/
meta.txt
1244 lines (977 loc) · 22.6 KB
/
meta.txt
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\ *********************************************************************
\ Meta compiler for generating Xcross compiled code *
\ Filename: meta.txt *
\ Date: 26.03.2021 *
\ Updated: 06.05.2021 *
\ MCU: gForth *
\ Copyright: Marc PETREMANN *
\ Author: Marc PETREMANN *
\ *********************************************************************
cr ." meta.txt"
\ the TARGET vocabulary receives the headers of the words to be compiled in the target
vocabulary target
\ the TRANSITION vocabulary receives words with immediate action during meta-compilation
vocabulary transition
\ the FORWARD vocabulary receives the headers of the reference words before
vocabulary forward
vocabulary Xuser
\ the Xassembler vocabulary receives the Cross Assembler
vocabulary Xassembler
\ meta contains the meta-compiler
vocabulary meta
meta definitions
\ immediate version of only for vocabulary chaining
: [only] ( ---)
only
; immediate
\ immediate version of forth for vocabulary chaining
: [forth] ( ---)
forth
; immediate
\ immediate version of meta for vocabulary chaining
: [meta] ( ---)
meta
; immediate
\ immediate version of Xassembler for vocabulary chaining
: [Xassembler] ( ---)
Xassembler
; immediate
\ create Xswitch ( -- addr )
\ 0 , ( Context )
\ 0 , ( Current )
\
\ 0 value Xswitch-context ( -- Xcontext )
\ 0 value Xswitch-current ( -- Xcurrent )
: (do-switch) ( addr -- )
\ break" switch : " cr
dup @ context @ swap context !
over ! cell + \ ?? 2 + or CELL + ??
dup @ current @ swap current !
swap !
;
\ keeps and restores a context
: switch ( -- )
context @ ,
current @ ,
does>
(do-switch)
;
switch
\ *** new code to replace SWITCH ***************
\ keeps and restores a context
variable context-backup
variable current-backup
\ save CONTEXT and CURRENT in backups
: contextCurrentSave ( -- )
context @ context-backup !
current @ current-backup !
;
\ restore CONTEXT and CURRENT in backups
: contextCurrentRestore ( -- )
context-backup @ context !
current-backup @ current !
;
\ **********************************************
only forth also meta also
root definitions
\ all the following words are also redefined in ROOT
: meta
meta ;
: target
target ;
: transition
transition ;
: forward
forward ;
: Xuser
Xuser ;
: Xassembler
Xassembler ;
only forth also meta also
meta definitions
\ the following words are defined in the META vocabulary
: in-target ( -- ) \ strength definition of words in TARGET
only target definitions \ search order limited to ROOT and TARGET
;
\ force definition of words in target
: in-transition ( -- )
only forward also \ search order:
target definitions \ TRANSITION TARGET FORWARD
also transition
;
\ word definition strength in META
: in-meta ( -- )
only forth also \ search order:
meta definitions also \ META FORTH
;
\ word definition strength in Xassembler
: in-Xassembler ( -- )
only forth also \ search order:
Xassembler definitions also \ XASSEMBLER FORTH
;
\ word definition strength in FORWARDS
: in-forward ( -- )
forward definitions \ order of words starting with FORWARD
;
\ Memory access variables in the target
variable ADR-T \ memorize target address; ADRment-Target
variable DP-T \ and Target offset; Dict.Pointer-Target
\ convert target-addr in physical-address
: taddr-calc ( taddr -- phys-addr)
ADR-T @ +
;
\ get a byte in the target
: c@-t ( taddr -- c )
taddr-calc c@
;
\ get a 16-bit word from the target
: @-t ( taddr -- w )
dup 1+ c@-t $100 *
swap c@-t +
byte-invert
;
\ get 32-bit value in the target - unused
\ : d@-t ( taddr -- d )
\ **** @TODO: à écrire ****
\ ;
\ store a byte in the target
: c!-t ( char taddr -- )
taddr-calc c!
;
\ store a 16-bit word in the target
: !-t { word taddr -- } \ CAUTION: local variables
word byte-invert
$100 /mod swap
taddr c!-t
taddr 1+ c!-t
;
\ target dictionary pointer stacks
: here-t ( -- taddr )
DP-T @
;
\ allocate n bytes in the target
: allot-t ( n -- )
DP-T +!
;
\ Logical OR on one byte in the target
: cset-t { mask taddr -- } \ CAUTION: locals variables
taddr c@-t
mask or
taddr c!-t
;
\ compile a byte in the target
: c,-t ( char -- )
here-t c!-t
1 allot-t
;
\ compile a 16-bit word into the target
: ,-t ( w -- )
here-t !-t
2 allot-t
;
\ compile a string in the target
: string,-t ( addr len -- )
0
?do
count c,-t
loop
drop
;
2 value cell-t
\ if DP-T is odd, increment DP-T
: align ( --)
here-t
cell-t mod
DP-T +!
;
\ Xassembler Meta Xassembler
\ : M?>MARK ( -- f addr )
\ true here-t 0 c,-t
\ ;
\ : M?>RESOLVE ( f addr -- )
\ here-t over 1+ - swap c!-t ?CONDITION
\ ;
\ : M?<MARK ( -- f addr )
\ true here-t
\ ;
\ : M?<RESOLVE ( f addr -- )
\ here-t 1+ - c,-t ?CONDITION
\ ;
\ ' HERE-T Xassembler IS HERE
\ ' M?>MARK Xassembler IS ?>MARK
\ ' M?>RESOLVE Xassembler IS ?>RESOLVE
\ ' M?<MARK Xassembler IS ?<MARK
\ ' M?<RESOLVE Xassembler IS ?<RESOLVE
meta in-meta
\ Variables and work options for metacompiler
variable WIDTH 15 WIDTH ! \ Headers: max name size
variable LAST-T \ Latest nfa compiled
variable CONTEXT-T \ context metavocabulary
variable CURRENT-T \ current metavocabulary
variable CHECKING \ Compilation enslaved
variable FORCE \ Forced compilation
variable VALID VALID on \ Validity of current definition
variable OLD-T \ Old position in target
variable SAVING SAVING off \ Saving option
\ store the destination filename
string TARGET$ \ initialization in meta_XXXXXX.XXX
\ Display of the state of a flag.
: .flag ( adr -- )
@ ?dup \ empile et teste si contenu adr non nul
if \ si non nul,
." ON " \ affiche 'ON'
dup true <> \ teste si <> de 'vrai' (-1)
if \ si <> de -1
." ( " . ." )" \ affiche valeur entre ( et )
else \ sinon supprime valeur parasite
drop
then
else
." OFF" \ si nul, affiche 'OFF'
then
;
\ Displaying meta-compilation options
: .options ( -- )
\ break" debug .options"
cr ." OPTIONS :"
cr FRENCH ?\ ." En-têtes (longueur) WIDTH "
ENGLISH ?\ ." Header (length) WIDTH "
GERMAN ?\ ." Namen (lange) WIDTH "
WIDTH .flag
cr FRENCH ?\ ." Compilation asservie CHECKING "
ENGLISH ?\ ." Controlled compilation CHECKING "
GERMAN ?\ ." Kontrolierte Compilation CHECKING "
CHECKING .flag
cr FRENCH ?\ ." Sauvegarde de la cible SAVING "
ENGLISH ?\ ." Saving the target SAVING "
GERMAN ?\ ." TARGET abspeichern SAVING "
SAVING .flag
cr FRENCH ?\ ." Fichier de sauvegarde TARGET$ "
ENGLISH ?\ ." Output file TARGET$ "
GERMAN ?\ ." Files Name abspeichert in TARGET$ "
TARGET$ $@ type
cr
;
\ Compiling and resolving target or forward references
: make-code ( PFA -- ) \ @TODO: to debug....
\ dup 2 + @
dup cell + @
if
@
else
drop 0
then
,-t
;
: link-backwards ( PFA -- )
VALID @ \ @TODO: to debug....
if
here-t over @ ,-t swap !
else
drop 0 ,-t
then
;
\ test if word in FORWARD is resolved
: resolved? ( cfa -- f )
\ 2 + @ \ @TODO: to debug....
>body @
;
: forward-code ( cfa -- )
dup resolved? \ @TODO: to debug....
if make-code
else link-backwards
then
;
\ create a FORWARD reference
: forward: ( -- )
contextCurrentSave
in-forward
create
contextCurrentSave
0 , 0 , \ @TODO: to debug....
does>
forward-code
;
\ @TODO! xxx à débogguer
: ?missing ( f -- )
if
parse-name type
FRENCH ?\ abort" inconnu"
ENGLISH ?\ abort" I don't understand that!"
GERMAN ?\ abort" unbeknt"
then
;
\ Search in a single vocabulary
: -find ( <mot> -- cfa f )
bl word \ isolate a word in the input stream
find \ search in context voc
;
\ Search in TARGET vocabulary
: tickT ( -- cfa )
CONTEXT @
target
-find rot
CONTEXT ! ;
\ : [TARGET] ( -- ) tickT , ; immediate
\ search in forward vocabulary
: tickF ( -- cfa f )
CONTEXT @
forward
-find rot
CONTEXT !
;
\ force compilation of word in FORWARD vocabulary
: [forward] ( exec: <word> -- )
tickF 0= ?missing
, \ @TODO: ce , doit pas compiler le cfa dans gForth mais le cfa de la cible
; immediate
: resolve ( taddr cfa -- )
>body 2dup true over 2 + ! @
begin
dup
while
2dup @-t -ROT swap !-t
repeat
2DROP !
;
: ?resolves ( -- )
tickF
if
dup >body resolved? 0=
if
here-t swap resolve
else
drop
then
else
drop
then
;
\ Validate definitions in controlled mode
\ Check the validity of a new word
defer ?valid ( -- )
\ Validation on "marked" words from FORTH -- @TODO: à débugger
\ : (?valid) ( -- )
\ CHECKING @
\ if
\ >IN @ CONTEXT @
\ forth -find
\ if
\ >VIEW @ 0<>
\ else
\ drop FALSE
\ then
\ VALID !
\ CONTEXT ! >IN !
\ then
\ ;
: (?valid) ( -- )
true VALID !
;
' (?valid) is ?valid
\ move backward dictionary pointer if invalid word
: ?backstep ( -- )
VALID @
if here-t OLD-T ! \ dictionary pointer target in OLD-T
else OLD-T @ DP-T ! \ brings back target dictionary pointer
then
;
\ returns target dictionary pointer if word is valid
: ?here-t ( -- taddr )
VALID @
if here-t
else 0
then
;
\ Directive for mandatory compilation
: forced ( -- )
?backstep CHECKING @ FORCE !
CHECKING off VALID ON
;
\ Compulsory end of compilation
: unforced ( -- )
FORCE @ CHECKING !
;
\ Création des en-têtes dans la cible
\ : HASH ( str-addr voc-addr -- thread )
\ swap 1+ c@ #THREADS 1- AND 2* +
\ ;
\ *** compilation of complete header word ***************************
defer compile-header
\ compile header into target --- @TODO : à adapter aux en-têtes FlashForth
: header-t ( -- )
bl word
dup
c@ WIDTH @ MIN \ dup
VALID @ AND
if
align
compile-header \ compilation of complete word header
else
drop
then
;
\ Creation in target and target reference with FORWARD auto-resolution
: target-create ( -- )
?backstep
?valid
\ break" target-create : "
>IN @ dup header-t
>IN !
in-target \ create word in target vocabulary
create
in-meta
here-t , VALID @ ,
>IN ! ?resolves
does>
make-code
;
\ in-xassembler
\ meta also
\ Coded labels without header in target
: label ( -- )
\ @TODO: à surveiller, semble fonctionner
forced
>IN @ Xassembler definitions
here-t constant \ create label in Xassembler vocabulary
>IN ! ?resolves unforced
;
\ definition of word in binary in target
: code ( comp: -- <name> | exec: --)
\ break" code : "
\ @TODO: to debug
target-create
Xassembler also
\ !csp
;
Xassembler also definitions
\ end of binary in target
: end-code
in-meta
\ ?csp \ teste si pile modifiée
;
\ alias for end-code
: c;
end-code
;
meta in-meta
\ affiche nom d'une référence target à partir de son cfa cible
\ variable CFA-REF
\ : .REF ( cfa --- )
\ CFA-REF !
\ target CONTEXT @ HERE #THREADS 2* CMOVE
\ begin
\ HERE #THREADS LARGEST dup
\ while
\ dup NAME> >body 2 + @ CFA-REF @ =
\ if
\ .ID
\ \ else
\ \ drop
\ then
\ @ swap ! STOP?
\ if
\ EXIT
\ then
\ repeat
\ 2DROP in-meta ;
: recreate ( -- )
>IN @ target-create >IN !
;
meta in-meta
\ Compilation des mots de transition
\ original code
\ : T: (S -- )
\ SWITCH TRANSITION DEFINITIONS
\ CREATE
\ SWITCH ]
\ DOES>
\ >R
\ ;
\ Compiling Transition Words
\ : T: ( -- )
\ contextCurrentSave
\ transition definitions
\ create
\ contextCurrentRestore ]
\ does>
\ >r
\ ;
\ Compiling Transition Words
: T: ( -- <name> )
contextCurrentSave
transition definitions
:
contextCurrentRestore
;
\ original code
\ : T; (S -- )
\ SWITCH TRANSITION DEFINITIONS
\ [COMPILE] ; SWITCH
\ ; IMMEDIATE
: T; ( -- )
\ break" T; : " cr
contextCurrentSave
[forth]
[compile] ;
contextCurrentRestore
; immediate
\ : DIGIT? ( CHAR -- F )
\ BASE @ DIGIT NIP
\ ;
\ : PUNCT? ( CHAR -- F )
\ ASCII . over = SWAP
\ ASCII - over = SWAP
\ ASCII / over = SWAP
\ drop OR OR
\ ;
\ : NUMERIC? ( ADDR LEN -- F )
\ dup 1 =
\ if
\ drop c@ DIGIT? EXIT
\ then
\ 1 -ROT 0
\ ?do
\ dup c@ dup DIGIT? swap PUNCT? OR
\ rot AND swap 1+
\ loop
\ drop
\ ;
\ Transition words
T: (
[compile] (
T;
T: \
[compile] \
T;
T: ?\
postpone ?\
T;
T: FRENCH
[compile] FRENCH
T;
T: ENGLISH
[compile] ENGLISH
T;
T: GERMAN
[compile] GERMAN
T;
: ]]
]
;
: [[
\ [compile] [
postpone [
; forth immediate meta
\ \ T: EOF
\ \ [compile] EOF
\ \ T;
\ forward: definitions
\ forward: [
\ : STRING,-T ( -- )
\ ASCII " PARSE dup c,-t string,-t ALIGN
\ ;
\ forward: (.")
\ T: ."
\ [forward] (.") STRING,-T
\ T;
\ forward: (")
\ T: "
\ [forward] (") STRING,-T
\ T;
\ forward: (abort")
\ T: abort"
\ [forward] (abort") STRING,-T
\ T;
\ forward: (LIT)
\ T: LITERAL ( n -- )
\ [forward] (LIT) ,-t
\ T;
\ T: DLITERAL ( d -- )
\ [forward] (LIT) ,-t
\ [forward] (LIT) ,-t
\ T;
\ T: ASCII ( -- )
\ [compile] ASCII [[ transition ]] LITERAL [META]
\ T;
\ \ Mots de définition
\ forward: DOCREATE
\ : create
\ recreate
\ [forward]
\ DOCREATE
\ ?here-t
\ CONSTANT
\ ;
\ : variable ( -- )
\ create
\ 0 ,-t
\ ;
\ : 2variable ( -- )
\ create
\ 0 ,-t 0 ,-t
\ ;
\ forward: DODEFER
\ : DEFER ( -- )
\ target-create [forward] DODEFER 0 ,-t
\ ;
\ forward: DOCONSTANT
\
\ : CONSTANT ( n -- )
\ recreate [forward] DOCONSTANT dup ,-t CONSTANT
\ ;
\ forward: DO2CONSTANT
\ : 2CONSTANT ( d -- )
\ recreate [forward] DO2CONSTANT
\ over over ,-t ,-t 2CONSTANT
\ ;
\ forward: DOSTRING
\ : STRING ( n --)
\ recreate [forward] DOSTRING
\ dup c,-t 0 c,-t dup allot-t STRING
\ ;
\ forth
\ variable #USER-T
\ meta also Xuser definitions
\ : allot ( n -- )
\ #USER-T +!
\ ;
\ forward: DOUSER-VARIABLE
\ : variable ( -- )
\ switch recreate [forward] DOUSER-VARIABLE #USER-T @
\ dup ,-t 2 ALLOT meta definitions
\ [FORTH] CONSTANT [META] switch
\ ;
\ forward: DOUSER-DEFER
\
\ : DEFER ( -- )
\ switch recreate [forward] DOUSER-DEFER #USER-T @
\ dup ,-t 2 ALLOT meta definitions
\ [FORTH] CONSTANT [META] switch
\ ;
meta in-meta
\ Transition words and vocabularies
\ forth variable VOC-LINK-T meta
\ forward: <vocabulary>
\ : vocabulary ( -- )
\ recreate [forward] <vocabulary> here-t #THREADS 0
\ DO
\ 0 ,-t
\ loop
\ here-t VOC-LINK-T @ ,-t VOC-LINK-T !
\ [FORTH] CONSTANT
\ does>
\ @ [META] CONTEXT-T !
\ ;
\ forward: (;USES)
\ forth variable STATE-T meta
\ T: ;USES ( -- )
\ [forward] (;USES) IN-meta Xassembler
\ !csp STATE-T off
\ T;
\ T: [compile]
\ tickT EXECUTE
\ T;
\ forward: (IS)
\ T: IS
\ [forward] (IS)
\ T;
\ : IS
\ tickT >body dup 2+ @
\ if
\ @ >body !-t
\ else
\ 2DROP
\ then
\ ;
\ T: ALIGN
\ T;
\ T: EVEN
\ T;
\ forward: (;CODE)
\ forward: DODOES
\ T: does> ( <forward-type> -- )
\ [forward] (;CODE) ?resolves ( DOES-OP ) 232 c,-t
\ [forward] DODOES here-t dup 2- @-t over - swap 2- !-t
\ T;
\ : NUMERIC ( -- )
\ [FORTH] HERE [META] NUMBER DPL @ 1+
\ if
\ [[ transition ]] DLITERAL [META]
\ else
\ drop [[ transition ]] LITERAL [META]
\ then
\ ;
\ : UNDEFINED ( -- )
\ here-t 0 ,-t in-forward [FORTH]
\ create
\ [META] transition [FORTH] , FALSE , [META]
\ does>
\ forward-code
\ ;
\ *** list of forward references used in core.txt ******************************
\ *** END of list forward in core.txt ******************************
\ Boucle de compilation méta-générateur
\ [FORTH] variable T-IN meta
\ : ] ( -- )
\ STATE-T ON in-transition
\ begin
\ >IN @ T-IN ! defined
\ if
\ EXECUTE
\ else
\ count NUMERIC?
\ if
\ NUMERIC
\ else
\ VALID @
\ if
\ T-IN @ >IN ! UNDEFINED
\ then
\ then
\ then
\ STATE-T @ 0= END? @ OR END? off
\ UNTIL
\ ;
\ : NEWSTATE
\ STATE-T @
\ if
\ ]
\ then
\ STATE
\ ;
\ [FORTH] ' NEWSTATE IS RUN meta
\ T: [ ( -- )
\ in-meta STATE-T off
\ T;
forward: UNNEST
\ T: ; ( -- )
\ [forward] UNNEST [[ transition ]] [
\ T;
forward: NEST
\ \ Structures de contrôle de META
\ : ?>MARK ( -- f addr )
\ true here-t 0 ,-t
\ ;
\ : ?>RESOLVE ( f addr -- )
\ here-t swap !-t ?CONDITION
\ ;
\ : ?<MARK ( -- f addr )
\ true here-t
\ ;
\ : ?<RESOLVE ( f addr -- )
\ ,-t ?CONDITION
\ ;
\ forward: BRANCH
\ forward: ?BRANCH
\ T: begin
\ ?<MARK
\ T;
\ T: AGAIN
\ [forward] BRANCH ?<RESOLVE
\ T;
\ T: UNTIL
\ [forward] ?BRANCH ?<RESOLVE
\ T;
\ T: if
\ [forward] ?BRANCH ?>MARK
\ T;
\ T: then