+: \ IMMEDIATE
+ #TIB @ >IN !
+; \ We can now comment!
+
+\ BASIC DEFINITIONS ----------------------------------------------------------------------
+
: / /MOD SWAP DROP ;
: MOD /MOD DROP ;
: */ -ROT * SWAP / ;
: FALSE 0 ;
: NOT 0= ;
-: CELLS ; \ Allow for slightly more portable code
+\ Translate a number of cells into memory units
+\ (in our case 1 cell = 1 memory unit)
+: CELLS ;
+
+\ Since the smallest unit of memory in our system is 64 bits and since strings
+\ are stored as arrays of 64 bit integers, the character store/fetch words are
+\ just aliases of the standard store/fetch words.
+: C! ! ;
+: C@ @ ;
+: C, , ;
-: DEPTH PSP@ PSP0 @ - ;
+: DEPTH PSP@ PSP0 - ;
: '\n' 10 ;
: BL 32 ;
: LITERAL IMMEDIATE ['] LIT , , ;
-: ':' [ CHAR : ] LITERAL ;
-: ';' [ CHAR ; ] LITERAL ;
-: '(' [ CHAR ( ] LITERAL ;
-: ')' [ CHAR ) ] LITERAL ;
-: '<' [ CHAR < ] LITERAL ;
-: '>' [ CHAR > ] LITERAL ;
-: '"' [ CHAR " ] LITERAL ;
-: 'A' [ CHAR A ] LITERAL ;
-: '0' [ CHAR 0 ] LITERAL ;
-: '-' [ CHAR - ] LITERAL ;
-: '.' [ CHAR . ] LITERAL ;
+: ' BL WORD FIND >CFA ;
+
+: CHAR BL WORD 1+ @ ;
+: [CHAR] IMMEDIATE
+ CHAR
+ ['] LIT , ,
+;
: CR '\n' emit ;
: SPACE BL emit ;
: [COMPILE] IMMEDIATE
- WORD \ get the next word
+ BL WORD \ get the next word
FIND \ find it in the dictionary
>CFA \ get its codeword
, \ and compile that
, \ compile it
;
-: DEBUGON TRUE DEBUG ! ;
-: DEBUGOFF FALSE DEBUG ! ;
-
\ CONTROL STRUCTURES ----------------------------------------------------------------------
: IF IMMEDIATE
['] 0BRANCH , \ compile 0BRANCH
- HERE @ \ save location of the offset on the stack
+ HERE \ save location of the offset on the stack
0 , \ compile a dummy offset
;
: THEN IMMEDIATE
DUP
- HERE @ SWAP - \ calculate the offset from the address saved on the stack
+ HERE SWAP - \ calculate the offset from the address saved on the stack
SWAP ! \ store the offset in the back-filled location
;
: ELSE IMMEDIATE
['] BRANCH , \ definite branch to just over the false-part
- HERE @ \ save location of the offset on the stack
+ HERE \ save location of the offset on the stack
0 , \ compile a dummy offset
SWAP \ now back-fill the original (IF) offset
DUP \ same as for THEN word above
- HERE @ SWAP -
+ HERE SWAP -
SWAP !
;
: BEGIN IMMEDIATE
- HERE @ \ save location on the stack
+ HERE \ save location on the stack
;
: UNTIL IMMEDIATE
['] 0BRANCH , \ compile 0BRANCH
- HERE @ - \ calculate the offset from the address saved on the stack
+ HERE - \ calculate the offset from the address saved on the stack
, \ compile the offset here
;
: AGAIN IMMEDIATE
['] BRANCH , \ compile BRANCH
- HERE @ - \ calculate the offset back
+ HERE - \ calculate the offset back
, \ compile the offset here
;
: WHILE IMMEDIATE
['] 0BRANCH , \ compile 0BRANCH
- HERE @ \ save location of the offset2 on the stack
+ HERE \ save location of the offset2 on the stack
0 , \ compile a dummy offset2
;
: REPEAT IMMEDIATE
['] BRANCH , \ compile BRANCH
SWAP \ get the original offset (from BEGIN)
- HERE @ - , \ and compile it after BRANCH
+ HERE - , \ and compile it after BRANCH
DUP
- HERE @ SWAP - \ calculate the offset2
+ HERE SWAP - \ calculate the offset2
SWAP ! \ and back-fill it in the original location
;
: DO IMMEDIATE
['] LIT , -1 , [COMPILE] IF
['] >R , ['] >R ,
- ['] LIT , HERE @ 0 , ['] >R ,
- HERE @
+ ['] LIT , HERE 0 , ['] >R ,
+ HERE
;
: ?DO IMMEDIATE
['] 2DUP , ['] - , [COMPILE] IF
['] >R , ['] >R ,
- ['] LIT , HERE @ 0 , ['] >R ,
- HERE @
+ ['] LIT , HERE 0 , ['] >R ,
+ HERE
;
: I RSP@ 3 - @ ;
: ?LEAVE IMMEDIATE
['] 0BRANCH , 13 ,
['] R> , ['] RDROP , ['] RDROP ,
- ['] LIT , HERE @ 7 + , ['] DUP , ['] -ROT , ['] - , ['] SWAP , ['] ! ,
+ ['] LIT , HERE 7 + , ['] DUP , ['] -ROT , ['] - , ['] SWAP , ['] ! ,
['] BRANCH ,
0 ,
;
;
: +LOOP IMMEDIATE
+
['] DUP , \ Store copy of increment
['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] + , ['] 2DUP , ['] - ,
[COMPILE] THEN
\ Branch back to begining of loop kernel
- ['] 0BRANCH , HERE @ - ,
+ ['] 0BRANCH , HERE - ,
\ Clean up
['] RDROP , ['] RDROP , ['] RDROP ,
\ Record address of loop end for any LEAVEs to use
- HERE @ SWAP !
+ HERE SWAP !
[COMPILE] ELSE
['] 2DROP , \ Clean up if loop was entirely skipped (?DO)
: ( IMMEDIATE
1 \ allowed nested parens by keeping track of depth
BEGIN
- KEY \ read next character
- DUP '(' = IF \ open paren?
+ >IN @ #TIB @ >= IF \ End of TIB?
+ QUERY \ Get next line
+ THEN
+
+ TIB >IN @ + @ 1 >IN +!
+ DUP [CHAR] ( = IF \ open paren?
DROP \ drop the open paren
1+ \ depth increases
ELSE
- ')' = IF \ close paren?
+ [CHAR] ) = IF \ close paren?
1- \ depth decreases
THEN
THEN
( print the remainder )
DUP 10 < IF
- '0' ( decimal digits 0..9 )
+ [CHAR] 0 ( decimal digits 0..9 )
ELSE
10 - ( hex and beyond digits A..Z )
- 'A'
+ [CHAR] A
THEN
+
EMIT
SWAP ( u flag )
IF ( was it negative? print the - character )
- '-' EMIT
+ [CHAR] - EMIT
THEN
U.
: . 0 .R SPACE ;
: .S ( -- )
- '<' EMIT DEPTH U. '>' EMIT SPACE
- PSP0 @ 1+
+ [CHAR] < EMIT DEPTH U. [CHAR] > EMIT SPACE
+ PSP0 1+
BEGIN
DUP PSP@ 2 - <=
WHILE
( STRINGS ---------------------------------------------------------------------- )
-( Since the smallest unit of memory in our system is 64 bits and since strings
- are stored as arrays of 64 bit integers, the character store/fetch words are
- just aliases of the standard store/fetch words. )
-: C! ! ;
-: C@ @ ;
( Block copy, however, is important and novel: )
: CMOVE ( src dest length -- )
( C, appends a byte to the current compiled word. )
: C,
- HERE @ C!
- 1 HERE +!
+ HERE C!
+ 1 H +!
;
: S" IMMEDIATE ( -- addr len )
STATE @ IF ( compiling? )
['] LITSTRING , ( compile LITSTRING )
- HERE @ ( save the address of the length word on the stack )
+ HERE ( save the address of the length word on the stack )
0 , ( dummy length - we don't know what it is yet )
- KEY DROP
+
BEGIN
- KEY ( get next character of the string )
- DUP '"' <>
+ >IN @ #TIB @ >= IF \ End of TIB?
+ QUERY \ Get next line
+ THEN
+
+ TIB >IN @ + @ 1 >IN +! \ Get char from TIB
+
+ DUP [CHAR] " <>
WHILE
C, ( copy character )
REPEAT
DROP ( drop the double quote character at the end )
DUP ( get the saved address of the length word )
- HERE @ SWAP - ( calculate the length )
+ HERE SWAP - ( calculate the length )
1- ( subtract 1 (because we measured from the start of the length word) )
SWAP ! ( and back-fill the length location )
ELSE ( immediate mode )
- HERE @ ( get the start address of the temporary space )
- KEY DROP
+ HERE ( get the start address of the temporary space )
+
BEGIN
- KEY
- DUP '"' <>
+ >IN @ #TIB @ >= IF \ End of TIB?
+ QUERY \ Get next line
+ THEN
+
+ TIB >IN @ + @ 1 >IN +! \ Get char from TIB
+
+ DUP [CHAR] " <>
WHILE
OVER C! ( save next character )
1+ ( increment address )
REPEAT
DROP ( drop the final " character )
- HERE @ - ( calculate the length )
- HERE @ ( push the start address )
+ HERE - ( calculate the length )
+ HERE ( push the start address )
SWAP ( addr len )
THEN
;
: ." IMMEDIATE ( -- )
- STATE @ IF ( compiling? )
- [COMPILE] S" ( read the string, and compile LITSTRING, etc. )
- ['] TELL , ( compile the final TELL )
- ELSE
- ( In immediate mode, just read characters and print them until we get
- to the ending double quote. )
- KEY DROP
- BEGIN
- KEY
- DUP '"' = IF
- DROP ( drop the double quote character )
- EXIT ( return from this function )
- THEN
- EMIT
- AGAIN
- THEN
+ [COMPILE] S" ( read the string, and compile LITSTRING, etc. )
+ ['] TYPE , ( compile the final TYPE )
;
+: .(
+ BEGIN
+ >IN @ #TIB @ >= IF \ End of TIB?
+ QUERY \ Get next line
+ THEN
+
+ TIB >IN @ + @ 1 >IN +! \ Get char from TIB
+
+ DUP [CHAR] ) = IF
+ DROP ( drop the double quote character )
+ EXIT ( return from this function )
+ THEN
+ EMIT
+ AGAIN
+;
+
+( Converts address of counted string into address of
+ start of string and length of string. )
+: COUNT ( addr1 -- addr2 n )
+ DUP 1+ SWAP @ ;
+
( CONSTANTS AND VARIABLES ------------------------------------------------------ )
: CONSTANT
- WORD HEADER ( make dictionary entry (the name follows CONSTANT) )
- DOCOL , ( append DOCOL (the codeword field of this word) )
- ['] LIT , ( append the codeword LIT )
- , ( append the value on the top of the stack )
- ['] EXIT , ( append the codeword EXIT )
+ CREATE ,
+DOES> @
;
-: ALLOT ( n -- addr )
- HERE @ SWAP ( here n )
- HERE +! ( adds n to HERE, after this the old value of HERE is still on the stack )
+: ALLOT ( n -- )
+ H +! ( adds n to H, after this the old value of H is still on the stack )
;
: VARIABLE
+ CREATE
1 CELLS ALLOT ( allocate 1 cell of memory, push the pointer to this memory )
- WORD HEADER ( make the dictionary entry (the name follows VARIABLE) )
- DOCOL , ( append DOCOL (the codeword field of this word) )
- ['] LIT , ( append the codeword LIT )
- , ( append the pointer to the new memory )
- ['] EXIT , ( append the codeword EXIT )
;
-
: VALUE ( n -- )
- WORD HEADER ( make the dictionary entry (the name follows VALUE) )
- DOCOL , ( append DOCOL )
- ['] LIT , ( append the codeword LIT )
- , ( append the initial value )
- ['] EXIT , ( append the codeword EXIT )
+ CREATE ,
+DOES> @
;
: TO IMMEDIATE ( n -- )
- WORD ( get the name of the value )
+ BL WORD ( get the name of the value )
FIND ( look it up in the dictionary )
- >DFA ( get a pointer to the first data field (the 'LIT') )
- 1+ ( increment to point at the value )
+ >PFA ( 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
- WORD ( get the name of the value )
+ BL WORD ( get the name of the value )
FIND ( look it up in the dictionary )
- >DFA ( get a pointer to the first data field (the 'LIT') )
- 1+ ( increment to point at the value )
+ >PFA ( get a pointer to the first data field (the 'LIT') )
STATE @ IF ( compiling? )
['] LIT , ( compile LIT )
, ( compile the address of the value )
THEN
;
+( Fill u ints, starting at a, with the value b )
+: FILL ( a u b -- )
+ -ROT OVER + SWAP ?DO
+ DUP I !
+ LOOP
+ DROP
+;
+
+: ERASE ( a u -- )
+ 0 FILL
+;
( PRINTING THE DICTIONARY ------------------------------------------------------ )
( FORGET ---------------------------------------------------------------------- )
: FORGET
- WORD FIND ( find the word, gets the dictionary entry address )
+ BL WORD FIND ( find the word, gets the dictionary entry address )
DUP @ LATEST ! ( set LATEST to point to the previous word )
- HERE ! ( and store HERE with the dictionary address )
+ H ! ( and store H with the dictionary address )
;
( DUMP ------------------------------------------------------------------------ )
;
: SEE
- WORD FIND ( find the dictionary entry to decompile )
+ BL WORD DUP FIND ( find the dictionary entry to decompile )
+
+ ?DUP 0= IF
+ ." Word '" COUNT TYPE ." ' not found in dictionary."
+ EXIT
+ THEN
+
+ SWAP DROP
( 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). )
- HERE @ ( address of the end of the last compiled word )
+ HERE ( address of the end of the last compiled word )
LATEST @ ( word last curr )
BEGIN
2 PICK ( word last curr word )
DUP >CFA @ CASE
DOCOL OF
\ Colon definition
- ':' EMIT SPACE DUP ID. SPACE
+ [CHAR] : EMIT SPACE DUP ID. SPACE
DUP ?IMMEDIATE IF ." IMMEDIATE " THEN CR
ENDOF
DOVAR OF
ENDCASE
( begin the definition with : NAME [IMMEDIATE] )
- ( ':' EMIT SPACE DUP ID. SPACE
+ ( [CHAR] : EMIT SPACE DUP ID. SPACE
DUP ?IMMEDIATE IF ." IMMEDIATE " THEN CR 4 )
4 SPACES
- >DFA ( get the data address, ie. points after DOCOL | end-of-word start-of-data )
+ >PFA ( get the data address, ie. points after DOCOL | end-of-word start-of-data )
( now we start decompiling until we hit the end of the word )
BEGIN ( end start )
. ( and print it )
ENDOF
['] LITSTRING OF ( is it LITSTRING ? )
- [ CHAR S ] LITERAL EMIT '"' EMIT SPACE ( print S"<space> )
+ [CHAR] S EMIT [CHAR] " EMIT SPACE ( print S"<space> )
1+ DUP @ ( get the length word )
SWAP 1+ SWAP ( end start+1 length )
- 2DUP TELL ( print the string )
- '"' EMIT SPACE ( finish the string with a final quote )
+ 2DUP TYPE ( print the string )
+ [CHAR] " EMIT SPACE ( finish the string with a final quote )
+ ( end start+1+len, aligned )
1- ( because we're about to add 4 below )
ENDOF
1+ ( end start+1 )
REPEAT
- ';' EMIT CR
+ [CHAR] ; EMIT CR
2DROP ( restore stack )
;
( MEMORY ------------------------------------------------------------------ )
: UNUSED ( -- cells )
- MEMSIZE HERE @ - ;
+ MEMSIZE HERE - ;
The Lambda Lab / projects / forth.jl.git / blobdiff