
|
divisible by~8. This happens automatically in our system when you use |
|
the ANS Forth alignment words.}, in order to avoid alignment faults on |
|
machines with stricter alignment. The image file is produced by a |
|
metacompiler (@file{cross.fs}). |
|
|
|
So, unlike the image file of Mitch Bradleys @code{cforth}, our image |
|
file is not directly executable, but has to undergo some manipulations |
|
during loading. Address relocation is performed at image load-time, not |
|
at run-time. The loader also has to replace tokens standing for |
|
primitive calls with the appropriate code-field addresses (or code |
|
addresses in the case of direct threading). |
|
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@node Performance, , System Architecture, Internals |
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@section Performance |
@section Performance |
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@cindex performance of some Forth interpreters |
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@cindex engine performance |
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@cindex benchmarking Forth systems |
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@cindex Gforth performance |
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On RISCs the Gforth engine is very close to optimal; i.e., it is usually |
On RISCs the Gforth engine is very close to optimal; i.e., it is usually |
impossible to write a significantly faster engine. |
impossible to write a significantly faster engine. |
Line 4236 and hand-tuned it for the 486; this syst
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Line 5116 and hand-tuned it for the 486; this syst
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Sieve benchmark on a 486DX2/66 than Gforth compiled with |
Sieve benchmark on a 486DX2/66 than Gforth compiled with |
@code{gcc-2.6.3} with @code{-DFORCE_REG}. |
@code{gcc-2.6.3} with @code{-DFORCE_REG}. |
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@cindex Win32Forth performance |
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@cindex NT Forth performance |
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@cindex eforth performance |
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@cindex ThisForth performance |
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@cindex PFE performance |
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@cindex TILE performance |
However, this potential advantage of assembly language implementations |
However, this potential advantage of assembly language implementations |
is not necessarily realized in complete Forth systems: We compared |
is not necessarily realized in complete Forth systems: We compared |
Gforth (direct threaded, compiled with @code{gcc-2.6.3} and |
Gforth (direct threaded, compiled with @code{gcc-2.6.3} and |
Line 4280 not written optimally for the 486 (e.g.,
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Line 5166 not written optimally for the 486 (e.g.,
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instruction). In addition, Win32Forth uses a comfortable, but costly |
instruction). In addition, Win32Forth uses a comfortable, but costly |
method for relocating the Forth image: like @code{cforth}, it computes |
method for relocating the Forth image: like @code{cforth}, it computes |
the actual addresses at run time, resulting in two address computations |
the actual addresses at run time, resulting in two address computations |
per NEXT (@pxref{System Architecture}). |
per NEXT (@pxref{Image File Background}). |
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Only Eforth with the peephole optimizer performs comparable to |
Only Eforth with the peephole optimizer performs comparable to |
Gforth. The speedups achieved with peephole optimization of threaded |
Gforth. The speedups achieved with peephole optimization of threaded |
Line 4288 code are quite remarkable. Adding a peep
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Line 5174 code are quite remarkable. Adding a peep
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cause similar speedups. |
cause similar speedups. |
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The speedup of Gforth over PFE, ThisForth and TILE can be easily |
The speedup of Gforth over PFE, ThisForth and TILE can be easily |
explained with the self-imposed restriction to standard C, which makes |
explained with the self-imposed restriction of the latter systems to |
efficient threading impossible (however, the measured implementation of |
standard C, which makes efficient threading impossible (however, the |
PFE uses a GNU C extension: @ref{Global Reg Vars, , Defining Global |
measured implementation of PFE uses a GNU C extension: @ref{Global Reg |
Register Variables, gcc.info, GNU C Manual}). Moreover, current C |
Vars, , Defining Global Register Variables, gcc.info, GNU C Manual}). |
compilers have a hard time optimizing other aspects of the ThisForth |
Moreover, current C compilers have a hard time optimizing other aspects |
and the TILE source. |
of the ThisForth and the TILE source. |
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Note that the performance of Gforth on 386 architecture processors |
Note that the performance of Gforth on 386 architecture processors |
varies widely with the version of @code{gcc} used. E.g., @code{gcc-2.5.8} |
varies widely with the version of @code{gcc} used. E.g., @code{gcc-2.5.8} |
Line 4302 machine registers by itself and would no
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Line 5188 machine registers by itself and would no
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register declarations, giving a 1.3 times slower engine (on a 486DX2/66 |
register declarations, giving a 1.3 times slower engine (on a 486DX2/66 |
running the Sieve) than the one measured above. |
running the Sieve) than the one measured above. |
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Note also that there have been several releases of Win32Forth since the |
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release presented here, so the results presented here may have little |
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predictive value for the performance of Win32Forth today. |
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@cindex @file{Benchres} |
In @cite{Translating Forth to Efficient C} by M. Anton Ertl and Martin |
In @cite{Translating Forth to Efficient C} by M. Anton Ertl and Martin |
Maierhofer (presented at EuroForth '95), an indirect threaded version of |
Maierhofer (presented at EuroForth '95), an indirect threaded version of |
Gforth is compared with Win32Forth, NT Forth, PFE, and ThisForth; that |
Gforth is compared with Win32Forth, NT Forth, PFE, and ThisForth; that |
version of Gforth is 2\%@minus{}8\% slower on a 486 than the version |
version of Gforth is 2%@minus{}8% slower on a 486 than the direct |
used here. The paper available at |
threaded version used here. The paper available at |
@*@file{http://www.complang.tuwien.ac.at/papers/ertl&maierhofer95.ps.gz}; |
@*@file{http://www.complang.tuwien.ac.at/papers/ertl&maierhofer95.ps.gz}; |
it also contains numbers for some native code systems. You can find |
it also contains numbers for some native code systems. You can find a |
numbers for Gforth on various machines in @file{Benchres}. |
newer version of these measurements at |
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@file{http://www.complang.tuwien.ac.at/forth/performance.html}. You can |
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find numbers for Gforth on various machines in @file{Benchres}. |
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@node Bugs, Origin, Internals, Top |
@node Bugs, Origin, Engine, Top |
@chapter Bugs |
@chapter Bugs |
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@cindex bug reporting |
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Known bugs are described in the file BUGS in the Gforth distribution. |
Known bugs are described in the file BUGS in the Gforth distribution. |
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Line 4321 If you find a bug, please send a bug rep
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Line 5215 If you find a bug, please send a bug rep
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describe the Gforth version used (it is announced at the start of an |
describe the Gforth version used (it is announced at the start of an |
interactive Gforth session), the machine and operating system (on Unix |
interactive Gforth session), the machine and operating system (on Unix |
systems you can use @code{uname -a} to produce this information), the |
systems you can use @code{uname -a} to produce this information), the |
installation options (send the @code{config.status} file), and a |
installation options (send the @file{config.status} file), and a |
complete list of changes you (or your installer) have made to the Gforth |
complete list of changes you (or your installer) have made to the Gforth |
sources (if any); it should contain a program (or a sequence of keyboard |
sources (if any); it should contain a program (or a sequence of keyboard |
commands) that reproduces the bug and a description of what you think |
commands) that reproduces the bug and a description of what you think |
Line 4335 to Report Bugs, gcc.info, GNU C Manual}.
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Line 5229 to Report Bugs, gcc.info, GNU C Manual}.
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@chapter Authors and Ancestors of Gforth |
@chapter Authors and Ancestors of Gforth |
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@section Authors and Contributors |
@section Authors and Contributors |
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@cindex authors of Gforth |
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@cindex contributors to Gforth |
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The Gforth project was started in mid-1992 by Bernd Paysan and Anton |
The Gforth project was started in mid-1992 by Bernd Paysan and Anton |
Ertl. The third major author was Jens Wilke. Lennart Benschop (who was |
Ertl. The third major author was Jens Wilke. Lennart Benschop (who was |
Line 4351 was developed across the Internet, and i
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Line 5247 was developed across the Internet, and i
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physically yet. |
physically yet. |
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@section Pedigree |
@section Pedigree |
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@cindex Pedigree of Gforth |
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Gforth descends from BigForth (1993) and fig-Forth. Gforth and PFE (by |
Gforth descends from BigForth (1993) and fig-Forth. Gforth and PFE (by |
Dirk Zoller) will cross-fertilize each other. Of course, a significant |
Dirk Zoller) will cross-fertilize each other. Of course, a significant |
Line 4386 H. Moore, presented at the HOPL-II confe
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Line 5283 H. Moore, presented at the HOPL-II confe
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Notices 28(3), 1993. You can find more historical and genealogical |
Notices 28(3), 1993. You can find more historical and genealogical |
information about Forth there. |
information about Forth there. |
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@node Word Index, Node Index, Origin, Top |
@node Word Index, Concept Index, Origin, Top |
@chapter Word Index |
@unnumbered Word Index |
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This index is as incomplete as the manual. Each word is listed with |
This index is as incomplete as the manual. Each word is listed with |
stack effect and wordset. |
stack effect and wordset. |
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@printindex fn |
@printindex fn |
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@node Node Index, , Word Index, Top |
@node Concept Index, , Word Index, Top |
@chapter Node Index |
@unnumbered Concept and Word Index |
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This index is as incomplete as the manual. Not all entries listed are |
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present verbatim in the text. Only the names are listed for the words |
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here. |
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This index is even less complete than the manual. |
@printindex cp |
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@contents |
@contents |
@bye |
@bye |