# Word creation functions
-F_IMMED = 128
-F_HIDDEN = 256
-F_LENMASK = 127
+F_LENMASK = 31
+F_IMMED = 32
+F_HIDDEN = 64
+NFA_MARK = 128
function createHeader(name::AbstractString, flags::Int64)
mem[mem[H]] = mem[LATEST]
mem[LATEST] = mem[H]
mem[H] += 1
- mem[mem[H]] = length(name) | flags; mem[H] += 1
+ mem[mem[H]] = length(name) | flags | NFA_MARK; mem[H] += 1
putString(name, mem[H]); mem[H] += length(name)
end
F_IMMED_CFA = defConst("F_IMMED", F_IMMED)
F_HIDDEN_CFA = defConst("F_HIDDEN", F_HIDDEN)
F_LENMASK_CFA = defConst("F_LENMASK", F_LENMASK)
+NFA_MARK_CFA = defConst("NFA_MARK", NFA_MARK)
# Basic forth primitives
word = lowercase(getString(wordAddr, wordLen))
latest = LATEST
+ lenAndFlags = 0
i = 0
while (latest = mem[latest]) > 0
pushPS(0)
end
-
return NEXT
end)
DUP, FETCH, ZE, ZBRANCH, 3,
DROP, EXIT, # Exit if TIB is exhausted
- STATE_CFA, FETCH, ZBRANCH, 31,
+ STATE_CFA, FETCH, ZBRANCH, 24,
# Compiling
- DUP, FIND, QDUP, ZBRANCH, 19,
+ FIND, QDUP, ZBRANCH, 13,
# Found word.
- SWAP, DROP,
- DUP, TOCFA, SWAP, INCR, FETCH, LIT, F_IMMED, AND, ZBRANCH, 4,
+ LIT, -1, EQ, INVERT, ZBRANCH, 4,
+
# Immediate: Execute!
- EXECUTE, BRANCH, -33,
+ EXECUTE, BRANCH, -26,
# Not immediate: Compile!
- COMMA, BRANCH, -36,
+ COMMA, BRANCH, -29,
# No word found, parse number
- NUMBER, BTICK, LIT, COMMA, COMMA, BRANCH, -43,
+ NUMBER, BTICK, LIT, COMMA, COMMA, BRANCH, -36,
# Interpreting
- DUP, FIND, QDUP, ZBRANCH, 7,
+ FIND, QDUP, ZBRANCH, 5,
# Found word. Execute!
- SWAP, DROP, TOCFA, EXECUTE, BRANCH, -54,
+ DROP, EXECUTE, BRANCH, -44,
# No word found, parse number and leave on stack
- NUMBER, BRANCH, -57,
+ NUMBER, BRANCH, -47,
EXIT]
)
end, flags=F_IMMED)
HIDDEN = defPrimWord("HIDDEN", () -> begin
- addr = popPS() + 1
- mem[addr] = mem[addr] $ F_HIDDEN
+ lenAndFlagsAddr = mem[LATEST] + 1
+ mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_HIDDEN
return NEXT
end)
-HIDE = defWord("HIDE",
- [LIT, 32, WORD,
- FIND,
- HIDDEN,
- EXIT])
-
COLON = defWord(":",
[LIT, 32, WORD,
HEADER,
LIT, DOCOL, COMMA,
- LATEST_CFA, FETCH, HIDDEN,
+ HIDDEN,
RBRAC,
EXIT])
SEMICOLON = defWord(";",
[LIT, EXIT, COMMA,
- LATEST_CFA, FETCH, HIDDEN,
+ HIDDEN,
LBRAC,
EXIT], flags=F_IMMED)
: LITERAL IMMEDIATE ['] LIT , , ;
-: ' BL WORD FIND >CFA ;
+: ' BL WORD FIND DROP ;
: CHAR BL WORD 1+ @ ;
: [CHAR] IMMEDIATE
: [COMPILE] IMMEDIATE
BL WORD \ get the next word
- FIND \ find it in the dictionary
- >CFA \ get its codeword
+ FIND DROP \ find it in the dictionary
, \ and compile that
;
: TO IMMEDIATE ( n -- )
BL WORD ( get the name of the value )
- FIND ( look it up in the dictionary )
- >CFA >BODY ( get a pointer to the first data field (the 'LIT') )
+ FIND DROP ( look it up in the dictionary )
+ >BODY ( get a pointer to the first data field (the 'LIT') )
STATE @ IF ( compiling? )
['] LIT , ( compile LIT )
, ( compile the address of the value )
( x +TO VAL adds x to VAL )
: +TO IMMEDIATE
BL WORD ( get the name of the value )
- FIND ( look it up in the dictionary )
- >CFA >BODY ( get a pointer to the first data field (the 'LIT') )
+ FIND DROP ( look it up in the dictionary )
+ >BODY ( get a pointer to the first data field (the 'LIT') )
STATE @ IF ( compiling? )
['] LIT , ( compile LIT )
, ( compile the address of the value )
( PRINTING THE DICTIONARY ------------------------------------------------------ )
-: ID.
- 1+ ( skip over the link pointer )
+: .NAME
DUP @ ( get the flags/length byte )
F_LENMASK AND ( mask out the flags - just want the length )
?DUP ( while link pointer is not null )
WHILE
DUP ?HIDDEN NOT IF ( ignore hidden words )
- DUP ID. ( but if not hidden, print the word )
+ DUP 1+ .NAME ( but if not hidden, print the word )
SPACE
THEN
@ ( dereference the link pointer - go to previous word )
CR
;
-
-( FORGET ---------------------------------------------------------------------- )
-
-: FORGET
- BL WORD FIND ( find the word, gets the dictionary entry address )
- DUP @ LATEST ! ( set LATEST to point to the previous word )
- H ! ( and store H with the dictionary address )
-;
-
( DUMP ------------------------------------------------------------------------ )
\ TODO!
( DECOMPILER ------------------------------------------------------------------ )
-: CFA>
- LATEST @ ( start at LATEST dictionary entry )
+: >NAME
BEGIN
- ?DUP ( while link pointer is not null )
- WHILE
- 2DUP SWAP ( cfa curr curr cfa )
- < IF ( current dictionary entry < cfa? )
- NIP ( leave curr dictionary entry on the stack )
- EXIT
- THEN
- @ ( follow link pointer back )
- REPEAT
- DROP ( restore stack )
- 0 ( sorry, nothing found )
+ 1- DUP @
+ NFA_MARK AND
+ NFA_MARK = UNTIL
;
+: >LFA >NAME 1- ;
+
: SEE
- BL WORD DUP FIND ( find the dictionary entry to decompile )
+ BL WORD FIND ( find the dictionary entry to decompile )
- ?DUP 0= IF
+ 0= IF
." Word '" COUNT TYPE ." ' not found in dictionary."
EXIT
THEN
- SWAP DROP
+ >LFA
( Now we search again, looking for the next word in the dictionary. This gives us
the length of the word that we will be decompiling. (Well, mostly it does). )
DUP >CFA @ CASE
DOCOL OF
\ Colon definition
- [CHAR] : EMIT SPACE DUP ID. SPACE
+ [CHAR] : EMIT SPACE DUP 1+ .NAME SPACE
DUP ?IMMEDIATE IF ." IMMEDIATE " THEN CR
ENDOF
DOVAR OF
\ Variable definition
- ." Variable " DUP ID. CR
+ ." Variable " DUP 1+ .NAME CR
2DROP EXIT
ENDOF
DOCON OF
\ Constant definition
- ." Constant " DUP ID. CR
+ ." Constant " DUP 1+ .NAME CR
2DROP EXIT
ENDOF
DROP 2DROP EXIT
ENDCASE
- ( begin the definition with : NAME [IMMEDIATE] )
- ( [CHAR] : EMIT SPACE DUP ID. SPACE
- DUP ?IMMEDIATE IF ." IMMEDIATE " THEN CR 4 )
-
4 SPACES
>CFA >BODY ( get the data address, ie. points after DOCOL | end-of-word start-of-data )
['] ['] OF ( is it ['] ? )
." ['] "
1+ DUP @ ( get the next codeword )
- CFA> ( and force it to be printed as a dictionary entry )
- ID. SPACE
+ >NAME ( and force it to be printed as a dictionary entry )
+ .NAME SPACE
ENDOF
['] EXIT OF ( is it EXIT? )
( We expect the last word to be EXIT, and if it is then we don't print it
ENDOF
( default case: )
DUP ( in the default case we always need to DUP before using )
- CFA> ( look up the codeword to get the dictionary entry )
- ID. SPACE ( and print it )
+ >NAME ( look up the codeword to get the dictionary entry )
+ .NAME SPACE ( and print it )
ENDCASE
1+ ( end start+1 )
;
+( FORGET and HIDE ------------------------------------------------------------ )
+
+: FORGET
+ BL WORD FIND >LFA ( find the word, gets the dictionary entry address )
+ DUP @ LATEST ! ( set LATEST to point to the previous word )
+ H ! ( and store H with the dictionary address )
+;
+
+: HIDE
+ BL WORD FIND DROP >NAME
+ DUP F_HIDDEN OR SWAP !
+;
+
( MEMORY ------------------------------------------------------------------ )
: UNUSED ( -- cells )
The Lambda Lab / projects / forth.jl.git / commitdiff