kolibrios/programs/fs/unzip60/qdos/crc68.s

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;===========================================================================
; Copyright (c) 1990-2000 Info-ZIP. All rights reserved.
;
; See the accompanying file LICENSE, version 2000-Apr-09 or later
; (the contents of which are also included in zip.h) for terms of use.
; If, for some reason, all these files are missing, the Info-ZIP license
; also may be found at: ftp://ftp.info-zip.org/pub/infozip/license.html
;===========================================================================
.text
.globl _crc32 ; (ulg val, uch *buf, extent bufsize)
.globl _get_crc_table ; ulg *get_crc_table(void)
_crc32:
move.l 8(sp),d0
bne valid
moveq #0,d0
rts
valid: movem.l d2/d3,-(sp)
jsr _get_crc_table
move.l d0,a0
move.l 12(sp),d0
move.l 16(sp),a1
move.l 20(sp),d1
not.l d0
move.l d1,d2
lsr.l #3,d1
bra decr8
loop8: moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
decr8: dbra d1,loop8
and.w #7,d2
bra decr1
loop1: moveq #0,d3
move.b (a1)+,d3
eor.b d0,d3
lsl.w #2,d3
move.l 0(a0,d3.w),d3
lsr.l #8,d0
eor.l d3,d0
decr1: dbra d2,loop1
done: movem.l (sp)+,d2/d3
not.l d0
rts