forth: fix IF/THEN/ELSE in colon defs
This commit is contained in:
parent
02b56c547a
commit
3996f0c825
@ -242,71 +242,35 @@ DEFINE:
|
||||
; All we need to do is to know how many bytes to copy. To do so, we
|
||||
; skip compwords until EXIT is reached.
|
||||
ex de, hl ; DE is our dest
|
||||
ld (HERE), de ; update HERE
|
||||
ld l, (ix)
|
||||
ld h, (ix+1)
|
||||
.loop:
|
||||
call HLPointsNUMBER
|
||||
jr nz, .notNUMBER
|
||||
; is number
|
||||
ld bc, 4
|
||||
ldir
|
||||
call HLPointsEXIT
|
||||
jr z, .loopend
|
||||
call compSkip
|
||||
jr .loop
|
||||
.notNUMBER:
|
||||
call HLPointsLIT
|
||||
jr nz, .notLIT
|
||||
; is lit
|
||||
ldi
|
||||
ldi
|
||||
call strcpyM
|
||||
jr .loop
|
||||
.notLIT:
|
||||
; it's a word
|
||||
call HLPointsIMMED
|
||||
jr nz, .notIMMED
|
||||
; Immediate word, we'll have to call it.
|
||||
; Before we make our call, let's save our current HL/DE position
|
||||
ld (CMPDST), de
|
||||
ld e, (hl)
|
||||
inc hl
|
||||
ld d, (hl)
|
||||
inc hl ; point to next word
|
||||
push de \ pop iy ; prepare for executeCodeLink
|
||||
ld (ix), l
|
||||
ld (ix+1), h
|
||||
; Push return address
|
||||
ld hl, .retList
|
||||
call pushRS
|
||||
; Ready!
|
||||
jp executeCodeLink
|
||||
.notIMMED:
|
||||
; a good old regular word. We have 2 bytes to copy. But before we do,
|
||||
; let's check whether it's an EXIT. LDI doesn't affect Z, so we can
|
||||
; make our jump later.
|
||||
call HLPointsEXITQUIT
|
||||
ldi
|
||||
ldi
|
||||
jr nz, .loop
|
||||
; HL has our new RS' TOS
|
||||
ld (ix), l
|
||||
ld (ix+1), h
|
||||
ld (HERE), de ; update HERE
|
||||
jp exit
|
||||
|
||||
; This label is pushed to RS when an IMMED word is called. When that word calls
|
||||
; exit, this is where it returns. When we return, RS will need to be popped so
|
||||
; that we stay on the proper RS level.
|
||||
.retList:
|
||||
.dw .retWord
|
||||
.retWord:
|
||||
.dw .retEntry
|
||||
.retEntry:
|
||||
call popRS ; unwind stack
|
||||
; recall old HL / DE values
|
||||
.loopend:
|
||||
; skip EXIT
|
||||
inc hl \ inc hl
|
||||
; We have out end offset. Let's get our offset
|
||||
ld e, (ix)
|
||||
ld d, (ix+1)
|
||||
or a ; clear carry
|
||||
sbc hl, de
|
||||
; HL is our copy count.
|
||||
ld b, h
|
||||
ld c, l
|
||||
ld l, (ix)
|
||||
ld h, (ix+1)
|
||||
ld de, (CMPDST)
|
||||
; continue!
|
||||
jr .loop
|
||||
ld de, (HERE) ; recall dest
|
||||
; copy!
|
||||
ldir
|
||||
ld (ix), l
|
||||
ld (ix+1), h
|
||||
ld (HERE), de
|
||||
jp exit
|
||||
|
||||
|
||||
.db "DOES>"
|
||||
.fill 3
|
||||
|
@ -123,7 +123,9 @@ forthInterpret:
|
||||
|
||||
.retRef:
|
||||
.dw $+2
|
||||
.dw forthInterpret
|
||||
.dw $+2
|
||||
call popRS
|
||||
jr forthInterpret
|
||||
|
||||
msgOk:
|
||||
.db " ok", 0
|
||||
|
@ -69,14 +69,28 @@ HLPointsLIT:
|
||||
pop de
|
||||
ret
|
||||
|
||||
HLPointsEXITQUIT:
|
||||
HLPointsBRANCH:
|
||||
push de
|
||||
ld de, BRANCH
|
||||
call HLPointsDE
|
||||
jr z, .end
|
||||
ld de, CBRANCH
|
||||
call HLPointsDE
|
||||
.end:
|
||||
pop de
|
||||
ret
|
||||
|
||||
HLPointsEXIT:
|
||||
push de
|
||||
ld de, EXIT
|
||||
call HLPointsDE
|
||||
jr z, .end
|
||||
pop de
|
||||
ret
|
||||
|
||||
HLPointsQUIT:
|
||||
push de
|
||||
ld de, QUIT
|
||||
call HLPointsDE
|
||||
.end:
|
||||
pop de
|
||||
ret
|
||||
|
||||
@ -85,7 +99,9 @@ HLPointsEXITQUIT:
|
||||
; to after null-termination.
|
||||
compSkip:
|
||||
call HLPointsNUMBER
|
||||
jr z, .isNum
|
||||
jr z, .isNumOrBranch
|
||||
call HLPointsBRANCH
|
||||
jr z, .isNumOrBranch
|
||||
call HLPointsLIT
|
||||
jr nz, .isWord
|
||||
; We have a literal
|
||||
@ -93,7 +109,7 @@ compSkip:
|
||||
call strskip
|
||||
inc hl ; byte after word termination
|
||||
ret
|
||||
.isNum:
|
||||
.isNumOrBranch:
|
||||
; skip by 4
|
||||
inc hl \ inc hl
|
||||
; continue to isWord
|
||||
@ -160,7 +176,11 @@ readLIT:
|
||||
; it's a word.
|
||||
call HLPointsNUMBER
|
||||
jr z, .notWord
|
||||
call HLPointsEXITQUIT
|
||||
call HLPointsBRANCH
|
||||
jr z, .notWord
|
||||
call HLPointsEXIT
|
||||
jr z, .notWord
|
||||
call HLPointsQUIT
|
||||
jr z, .notWord
|
||||
; Not a number, then it's a word. Copy word to pad and point to it.
|
||||
push hl ; --> lvl 1. we need it to set DE later
|
||||
|
Loading…
Reference in New Issue
Block a user