version 1.22, 1995/11/13 18:37:10
|
version 1.32, 1996/02/19 18:57:26
|
Line 7
|
Line 7
|
@comment %**end of header (This is for running Texinfo on a region.) |
@comment %**end of header (This is for running Texinfo on a region.) |
|
|
@ifinfo |
@ifinfo |
This file documents Gforth 0.1 |
This file documents Gforth 0.2 |
|
|
Copyright @copyright{} 1995 Free Software Foundation, Inc. |
Copyright @copyright{} 1995,1996 Free Software Foundation, Inc. |
|
|
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 36 Copyright @copyright{} 1995 Free Softwar
|
Line 36 Copyright @copyright{} 1995 Free Softwar
|
of in the original English. |
of in the original English. |
@end ifinfo |
@end ifinfo |
|
|
|
@finalout |
@titlepage |
@titlepage |
@sp 10 |
@sp 10 |
@center @titlefont{Gforth Manual} |
@center @titlefont{Gforth Manual} |
@sp 2 |
@sp 2 |
@center for version 0.1 |
@center for version 0.2 |
@sp 2 |
@sp 2 |
@center Anton Ertl |
@center Anton Ertl |
|
@center Bernd Paysan |
@sp 3 |
@sp 3 |
@center This manual is under construction |
@center This manual is under construction |
|
|
@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 Free Software Foundation, Inc. |
Copyright @copyright{} 1995,1996 Free Software Foundation, Inc. |
|
|
@comment !! Published by ... or You can get a copy of this manual ... |
@comment !! Published by ... or You can get a copy of this manual ... |
|
|
Line 75 Copyright @copyright{} 1995 Free Softwar
|
Line 77 Copyright @copyright{} 1995 Free Softwar
|
@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 0.1. |
personal machines. This manual corresponds to version 0.2. |
@end ifinfo |
@end ifinfo |
|
|
@menu |
@menu |
Line 89 personal machines. This manual correspon
|
Line 91 personal machines. This manual correspon
|
* Emacs and Gforth:: The Gforth Mode |
* Emacs and Gforth:: The Gforth Mode |
* Internals:: Implementation details |
* Internals:: Implementation details |
* Bugs:: How to report them |
* Bugs:: How to report them |
* Pedigree:: 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 |
* Node Index:: An item for each node |
@end menu |
@end menu |
Line 487 library. If this is what you want to do
|
Line 489 library. If this is what you want to do
|
Public License instead of this License. |
Public License instead of this License. |
|
|
@iftex |
@iftex |
|
@node Preface |
|
@comment node-name, next, previous, up |
@unnumbered Preface |
@unnumbered Preface |
|
@cindex Preface |
This manual documents Gforth. The reader is expected to know |
This manual documents Gforth. The reader is expected to know |
Forth. This manual is primarily a reference manual. @xref{Other Books} |
Forth. This manual is primarily a reference manual. @xref{Other Books} |
for introductory material. |
for introductory material. |
Line 555 can also get it from Global Engineering
|
Line 560 can also get it from Global Engineering
|
for publication is available electronically and for free in some MS Word |
for publication is available electronically and for free in some MS Word |
format, and it has been converted to HTML. Some pointers to these |
format, and it has been converted to HTML. Some pointers to these |
versions can be found through |
versions can be found through |
http://www.complang.tuwien.ac.at/projects/forth.html. |
@*@file{http://www.complang.tuwien.ac.at/projects/forth.html}. |
|
|
@cite{Forth: The new model} by Jack Woehr (Prentice-Hall, 1993) is an |
@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 |
Line 1136 system that only supplies @code{THEN} is
|
Line 1141 system that only supplies @code{THEN} is
|
Forth's @code{THEN} has the meaning 2b, whereas @code{THEN} in Pascal |
Forth's @code{THEN} has the meaning 2b, whereas @code{THEN} in Pascal |
and many other programming languages has the meaning 3d.] |
and many other programming languages has the meaning 3d.] |
|
|
We also provide the words @code{?dup-if} and @code{?dup-0=-if}, so you |
Gforth also provides the words @code{?dup-if} and @code{?dup-0=-if}, so |
can avoid using @code{?dup}. |
you can avoid using @code{?dup}. Using these alternatives is also more |
|
efficient than using @code{?dup}. Definitions in plain standard Forth |
|
for @code{ENDIF}, @code{?DUP-IF} and @code{?DUP-0=-IF} are provided in |
|
@file{compat/control.fs}. |
|
|
@example |
@example |
@var{n} |
@var{n} |
Line 1229 arithmetic). This behaviour is usually n
|
Line 1237 arithmetic). This behaviour is usually n
|
Gforth offers @code{+DO} and @code{U+DO} (as replacements for |
Gforth offers @code{+DO} and @code{U+DO} (as replacements for |
@code{?DO}), which do not enter the loop if @var{start} is greater than |
@code{?DO}), which do not enter the loop if @var{start} is greater than |
@var{limit}; @code{+DO} is for signed loop parameters, @code{U+DO} for |
@var{limit}; @code{+DO} is for signed loop parameters, @code{U+DO} for |
unsigned loop parameters. These words can be implemented easily on |
unsigned loop parameters. |
standard systems, so using them does not make your programs hard to |
|
port; e.g.: |
|
@example |
|
: +DO ( compile-time: -- do-sys; run-time: n1 n2 -- ) |
|
POSTPONE over POSTPONE min POSTPONE ?DO ; immediate |
|
@end example |
|
|
|
@code{LOOP} can be replaced with @code{@var{n} +LOOP}; this updates the |
@code{LOOP} can be replaced with @code{@var{n} +LOOP}; this updates the |
index by @var{n} instead of by 1. The loop is terminated when the border |
index by @var{n} instead of by 1. The loop is terminated when the border |
Line 1263 between @var{limit+1} and @var{limit} is
|
Line 1265 between @var{limit+1} and @var{limit} is
|
|
|
@code{ 0 0 -DO i . 1 -LOOP} prints nothing |
@code{ 0 0 -DO i . 1 -LOOP} prints nothing |
|
|
Another alternative is @code{@var{n} S+LOOP}, where the negative |
Unfortunately, @code{+DO}, @code{U+DO}, @code{-DO}, @code{U-DO} and |
case behaves symmetrical to the positive case: |
@code{-LOOP} are not in the ANS Forth standard. However, an |
|
implementation for these words that uses only standard words is provided |
@code{-2 0 -DO i . -1 S+LOOP} prints @code{0 -1} |
in @file{compat/loops.fs}. |
|
|
The loop is terminated when the border between @var{limit@minus{}sgn(n)} |
|
and @var{limit} is crossed. Unfortunately, neither @code{-LOOP} nor |
|
@code{S+LOOP} are part of the ANS Forth standard, and they are not easy |
|
to implement using standard words. If you want to write standard |
|
programs, just avoid counting down. |
|
|
|
@code{?DO} can also be replaced by @code{DO}. @code{DO} always enters |
@code{?DO} can also be replaced by @code{DO}. @code{DO} always enters |
the loop, independent of the loop parameters. Do not use @code{DO}, even |
the loop, independent of the loop parameters. Do not use @code{DO}, even |
Line 1295 This is the preferred loop of native cod
|
Line 1291 This is the preferred loop of native cod
|
lazy to optimize @code{?DO} loops properly. In Gforth, this loop |
lazy to optimize @code{?DO} loops properly. In Gforth, this loop |
iterates @var{n+1} times; @code{i} produces values starting with @var{n} |
iterates @var{n+1} times; @code{i} produces values starting with @var{n} |
and ending with 0. Other Forth systems may behave differently, even if |
and ending with 0. Other Forth systems may behave differently, even if |
they support @code{FOR} loops. |
they support @code{FOR} loops. To avoid problems, don't use @code{FOR} |
|
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 |
Line 1331 doc-else
|
Line 1328 doc-else
|
doc-while |
doc-while |
doc-repeat |
doc-repeat |
|
|
|
Gforth adds some more control-structure words: |
|
|
|
doc-endif |
|
doc-?dup-if |
|
doc-?dup-0=-if |
|
|
Counted loop words constitute a separate group of words: |
Counted loop words constitute a separate group of words: |
|
|
doc-?do |
doc-?do |
Line 1341 doc-u-do
|
Line 1344 doc-u-do
|
doc-do |
doc-do |
doc-for |
doc-for |
doc-loop |
doc-loop |
doc-s+loop |
|
doc-+loop |
doc-+loop |
doc--loop |
doc--loop |
doc-next |
doc-next |
Line 1406 while
|
Line 1408 while
|
repeat |
repeat |
@end example |
@end example |
|
|
That's much easier to read, isn't it? Of course, @code{BEGIN} and |
That's much easier to read, isn't it? Of course, @code{REPEAT} and |
@code{WHILE} are predefined, so in this example it would not be |
@code{WHILE} are predefined, so in this example it would not be |
necessary to define them. |
necessary to define them. |
|
|
Line 1440 laden with restrictions. Therefore, we p
|
Line 1442 laden with restrictions. Therefore, we p
|
locals wordset, but also our own, more powerful locals wordset (we |
locals wordset, but also our own, more powerful locals wordset (we |
implemented the ANS Forth locals wordset through our locals wordset). |
implemented the ANS Forth locals wordset through our locals wordset). |
|
|
|
The ideas in this section have also been published in the paper |
|
@cite{Automatic Scoping of Local Variables} by M. Anton Ertl, presented |
|
at EuroForth '94; it is available at |
|
@*@file{http://www.complang.tuwien.ac.at/papers/ertl94l.ps.gz}. |
|
|
@menu |
@menu |
* Gforth locals:: |
* Gforth locals:: |
* ANS Forth locals:: |
* ANS Forth locals:: |
Line 1726 E.g., a definition using @code{TO} might
|
Line 1733 E.g., a definition using @code{TO} might
|
: strcmp @{ addr1 u1 addr2 u2 -- n @} |
: strcmp @{ addr1 u1 addr2 u2 -- n @} |
u1 u2 min 0 |
u1 u2 min 0 |
?do |
?do |
addr1 c@ addr2 c@ - ?dup |
addr1 c@ addr2 c@ - |
if |
?dup-if |
unloop exit |
unloop exit |
then |
then |
addr1 char+ TO addr1 |
addr1 char+ TO addr1 |
Line 1749 are initialized with the right value for
|
Line 1756 are initialized with the right value for
|
addr1 addr2 |
addr1 addr2 |
u1 u2 min 0 |
u1 u2 min 0 |
?do @{ s1 s2 @} |
?do @{ s1 s2 @} |
s1 c@ s2 c@ - ?dup |
s1 c@ s2 c@ - |
if |
?dup-if |
unloop exit |
unloop exit |
then |
then |
s1 char+ s2 char+ |
s1 char+ s2 char+ |
Line 1929 name produces their value. Their value c
|
Line 1936 name produces their value. Their value c
|
|
|
Since this syntax is supported by Gforth directly, you need not do |
Since this syntax is supported by Gforth directly, you need not do |
anything to use it. If you want to port a program using this syntax to |
anything to use it. If you want to port a program using this syntax to |
another ANS Forth system, use @file{anslocal.fs} to implement the syntax |
another ANS Forth system, use @file{compat/anslocal.fs} to implement the |
on the other system. |
syntax on the other system. |
|
|
Note that a syntax shown in the standard, section A.13 looks |
Note that a syntax shown in the standard, section A.13 looks |
similar, but is quite different in having the order of locals |
similar, but is quite different in having the order of locals |
Line 2079 machine code), and for defining the the
|
Line 2086 machine code), and for defining the the
|
nature of Gforth poses a few problems: First of all. Gforth runs on |
nature of Gforth poses a few problems: First of all. Gforth runs on |
several architectures, so it can provide no standard assembler. What's |
several architectures, so it can provide no standard assembler. What's |
worse is that the register allocation not only depends on the processor, |
worse is that the register allocation not only depends on the processor, |
but also on the gcc version and options used. |
but also on the @code{gcc} version and options used. |
|
|
The words Gforth offers encapsulate some system dependences (e.g., the |
The words that Gforth offers encapsulate some system dependences (e.g., the |
header structure), so a system-independent assembler may be used in |
header structure), so a system-independent assembler may be used in |
Gforth. If you do not have an assembler, you can compile machine code |
Gforth. If you do not have an assembler, you can compile machine code |
directly with @code{,} and @code{c,}. |
directly with @code{,} and @code{c,}. |
Line 2099 These words are rarely used. Therefore t
|
Line 2106 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}. |
|
|
|
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 for temporary storage. Unfortunately, the register allocation |
|
is installation-dependent. |
|
|
|
The easiest solution is to use explicit register declarations |
|
(@pxref{Explicit Reg Vars, , Variables in Specified Registers, gcc.info, |
|
GNU C Manual}) for all of the inner interpreter's registers: You have to |
|
compile Gforth with @code{-DFORCE_REG} (configure option |
|
@code{--enable-force-reg}) and the appropriate declarations must be |
|
present in the @code{machine.h} file (see @code{mips.h} for an example; |
|
you can find a full list of all declarable register symbols with |
|
@code{grep register engine.c}). If you give explicit registers to all |
|
variables that are declared at the beginning of @code{engine()}, you |
|
should be able to use the other caller-saved registers for temporary |
|
storage. Alternatively, you can use the @code{gcc} option |
|
@code{-ffixed-REG} (@pxref{Code Gen Options, , Options for Code |
|
Generation Conventions, gcc.info, GNU C Manual}) to reserve a register |
|
(however, this restriction on register allocation may slow Gforth |
|
significantly). |
|
|
|
If this solution is not viable (e.g., because @code{gcc} does not allow |
|
you to explicitly declare all the registers you need), you have to find |
|
out by looking at the code where the inner interpreter's registers |
|
reside and which registers can be used for temporary storage. You can |
|
get an assembly listing of the engine's code with @code{make engine.s}. |
|
|
|
In any case, it is good practice to abstract your assembly code from the |
|
actual register allocation. E.g., if the data stack pointer resides in |
|
register @code{$17}, create an alias for this register called @code{sp}, |
|
and use that in your assembly code. |
|
|
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}, defining words (for fast |
words you just have to edit @file{primitives}, defining words (for fast |
defined words) probably require changes in @file{engine.c}, |
defined words) may require changes in @file{engine.c}, |
@file{kernal.fs}, @file{prims2x.fs}, and possibly @file{cross.fs}. |
@file{kernal.fs}, @file{prims2x.fs}, and possibly @file{cross.fs}. |
|
|
|
|
Line 2375 characters is determined by the locale y
|
Line 2414 characters is determined by the locale y
|
|
|
@item division rounding: |
@item division rounding: |
installation dependent. @code{s" floored" environment? drop .}. We leave |
installation dependent. @code{s" floored" environment? drop .}. We leave |
the choice to 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 to use |
@code{fm/mod}, @code{sm/rem} or simply @code{/}). |
@code{fm/mod}, @code{sm/rem} or simply @code{/}). |
|
|
@item values of @code{STATE} when true: |
@item values of @code{STATE} when true: |
Line 2486 The next invocation of a parsing word re
|
Line 2525 The next invocation of a parsing word re
|
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}: |
!!???If the argument input source is a valid input source then it gets |
@code{-12 THROW}. Note that, once an input file is closed (e.g., because |
restored. Otherwise causes @code{-12 THROW}, which, unless caught, issues |
the end of the file was reached), its source-id may be |
the message "argument type mismatch" and aborts. |
reused. Therefore, restoring an input source specification referencing a |
|
closed file may lead to unpredictable results instead of a @code{-12 |
|
THROW}. |
|
|
|
In the future, Gforth may be able to retore input source specifications |
|
from other than the current input soruce. |
|
|
@item data space containing definitions gets de-allocated: |
@item data space containing definitions gets de-allocated: |
Deallocation with @code{allot} is not checked. This typically resuls in |
Deallocation with @code{allot} is not checked. This typically resuls in |
Line 2560 Not checked. As usual, you can expect me
|
Line 2604 Not checked. As usual, you can expect me
|
None. |
None. |
|
|
@item operator's terminal facilities available: |
@item operator's terminal facilities available: |
!!?? |
After processing the command line, Gforth goes into interactive mode, |
|
and you can give commands to Gforth interactively. The actual facilities |
|
available depend on how you invoke Gforth. |
|
|
@item program data space available: |
@item program data space available: |
@code{sp@ here - .} gives the space remaining for dictionary and data |
@code{sp@ here - .} gives the space remaining for dictionary and data |
stack together. |
stack together. |
|
|
@item return stack space available: |
@item return stack space available: |
!!?? |
By default 16 KBytes. The default can be overridden with the @code{-r} |
|
switch (@pxref{Invocation}) when Gforth starts up. |
|
|
@item stack space available: |
@item stack space available: |
@code{sp@ here - .} gives the space remaining for dictionary and data |
@code{sp@ here - .} gives the space remaining for dictionary and data |
Line 2888 System dependent; @code{REPRESENT} is im
|
Line 2935 System dependent; @code{REPRESENT} is im
|
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: |
What's the question?!! |
System dependent; the rounding behaviour is inherited from the hosting C |
|
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 |
|
bit of the mantissa is 0). |
|
|
@item size of floating-point stack: |
@item size of floating-point stack: |
@code{s" FLOATING-STACK" environment? drop .}. Can be changed at startup |
@code{s" FLOATING-STACK" environment? drop .}. Can be changed at startup |
Line 3190 Also, if you @code{include} @file{etags.
|
Line 3240 Also, if you @code{include} @file{etags.
|
contains the definitions of all words defined afterwards. You can then |
contains the definitions of all words defined afterwards. You can then |
find the source for a word using @kbd{M-.}. Note that emacs can use |
find the source for a word using @kbd{M-.}. Note that emacs can use |
several tags files at the same time (e.g., one for the Gforth sources |
several tags files at the same time (e.g., one for the Gforth sources |
and one for your program). |
and one for your program, @pxref{Select Tags Table,,Selecting a Tags |
|
Table,emacs, Emacs Manual}). The TAGS file for the preloaded words is |
|
@file{$(datadir)/gforth/$(VERSION)/TAGS} (e.g., |
|
@file{/usr/local/share/gforth/0.2/TAGS}). |
|
|
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 3206 file:
|
Line 3259 file:
|
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. |
should be helpful for finding your way in the Gforth sources. |
|
|
|
The ideas in this section have also been published in the papers |
|
@cite{ANS fig/GNU/??? Forth} (in German) by Bernd Paysan, presented at |
|
the Forth-Tagung '93 and @cite{A Portable Forth Engine} by M. Anton |
|
Ertl, presented at EuroForth '93; the latter is available at |
|
@*@file{http://www.complang.tuwien.ac.at/papers/ertl93.ps.Z}. |
|
|
@menu |
@menu |
* Portability:: |
* Portability:: |
* Threading:: |
* Threading:: |
Line 3240 GNU C Manual}). Its labels as values fea
|
Line 3299 GNU C Manual}). Its labels as values fea
|
Labels as Values, gcc.info, GNU C Manual}) makes direct and indirect |
Labels as Values, gcc.info, GNU C Manual}) makes direct and indirect |
threading possible, its @code{long long} type (@pxref{Long Long, , |
threading possible, its @code{long long} type (@pxref{Long Long, , |
Double-Word Integers, gcc.info, GNU C Manual}) corresponds to Forths |
Double-Word Integers, gcc.info, GNU C Manual}) corresponds to Forths |
double numbers. GNU C is available for free on all important (and many |
double numbers@footnote{Unfortunately, long longs are not implemented |
unimportant) UNIX machines, VMS, 80386s running MS-DOS, the Amiga, and |
properly on all machines (e.g., on alpha-osf1, long longs are only 64 |
the Atari ST, so a Forth written in GNU C can run on all these |
bits, the same size as longs (and pointers), but they should be twice as |
machines. |
long according to @ref{Long Long, , Double-Word Integers, gcc.info, GNU |
|
C Manual}). So, we had to implement doubles in C after all. Still, on |
|
most machines we can use long longs and achieve better performance than |
|
with the emulation package.}. GNU C is available for free on all |
|
important (and many unimportant) UNIX machines, VMS, 80386s running |
|
MS-DOS, the Amiga, and the Atari ST, so a Forth written in GNU C can run |
|
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 |
Line 3593 Sieve benchmark on a 486DX2/66 than Gfor
|
Line 3658 Sieve benchmark on a 486DX2/66 than Gfor
|
|
|
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 (compiled with @code{gcc-2.6.3} and @code{-DFORCE_REG}) with |
Gforth (direct threaded, compiled with @code{gcc-2.6.3} and |
Win32Forth 1.2093 and LMI's NT Forth (Beta, May 1994), two systems |
@code{-DFORCE_REG}) with Win32Forth 1.2093, LMI's NT Forth (Beta, May |
written in assembly, and with two systems written in C: PFE-0.9.11 |
1994) and Eforth (with and without peephole (aka pinhole) optimization |
(compiled with @code{gcc-2.6.3} with the default configuration for |
of the threaded code); all these systems were written in assembly |
Linux: @code{-O2 -fomit-frame-pointer -DUSE_REGS}) and ThisForth Beta |
language. We also compared Gforth with three systems written in C: |
(compiled with gcc-2.6.3 -O3 -fomit-frame-pointer). We benchmarked |
PFE-0.9.14 (compiled with @code{gcc-2.6.3} with the default |
Gforth, PFE and ThisForth on a 486DX2/66 under Linux. Kenneth O'Heskin |
configuration for Linux: @code{-O2 -fomit-frame-pointer -DUSE_REGS |
kindly provided the results for Win32Forth and NT Forth on a 486DX2/66 |
-DUNROLL_NEXT}), ThisForth Beta (compiled with gcc-2.6.3 -O3 |
with similar memory performance under Windows NT. |
-fomit-frame-pointer; ThisForth employs peephole optimization of the |
|
threaded code) and TILE (compiled with @code{make opt}). We benchmarked |
|
Gforth, PFE, ThisForth and TILE on a 486DX2/66 under Linux. Kenneth |
|
O'Heskin kindly provided the results for Win32Forth and NT Forth on a |
|
486DX2/66 with similar memory performance under Windows NT. Marcel |
|
Hendrix ported Eforth to Linux, then extended it to run the benchmarks, |
|
added the peephole optimizer, ran the benchmarks and reported the |
|
results. |
|
|
We used four small benchmarks: the ubiquitous Sieve; bubble-sorting and |
We used four small benchmarks: the ubiquitous Sieve; bubble-sorting and |
matrix multiplication come from the Stanford integer benchmarks and have |
matrix multiplication come from the Stanford integer benchmarks and have |
been translated into Forth by Martin Fraeman; we used the versions |
been translated into Forth by Martin Fraeman; we used the versions |
included in the TILE Forth package; and a recursive Fibonacci number |
included in the TILE Forth package, but with bigger data set sizes; and |
computation for benchmark calling performance. The following table shows |
a recursive Fibonacci number computation for benchmarking calling |
the time taken for the benchmarks scaled by the time taken by Gforth (in |
performance. The following table shows the time taken for the benchmarks |
other words, it shows the speedup factor that Gforth achieved over the |
scaled by the time taken by Gforth (in other words, it shows the speedup |
other systems). |
factor that Gforth achieved over the other systems). |
|
|
@example |
@example |
relative Win32- NT This- |
relative Win32- NT eforth This- |
time Gforth Forth Forth PFE Forth |
time Gforth Forth Forth eforth +opt PFE Forth TILE |
sieve 1.00 1.30 1.07 1.67 2.98 |
sieve 1.00 1.39 1.14 1.39 0.85 1.58 3.18 8.58 |
bubble 1.00 1.30 1.40 1.66 |
bubble 1.00 1.31 1.41 1.48 0.88 1.50 3.88 |
matmul 1.00 1.40 1.29 2.24 |
matmul 1.00 1.47 1.35 1.46 1.16 1.58 4.09 |
fib 1.00 1.44 1.26 1.82 2.82 |
fib 1.00 1.52 1.34 1.22 1.13 1.74 2.99 4.30 |
@end example |
@end example |
|
|
You may find the good performance of Gforth compared with the systems |
You may find the good performance of Gforth compared with the systems |
Line 3630 method for relocating the Forth image: l
|
Line 3702 method for relocating the Forth image: l
|
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{System Architecture}). |
|
|
The speedup of Gforth over PFE and ThisForth can be easily explained |
Only Eforth with the peephole optimizer performs comparable to |
with the self-imposed restriction to standard C (although the measured |
Gforth. The speedups achieved with peephole optimization of threaded |
implementation of PFE uses a GNU C extension: global register |
code are quite remarkable. Adding a peephole optimizer to Gforth should |
variables), which makes efficient threading impossible. Moreover, |
cause similar speedups. |
current C compilers have a hard time optimizing other aspects of the |
|
ThisForth source. |
The speedup of Gforth over PFE, ThisForth and TILE can be easily |
|
explained with the self-imposed restriction to standard C, which makes |
|
efficient threading impossible (however, the measured implementation of |
|
PFE uses a GNU C extension: @ref{Global Reg Vars, , Defining Global |
|
Register Variables, gcc.info, GNU C Manual}). Moreover, current C |
|
compilers have a hard time optimizing other aspects of the ThisForth |
|
and the TILE source. |
|
|
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 3644 machine registers by itself and would no
|
Line 3722 machine registers by itself and would no
|
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. |
|
|
@node Bugs, Pedigree, Internals, Top |
In @cite{Translating Forth to Efficient C} by M. Anton Ertl and Martin |
|
Maierhofer (presented at EuroForth '95), an indirect threaded version of |
|
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 |
|
used here. The paper available at |
|
@*@file{http://www.complang.tuwien.ac.at/papers/ertl&maierhofer95.ps.gz}; |
|
it also contains numbers for some native code systems. You can find |
|
numbers for Gforth on various machines in @file{Benchres}. |
|
|
|
@node Bugs, Origin, Internals, Top |
@chapter Bugs |
@chapter Bugs |
|
|
Known bugs are described in the file BUGS in the Gforth distribution. |
Known bugs are described in the file BUGS in the Gforth distribution. |
|
|
If you find a bug, please send a bug report to !!. A bug report should |
If you find a bug, please send a bug report to |
|
@code{bug-gforth@@gnu.ai.mit.edu}. A bug report should |
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 (!! a way to find them out), and a complete list of |
installation options (send the @code{config.status} file), and a |
changes you (or your installer) have made to the Gforth sources (if |
complete list of changes you (or your installer) have made to the Gforth |
any); it should contain a program (or a sequence of keyboard commands) |
sources (if any); it should contain a program (or a sequence of keyboard |
that reproduces the bug and a description of what you think constitutes |
commands) that reproduces the bug and a description of what you think |
the buggy behaviour. |
constitutes the buggy behaviour. |
|
|
For a thorough guide on reporting bugs read @ref{Bug Reporting, , How |
For a thorough guide on reporting bugs read @ref{Bug Reporting, , How |
to Report Bugs, gcc.info, GNU C Manual}. |
to Report Bugs, gcc.info, GNU C Manual}. |
|
|
|
|
@node Pedigree, Word Index, Bugs, Top |
@node Origin, Word Index, Bugs, Top |
@chapter Pedigree |
@chapter Authors and Ancestors of Gforth |
|
|
Gforth descends from BigForth (1993) and fig-Forth. Gforth and PFE (by |
@section Authors and Contributors |
Dirk Zoller) will cross-fertilize each other. Of course, a significant part of the design of Gforth was prescribed by ANS Forth. |
|
|
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 |
|
one of Gforth's first users, in mid-1993) and Stuart Ramsden inspired us |
|
with their continuous feedback. Lennart Benshop contributed |
|
@file{glosgen.fs}, while Stuart Ramsden has been working on automatic |
|
support for calling C libraries. Helpful comments also came from Paul |
|
Kleinrubatscher, Christian Pirker, Dirk Zoller and Marcel Hendrix. |
|
|
|
Gforth also owes a lot to the authors of the tools we used (GCC, CVS, |
|
and autoconf, among others), and to the creators of the Internet: Gforth |
|
was developed across the Internet, and its authors have not met |
|
physically yet. |
|
|
Bernd Paysan wrote BigForth, a child of VolksForth. |
@section Pedigree |
|
|
|
Gforth descends from BigForth (1993) and fig-Forth. Gforth and PFE (by |
|
Dirk Zoller) will cross-fertilize each other. Of course, a significant |
|
part of the design of Gforth was prescribed by ANS Forth. |
|
|
VolksForth descends from F83. !! Authors? When? |
Bernd Paysan wrote BigForth, a descendent from TurboForth, an unreleased |
|
32 bit native code version of VolksForth for the Atari ST, written |
|
mostly by Dietrich Weineck. |
|
|
|
VolksForth descends from F83. It was written by Klaus Schleisiek, Bernd |
|
Pennemann, Georg Rehfeld and Dietrich Weineck for the C64 (called |
|
UltraForth there) in the mid-80s and ported to the Atari ST in 1986. |
|
|
Laxen and Perry wrote F83 as a model implementation of the |
Hennry Laxen and Mike Perry wrote F83 as a model implementation of the |
Forth-83 standard. !! Pedigree? When? |
Forth-83 standard. !! Pedigree? When? |
|
|
A team led by Bill Ragsdale implemented fig-Forth on many processors in |
A team led by Bill Ragsdale implemented fig-Forth on many processors in |
1979. Dean Sanderson and Bill Ragsdale developed the original |
1979. Robert Selzer and Bill Ragsdale developed the original |
implementation of fig-Forth based on microForth. |
implementation of fig-Forth for the 6502 based on microForth. |
|
|
!! microForth pedigree |
The principal architect of microForth was Dean Sanderson. microForth was |
|
FORTH, Inc.'s first off-the-shelf product. It was developped in 1976 for |
|
the 1802, and subsequently implemented on the 8080, the 6800 and the |
|
Z80. |
|
|
|
All earlier Forth systems were custom-made, usually by Charles Moore, |
|
who discovered (as he puts it) Forth during the late 60s. The first full |
|
Forth existed in 1971. |
|
|
A part of the information in this section comes from @cite{The Evolution |
A part of the information in this section comes from @cite{The Evolution |
of Forth} by Elizabeth D. Rather, Donald R. Colburn and Charles |
of Forth} by Elizabeth D. Rather, Donald R. Colburn and Charles |
Line 3688 H. Moore, presented at the HOPL-II confe
|
Line 3805 H. Moore, presented at the HOPL-II confe
|
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. |
|
|
@node Word Index, Node Index, Pedigree, Top |
@node Word Index, Node Index, Origin, Top |
@chapter Word Index |
@chapter Word Index |
|
|
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 |