mirror of
https://github.com/kanaka/mal.git
synced 2024-09-20 01:57:09 +03:00
bbab5c5d38
- Metadata support required expanding the type size (to 5 bits). This
also implies that ref cnt now only has 11 bits (2048).
- Added ^ reader macro (with-meta) which required some refactoring of
READ_MACRO to share code.
- Rename some more variables:
ZJ -> S
S% -> X%
ZR% -> Y%
ZM% -> Y
RE% -> D
This removes remaining % variables apart from the pre-allocated
arrays Z%, S% and X%.
536 lines
13 KiB
QBasic
536 lines
13 KiB
QBasic
REM Z 0 -> 1
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REM nil 0 -> (unused)
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REM boolean 1 -> 0: false, 1: true
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REM integer 2 -> int value
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REM float 3 -> ???
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REM string/kw 4 -> S$ index
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REM symbol 5 -> S$ index
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REM list next/val 6 -> next Z% index (0 for last)
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REM 14 value (unless empty)
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REM vector next/val 7 -> next Z% index (0 for last)
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REM 14 value (unless empty)
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REM hashmap next/val 8 -> next Z% index (0 for last)
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REM 14 key/value (alternating)
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REM function 9 -> function index
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REM mal function 10 -> body AST Z% index
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REM param env Z% index
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REM macro (same as 10) 11 -> body AST Z% index
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REM param env Z% index
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REM atom 12 -> Z% index
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REM environment 13 -> data/hashmap Z% index
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REM 14 outer Z% index (-1 for none)
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REM reference/ptr 14 -> Z% index / or 0
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REM next free ptr 15 -> Z% index / or 0
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REM metadata 16-31 -> Z% index of object with this metadata
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REM 14 -> Z% index of metdata object
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INIT_MEMORY:
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T=FRE(0)
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Z1=2048+512: REM Z% (boxed memory) size (4 bytes each)
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Z2=256: REM S$ (string memory) size (3 bytes each)
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Z3=256: REM X% (call stack) size (2 bytes each)
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Z4=64: REM Y% (release stack) size (4 bytes each)
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REM global error state
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REM -2 : no error
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REM -1 : string error in ER$
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REM >=0 : pointer to error object
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ER=-2
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ER$=""
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REM boxed element memory
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DIM Z%(Z1,1): REM TYPE ARRAY
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REM Predefine nil, false, true, and an empty list
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Z%(0,0)=0:Z%(0,1)=0
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Z%(1,0)=1:Z%(1,1)=0
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Z%(2,0)=1:Z%(2,1)=1
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Z%(3,0)=6+32:Z%(3,1)=0
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Z%(4,0)=0:Z%(4,1)=0
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REM start of unused memory
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ZI=5
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REM start of free list
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ZK=5
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REM string memory storage
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S=0:DIM S$(Z2)
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REM call/logic stack
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X=-1:DIM X%(Z3): REM stack of Z% indexes
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REM pending release stack
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Y=-1:DIM Y%(Z4,1): REM stack of Z% indexes
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REM PRINT "Lisp data memory: "+STR$(T-FRE(0))
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REM PRINT "Interpreter working memory: "+STR$(FRE(0))
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RETURN
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REM memory functions
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REM ALLOC(T,L) -> R
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REM ALLOC(T,L,N) -> R
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REM ALLOC(T,L,M,N) -> R
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REM L is default for Z%(R,1)
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REM M is default for Z%(R+1,0), if relevant for T
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REM N is default for Z%(R+1,1), if relevant for T
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ALLOC:
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SZ=2
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IF T<6 OR T=9 OR T=12 OR T=14 THEN SZ=1
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REM PRINT "ALLOC T: "+STR$(T)+", SZ: "+STR$(SZ)+", ZK: "+STR$(ZK)
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U3=ZK
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U4=ZK
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ALLOC_LOOP:
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IF U4=ZI THEN GOTO ALLOC_UNUSED
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REM TODO sanity check that type is 15
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IF ((Z%(U4,0)AND-32)/32)=SZ THEN GOTO ALLOC_MIDDLE
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REM PRINT "ALLOC search: U3: "+STR$(U3)+", U4: "+STR$(U4)
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U3=U4: REM previous set to current
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U4=Z%(U4,1): REM current set to next
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GOTO ALLOC_LOOP
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ALLOC_MIDDLE:
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REM PRINT "ALLOC_MIDDLE: U3: "+STR$(U3)+", U4: "+STR$(U4)
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R=U4
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REM set free pointer (ZK) to next free
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IF U4=ZK THEN ZK=Z%(U4,1)
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REM set previous free to next free
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IF U4<>ZK THEN Z%(U3,1)=Z%(U4,1)
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GOTO ALLOC_DONE
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ALLOC_UNUSED:
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REM PRINT "ALLOC_UNUSED ZI: "+STR$(ZI)+", U3: "+STR$(U3)+", U4: "+STR$(U4)
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R=U4
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ZI=ZI+SZ
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IF U3=U4 THEN ZK=ZI
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REM set previous free to new memory top
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IF U3<>U4 THEN Z%(U3,1)=ZI
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GOTO ALLOC_DONE
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ALLOC_DONE:
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Z%(R,0)=T+32
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REM set Z%(R,1) to default L
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IF T>=6 AND T<>9 AND L>0 THEN Z%(L,0)=Z%(L,0)+32
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Z%(R,1)=L
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IF SZ=1 THEN RETURN
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Z%(R+1,0)=14: REM default for 6-8, and 13, and >=16 (metadata)
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REM function/macro sets Z%(R+1,0) to default M
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IF T=10 OR T=11 THEN Z%(M,0)=Z%(M,0)+32:Z%(R+1,0)=M
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REM seq, function/macro, environment sets Z%(R+1,1) to default N
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IF N>0 THEN Z%(N,0)=Z%(N,0)+32
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Z%(R+1,1)=N
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RETURN
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REM FREE(AY, SZ) -> nil
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FREE:
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REM assumes reference count cleanup already (see RELEASE)
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Z%(AY,0)=(SZ*32)+15: REM set type(15) and size
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Z%(AY,1)=ZK
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ZK=AY
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IF SZ>=2 THEN Z%(AY+1,0)=0:Z%(AY+1,1)=0
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IF SZ>=3 THEN Z%(AY+2,0)=0:Z%(AY+2,1)=0
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RETURN
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REM RELEASE(AY) -> nil
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REM R should not be affected by this call
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RELEASE:
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RC=0
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GOTO RELEASE_ONE
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RELEASE_TOP:
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IF RC=0 THEN RETURN
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REM pop next object to release, decrease remaining count
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AY=X%(X):X=X-1
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RC=RC-1
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RELEASE_ONE:
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REM nil, false, true
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IF AY<3 THEN GOTO RELEASE_TOP
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U6=Z%(AY,0)AND31: REM type
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REM AZ=AY: PR=1: GOSUB PR_STR
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REM PRINT "RELEASE AY:"+STR$(AY)+"["+R$+"] (byte0:"+STR$(Z%(AY,0))+")"
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REM sanity check not already freed
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IF (U6)=15 THEN ER=-1:ER$="Free of free memory: "+STR$(AY):RETURN
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IF U6=14 THEN GOTO RELEASE_REFERENCE
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IF Z%(AY,0)<15 THEN ER=-1:ER$="Free of freed object: "+STR$(AY):RETURN
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REM decrease reference count by one
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Z%(AY,0)=Z%(AY,0)-32
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REM our reference count is not 0, so don't release
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IF Z%(AY,0)>=32 GOTO RELEASE_TOP
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REM switch on type
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IF (U6<=5) OR (U6=9) THEN GOTO RELEASE_SIMPLE
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IF (U6>=6) AND (U6<=8) THEN GOTO RELEASE_SEQ
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IF U6=10 OR U6=11 THEN GOTO RELEASE_MAL_FUNCTION
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IF U6>=16 THEN GOTO RELEASE_METADATA
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IF U6=12 THEN GOTO RELEASE_ATOM
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IF U6=13 THEN GOTO RELEASE_ENV
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IF U6=15 THEN ER=-1:ER$="RELEASE of already freed: "+STR$(AY):RETURN
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ER=-1:ER$="RELEASE not defined for type "+STR$(U6):RETURN
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RELEASE_SIMPLE:
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REM simple type (no recursing), just call FREE on it
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SZ=1:GOSUB FREE
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GOTO RELEASE_TOP
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RELEASE_SIMPLE_2:
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REM free the current element and continue
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SZ=2:GOSUB FREE
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GOTO RELEASE_TOP
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RELEASE_SEQ:
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IF Z%(AY,1)=0 THEN GOTO RELEASE_SIMPLE_2
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IF Z%(AY+1,0)<>14 THEN ER=-1:ER$="invalid list value"+STR$(AY+1):RETURN
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REM add value and next element to stack
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RC=RC+2:X=X+2
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X%(X-1)=Z%(AY+1,1):X%(X)=Z%(AY,1)
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GOTO RELEASE_SIMPLE_2
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RELEASE_ATOM:
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REM add contained/referred value
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RC=RC+1:X=X+1:X%(X)=Z%(AY,1)
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REM free the atom itself
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GOTO RELEASE_SIMPLE
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RELEASE_MAL_FUNCTION:
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REM add ast, params and environment to stack
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RC=RC+3:X=X+3
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X%(X-2)=Z%(AY,1):X%(X-1)=Z%(AY+1,0):X%(X)=Z%(AY+1,1)
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REM free the current 2 element mal_function and continue
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SZ=2:GOSUB FREE
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GOTO RELEASE_TOP
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RELEASE_METADATA:
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REM add object and metadata object
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RC=RC+2:X=X+2
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X%(X-1)=Z%(AY,1):X%(X)=Z%(AY+1,1)
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SZ=2:GOSUB FREE
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GOTO RELEASE_TOP
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RELEASE_ENV:
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REM add the hashmap data to the stack
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RC=RC+1:X=X+1:X%(X)=Z%(AY,1)
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REM if no outer set
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IF Z%(AY+1,1)=-1 THEN GOTO RELEASE_ENV_FREE
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REM add outer environment to the stack
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RC=RC+1:X=X+1:X%(X)=Z%(AY+1,1)
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RELEASE_ENV_FREE:
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REM free the current 2 element environment and continue
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SZ=2:GOSUB FREE
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GOTO RELEASE_TOP
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RELEASE_REFERENCE:
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IF Z%(AY,1)=0 THEN GOTO RELEASE_SIMPLE
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REM add the referred element to the stack
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RC=RC+1:X=X+1:X%(X)=Z%(AY,1)
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REM free the current element and continue
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SZ=1:GOSUB FREE
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GOTO RELEASE_TOP
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REM RELEASE_PEND(LV) -> nil
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RELEASE_PEND:
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IF Y<0 THEN RETURN
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IF Y%(Y,1)<=LV THEN RETURN
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REM PRINT "RELEASE_PEND releasing:"+STR$(Y%(Y,0))
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AY=Y%(Y,0):GOSUB RELEASE
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Y=Y-1
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GOTO RELEASE_PEND
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REM DEREF_R(R) -> R
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DEREF_R:
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IF (Z%(R,0)AND31)=14 THEN R=Z%(R,1):GOTO DEREF_R
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RETURN
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REM DEREF_A(A) -> A
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DEREF_A:
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IF (Z%(A,0)AND31)=14 THEN A=Z%(A,1):GOTO DEREF_A
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RETURN
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REM DEREF_B(B) -> B
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DEREF_B:
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IF (Z%(B,0)AND31)=14 THEN B=Z%(B,1):GOTO DEREF_B
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RETURN
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REM general functions
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REM EQUAL_Q(A, B) -> R
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EQUAL_Q:
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GOSUB DEREF_A
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GOSUB DEREF_B
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R=0
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U1=Z%(A,0)AND31
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U2=Z%(B,0)AND31
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IF NOT (U1=U2 OR ((U1=6 OR U1=7) AND (U2=6 OR U2=7))) THEN RETURN
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IF U1=6 THEN GOTO EQUAL_Q_SEQ
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IF U1=7 THEN GOTO EQUAL_Q_SEQ
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IF U1=8 THEN GOTO EQUAL_Q_HM
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IF Z%(A,1)=Z%(B,1) THEN R=1
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RETURN
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EQUAL_Q_SEQ:
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IF (Z%(A,1)=0) AND (Z%(B,1)=0) THEN R=1:RETURN
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IF (Z%(A,1)=0) OR (Z%(B,1)=0) THEN R=0:RETURN
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REM push A and B
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X=X+2:X%(X-1)=A:X%(X)=B
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REM compare the elements
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A=Z%(A+1,1):B=Z%(B+1,1):GOSUB EQUAL_Q
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REM pop A and B
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A=X%(X-1):B=X%(X):X=X-2
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IF R=0 THEN RETURN
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REM next elements of the sequences
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A=Z%(A,1):B=Z%(B,1):GOTO EQUAL_Q_SEQ
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EQUAL_Q_HM:
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R=0
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RETURN
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REM string functions
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REM STRING_(AS$) -> R
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REM intern string (returns string index, not Z% index)
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STRING_:
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IF S=0 THEN GOTO STRING_NOT_FOUND
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REM search for matching string in S$
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FOR I=0 TO S-1
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IF AS$=S$(I) THEN R=I:RETURN
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NEXT I
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STRING_NOT_FOUND:
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S$(S)=AS$
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R=S
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S=S+1
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RETURN
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REM STRING(AS$, T) -> R
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REM intern string and allocate reference (return Z% index)
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STRING:
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GOSUB STRING_
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L=R:GOSUB ALLOC
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RETURN
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REM REPLACE(R$, S1$, S2$) -> R$
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REPLACE:
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T3$=R$
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R$=""
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I=1
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J=LEN(T3$)
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REPLACE_LOOP:
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IF I>J THEN RETURN
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CH$=MID$(T3$,I,LEN(S1$))
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IF CH$=S1$ THEN R$=R$+S2$:I=I+LEN(S1$)
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IF CH$<>S1$ THEN R$=R$+MID$(T3$,I,1):I=I+1
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GOTO REPLACE_LOOP
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REM sequence functions
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REM FORCE_SEQ_TYPE(A,T) -> R
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FORCE_SEQ_TYPE:
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REM if it's already the right type, inc ref cnt and return it
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IF (Z%(A,0)AND31)=T THEN R=A:Z%(R,0)=Z%(R,0)+32:RETURN
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REM otherwise, copy first element to turn it into correct type
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B=A+1:GOSUB DEREF_B: REM value to copy
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L=Z%(A,1):N=B:GOSUB ALLOC: REM T already set
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IF Z%(A,1)=0 THEN RETURN
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RETURN
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REM LIST_Q(A) -> R
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LIST_Q:
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R=0
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IF (Z%(A,0)AND31)=6 THEN R=1
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RETURN
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REM EMPTY_Q(A) -> R
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EMPTY_Q:
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R=0
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IF Z%(A,1)=0 THEN R=1
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RETURN
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REM COUNT(A) -> R
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COUNT:
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R=-1
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DO_COUNT_LOOP:
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R=R+1
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IF Z%(A,1)<>0 THEN A=Z%(A,1):GOTO DO_COUNT_LOOP
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RETURN
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REM LAST(A) -> R
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LAST:
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REM TODO check that actually a list/vector
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IF Z%(A,1)=0 THEN R=0:RETURN: REM empty seq, return nil
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T6=0
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LAST_LOOP:
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IF Z%(A,1)=0 THEN GOTO LAST_DONE: REM end, return previous value
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T6=A: REM current becomes previous entry
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A=Z%(A,1): REM next entry
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GOTO LAST_LOOP
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LAST_DONE:
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R=T6+1:GOSUB DEREF_R
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Z%(R,0)=Z%(R,0)+32
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RETURN
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REM SLICE(A,B,C) -> R
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REM make copy of sequence A from index B to C
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REM returns R6 as reference to last element of slice
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REM returns A as next element following slice (of original)
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SLICE:
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I=0
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R5=-1: REM temporary for return as R
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R6=0: REM previous list element
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SLICE_LOOP:
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REM always allocate at least one list element
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T=6:L=0:N=0:GOSUB ALLOC
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IF R5=-1 THEN R5=R
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IF R5<>-1 THEN Z%(R6,1)=R
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REM advance A to position B
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SLICE_FIND_B:
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IF I<B AND Z%(A,1)<>0 THEN A=Z%(A,1):I=I+1:GOTO SLICE_FIND_B
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REM if current position is C, then return
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IF C<>-1 AND I>=C THEN R=R5:RETURN
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REM if we reached end of A, then return
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IF Z%(A,1)=0 THEN R=R5:RETURN
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R6=R: REM save previous list element
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REM copy value and inc ref cnt
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Z%(R6+1,1)=Z%(A+1,1)
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R=A+1:GOSUB DEREF_R:Z%(R,0)=Z%(R,0)+32
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REM advance to next element of A
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A=Z%(A,1)
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I=I+1
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GOTO SLICE_LOOP
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REM LIST2(B2,B1) -> R
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LIST2:
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REM last element is 3 (empty list), second element is B1
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T=6:L=3:N=B1:GOSUB ALLOC
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REM first element is B2
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T=6:L=R:N=B2:GOSUB ALLOC
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AY=L:GOSUB RELEASE: REM new list takes ownership of previous
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RETURN
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REM LIST3(B3,B2,B1) -> R
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LIST3:
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GOSUB LIST2
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REM first element is B3
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T=6:L=R:N=B3:GOSUB ALLOC
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AY=L:GOSUB RELEASE: REM new list takes ownership of previous
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RETURN
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REM hashmap functions
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REM HASHMAP() -> R
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HASHMAP:
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T=8:L=0:N=0:GOSUB ALLOC
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RETURN
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REM ASSOC1(H, K, V) -> R
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ASSOC1:
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REM deref K and V
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R=V:GOSUB DEREF_R:V=R
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R=K:GOSUB DEREF_R:K=R
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REM value ptr
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T=8:L=H:N=V:GOSUB ALLOC
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AY=L:GOSUB RELEASE: REM we took ownership of previous hashmap
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REM key ptr
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T=8:L=R:N=K:GOSUB ALLOC
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AY=L:GOSUB RELEASE: REM we took ownership of previous hashmap
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RETURN
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REM ASSOC1(H, K$, V) -> R
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ASSOC1_S:
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S$(S)=K$
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REM add the key string
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T=4:L=S:GOSUB ALLOC
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S=S+1
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K=R:GOSUB ASSOC1
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AY=K:GOSUB RELEASE: REM map took ownership of key
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RETURN
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REM HASHMAP_GET(H, K) -> R
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HASHMAP_GET:
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H2=H
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T1$=S$(Z%(K,1)): REM search key string
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T3=0: REM whether found or not (for HASHMAP_CONTAINS)
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R=0
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HASHMAP_GET_LOOP:
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REM no matching key found
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IF Z%(H2,1)=0 THEN R=0:RETURN
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REM follow value ptrs
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|
T2=H2+1
|
|
HASHMAP_GET_DEREF:
|
|
IF Z%(T2,0)=14 THEN T2=Z%(T2,1):GOTO HASHMAP_GET_DEREF
|
|
REM get key string
|
|
T2$=S$(Z%(T2,1))
|
|
REM if they are equal, we found it
|
|
IF T1$=T2$ THEN T3=1:R=Z%(H2,1)+1:RETURN
|
|
REM skip to next key
|
|
H2=Z%(Z%(H2,1),1)
|
|
GOTO HASHMAP_GET_LOOP
|
|
|
|
REM HASHMAP_CONTAINS(H, K) -> R
|
|
HASHMAP_CONTAINS:
|
|
GOSUB HASHMAP_GET
|
|
R=T3
|
|
RETURN
|
|
|
|
|
|
REM function functions
|
|
|
|
REM NATIVE_FUNCTION(A) -> R
|
|
NATIVE_FUNCTION:
|
|
T=9:L=A:GOSUB ALLOC
|
|
RETURN
|
|
|
|
REM MAL_FUNCTION(A, P, E) -> R
|
|
MAL_FUNCTION:
|
|
T=10:L=A:M=P:N=E:GOSUB ALLOC
|
|
RETURN
|
|
|
|
REM APPLY(F, AR) -> R
|
|
REM restores E
|
|
APPLY:
|
|
REM if metadata, get the actual object
|
|
IF (Z%(F,0)AND31)>=16 THEN F=Z%(F,1)
|
|
|
|
IF (Z%(F,0)AND31)=9 THEN GOTO DO_APPLY_FUNCTION
|
|
IF (Z%(F,0)AND31)=10 THEN GOTO DO_APPLY_MAL_FUNCTION
|
|
IF (Z%(F,0)AND31)=11 THEN GOTO DO_APPLY_MAL_FUNCTION
|
|
|
|
DO_APPLY_FUNCTION:
|
|
GOSUB DO_FUNCTION
|
|
|
|
RETURN
|
|
|
|
DO_APPLY_MAL_FUNCTION:
|
|
X=X+1:X%(X)=E: REM save the current environment
|
|
|
|
REM create new environ using env and params stored in the
|
|
REM function and bind the params to the apply arguments
|
|
O=Z%(F+1,1):BI=Z%(F+1,0):EX=AR:GOSUB ENV_NEW_BINDS
|
|
|
|
A=Z%(F,1):E=R:GOSUB EVAL
|
|
|
|
AY=E:GOSUB RELEASE: REM release the new environment
|
|
|
|
E=X%(X):X=X-1: REM pop/restore the saved environment
|
|
|
|
RETURN
|
|
|