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cut one byte

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This commit is contained in:
Peter Ferrie 2020-01-07 16:57:49 -08:00
parent 925e435e53
commit 22e2f80ae7
1 changed files with 5 additions and 4 deletions
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9
asm/6502/decompress_faster_v2.asm
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@ -10,7 +10,7 @@
; Optional code is presented for two minor 6502 optimizations that break ; Optional code is presented for two minor 6502 optimizations that break
; compatibility with the current LZSA2 format standard. ; compatibility with the current LZSA2 format standard.
; ;
; The code is 241 bytes for the small version, and 268 bytes for the normal. ; The code is 241 bytes for the small version, and 267 bytes for the normal.
; ;
; Copyright John Brandwood 2019. ; Copyright John Brandwood 2019.
; ;
@ -399,8 +399,8 @@ lzsa2_unpack: ldy #0 ; Initialize source index.
cpx #$00 ; X=$FF for a 5-bit offset. cpx #$00 ; X=$FF for a 5-bit offset.
bne .set_offset bne .set_offset
sbc #2 ; Subtract 512 because 13-bit sbc #2 ; Subtract 512 because 13-bit
tax ; offset starts at $FE00. ; offset starts at $FE00.
bne .get_low8 ; Always NZ from previous TAX. bne .get_low8x ; Always NZ from previous SBC.
.get_9_bits: dex ; X=$FF if CS, X=$FE if CC. .get_9_bits: dex ; X=$FF if CS, X=$FE if CC.
asl asl
@ -422,7 +422,8 @@ lzsa2_unpack: ldy #0 ; Initialize source index.
; ;
.get_16_bits: jsr lzsa2_get_byte ; Get hi-byte of offset. .get_16_bits: jsr lzsa2_get_byte ; Get hi-byte of offset.
tax
.get_low8x: tax
.get_low8: .get_low8:
!if (LZSA_FROM_BANK | LZSA_NO_INLINE | LZSA_USE_FFFF) { !if (LZSA_FROM_BANK | LZSA_NO_INLINE | LZSA_USE_FFFF) {