/
embed.fth
1370 lines (1312 loc) · 57.3 KB
/
embed.fth
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system +order 0 <ok> !
.( FORTH META COMPILATION START ) cr
\ ============================================================================
\ # The Meta-Compiler
\
only forth definitions hex
system +order 0 <ok> !
variable meta ( Metacompilation vocabulary )
meta +order definitions
variable assembler.1 ( Target assembler vocabulary )
variable target.1 ( Target dictionary )
variable tcp ( Target dictionary pointer )
variable tlast ( Last defined word in target )
variable tdoVar ( Location of doVar in target )
variable tdoConst ( Location of doConst in target )
variable tdoNext ( Location of doNext in target )
variable tdoPrintString ( Location of .string in target )
variable tdoStringLit ( Location of string-literal in target )
variable fence ( Do not peephole optimize before this point )
5000 constant #target ( Location where target image will be built )
2 constant =cell ( Target cell size )
$3A00 constant pad-area ( area for pad storage )
( 1 constant verbose ( verbosity level, higher is more verbose )
#target 2000 0 fill ( Erase the target memory location )
: ]asm assembler.1 +order ; immediate ( -- )
: a: current @ assembler.1 current ! : ; ( "name" -- wid link )
: a; [compile] ; current ! ; immediate ( wid link -- )
: ( [char] ) parse 2drop ; immediate ( "comment" -- discard until parenthesis )
: \ source drop @ >in ! ; immediate ( "comment" -- discard until end of line )
: there tcp @ ; ( -- a : target dictionary pointer value )
: tc! #target + c! ; ( u a -- : store character in target )
: tc@ #target + c@ ; ( a -- u : retrieve character in target )
: [last] tlast @ ; ( -- a : last defined word in target )
: t! over $FF and over tc! swap 8 rshift swap 1+ tc! ; ( u a -- )
: t@ dup tc@ swap 1+ tc@ 8 lshift or ; ( a -- u )
: 2/ 1 rshift ; ( u -- u : non-standard definition divide by 2 )
\ : 2* 1 lshift ; ( u -- u : multiple by two, non-standard )
: talign there 1 and tcp +! ; ( -- : align target dictionary pointer value )
: tc, there tc! 1 tcp +! ; ( c -- : write byte into target dictionary )
: t, there t! =cell tcp +! ; ( u -- : write cell into target dictionary )
\ : tallot tcp +! ; ( n -- : allocate memory in target dictionary )
: update-fence there fence ! ; ( -- : update optimizer fence location )
: $literal ( <string>, -- )
[char] " word count dup tc, 1- for count tc, next drop talign update-fence ;
: tcells =cell * ; ( u -- a )
: tbody 1 tcells + ; ( a -- a )
: tcfa cfa ; ( PWD -- CFA )
: tnfa nfa ; ( PWD -- NFA )
: meta! ! ; ( u a -- )
: checksum #target there crc ; ( -- u : calculate CRC of target image )
: finished ( -- : save target image and display statistics )
hex
." COMPLETE" cr
." HOST: " here . cr
." TARGET: " there . cr
only forth definitions hex
." SAVING..." #target #target there + (save) throw ." DONE" cr
." STACK>" .s cr ;
: [a] ( "name" -- : find word and compile an assembler word )
bl word assembler.1 search-wordlist 0= abort" [a]? "
cfa compile, ; immediate
: asm[ assembler.1 -order ; immediate ( -- )
a: #literal $8000 a; ( literal instruction - top bit set )
a: #alu $6000 a; ( ALU instruction, further encoding below... )
a: #call $4000 a; ( function call instruction )
a: #?branch $2000 a; ( branch if zero instruction )
a: #branch $0000 a; ( unconditional branch )
a: #t $0000 a; ( T = t )
a: #n $0100 a; ( T = n )
a: #t+n $0200 a; ( T = t+n )
a: #t&n $0300 a; ( T = t&n )
a: #t|n $0400 a; ( T = t|n )
a: #t^n $0500 a; ( T = t^n )
a: #~t $0600 a; ( T = ~t )
a: #t==n $0700 a; ( T = n == t? )
a: #n<t $0800 a; ( T = n < t, signed version )
a: #n>>t $0900 a; ( T = n right shift by t places )
a: #t-1 $0A00 a; ( T == t - 1 )
a: #r $0B00 a; ( T = Top of Return Stack )
a: #[t] $0C00 a; ( T = memory[t] )
a: #n<<t $0D00 a; ( T = n << t )
a: #sp@ $0E00 a; ( T = depth )
a: #nu<t $0F00 a; ( T = n < t, unsigned )
a: #cpu! $1000 a; ( T = set interrupts )
a: #cpu? $1100 a; ( T = interrupts set? )
a: #rp@ $1200 a; ( T = r-depth )
a: #t==0 $1300 a; ( T = t == 0? )
a: #cpu-id $1400 a; ( T = CPU ID )
\ a: #alu-lit $1500 a; ( T = instruction, hidden )
a: d+1 $0001 or a; ( increment variable stack by one )
a: d-1 $0003 or a; ( decrement variable stack by one )
a: d-2 $0002 or a; ( decrement variable stack by two, not used )
a: r+1 $0004 or a; ( increment variable stack by one )
a: r-1 $000C or a; ( decrement variable stack by one )
a: r-2 $0008 or a; ( decrement variable stack by two, not used )
a: r->pc $0010 or a; ( Set Program Counter to Top of Return Stack )
a: n->[t] $0020 or a; ( Set Next on Variable Stack to Top on Variable Stack )
a: t->r $0040 or a; ( Set Top of Return Stack to Top on Variable Stack )
a: t->n $0080 or a; ( Set Next on Variable Stack to Top on Variable Stack )
: ?set dup $E000 and abort" argument too large" ; ( u -- )
a: branch 2/ ?set [a] #branch or t, a; ( a -- : an Unconditional branch )
a: ?branch 2/ ?set [a] #?branch or t, a; ( a -- : Conditional branch )
a: call 2/ ?set [a] #call or t, a; ( a -- : Function call )
a: ALU ?set [a] #alu or a; ( u -- : Make ALU instruction )
a: alu [a] ALU t, a; ( u -- : ALU operation )
a: literal ( n -- : compile a number into target )
dup [a] #literal and if ( numbers above $7FFF take up two instructions )
invert recurse ( the number is inverted, and 'literal' is called again )
[a] #~t [a] alu ( then an invert instruction is compiled into the target )
else
[a] #literal or t, ( numbers below $8000 are single instructions )
then a;
a: return ( -- : Compile a return into the target )
[a] #t [a] r->pc [a] r-1 [a] alu a;
: previous there =cell - ; ( -- a )
: lookback previous t@ ; ( -- u )
: call? lookback $E000 and [a] #call = ; ( -- t )
: call>goto previous dup t@ $1FFF and swap t! ; ( -- )
: fence? fence @ previous u> ; ( -- t )
: safe? lookback $E000 and [a] #alu = lookback $001C and 0= and ; ( -- t )
: alu>return previous dup t@ [a] r->pc [a] r-1 swap t! ; ( -- )
: exit-optimize ( -- )
fence? if [a] return exit then
call? if call>goto exit then
safe? if alu>return exit then
[a] return ;
: exit, exit-optimize update-fence ; ( -- )
: compile-only tlast @ tnfa t@ $20 or tlast @ tnfa t! ; ( -- )
: immediate tlast @ tnfa t@ $40 or tlast @ tnfa t! ; ( -- )
: mcreate current @ >r target.1 current ! create r> current ! ;
: thead ( b u -- : compile word header into target dictionary )
talign
there [last] t, tlast !
there #target + pack$ c@ 1+ aligned tcp +! talign ;
: lookahead ( -- b u : parse a word, but leave it in the input stream )
>in @ >r bl parse r> >in ! ;
: literal [a] literal ; ( u -- )
: [ ' literal <literal> ! ; ( -- )
: ] ' (literal) <literal> ! ; ( -- )
: h: ( -- : create a word with no name in the target dictionary )
[compile] [
$F00D mcreate there , update-fence does> @ [a] call ;
: t: ( "name", -- : creates a word in the target dictionary )
lookahead thead h: ;
: ?unstructured $F00D xor if source type cr 1 abort" unstructured! " then ;
: fallthrough; [compile] ] ?unstructured ; ( u -- )
: t; fallthrough; exit, ; \ "[a] return" <- unoptimized version
: ;; t; ?unstructured ;
: fetch-xt @ dup 0= abort" (null) " ; ( a -- xt )
: tconstant ( "name", n --, Run Time: -- )
>r
lookahead
thead
there tdoConst fetch-xt [a] call r> t, >r
mcreate r> ,
does> @ tbody t@ [a] literal ;
: tvariable ( "name", n -- , Run Time: -- a )
>r
lookahead
thead
there tdoVar fetch-xt [a] call r> t, >r
mcreate r> ,
does> @ tbody [a] literal ;
: tlocation ( "name", n -- : Reserve space in target for a memory location )
there swap t, mcreate , does> @ [a] literal ;
: [t] ( "name", -- a : get the address of a target word )
bl word target.1 search-wordlist 0= abort" [t]?"
cfa >body @ ;
: [f] ( "name", -- execute word in host Forth vocabulary )
bl word forth-wordlist search-wordlist 0= abort" [f]?"
cfa execute ;
: [v] [t] =cell + ; ( "name", -- a )
: xchange ( "name1", "name2", -- : exchange target vocabularies )
[last] [t] t! [t] t@ tlast meta! ;
: begin there update-fence ; ( -- a )
: until [a] ?branch ; ( a -- )
: if there update-fence 0 [a] ?branch ; ( -- a )
: skip there update-fence 0 [a] branch ; ( -- a )
: then begin 2/ over t@ or swap t! ; ( a -- )
: else skip swap then ; ( a -- a )
: while if swap ; ( a -- a a )
: repeat [a] branch then update-fence ; ( a -- )
: again [a] branch update-fence ; ( a -- )
: aft drop skip begin swap ; ( a -- a )
: constant mcreate , does> @ literal ; ( "name", a -- )
: [char] char literal ; ( "name" )
: postpone [t] [a] call ; ( "name", -- )
: next tdoNext fetch-xt [a] call t, update-fence ; ( a -- )
: exit exit, ; ( -- )
: ' [t] literal ; ( "name", -- )
: recurse tlast @ tcfa [a] call ; ( -- )
: ." tdoPrintString fetch-xt [a] call $literal ; ( "string", -- )
: $" tdoStringLit fetch-xt [a] call $literal ; ( "string", -- )
: nop ]asm #t alu asm[ ;
: dup ]asm #t t->n d+1 alu asm[ ;
: over ]asm #n t->n d+1 alu asm[ ;
: invert ]asm #~t alu asm[ ;
: + ]asm #t+n d-1 alu asm[ ;
: swap ]asm #n t->n alu asm[ ;
: nip ]asm #t d-1 alu asm[ ;
: drop ]asm #n d-1 alu asm[ ;
: >r ]asm #n t->r r+1 d-1 alu asm[ ;
: r> ]asm #r t->n r-1 d+1 alu asm[ ;
: r@ ]asm #r t->n d+1 alu asm[ ;
: @ ]asm #[t] alu asm[ ;
: rshift ]asm #n>>t d-1 alu asm[ ;
: lshift ]asm #n<<t d-1 alu asm[ ;
: = ]asm #t==n d-1 alu asm[ ;
: u< ]asm #nu<t d-1 alu asm[ ;
: < ]asm #n<t d-1 alu asm[ ;
: and ]asm #t&n d-1 alu asm[ ;
: xor ]asm #t^n d-1 alu asm[ ;
: or ]asm #t|n d-1 alu asm[ ;
: sp@ ]asm #sp@ t->n d+1 alu asm[ ;
: 1- ]asm #t-1 alu asm[ ;
: rp@ ]asm #rp@ t->n d+1 alu asm[ ;
: 0= ]asm #t==0 alu asm[ ;
: rdrop ]asm #t r-1 alu asm[ ;
\ : 2rdrop ]asm #t r-2 alu asm[ ;
\ : rdrop>r ]asm #n t->r d-1 alu asm[ ;
: dup>r ]asm #t t->r r+1 alu asm[ ;
: over-and ]asm #t&n alu asm[ ;
: over+ ]asm #t+n alu asm[ ;
\ : over-xor ]asm #t^n alu asm[ ;
: >r-dup ]asm #n t->r r+1 alu asm[ ;
: 2dup= ]asm #t==n t->n d+1 alu asm[ ;
: 2dup< ]asm #n<t t->n d+1 alu asm[ ;
: 2dupu< ]asm #nu<t t->n d+1 alu asm[ ;
: 2dup-xor ]asm #t^n t->n d+1 alu asm[ ;
: store ]asm #n n->[t] d-1 alu asm[ ;
: tuck! ]asm #t n->[t] d-1 alu asm[ ;
: cpu-id ]asm #cpu-id d+1 alu asm[ ;
: cpu! ]asm #cpu! d-1 alu asm[ ;
: cpu? ]asm #cpu? t->n d+1 alu asm[ ;
: dup@ ]asm #[t] t->n d+1 alu asm[ ;
: r>rdrop ]asm #r t->n r-2 d+1 alu asm[ ;
: rxchg ]asm #r t->r alu asm[ ;
: nip-nip ]asm #t d-2 alu asm[ ;
: for >r begin ;
: meta: : ;
( : :noname h: ; )
: : t: ;
meta: ; t; ;
hide meta:
hide t:
hide t;
]asm #~t ALU asm[ constant =invert ( invert instruction )
]asm #t r->pc r-1 ALU asm[ constant =exit ( return/exit instruction )
]asm #n t->r d-1 r+1 ALU asm[ constant =>r ( to r. stk. instruction )
$20 constant =bl ( blank, or space )
$D constant =cr ( carriage return )
$A constant =lf ( line feed )
$8 constant =bs ( back space )
$7F constant =del ( delete key )
\ $1B constant =escape ( escape character )
$50 constant tib-length ( size of terminal input buffer )
$40 constant word-length ( maximum length of a word )
$40 constant c/l ( characters per line in a block )
$10 constant l/b ( lines in a block )
$2BAD constant magic ( magic number for compiler security )
( Volatile variables )
$3B02 constant last-def ( last, possibly unlinked, word definition )
$3B06 constant id ( used for source id )
$3B0A constant handler ( current handler for throw/catch )
$3B0C constant block-dirty ( -1 if loaded block buffer is modified )
$3B14 constant <expect> ( "accept" vector )
$3B16 constant <tap> ( "tap" vector, for terminal handling )
$3B18 constant <echo> ( c -- : emit character )
$3B1A constant context ( holds current context for search order )
( area for context is #vocs large )
$3B2A constant #tib ( Current count of terminal input buffer )
$3B2C constant tib-buf ( ... and address )
$3B2E constant tib-start ( backup tib-buf value )
$3C00 constant block-buffer ( block buffer is stored here )
$10 constant header-length ( location of length in header )
$12 constant header-crc ( location of CRC in header )
$14 constant header-options ( location of options bits in header )
target.1 +order ( Add target word dictionary to search order )
meta -order meta +order ( Reorder so *meta* has a higher priority )
system -order ( Remove system vocabulary to previously accidents )
forth-wordlist -order ( Remove normal Forth words to prevent accidents )
\ ============================================================================
\ # Start of Image
0 t, \ $0: IRQ-0; Reset Vector / maskable IRQ for Down D-PAD button
0 t, \ $2: IRQ-1; UART RX FIFO NOT EMPTY
0 t, \ $4: IRQ-2; UART RX FIFO FULL
0 t, \ $6: IRQ-3; UART TX FIFO NOT EMPTY
0 t, \ $8: IRQ-4; UART TX FIFO FULL
0 t, \ $A: IRQ-5; PS/2 KEYBOARD (NEW CHARACTER)
0 t, \ $C: IRQ-6; TIMER
0 t, \ $E: IRQ-7; D-PAD BUTTON CHANGED
0 t, \ $10: For Length of Forth image, different from VM size
0 t, \ $12: For CRC of Forth image, not entire VM memory
$0001 t, \ $14: Header options
h: doVar r> ; ( -- a : push return address and exit to caller )
h: doConst r> @ ; ( -- u : push value at return address and exit to caller )
[t] doVar tdoVar meta!
[t] doConst tdoConst meta!
0 tlocation root-voc ( root vocabulary )
0 tlocation editor-voc ( editor vocabulary )
pad-area tconstant pad ( pad variable - offset into temporary storage )
$8 constant #vocs ( number of vocabularies in allowed )
$2 tconstant cell ( size of a cell in bytes )
$400 tconstant b/buf ( size of a block )
0 tlocation #irq ( Used in example IRQ, count of IRQs )
0 tlocation cp ( Dictionary Pointer: Set at end of file )
0 tlocation _forth-wordlist ( set at the end near the end of the file )
0 tlocation _system ( system specific vocabulary )
$0 tvariable >in ( Hold character pointer when parsing input )
1 tlocation seed1 ( PRNG seed; never set to zero )
1 tlocation seed2 ( PRNG seed; never set to zero )
$0 tvariable state ( compiler state variable )
$0 tvariable hld ( Pointer into hold area for numeric output )
$A tvariable base ( Current output radix )
$0 tvariable span ( Hold character count received by expect )
0 tvariable blk ( current blk loaded, set in *cold* )
$FFFF tvariable dpl ( number of places after fraction )
0 tvariable current ( WID to add definitions to )
xchange _forth-wordlist _system
0 tvariable <save> ( holds execution vector for saving blocks )
0 tvariable <block> ( holds execution vector for block )
0 tvariable <literal> ( holds execution vector for literal )
0 tvariable <ok> ( prompt execution vector )
0 tvariable <key> ( -- c : new character, blocking input )
0 tvariable <emit> ( c -- : emit character )
( : nop nop ; ( -- : do nothing )
: cpu-id cpu-id ; ( -- u : returns CPU ID )
: cpu? cpu? ; ( -- u : returns CPU status )
: cpu! cpu! ; ( u -- : sets CPU status )
xchange _system _forth-wordlist
: dup dup ; ( n -- n n : duplicate value on top of stack )
: over over ; ( n1 n2 -- n1 n2 n1 : duplicate second value on stack )
: invert invert ; ( u -- u : bitwise invert of value on top of stack )
: + + ; ( u u -- u : addition without carry )
: swap swap ; ( n1 n2 -- n2 n1 : swap two values on stack )
: nip nip ; ( n1 n2 -- n2 : remove second item on stack )
: drop drop ; ( n -- : remove item on stack )
: @ @ ; ( a -- u : load value at address )
: ! store drop ; ( u a -- : store *u* at address *a* )
: rshift rshift ; ( u1 u2 -- u : shift u2 by u1 places to the right )
: lshift lshift ; ( u1 u2 -- u : shift u2 by u1 places to the left )
: = = ; ( u1 u2 -- t : does u2 equal u1? )
: u< u< ; ( u1 u2 -- t : is u2 less than u1 )
: < < ; ( u1 u2 -- t : is u2 less than u1, signed version )
: and and ; ( u u -- u : bitwise and )
: xor xor ; ( u u -- u : bitwise exclusive or )
: or or ; ( u u -- u : bitwise or )
: 1- 1- ; ( u -- u : decrement top of stack )
: 0= 0= ; ( u -- t : if top of stack equal to zero )
: sp@ sp@ ; ( -- u : stack position [equivalent to depth] )
there constant inline-start
( : rp@ rp@ fallthrough; compile-only ( -- u )
: exit exit fallthrough; compile-only ( -- )
: >r >r fallthrough; compile-only ( u --, R: -- u )
: r> r> fallthrough; compile-only ( -- u, R: u -- )
: r@ r@ fallthrough; compile-only ( -- u )
: rdrop rdrop fallthrough; compile-only ( --, R: u -- )
there constant inline-end
\ ============================================================================
\ # Core Words
( 0 tvariable hidden ( vocabulary for hidden words )
h: [-1] -1 ; ( -- -1 : space saving measure, push -1 )
h: 0x8000 $8000 ; ( -- $8000 : space saving measure, push $8000 )
h: 2drop-0 drop fallthrough; ( n n -- 0 )
h: drop-0 drop fallthrough; ( n -- 0 )
h: 0x0000 $0000 ; ( -- $0000 : space/optimization, push $0000 )
h: state@ state @ ; ( -- u )
h: first-bit 1 and ; ( u -- u )
h: in@ >in @ ; ( -- u )
h: base@ base @ ; ( -- u )
h: hld@ hld @ ; ( -- u )
h: blk-@ blk @ ;
h: ?exit if rdrop exit then ; ( u --, R: xt -- xt| : conditional return )
: 2drop drop drop ; ( n n -- )
: 1+ 1 + ; ( n -- n : increment a value )
: negate 1- invert ; ( n -- n : negate a number )
: - negate + ; ( n1 n2 -- n : subtract n1 from n2 )
h: over- over - ; ( u u -- u u )
: aligned dup first-bit + ; ( b -- a )
h: cell- cell - ; ( a -- a : adjust address to previous cell )
: cell+ cell + ; ( a -- a : move address forward to next cell )
: cells 1 lshift ; ( n -- n : convert cells count to address count )
: chars 1 rshift ; ( n -- n : convert bytes to number of cells )
: ?dup dup if dup exit then ; ( n -- 0 | n n : duplicate non zero value )
: > swap < ; ( n1 n2 -- t : signed greater than, n1 > n2 )
: u> swap u< ; ( u1 u2 -- t : unsigned greater than, u1 > u2 )
: <> = invert ; ( n n -- t : not equal )
: 0<> 0= invert ; ( n n -- t : not equal to zero )
: 0> 0 > ; ( n -- t : greater than zero? )
: 0< 0 < ; ( n -- t : less than zero? )
: 2dup over over ; ( n1 n2 -- n1 n2 n1 n2 )
: tuck swap over ; ( n1 n2 -- n2 n1 n2 )
: +! tuck @ + fallthrough; ( n a -- : increment value at *a* by *n* )
h: swap! swap ! ; ( a u -- )
h: zero 0 swap! ; ( a -- : zero value at address )
: 1+! 1 h: s+! swap +! ;; ( a -- : increment value at address by 1 )
: 1-! [-1] s+! ; ( a -- : decrement value at address by 1 )
: 2! ( d a -- ) tuck! cell+ ! ; ( n n a -- )
: 2@ ( a -- d ) dup cell+ @ swap @ ; ( a -- n n )
h: get-current current @ ; ( -- wid )
: bl =bl ; ( -- c )
: within over- >r - r> u< ; ( u lo hi -- t )
h: s>d dup 0< ; ( n -- d )
: abs s>d if negate exit then ; ( n -- u )
: source #tib 2@ ; ( -- a u )
h: tib source drop ; ( -- a )
: source-id id @ ; ( -- 0 | -1 )
: rot >r swap r> swap ; ( n1 n2 n3 -- n2 n3 n1 )
: -rot rot rot ; ( n1 n2 n3 -- n3 n1 n2 )
h: rot-drop rot drop ; ( n1 n2 n3 -- n2 n3 )
h: d0= or 0= ; ( d -- t )
( : 2swap >r -rot r> -rot ; ( n1 n2 n3 n4 -- n3 n4 n1 n2 )
( : d< rot )
( 2dup )
( > if = nip-nip if 0 exit then [-1] exit then 2drop u< ; ( d -- f )
( : d> 2swap d< ; ( d -- t )
( : du> 2swap du< ; ( d -- t )
( : d= rot = -rot = and ; ( d d -- t )
( : d- dnegate d+ ; ( d d -- d )
( : dabs s>d if dnegate exit then ; ( d -- ud )
( : even first-bit 0= ; ( u -- t )
( : odd even 0= ; ( u -- t )
( : pow2? dup dup 1- and 0= and ; ( u -- u|0 : is u a power of 2? )
( : opposite? xor 0< ; ( n n -- f : true if opposite signs )
: execute >r ; ( cfa -- : execute a function )
h: @execute @ ?dup if execute exit then ; ( cfa -- )
: c@ dup@ swap first-bit 3 lshift rshift h: lsb $FF and ;; ( b--c: char load )
: c! ( c b -- : store character at address )
tuck first-bit 3 lshift dup>r swap lsb swap
lshift over @
$FF r> 8 xor lshift and or swap! ;
: here cp @ ; ( -- a )
: align here fallthrough; ( -- )
h: cp! aligned cp ! ; ( n -- )
: allot cp +! ; ( n -- )
h: 2>r rxchg swap >r >r ; ( u1 u2 --, R: -- u1 u2 )
h: 2r> r> r> swap rxchg nop ; ( -- u1 u2, R: u1 u2 -- )
h: doNext 2r> ?dup if 1- >r @ >r exit then cell+ >r ;
[t] doNext tdoNext meta!
: min 2dup< fallthrough; ( n n -- n )
h: mux if drop exit then nip ; ( n1 n2 b -- n : multiplex operation )
: max 2dup > mux ; ( n n -- n )
( : 2over 2>r 2dup 2r> 2swap ; )
( : 2nip 2>r 2drop 2r> nop ; )
( : 4dup 2over 2over ; )
( : dmin 4dup d< if 2drop exit else 2nip ; )
( : dmax 4dup d> if 2drop exit else 2nip ; )
\ : um+ ( w w -- w carry )
\ over over+ >r
\ r@ 0 < invert >r
\ over over-and
\ 0 < r> or >r
\ or 0 < r> and 1- invert
\ r> swap ;
\ h: upivot ( u1 u2 -- min max ) 2dupu< if exit then swap ;
: um+ 2dupu< 0= if swap then over+ swap over swap u< 1 and ; ( u u -- u carry )
h: dnegate invert >r invert 1 um+ r> + ; ( d -- d )
h: d+ >r swap >r um+ r> + r> + ; ( d d -- d )
: um* ( u u -- ud )
0 swap ( u1 0 u2 ) $F
for dup um+ >r >r-dup um+ r> + r>
if >r over um+ r> + then
next rot drop ;
: * um* drop ; ( n n -- n )
h: rp! ( n -- , R: ??? -- ??? : set the return stack pointer )
r> swap begin dup rp@ = 0= while rdrop repeat drop >r ;
: key? <key> @execute ; ( -- c -1 | 0 )
: key begin key? until ; ( -- c )
: /string over min rot over+ -rot - ; ( b u1 u2 -- b u : advance string u2 )
h: +string 1 /string ; ( b u -- b u : )
: count dup 1+ swap c@ ; ( b -- b u )
h: string@ over c@ ; ( b u -- b u c )
xchange _forth-wordlist _system
h: lshift-xor lshift xor ;
h: rshift-xor rshift xor ;
: crc ( b u -- u : calculate ccitt-ffff CRC )
[-1] ( -1 = 0xffff ) >r
begin
?dup
while
string@ r> swap
( CCITT polynomial $1021, or "x16 + x12 + x5 + 1" )
over $8 rshift-xor ( crc x )
dup $4 rshift-xor ( crc x )
dup $5 lshift-xor ( crc x )
dup $C lshift-xor ( crc x )
swap $8 lshift-xor ( crc )
>r +string
repeat r> nip ;
xchange _system _forth-wordlist
h: last get-current @ ; ( -- pwd )
h: echo <echo> @execute ; ( c -- )
: emit <emit> @execute ; ( c -- : write out a char )
: cr =cr emit =lf emit ; ( -- : emit a newline )
: space 1 fallthrough; ( -- : emit a space )
h: spaces =bl fallthrough; ( +n -- )
h: nchars ( +n c -- : emit c n times )
swap 0 max for aft dup emit then next drop ;
h: colon-space [char] : emit space ; ( -- )
\ This version of pick mashes the return stack for large pick depths, an
\ alternative would be to move non-destructively up and down the stack with
\ special instructions.
( vn...v0 u -- vn...v0 vu )
: pick ?dup if swap >r 1- pick r> swap exit then dup ;
h: ndrop for aft drop then next ;
h: >char dup $7F =bl within if drop [char] _ then ; ( c -- c )
: type 0 fallthrough; ( b u -- )
h: typist ( b u f -- : print a string )
>r begin dup while
swap count r@
if
>char
then
emit
swap 1-
repeat
rdrop 2drop ;
h: $type [-1] typist ; ( b u -- )
: cmove for aft >r-dup c@ r@ c! 1+ r> 1+ then next 2drop ; ( b b u -- )
: fill swap for swap aft 2dup c! 1+ then next 2drop ; ( b u c -- )
: catch ( xt -- exception# | 0 : return addr on stack )
sp@ >r ( xt : save data stack depth )
handler @ >r ( xt : and previous handler )
rp@ handler ! ( xt : set current handler )
execute ( execute returns if no throw )
r> handler ! ( restore previous handler )
rdrop ( discard saved stack ptr )
0x0000 ; ( 0 : normal completion )
: throw ( ??? exception# -- ??? exception# )
?dup if ( exc# \ 0 throw is no-op )
handler @ rp! ( exc# : restore prev return stack )
r> handler ! ( exc# : restore prev handler )
rxchg ( saved-sp : exc# on return stack )
sp@ swap - ndrop r> ( exc# : restore stack )
( return to the caller of catch because return )
( stack is restored to the state that existed )
( when catch began execution )
then ;
h: -throw negate throw ; ( u -- : negate and throw )
[t] -throw 2/ 4 tcells t!
: um/mod ( ud u -- ur uq )
?dup 0= if $A -throw exit then
2dupu<
if negate $F
for >r-dup um+ >r >r-dup um+ r> + dup
r> r@ swap >r um+ r> or
if >r drop 1 + r> else drop then r>
next
drop swap exit
then 2drop drop [-1] dup ;
: m/mod ( d n -- r q ) \ floored division
dup 0< dup>r
if
negate >r dnegate r>
then
>r-dup 0< if r@ + then r> um/mod r>
if swap negate swap exit then ;
\ : */ >r um* r> m/mod nip ; ( n n n -- )
: /mod over 0< swap m/mod ; ( n n -- r q )
: mod /mod drop ; ( n n -- r )
: / /mod nip ; ( n n -- q )
h: 1depth 1 fallthrough; ( ??? -- : check depth is at least one )
h: ?depth dup 0= if drop exit then sp@ 1- u> if 4 -throw exit then ; ( u -- )
: decimal $A fallthrough; ( -- : set base to decimal )
h: base! base ! ; ( u -- : set base )
: hex $10 base! ; ( -- )
\ h: radix base@ dup 2 - $23 u< ?exit decimal $28 -throw ; ( -- u )
: hold hld@ 1- dup hld ! c! hld@ pad $80 - u> ?exit $11 -throw ; ( c -- )
h: extract dup>r um/mod rxchg um/mod r> rot ; ( ud ud -- ud u )
h: digit 9 over < 7 and + [char] 0 + ; ( u -- c )
: #> 2drop hld@ pad over- ; ( w -- b u )
: # 2 ?depth 0 base@ extract digit hold ; ( d -- d )
: #s begin # 2dup d0= until ; ( d -- 0 )
: <# pad hld ! ; ( -- )
: sign 0< 0= ?exit [char] - hold ; ( n -- )
h: (.) ( n -- b u : convert a signed integer to a numeric string )
dup>r abs 0 <# #s r> sign #> ;
h: (u.) 0 <# #s #> ; ( u -- b u : turn *u* into number string )
: u.r >r (u.) r> fallthrough; ( u +n -- : print u right justified by +n)
h: adjust over- spaces type ; ( b n n -- )
h: d5u.r dup fallthrough; ( u -- u )
h: 5u.r space 5 u.r space ; ( u -- )
( : .r >r (.)( r> adjust ; ( n n -- : print n, right justified by +n )
: u. (u.) h: blt space type ;; ( u -- : print unsigned number )
: . (.) blt ; ( n -- print number )
( : >base swap base @ >r base ! execute r> base ! ; )
( : d. $a ' . >base ; )
( : h. $10 ' u. >base ; )
h: adown cell negate and ; ( a -- a : align down )
xchange _forth-wordlist _system
: pack$ ( b u a -- a ) \ null fill
aligned dup>r over
dup adown
- over+ zero 2dup c! 1+ swap ( 2dup 0 fill ) cmove r> ;
xchange _system _forth-wordlist
: compare ( a1 u1 a2 u2 -- n : string equality )
rot
over- ?dup if >r 2drop r> nip exit then
for ( a1 a2 )
aft
count rot count rot - ?dup
if rdrop nip-nip exit then
then
next 2drop-0 ;
h: ^h ( bot eot cur -- bot eot cur )
>r over r@ < dup
if
=bs dup echo =bl echo echo
then r> + ;
h: tap dup echo over c! 1+ ; ( bot eot cur c -- bot eot cur )
h: delete? dup =bs = swap =del = or 0= ; ( c -- t : delete key pressed? )
h: ktap ( bot eot cur c -- bot eot cur )
dup =cr xor
if delete? \ =bs xor
if =bl tap exit then ^h exit
then drop nip dup ;
\ h: ktap? dup =bl - $5F u< swap =del xor and ; ( c -- t : possible ktap? )
: accept ( b u -- b u )
over+ over
begin
2dup-xor
while
key dup =bl - $5F u< if tap else <tap> @execute then
repeat drop over- ;
: expect <expect> @execute span ! drop ; ( b u -- )
: query tib tib-length <expect> @execute #tib ! drop-0 fallthrough;
h: in! >in ! ; ( u -- )
h: word.count count fallthrough; ( nfa -- u : get a words length )
h: word.length $1F and ;
xchange _forth-wordlist _system
: nfa cell+ ; ( pwd -- nfa : move to name field address)
: cfa nfa dup c@ word.length + cell+ adown ; ( pwd -- cfa )
xchange _system _forth-wordlist
h: .id nfa word.count type space ; ( pwd -- : print out a word )
h: immediate? nfa $40 fallthrough; ( pwd -- t : is word immediate? )
h: set? swap @ and 0<> ; ( a u -- t : is any of 'u' set? )
h: compile-only? nfa $20 set? ; ( pwd -- t : is word compile only? )
h: inline? inline-start inline-end within ; ( pwd -- t : is word inline? )
h: (search-wordlist) ( a wid -- PWD PWD 1|PWD PWD -1|0 a 0: find word in WID )
swap >r-dup
begin
dup
while
dup nfa count $9F ( $1F:word-length + $80:hidden ) and r@ count compare 0=
if ( found! )
rdrop
dup immediate? 1 or negate exit
then
nip dup@
repeat
rdrop 2drop-0 ;
h: (find) ( a -- pwd pwd 1 | pwd pwd -1 | 0 a 0 : find a word dictionary )
>r
context
begin
dup@
while
dup@ @ r@ swap (search-wordlist) ?dup
if
>r rot-drop r>rdrop exit
then
cell+
repeat drop-0 r> 0x0000 ;
: search-wordlist (search-wordlist) rot-drop ; ( a wid -- PWD 1|PWD -1|a 0 )
: find ( a -- pwd 1 | pwd -1 | a 0 : find a word in the dictionary )
(find) rot-drop ;
h: digit? ( c base -- u f )
>r [char] 0 - 9 over <
if
7 -
dup $A < or
then dup r> u< ;
: >number ( ud b u -- ud b u : convert string to number )
begin
( get next character )
2dup 2>r drop c@ base@ digit?
0= if ( d char )
drop ( d char -- d )
2r> ( restore string )
nop exit ( ..exit )
then ( d char )
swap base@ um* drop rot base@ um* d+ ( accumulate digit )
2r> ( restore string )
+string dup 0= ( advance string and test for end )
until ;
h: number? ( a u -- d -1 | a u 0 )
[-1] dpl !
base@ >r
string@ [char] - = dup>r if +string then
string@ [char] $ = if hex +string then
2>r 0 dup 2r>
begin
>number dup
while string@ [char] . ( fsp @ ) xor
if rot-drop rot r> 2drop-0 r> base! exit then
1- dpl ! 1+ dpl @
repeat 2drop r> if dnegate then r> base! [-1] ;
h: -trailing ( b u -- b u : remove trailing spaces )
for
aft =bl over r@ + c@ <
if r> 1+ exit then
then
next 0x0000 ;
h: lookfor ( b u c xt -- b u : skip until *xt* test succeeds )
swap >r -rot
begin
dup
while
string@ r@ - r@ =bl = 4 pick execute
if rdrop rot-drop exit then
+string
repeat rdrop rot-drop ;
h: no-match if 0> exit then 0<> ; ( n f -- t )
h: match no-match invert ; ( n f -- t )
h: parser ( b u c -- b u delta )
>r over r> swap 2>r
r@ ' no-match lookfor 2dup
r> ' match lookfor swap r> - >r - r> 1+ ;
: parse ( c -- b u ; <string> )
>r tib in@ + #tib @ in@ - r@ parser >in +!
r> =bl = if -trailing then 0 max ;
: ) ; immediate ( -- : do nothing )
: ( [char] ) parse 2drop ; immediate \ ) ( parse until matching paren )
: .( [char] ) parse type ; ( print out text until matching parenthesis )
: \ #tib @ in! ; immediate ( comment until new line )
h: ?length dup word-length u< ?exit $13 -throw ;
: word 1depth parse ?length here pack$ ; ( c -- a ; <string> )
h: token =bl word ; ( -- a )
: char token count drop c@ ; ( -- c; <string> )
h: ?dictionary dup $3B00 u< ?exit 8 -throw ;
: , here dup cell+ ?dictionary cp! ! ; ( u -- : store *u* in dictionary )
: 2, , , ; ( u u -- )
: c, here ?dictionary c! cp 1+! ; ( c -- : store *c* in the dictionary )
h: doLit 0x8000 or , ; ( n+ -- : compile literal )
: literal ( n -- : write a literal into the dictionary )
dup 0x8000 and ( n > $7FFF ? )
if
invert doLit =invert , exit ( store inversion of n the invert it )
then
doLit ; compile-only immediate ( turn into literal, write into dictionary )
h: make-callable chars $4000 or ; ( cfa -- instruction )
: compile, make-callable , ; ( cfa -- : compile a code field address )
h: $compile dup inline? if cfa @ , exit then cfa compile, ; ( pwd -- )
h: not-found source type $D -throw ; ( -- : throw 'word not found' )
h: ?compile dup compile-only? 0= ?exit source type $E -throw ;
xchange _forth-wordlist _system
: (literal) state@ 0= ?exit postpone literal ; ( u -- u | )
xchange _system _forth-wordlist
: interpret ( ??? a -- ??? : The command/compiler loop )
\ dup count type space ( <- for tracing the parser )
find ?dup if
state@
if
0> if cfa execute exit then \ <- immediate word are executed
$compile exit \ <- compiling word are...compiled.
then
drop ?compile \ <- check it's not a compile only word word
cfa execute exit \ <- if its not, execute it, then exit *interpreter*
then
\ not a word
dup>r count number? if rdrop \ it's a number!
dpl @ 0< if \ <- dpl will -1 if its a single cell number
drop \ drop high cell from 'number?' for single cell output
else \ <- dpl is not -1, it's a double cell number
state@ if swap then
<literal> @execute \ <literal> is executed twice if it's a double
then
<literal> @execute exit
then
r> not-found ; \ not a word/number, it's an error! NB. We could vector this
: compile r> dup@ , cell+ >r ; compile-only ( --:Compile next compiled word )
: immediate $40 last nfa fallthrough; ( -- : previous word immediate )
h: toggle tuck @ xor swap! ; ( u a -- : xor value at addr with u )
h: count+ count + ; ( b -- b : advance address over counted string )
h: do$ 2r> dup count+ aligned >r swap >r ; ( -- a )
h: string-literal do$ nop ; ( -- a : do string NB. nop to fool optimizer )
h: .string do$ fallthrough; ( -- : print string )
h: print count type ; ( b -- )
[t] .string tdoPrintString meta!
[t] string-literal tdoStringLit meta!
( <string>, --, Run: -- b )
: $" compile string-literal fallthrough; immediate compile-only
h: parse-string [char] " word count+ cp! ; ( ccc" -- )
: ." compile .string parse-string ; immediate compile-only ( <string>, -- )
: abort [-1] throw ; ( -- )
h: ?abort swap if print cr abort exit then drop ; ( u a -- )
h: (abort) do$ ?abort ; ( -- )
: abort" compile (abort) parse-string ; immediate compile-only ( u -- )
\ See:
\ <https://b2d-f9r.blogspot.com/2010/08/16-bit-xorshift-rng-now-with-more.html>
\
\ For a super tiny N-bit PRNG use; "x+=(x*x) | 5;", you can only use the
\ highest bit however.
\ See: <http://www.woodmann.com/forum/showthread.php?3100-super-tiny-PRNG>
: random
seed1 @ dup 5 lshift-xor
seed2 @ seed1 !
dup 3 rshift-xor
seed2 @ dup 1 rshift-xor xor dup seed2 ! ;
h: 40ns begin dup while 1- repeat drop ; ( n -- : wait for 'n'*40ns + 30us )
: ms for 25000 40ns next ; ( n -- : wait for 'n' milliseconds )
\ ============================================================================
\ # I/O wordset
xchange _forth-wordlist _system
: segments! $400E ! ; ( u -- : write to 4 7-segment hex displays )
: led! $4006 ! ; ( u -- : write to 8 LEDs )
: switches $4006 @ ; ( -- u : retrieve switch on/off for 8 switches )
: timer! $4004 ! ; ( u -- : set timer and timer control )
: timer $4004 @ ; ( -- u : get timer and timer control )
\ NB. Perhaps this could be vectored?
h: (irq)
( cpu? 0 cpu! )
switches led!
#irq dup@ segments! 1+!
( cpu! ) ;
[t] (irq) 2/ $C t!
: irq $0040 $4010 ! [-1] timer! 1 cpu! ;
\ FIFO: Write Read Enable after Read
\ h: uart? ( uart-register -- c -1 | 0 : generic UART input functions )
\ dup@ $0100 and if drop 0x0000 exit then dup@ $FF and swap $0400 swap! [-1] ;
\ FIFO: Write Read Enable before Read
h: uart? ( uart-register -- c -1 | 0 : generic UART input functions )
dup@ $0100 and if drop-0 exit then dup $0400 swap! @ lsb [-1] ;
: rx? $4000 uart? if [-1] exit then $4002 uart? ; ( -- c -1|0: rx uart/ps2 )
h: uart! ( c uart-register -- )
begin dup@ $1000 and 0= until swap $2000 or swap! ;
: tx! dup $4002 uart! ( VGA/VT-100 ) $4000 uart! ( UART ) ;
h: (ok) state@ if cr exit then ." ok" cr ; ( -- : default state aware prompt )
h: preset tib-start #tib cell+ ! 0 in! id zero ; ( -- : reset input )
: io! \ preset
( 115200 / 9600 )
$35 ( $28B ) $4012 ! ( set TX baud rate - 54 )
$34 ( $28A ) $4014 ! ( set RX baud rate - 53, hack! )
$8080 $4016 ! ( set UART control register; 8 bits, 1 stop, no parity )
0 timer! 0 led! cpu-id segments!
0 cpu! 0 $4010 ! ( set IRQ mask )
fallthrough; ( -- : initialize I/O )
h: console ' rx? <key> ! ' tx! <emit> ! fallthrough;
h: hand
' (ok)
' emit ' ktap
fallthrough;
h: xio ' accept <expect> ! <tap> ! <echo> ! <ok> ! ;
h: pace [char] . emit ;
: file ' pace ' drop ' ktap xio ;
\ ============================================================================
\ # Evaluation, Control Structures and Vocabulary Words
\ h: pace 11 emit ;
\ : file ' pace ' drop ' ktap xio ;
xchange _system _forth-wordlist
: ] [-1] state ! ; ( -- : compile mode )
: [ state zero ; immediate ( -- : command mode )
h: empty sp@ ndrop ; ( 0..n -- : empty variable stack )
h: ?error ( n -- : perform actions on error )
?dup 0= ?exit
. ( print error number )
[char] ? emit ( print '?' )
cr ( and terminate the line )
empty ( empty the variable stack )
fallthrough;
h: prequit ( perform actions needed to start 'quit' off )
preset ( reset I/O streams )
postpone [ ; ( back into interpret mode )
h: eval ( -- : evaluation loop, get token, evaluate, loop, prompt )
begin
token dup c@
while
interpret 0 ?depth
repeat drop <ok> @execute ;
: quit prequit begin query ' eval catch ?error again ;
h: get-input source in@ source-id <ok> @ ; ( -- n1...n5 )
h: set-input <ok> ! id ! in! #tib 2! ; ( n1...n5 -- )
: evaluate ( a u -- )
get-input 2>r 2>r >r
0 [-1] 0 set-input
' eval catch
r> 2r> 2r> set-input
throw ;
h: ?check ( magic-number -- : check for magic number on the stack )
magic = ?exit $16 -throw ;
h: ?unique ( a -- a : print a message if a word definition is not unique )
dup get-current (search-wordlist) 0= ?exit
( source type )
space
2drop last-def @ .id ." redefined" cr ;
h: ?nul ( b -- : check for zero length strings )
dup c@ ?exit $A -throw ;
h: find-token token find fallthrough; ( -- pwd, <string> )
h: ?not-found ?exit not-found ; ( t -- )
h: find-cfa find-token cfa ; ( -- xt, <string> )
: ' find-cfa state@ if postpone literal exit then ; immediate
: [compile] find-cfa compile, ; immediate compile-only ( --, <string> )
: [char] char postpone literal ; immediate compile-only ( --, <string> )
: ; ?check =exit , postpone [ ( -- wid )
( h: get-current! ) ?dup if get-current ! exit then ; immediate compile-only
: : align here dup last-def ! ( "name", -- colon-sys )
last , token ?nul ?unique count+ cp! magic postpone ] ;
: begin here ; immediate compile-only ( -- a )
: again chars , ; immediate compile-only ( a -- )
: until $4000 or postpone again ; immediate compile-only ( a --, NB. again !? )
h: here-0 here 0x0000 ;
h: >mark here-0 postpone again ;
: if here-0 postpone until ; immediate compile-only
( : unless ' 0= compile, postpone if ; immediate compile-only )
: then fallthrough; immediate compile-only
h: >resolve here chars over @ or swap! ;
: else >mark swap >resolve ; immediate compile-only
: while postpone if ; immediate compile-only
: repeat swap postpone again postpone then ; immediate compile-only
h: last-cfa last-def @ cfa ; ( -- u )
: recurse last-cfa compile, ; immediate compile-only
: create postpone : drop compile doVar get-current ! postpone [ ;
: >body cell+ ; ( a -- a )
h: doDoes r> chars here chars last-cfa dup cell+ doLit h: !, ! , ;;
: does> compile doDoes nop ; immediate compile-only
: variable create 0 , ;
: constant create ' doConst make-callable here cell- !, ;
: :noname here-0 magic postpone ] ; ( NB. need postpone! )
: for =>r , here ; immediate compile-only
: next compile doNext , ; immediate compile-only
: aft drop >mark postpone begin swap ; immediate compile-only
: marker ( "name", -- : create an eraser )
here >r current @ dup@ r>
create , 2,
doDoes ( <- meta-compiler version of does> )
dup cell+ 2@ swap! @ here - allot ;
\ h: (do) r@ swap rot >r >r cell+ >r ; ( hi lo -- index )
\ : do compile (do) 0 , here ; compile-only immediate ( hi lo -- )
\ h: (leave) rdrop rdrop rdrop ; compile-only
\ : leave compile (leave) nop ; compile-only immediate
\ h: (loop)
\ r> r> 1+ r> 2dup-xor if
\ >r >r @ >r exit
\ then >r 1- >r cell+ >r ; compile-only
\ h: (unloop) r>rdrop rdrop rdrop >r ; compile-only
\ : unloop compile (unloop) nop ; compile-only immediate
\ h: (?do)
\ 2dup-xor if r@ swap rot >r >r cell+ >r exit then 2drop ; compile-only
\ : ?do compile (?do) 0 , here ; compile-only immediate ( hi lo -- )
\ : loop compile (loop) dup , compile (unloop) cell- here chars ( -- )
\ swap! ; compile-only immediate
\ h: (+loop)
\ r> swap r> r> 2dup - >r
\ 2 pick r@ + r@ xor 0< 0=
\ 3 pick r> xor 0< 0= or if
\ >r + >r @ >r exit
\ then >r >r drop cell+ >r ; compile-only
\ : +loop ( n -- ) compile (+loop) dup , compile
\ (unloop) cell- here chars swap! ; compile-only immediate
\ h: (i) 2r> tuck 2>r nop ; compile-only ( -- index )
\ : i compile (i) nop ; compile-only immediate ( -- index )
xchange _forth-wordlist _system
: hide find-token nfa $80 swap toggle ; ( --, <string> : hide word by name )
xchange _system _forth-wordlist
: get-order ( -- widn ... wid1 n : get the current search order )
context
0
( : find-cell ) >r begin dup@ r@ xor while cell+ repeat rdrop ( ; u a -- a )
dup cell- swap
context - chars dup>r 1- s>d if $32 -throw exit then
for aft dup@ swap cell- then next @ r> ;
xchange _forth-wordlist root-voc
: forth-wordlist _forth-wordlist ; ( -- wid : push forth vocabulary )
: system _system ; ( -- wid : push system vocabulary )
: set-order ( widn ... wid1 n -- : set the current search order )
dup [-1] = if drop root-voc 1 set-order exit then ( NB. Recursion! )
dup #vocs > if $31 -throw exit then
context swap for aft tuck! cell+ then next zero ;
: forth root-voc forth-wordlist 2 set-order ; ( -- )
: words
get-order begin ?dup while
swap dup cr u. colon-space @
begin
?dup