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This commit is contained in:
Peter Ferrie 2019-07-10 10:48:15 -07:00
parent f52ba3c40c
commit a1841e5e5d
1 changed files with 2 additions and 5 deletions
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7
asm/6502/decompress_v1.asm
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@ -81,10 +81,7 @@ NO_LITERALS
BMI GET_LONG_OFFSET ; $80: 16 bit offset BMI GET_LONG_OFFSET ; $80: 16 bit offset
JSR GETSRC ; get 8 bit offset from stream in A JSR GETSRC ; get 8 bit offset from stream in A
TAX ; save for later
CLC ; add dest + match offset
ADC PUTDST+1 ; low 8 bits
STA COPY_MATCH_LOOP+1 ; store back reference address
LDA #$0FF ; high 8 bits LDA #$0FF ; high 8 bits
BNE GOT_OFFSET ; go prepare match BNE GOT_OFFSET ; go prepare match
; (*like JMP GOT_OFFSET but shorter) ; (*like JMP GOT_OFFSET but shorter)
@ -117,6 +114,7 @@ GETMATCH_INC_HI
GET_LONG_OFFSET ; handle 16 bit offset: GET_LONG_OFFSET ; handle 16 bit offset:
JSR GETLARGESRC ; grab low 8 bits in X, high 8 bits in A JSR GETLARGESRC ; grab low 8 bits in X, high 8 bits in A
GOT_OFFSET
STA OFFSHI ; store high 8 bits of offset STA OFFSHI ; store high 8 bits of offset
TXA TXA
@ -126,7 +124,6 @@ GET_LONG_OFFSET ; handle 16 bit offset:
OFFSHI = *+1 OFFSHI = *+1
LDA #$AA ; high 8 bits LDA #$AA ; high 8 bits
GOT_OFFSET
ADC PUTDST+2 ADC PUTDST+2
STA COPY_MATCH_LOOP+2 ; store high 8 bits of address STA COPY_MATCH_LOOP+2 ; store high 8 bits of address