diff --git a/asm/z80/unlzsa1_small_v1.asm b/asm/z80/unlzsa1_small_v1.asm deleted file mode 100644 index 806357b..0000000 --- a/asm/z80/unlzsa1_small_v1.asm +++ /dev/null @@ -1,129 +0,0 @@ -; -; Size-optimized LZSA1 decompressor by spke (v.1 23/04/2019-30/07/2019, 67 bytes); -; with improvements by uniabis (30/07/2019, -1 byte, +3% speed). -; -; The data must be compressed using the command line compressor by Emmanuel Marty -; The compression is done as follows: -; -; lzsa.exe -f1 -r -; -; where option -r asks for the generation of raw (frame-less) data. -; -; The decompression is done in the standard way: -; -; ld hl,FirstByteOfCompressedData -; ld de,FirstByteOfMemoryForDecompressedData -; call DecompressLZSA1 -; -; Backward compression is also supported; you can compress files backward using: -; -; lzsa.exe -f1 -r -b -; -; and decompress the resulting files using: -; -; ld hl,LastByteOfCompressedData -; ld de,LastByteOfMemoryForDecompressedData -; call DecompressLZSA1 -; -; (do not forget to uncomment the BACKWARD_DECOMPRESS option in the decompressor). -; -; Of course, LZSA compression algorithms are (c) 2019 Emmanuel Marty, -; see https://github.com/emmanuel-marty/lzsa for more information -; -; Drop me an email if you have any comments/ideas/suggestions: zxintrospec@gmail.com -; -; This software is provided 'as-is', without any express or implied -; warranty. In no event will the authors be held liable for any damages -; arising from the use of this software. -; -; Permission is granted to anyone to use this software for any purpose, -; including commercial applications, and to alter it and redistribute it -; freely, subject to the following restrictions: -; -; 1. The origin of this software must not be misrepresented; you must not -; claim that you wrote the original software. If you use this software -; in a product, an acknowledgment in the product documentation would be -; appreciated but is not required. -; 2. Altered source versions must be plainly marked as such, and must not be -; misrepresented as being the original software. -; 3. This notice may not be removed or altered from any source distribution. - -; DEFINE BACKWARD_DECOMPRESS - - IFNDEF BACKWARD_DECOMPRESS - - MACRO NEXT_HL - inc hl - ENDM - - MACRO ADD_OFFSET - ex de,hl : add hl,de - ENDM - - MACRO BLOCKCOPY - ldir - ENDM - - ELSE - - MACRO NEXT_HL - dec hl - ENDM - - MACRO ADD_OFFSET - push hl : or a : sbc hl,de : pop de ; 11+4+15+10 = 40t / 5 bytes - ENDM - - MACRO BLOCKCOPY - lddr - ENDM - - ENDIF - -@DecompressLZSA1: - ld b,0 - - ; first a byte token "O|LLL|MMMM" is read from the stream, - ; where LLL is the number of literals and MMMM is - ; a length of the match that follows after the literals -ReadToken: ld a,(hl) : NEXT_HL : push af - and #70 : jr z,NoLiterals - - rrca : rrca : rrca : rrca ; LLL<7 means 0..6 literals... - cp #07 : call z,ReadLongBA ; LLL=7 means 7+ literals... - - ld c,a : BLOCKCOPY - - ; next we read the low byte of the -offset -NoLiterals: pop af : push de : ld e,(hl) : NEXT_HL : ld d,#FF - ; the top bit of token is set if - ; the offset contains the high byte as well - or a : jp p,ShortOffset - -LongOffset: ld d,(hl) : NEXT_HL - - ; last but not least, the match length is read -ShortOffset: and #0F : add 3 ; MMMM<15 means match lengths 0+3..14+3 - cp 15+3 : call z,ReadLongBA ; MMMM=15 means lengths 14+3+ - ld c,a - - ex (sp),hl ; BC = len, DE = -offset, HL = dest, SP -> [src] - ADD_OFFSET ; BC = len, DE = dest, HL = dest+(-offset), SP -> [src] - BLOCKCOPY ; BC = 0, DE = dest - pop hl : jr ReadToken ; HL = src - - ; a standard routine to read extended codes - ; into registers B (higher byte) and A (lower byte). -ReadLongBA: add (hl) : NEXT_HL : ret nc - - ; the codes are designed to overflow; - ; the overflow value 1 means read 1 extra byte - ; and overflow value 0 means read 2 extra bytes -.code1: ld b,a : ld a,(hl) : NEXT_HL : ret nz -.code0: ld c,a : ld b,(hl) : NEXT_HL - - ; the two-byte match length equal to zero - ; designates the end-of-data marker - or b : ld a,c : ret nz - pop de : pop de : ret -