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This commit is contained in:
Peter Ferrie 2019-07-09 18:30:29 -07:00
parent e85cb8a5bb
commit 15c9059adf
1 changed files with 8 additions and 6 deletions
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14
asm/8088/decompress_small_v2.S
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@ -76,15 +76,16 @@ lzsa2_decompress:
; 5 bit offset ; 5 bit offset
cmp dl,020H ; test bit 5 cmp dl,020H ; test bit 5
call .get_nibble_x call .get_nibble_x
dec ah ; set offset bits 15-8 to 1 jmp short .dec_offset_top
jmp short .get_match_length
.offset_9_bit: ; 9 bit offset .offset_9_bit: ; 9 bit offset
lodsb ; get 8 bit offset from stream in A lodsb ; get 8 bit offset from stream in A
dec ah ; set offset bits 15-8 to 1 dec ah ; set offset bits 15-8 to 1
test dl,020H ; test bit Z (offset bit 8) test dl,020H ; test bit Z (offset bit 8)
je .get_match_length je .get_match_length
.dec_offset_top:
dec ah ; clear bit 8 if Z bit is clear dec ah ; clear bit 8 if Z bit is clear
; or set offset bits 15-8 to 1
jmp short .get_match_length jmp short .get_match_length
.rep_match_or_large_offset: .rep_match_or_large_offset:
@ -97,17 +98,18 @@ lzsa2_decompress:
xchg ah,al xchg ah,al
call .get_nibble_x call .get_nibble_x
sub al,2 ; substract 512 sub al,2 ; substract 512
xchg ah,al jmp short .get_match_length_1
lodsb ; load match offset bits 0-7
jmp short .get_match_length
.rep_match_or_16_bit: .rep_match_or_16_bit:
test dl,020H ; test bit Z (offset bit 8) test dl,020H ; test bit Z (offset bit 8)
jne .repeat_match ; rep-match jne .repeat_match ; rep-match
; 16 bit offset ; 16 bit offset
lodsw ; Get 2-byte match offset lodsb ; Get 2-byte match offset
.get_match_length_1:
xchg ah,al xchg ah,al
lodsb ; load match offset bits 0-7
.get_match_length: .get_match_length:
xchg bp,ax ; bp: offset xchg bp,ax ; bp: offset