--- gforth/Attic/gforth.ds 1996/01/07 17:22:09 1.29 +++ gforth/Attic/gforth.ds 1996/09/10 16:08:37 1.35 @@ -7,9 +7,9 @@ @comment %**end of header (This is for running Texinfo on a region.) @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 this manual provided the copyright notice and this permission notice @@ -41,7 +41,7 @@ Copyright @copyright{} 1995 Free Softwar @sp 10 @center @titlefont{Gforth Manual} @sp 2 -@center for version 0.1 +@center for version 0.2 @sp 2 @center Anton Ertl @center Bernd Paysan @@ -51,7 +51,7 @@ Copyright @copyright{} 1995 Free Softwar @comment The following two commands start the copyright page. @page @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 ... @@ -77,7 +77,7 @@ Copyright @copyright{} 1995 Free Softwar @node Top, License, (dir), (dir) @ifinfo 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 @menu @@ -88,6 +88,7 @@ personal machines. This manual correspon * Words:: Forth words available in Gforth * ANS conformance:: Implementation-defined options etc. * Model:: The abstract machine of Gforth +* Integrating Gforth:: Forth as scripting language for applications. * Emacs and Gforth:: The Gforth Mode * Internals:: Implementation details * Bugs:: How to report them @@ -848,7 +849,7 @@ The format of floating point numbers rec interpreter is: a signed decimal number, possibly containing a decimal point (@code{.}), followed by @code{E} or @code{e}, optionally followed by a signed integer (the exponent). E.g., @code{1e} ist the same as -@code{+1.0e+1}. Note that a number without @code{e} +@code{+1.0e+0}. Note that a number without @code{e} is not interpreted as floating-point number, but as double (if the number contains a @code{.}) or single precision integer. Also, conversions between string and floating point numbers always use base @@ -1141,8 +1142,11 @@ system that only supplies @code{THEN} is Forth's @code{THEN} has the meaning 2b, whereas @code{THEN} in Pascal and many other programming languages has the meaning 3d.] -We also provide the words @code{?dup-if} and @code{?dup-0=-if}, so you -can avoid using @code{?dup}. +Gforth also provides the words @code{?dup-if} and @code{?dup-0=-if}, so +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 @var{n} @@ -1234,13 +1238,7 @@ arithmetic). This behaviour is usually n 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 @var{limit}; @code{+DO} is for signed loop parameters, @code{U+DO} for -unsigned loop parameters. These words can be implemented easily on -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 +unsigned loop parameters. @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 @@ -1268,16 +1266,10 @@ between @var{limit+1} and @var{limit} is @code{ 0 0 -DO i . 1 -LOOP} prints nothing -Another alternative is @code{@var{n} S+LOOP}, where the negative -case behaves symmetrical to the positive case: - -@code{-2 0 -DO i . -1 S+LOOP} prints @code{0 -1} - -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. +Unfortunately, @code{+DO}, @code{U+DO}, @code{-DO}, @code{U-DO} and +@code{-LOOP} are not in the ANS Forth standard. However, an +implementation for these words that uses only standard words is provided +in @file{compat/loops.fs}. @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 @@ -1300,7 +1292,8 @@ This is the preferred loop of native cod lazy to optimize @code{?DO} loops properly. In Gforth, this loop 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 -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 @subsection Arbitrary control structures @@ -1336,6 +1329,12 @@ doc-else doc-while 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: doc-?do @@ -1346,7 +1345,6 @@ doc-u-do doc-do doc-for doc-loop -doc-s+loop doc-+loop doc--loop doc-next @@ -1411,7 +1409,7 @@ while repeat @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 necessary to define them. @@ -1736,8 +1734,8 @@ E.g., a definition using @code{TO} might : strcmp @{ addr1 u1 addr2 u2 -- n @} u1 u2 min 0 ?do - addr1 c@ addr2 c@ - ?dup - if + addr1 c@ addr2 c@ - + ?dup-if unloop exit then addr1 char+ TO addr1 @@ -1759,8 +1757,8 @@ are initialized with the right value for addr1 addr2 u1 u2 min 0 ?do @{ s1 s2 @} - s1 c@ s2 c@ - ?dup - if + s1 c@ s2 c@ - + ?dup-if unloop exit then s1 char+ s2 char+ @@ -1933,14 +1931,14 @@ stack easier. The whole definition must be in one line. @end itemize -Locals defined in this way behave like @code{VALUE}s -(@xref{Values}). I.e., they are initialized from the stack. Using their +Locals defined in this way behave like @code{VALUE}s (@xref{Simple +Defining Words}). I.e., they are initialized from the stack. Using their name produces their value. Their value can be changed using @code{TO}. 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 -another ANS Forth system, use @file{anslocal.fs} to implement the syntax -on the other system. +another ANS Forth system, use @file{compat/anslocal.fs} to implement the +syntax on the other system. Note that a syntax shown in the standard, section A.13 looks similar, but is quite different in having the order of locals @@ -1963,11 +1961,247 @@ locals wordset. @section Defining Words @menu -* Values:: +* Simple Defining Words:: +* Colon Definitions:: +* User-defined Defining Words:: +* Supplying names:: +* Interpretation and Compilation Semantics:: @end menu -@node Values, , Defining Words, Defining Words -@subsection Values +@node Simple Defining Words, Colon Definitions, Defining Words, Defining Words +@subsection Simple Defining Words + +doc-constant +doc-2constant +doc-fconstant +doc-variable +doc-2variable +doc-fvariable +doc-create +doc-user +doc-value +doc-to +doc-defer +doc-is + +@node Colon Definitions, User-defined Defining Words, Simple Defining Words, Defining Words +@subsection Colon Definitions + +@example +: name ( ... -- ... ) + word1 word2 word3 ; +@end example + +creates a word called @code{name}, that, upon execution, executes +@code{word1 word2 word3}. @code{name} is a @dfn{(colon) definition}. + +The explanation above is somewhat superficial. @xref{Interpretation and +Compilation Semantics} for an in-depth discussion of some of the issues +involved. + +doc-: +doc-; + +@node User-defined Defining Words, Supplying names, Colon Definitions, Defining Words +@subsection User-defined Defining Words + +You can create new defining words simply by wrapping defining-time code +around existing defining words and putting the sequence in a colon +definition. + +If you want the words defined by your defining words to behave +differently than words defined with standard defining words, you can +write your defining word like this: + +@example +: def-word ( "name" -- ) + Create @var{code1} +DOES> ( ... -- ... ) + @var{code2} ; + +def-word name +@end example + +Technically, this fragment defines a defining word @code{def-word}, and +a word @code{name}; when you execute @code{name}, the address of the +body of @code{name} is put on the data stack and @var{code2} is executed +(the address of the body of @code{name} is the address @code{HERE} +returns immediately after the @code{CREATE}). E.g., you can implement +@code{Constant} in this way: + +@example +: constant ( w "name" -- ) + create , +DOES> ( -- w ) + @ ; +@end example + +When you create a constant with @code{5 constant five}, first a new word +@code{five} is created, then the value 5 is laid down in the body 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. + +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 +following code (the following code expects the address of the body on +the top of stack, which is not reflected in the stack comment). This is +the convention that I use and recommend (it clashes a bit with using +locals declarations for stack effect specification, though). + +@subsubsection Applications of @code{CREATE..DOES>} + +You may not be sure how to use this feature. Here are some usage +patterns: + +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 +you see similar colon definitions, you can factor them using +@code{CREATE..DOES>}. E.g., an assembler usually defines several words +that look very similar: +@example +: ori, ( reg-taget reg-source n -- ) + 0 asm-reg-reg-imm ; +: andi, ( reg-taget reg-source n -- ) + 1 asm-reg-reg-imm ; +@end example + +This could be factored with: +@example +: reg-reg-imm ( op-code -- ) + create , +DOES> ( reg-taget reg-source n -- ) + @ asm-reg-reg-imm ; + +0 reg-reg-imm ori, +1 reg-reg-imm andi, +@end example + +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 +the functional language community). E.g., @code{+} needs two +parameters. Creating versions of @code{+} with one parameter fixed can +be done like this: +@example +: curry+ ( n1 -- ) + create , +DOES> ( n2 -- n1+n2 ) + @ + ; + + 3 curry+ 3+ +-2 curry+ 2- +@end example + +@subsubsection The gory details of @code{CREATE..DOES>} + +doc-does> + +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 +definition. This allows us to, e.g., select among different DOES>-parts: +@example +: does1 +DOES> ( ... -- ... ) + ... ; + +: does2 +DOES> ( ... -- ... ) + ... ; + +: def-word ( ... -- ... ) + create ... + IF + does1 + ELSE + does2 + ENDIF ; +@end example + +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 +will override the behaviour of the last word defined in any case. In a +standard program, you can use @code{DOES>} only in a colon +definition. In Gforth, you can also use it in interpretation state, in a +kind of one-shot mode: +@example +CREATE name ( ... -- ... ) + @var{initialization} +DOES> + @var{code} ; +@end example +This is equivalwent to the standard +@example +:noname +DOES> + @var{code} ; +CREATE name EXECUTE ( ... -- ... ) + @var{initialization} +@end example + +You can get the address of the body of a word with + +doc->body + +@node Supplying names, Interpretation and Compilation Semantics, User-defined Defining Words, Defining Words +@subsection Supplying names for the defined words + +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 +can do this with + +doc-nextname + +E.g., + +@example +s" foo" nextname create +@end example +is equivalent to +@example +create foo +@end example + +Sometimes you want to define a word without a name. You can do this with + +doc-noname + +To make any use of the newly defined word, you need its execution +token. You can get it with + +doc-lastxt + +E.g., you can initialize a deferred word with an anonymous colon +definition: +@example +Defer deferred +noname : ( ... -- ... ) + ... ; +lastxt IS deferred +@end example + +@code{lastxt} also works when the last word was not defined as +@code{noname}. + +The standard has also recognized the need for anonymous words and +provides + +doc-:noname + +This leaves the execution token for the word on the stack after the +closing @code{;}. You can rewrite the last example with @code{:noname}: +@example +Defer deferred +:noname ( ... -- ... ) + ... ; +IS deferred +@end example + +@node Interpretation and Compilation Semantics, , Supplying names, Defining Words +@subsection Interpretation and Compilation Semantics + +doc-immediate +doc-interpret/compile: + + @node Wordlists, Files, Defining Words, Words @section Wordlists @@ -2143,9 +2377,10 @@ and use that in your assembly code. Another option for implementing normal and defining words efficiently is: adding the wanted functionality to the source of Gforth. For normal -words you just have to edit @file{primitives}, defining words (for fast -defined words) may require changes in @file{engine.c}, -@file{kernal.fs}, @file{prims2x.fs}, and possibly @file{cross.fs}. +words you just have to edit @file{primitives} (@pxref{Automatic +Generation}), defining words (equivalent to @code{;CODE} words, for fast +defined words) may require changes in @file{engine.c}, @file{kernal.fs}, +@file{prims2x.fs}, and possibly @file{cross.fs}. @node Threading Words, , Assembler and Code words, Words @@ -2176,10 +2411,10 @@ doc-douser: doc-dodefer: doc-dofield: -Currently there is no installation-independent way for recogizing words -defined by a @code{CREATE}...@code{DOES>} word; however, once you know -that a word is defined by a @code{CREATE}...@code{DOES>} word, you can -use @code{>DOES-CODE}. +You can recognize words defined by a @code{CREATE}...@code{DOES>} word +with @code{>DOES-CODE}. If the word was defined in that way, the value +returned is different from 0 and identifies the @code{DOES>} used by the +defining word. @node ANS conformance, Model, Words, Top @chapter ANS conformance @@ -2187,7 +2422,7 @@ use @code{>DOES-CODE}. To the best of our knowledge, Gforth is an ANS Forth System -@itemize +@itemize @bullet @item providing the Core Extensions word set @item providing the Block word set @item providing the Block Extensions word set @@ -2206,7 +2441,7 @@ ANS Forth System @item providing the Memory-Allocation word set @item providing the Memory-Allocation Extensions word set (that one's easy) @item providing the Programming-Tools word set -@item providing @code{;code}, @code{AHEAD}, @code{ASSEMBLER}, @code{BYE}, @code{CODE}, @code{CS-PICK}, @code{CS-ROLL}, @code{STATE}, @code{[ELSE]}, @code{[IF]}, @code{[THEN]} from the Programming-Tools Extensions word set +@item providing @code{;CODE}, @code{AHEAD}, @code{ASSEMBLER}, @code{BYE}, @code{CODE}, @code{CS-PICK}, @code{CS-ROLL}, @code{STATE}, @code{[ELSE]}, @code{[IF]}, @code{[THEN]} from the Programming-Tools Extensions word set @item providing the Search-Order word set @item providing the Search-Order Extensions word set @item providing the String word set @@ -3201,9 +3436,11 @@ Not implemented (yet). @table @i @item changing the compilation wordlist (during compilation): -The definition is put into the wordlist that is the compilation wordlist -when @code{REVEAL} is executed (by @code{;}, @code{DOES>}, -@code{RECURSIVE}, etc.). +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., +@code{immediate}) or the code field (e.g., when executing @code{DOES>}) +are applied to the latest defined word (as reported by @code{last} or +@code{lastxt}), if possible, irrespective of the compilation wordlist. @item search order empty (@code{previous}): @code{abort" Vocstack empty"}. @@ -3213,15 +3450,67 @@ when @code{REVEAL} is executed (by @code @end table - -@node Model, Emacs and Gforth, ANS conformance, Top +@node Model, Integrating Gforth, ANS conformance, Top @chapter Model -@node Emacs and Gforth, Internals, Model, Top +This chapter has yet to be written. It will contain information, on +which internal structures you can rely. + +@node Integrating Gforth, Emacs and Gforth, Model, Top +@chapter Integrating Gforth into C programs + +This is not yet implemented. + +Several people like to use Forth as scripting language for applications +that are otherwise written in C, C++, or some other language. + +The Forth system ATLAST provides facilities for embedding it into +applications; unfortunately it has several disadvantages: most +implorantly, it is not based on ANS Forth, and it is apparently dead +(i.e., not developed further and not supported). The facilities +provided by Gforth in this area are inspired by ATLASTs facilities, so +making the switch should not be hard. + +We also tried to design the interface such that it can easily be +implemented by other Forth systems, so that we may one day arrive at a +standardized interface. Such a standard interface would allow you to +replace the Forth system without having to rewrite C code. + +You embed the Gforth interpreter by linking with the library +@code{libgforth.a} (give the compiler the option @code{-lgforth}). All +global symbols in this library that belong to the interface, have the +prefix @code{forth_}. (Global symbols that are used internally have the +prefix @code{gforth_}). + +You can include the declarations of Forth types and the functions and +variables of the interface with @code{include }. + +Types. + +Variables. + +Data and FP Stack pointer. Area sizes. + +functions. + +forth_init(imagefile) +forth_evaluate(string) exceptions? +forth_goto(address) (or forth_execute(xt)?) +forth_continue() (a corountining mechanism) + +Adding primitives. + +No checking. + +Signals? + +Accessing the Stacks + +@node Emacs and Gforth, Internals, Integrating Gforth, Top @chapter Emacs and Gforth Gforth comes with @file{gforth.el}, an improved version of -@file{forth.el} by Goran Rydqvist (icluded 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 indentation. I have also added comment paragraph filling (@kbd{M-q}), commenting (@kbd{C-x \}) and uncommenting (@kbd{C-u C-x \}) regions and @@ -3246,7 +3535,7 @@ several tags files at the same time (e.g 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}). +@file{/usr/local/share/gforth/0.2.0/TAGS}). To get all these benefits, add the following lines to your @file{.emacs} file: @@ -3301,11 +3590,17 @@ limitations: GNU C, the version of C pro GNU C Manual}). Its labels as values feature (@pxref{Labels as Values, , Labels as Values, gcc.info, GNU C Manual}) makes direct and indirect threading possible, its @code{long long} type (@pxref{Long Long, , -Double-Word Integers, gcc.info, GNU C Manual}) corresponds to Forths -double numbers. 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. +Double-Word Integers, gcc.info, GNU C Manual}) corresponds to Forth's +double numbers@footnote{Unfortunately, long longs are not implemented +properly on all machines (e.g., on alpha-osf1, long longs are only 64 +bits, the same size as longs (and pointers), but they should be twice as +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 is slower than assembly. For our Forth engine we repeatedly looked at @@ -3544,7 +3839,7 @@ An important optimization for stack mach engines, is keeping one or more of the top stack items in registers. If a word has the stack effect @var{in1}...@var{inx} @code{--} @var{out1}...@var{outy}, keeping the top @var{n} items in registers -@itemize +@itemize @bullet @item is better than keeping @var{n-1} items, if @var{x>=n} and @var{y>=n}, due to fewer loads from and stores to the stack. @@ -3578,7 +3873,7 @@ The TOS optimization makes the automatic bit more complicated. Just replacing all occurrences of @code{sp[0]} by @code{TOS} is not sufficient. There are some special cases to consider: -@itemize +@itemize @bullet @item In the case of @code{dup ( w -- w w )} the generator must not eliminate the store to the original location of the item on the stack, if the TOS optimization is turned on. @@ -3659,34 +3954,35 @@ Gforth (direct threaded, compiled with @ @code{-DFORCE_REG}) with Win32Forth 1.2093, LMI's NT Forth (Beta, May 1994) and Eforth (with and without peephole (aka pinhole) optimization of the threaded code); all these systems were written in assembly -language. We also compared Gforth with two systems written in C: -PFE-0.9.11 (compiled with @code{gcc-2.6.3} with the default -configuration for Linux: @code{-O2 -fomit-frame-pointer -DUSE_REGS}) and -ThisForth Beta (compiled with gcc-2.6.3 -O3 -fomit-frame-pointer; -ThisForth employs peephole optimization of the threaded code). We -benchmarked Gforth, PFE and ThisForth 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. +language. We also compared Gforth with three systems written in C: +PFE-0.9.14 (compiled with @code{gcc-2.6.3} with the default +configuration for Linux: @code{-O2 -fomit-frame-pointer -DUSE_REGS +-DUNROLL_NEXT}), ThisForth Beta (compiled with gcc-2.6.3 -O3 +-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 matrix multiplication come from the Stanford integer benchmarks and have been translated into Forth by Martin Fraeman; we used the versions -included in the TILE Forth package; and a recursive Fibonacci number -computation for benchmarking calling performance. The following table shows -the time taken for the benchmarks scaled by the time taken by Gforth (in -other words, it shows the speedup factor that Gforth achieved over the -other systems). +included in the TILE Forth package, but with bigger data set sizes; and +a recursive Fibonacci number computation for benchmarking calling +performance. The following table shows the time taken for the benchmarks +scaled by the time taken by Gforth (in other words, it shows the speedup +factor that Gforth achieved over the other systems). @example -relative Win32- NT eforth This- -time Gforth Forth Forth eforth +opt PFE Forth -sieve 1.00 1.39 1.14 1.39 0.85 1.78 3.18 -bubble 1.00 1.33 1.43 1.51 0.89 1.70 -matmul 1.00 1.43 1.31 1.42 1.12 2.28 -fib 1.00 1.55 1.36 1.24 1.15 1.97 3.04 +relative Win32- NT eforth This- + time Gforth Forth Forth eforth +opt PFE Forth TILE +sieve 1.00 1.39 1.14 1.39 0.85 1.58 3.18 8.58 +bubble 1.00 1.31 1.41 1.48 0.88 1.50 3.88 +matmul 1.00 1.47 1.35 1.46 1.16 1.58 4.09 +fib 1.00 1.52 1.34 1.22 1.13 1.74 2.99 4.30 @end example You may find the good performance of Gforth compared with the systems @@ -3703,12 +3999,13 @@ Gforth. The speedups achieved with peeph code are quite remarkable. Adding a peephole optimizer to Gforth should cause similar speedups. -The speedup of Gforth over PFE and ThisForth can be easily explained -with the self-imposed restriction to standard C (although the measured -implementation of PFE uses a GNU C extension: global register -variables), which makes efficient threading impossible. Moreover, -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 varies widely with the version of @code{gcc} used. E.g., @code{gcc-2.5.8} @@ -3732,7 +4029,7 @@ numbers for Gforth on various machines i Known bugs are described in the file BUGS in the Gforth distribution. If you find a bug, please send a bug report to -@code{gforth-bugs@@mips.complang.tuwien.ac.at}. A bug report should +@code{bug-gforth@@gnu.ai.mit.edu}. A bug report should describe the Gforth version used (it is announced at the start of an interactive Gforth session), the machine and operating system (on Unix systems you can use @code{uname -a} to produce this information), the @@ -3752,13 +4049,18 @@ to Report Bugs, gcc.info, GNU C Manual}. @section Authors and Contributors The Gforth project was started in mid-1992 by Bernd Paysan and Anton -Ertl. The third major author was Jens Wilke. Lennart Benschop (who also -was one of Gforth's first users, in mid-1993) and Stuart Ramsden -inspired us with their continuous feedback. Lennart Benshop contributed +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. + @section Pedigree Gforth descends from BigForth (1993) and fig-Forth. Gforth and PFE (by @@ -3773,7 +4075,7 @@ VolksForth descends from F83. It was wri Pennemann, Georg Rehfeld and Dietrich Weineck for the C64 (called UltraForth there) in the mid-80s and ported to the Atari ST in 1986. -Hennry Laxen and Mike Perry wrote F83 as a model implementation of the +Henry Laxen and Mike Perry wrote F83 as a model implementation of the Forth-83 standard. !! Pedigree? When? A team led by Bill Ragsdale implemented fig-Forth on many processors in @@ -3786,7 +4088,8 @@ the 1802, and subsequently implemented o Z80. All earlier Forth systems were custom-made, usually by Charles Moore, -who discovered (as he puts it) Forth in the late 60s. +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 of Forth} by Elizabeth D. Rather, Donald R. Colburn and Charles