* UNPACK source for SPACKERv3	(C)THE FIREHAWKS'92
* -------------------------------------------------
* in	a0: even address start packed block
* out	d0: original length or 0 if not SPv3 packed
* =================================================

	.EXPORT	u_sp3


u_sp3:	
	moveq	#0,d0
	movem.l	d0-a6,-(sp)
	lea		sp3_53(pc),a6
	movea.l	a0,a1
	cmpi.l	#'SPv3',(a1)+
	bne.s	sp3_02
	tst.w	(a1)
	bne.s	sp3_02
	move.l	(a1)+,d5
	move.l	(a1)+,d0
	move.l	(a1)+,(sp)
	movea.l	a0,a2
	adda.l	d0,a0
	move.l	-(a0),-(a1)
	move.l	-(a0),-(a1)
	move.l	-(a0),-(a1)
	move.l	-(a0),-(a1)
	adda.l	(sp),a1
	lea		sp3_58-sp3_53(a6),a3
	moveq	#128-1,d0

sp3_01:	
	move.l	(a2)+,(a3)+
	dbf		d0,sp3_01
	suba.l	a2,a3
	move.l	a3,-(sp)
	bsr.s	sp3_03
	bsr		sp3_21
	move.b	-(a0),d0
	adda.l	(sp)+,a0
	move.b	d0,(a0)+
	lea		sp3_58-sp3_53(a6),a2
	bsr		sp3_22
	bsr		sp3_15

sp3_02:	
	movem.l	(sp)+,d0-a6
	rts

sp3_03:	
	;move.w	SR,d1
	;andi.w	#$2000,d1
	;beq.s	sp3_04
	;move.w	$FFFF8240.W,2(a6)
	;btst	#1,$FFFF8260.W
	;bne.s	sp3_04
	;swap	d5

sp3_04:	
	clr.w	d5
	move.w	-(a0),d6
	lea		sp3_54-sp3_53(a6),a3
	move.b	d6,(a3)+
	moveq	#1,d3
	moveq	#6,d4

sp3_05:	
	cmp.b	d6,d3
	bne.s	sp3_06
	addq.w	#2,d3

sp3_06:	
	move.b	d3,(a3)+
	addq.w	#2,d3
	dbf		d4,sp3_05
	moveq	#$10,d4
	move.b	-(a0),(a3)+
	move.b	d4,(a3)+
	move.b	-(a0),(a3)+
	move.b	d4,(a3)+
	move.b	-(a0),d4
	move.w	d4,(a6)
	lea		sp3_57-sp3_53(a6),a5
	move.b	-(a0),d4
	lea		1(a5,d4.w),a3

sp3_07:	
	move.b	-(a0),-(a3)
	dbf		d4,sp3_07
	move.b	-(a0),-(a3)
	beq.s	sp3_08
	suba.w	d4,a0

sp3_08:	
	moveq	#0,d2
	move.b	-(a0),d2
	move.w	d2,d3
	move.b	-(a0),d7

sp3_09:	
	bsr.s	sp3_10
	bsr.s	sp3_10
	dbf		d2,sp3_09
	rts

sp3_10:	
	not.w	d4
	add.b	d7,d7
	bne.s	sp3_11
	move.b	-(a0),d7
	addx.b	d7,d7

sp3_11:	
	bcs.s	sp3_12
	move.w	d2,d0
	subq.w	#1,d3
	sub.w	d3,d0
	add.w	d0,d0
	add.w	d4,d0
	add.w	d0,d0
	neg.w	d0
	move.w	d0,-(a3)
	rts

sp3_12:	
	moveq	#2,d1
	bsr		sp3_44
	add.w	d0,d0
	beq.s	sp3_13
	move.b	d0,-(a3)
	moveq	#2,d1
	bsr		sp3_44
	add.w	d0,d0
	move.b	d0,-(a3)
	rts

sp3_13:	
	moveq	#2,d1
	bsr		sp3_44
	move.w	sp3_55-sp3_53(a6),d1
	add.w	d0,d0
	beq.s	sp3_14
	move.w	sp3_55+2-sp3_53(a6),d1

sp3_14:	
	or.w	d1,d0
	move.w	d0,-(a3)
	rts

sp3_15:	
	;move.w	SR,d1
	;andi.w	#$2000,d1
	;beq.s	sp3_16
	;move.w	2(a6),$FFFF8240.W

sp3_16:	
	tst.w	d6
	bpl.s	sp3_20
	movea.l	a1,a2
	movea.l	a1,a3
	adda.l	4(sp),a3

sp3_17:	
	moveq	#3,d6

sp3_18:	
	move.w	(a2)+,d0
	moveq	#3,d5

sp3_19:	
	add.w	d0,d0
	addx.w	d1,d1
	add.w	d0,d0
	addx.w	d2,d2
	add.w	d0,d0
	addx.w	d3,d3
	add.w	d0,d0
	addx.w	d4,d4
	dbf		d5,sp3_19
	dbf		d6,sp3_18
	cmpa.l	a2,a3
	blt.s	sp3_20
	movem.w	d1-d4,-8(a2)
	cmpa.l	a2,a3
	bne.s	sp3_17

sp3_20:	
	rts

sp3_21:	
	move.b	-(a0),-(a1)

sp3_22:	
	swap	d5
	beq.s	sp3_23
	;move.w	d5,$FFFF8240.W

sp3_23:	
	lea	sp3_56+2-sp3_53(a6),a3
	cmpa.l	a0,a2
	blt.s	sp3_25
	rts

sp3_24:	
	adda.w	d3,a3

sp3_25:	
	add.b	d7,d7
	bcc.s	sp3_28
	beq.s	sp3_27

sp3_26:	
	move.w	(a3),d3
	bmi.s	sp3_24
	bra.s	sp3_29

sp3_27:	
	move.b	-(a0),d7
	addx.b	d7,d7
	bcs.s	sp3_26

sp3_28:	
	move.w	-(a3),d3
	bmi.s	sp3_24

sp3_29:	
	ext.w	d3
	jmp		sp3_30(pc,d3.w)

sp3_30:	
	bra.s	sp3_30
	bra.s	sp3_41
	bra.s	sp3_41
	bra.s	sp3_41
	bra.s	sp3_41
	bra.s	sp3_41
	bra.s	sp3_37
	bra.s	sp3_36
	bra.s	sp3_32
	bra.s	sp3_33
	bra.s	sp3_31
	bra.s	sp3_34
	bra.s	sp3_21

sp3_31:	
	move.b	(a5),-(a1)
	bra.s	sp3_22

sp3_32:	
	bsr.s	sp3_43
	move.b	1(a5,d0.w),-(a1)
	bra.s	sp3_22

sp3_33:	
	bsr.s	sp3_43
	add.w	(a6),d0
	move.b	1(a5,d0.w),-(a1)
	bra.s	sp3_22

sp3_34:	
	moveq	#3,d1
	bsr.s	sp3_44
	lsr.w	#1,d0
	bcc.s	sp3_35
	not.w	d0

sp3_35:	
	move.b	(a1),d1
	add.w	d0,d1
	move.b	d1,-(a1)
	bra.s	sp3_22

sp3_36:	
	lea		sp3_52-2-sp3_53(a6),a4
	bsr.s	sp3_48
	addi.w	#16,d0
	lea		1(a1,d0.w),a3
	move.b	-(a3),-(a1)
	move.b	-(a3),-(a1)
	bra		sp3_22

sp3_37:	
	moveq	#3,d1
	bsr.s	sp3_44
	tst.w	d0
	beq.s	sp3_38
	addq.w	#5,d0
	bra.s	sp3_40

sp3_38:	
	move.b	-(a0),d0
	beq.s	sp3_39
	addi.w	#20,d0
	bra.s	sp3_40

sp3_39:	
	moveq	#13,d1
	bsr.s	sp3_44
	addi.w	#276,d0

sp3_40:	
	move.w	d0,d3
	add.w	d3,d3

sp3_41:	
	lea		sp3_52-sp3_53(a6),a4
	bsr.s	sp3_48
	lsr.w	#1,d3
	lea		1(a1,d0.w),a3
	move.b	-(a3),-(a1)

sp3_42:	
	move.b	-(a3),-(a1)
	dbf		d3,sp3_42
	bra		sp3_22

sp3_43:	
	moveq	#0,d1
	move.b	(a3),d1

sp3_44:	
	moveq	#0,d0
	cmpi.w	#7,d1
	bpl.s	sp3_47

sp3_45:	
	add.b	d7,d7
	beq.s	sp3_46
	addx.w	d0,d0
	dbf	d1,sp3_45
	rts

sp3_46:	
	move.b	-(a0),d7
	addx.b	d7,d7
	addx.w	d0,d0
	dbf		d1,sp3_45
	rts

sp3_47:	
	move.b	-(a0),d0
	subq.w	#8,d1
	bpl.s	sp3_45
	rts

sp3_48:	
	moveq	#0,d1
	move.b	(a3),d1
	adda.w	d1,a4
	move.w	(a4),d1
	bsr.s	sp3_44
	tst.b	d6
	beq.s	sp3_51
	move.w	d0,d4
	andi.w	#$FFF0,d4
	andi.w	#$000F,d0
	beq.s	sp3_50
	lsr.w	#1,d0
	beq.s	sp3_49
	roxr.b	#1,d7
	bcc.s	sp3_50
	move.b	d7,(a0)+
	moveq	#-128,d7
	bra.s	sp3_50

sp3_49:	
	moveq	#2,d1
	bsr.s	sp3_44
	add.w	d0,d0
	or.w	d4,d0
	bra.s	sp3_51

sp3_50:	
	lea		sp3_54-sp3_53(a6),a3
	or.b	(a3,d0.w),d4
	move.w	d4,d0

sp3_51:	
	add.w	18(a4),d0
	rts

		DC.W	3

sp3_52:	DC.W	4,5,7,8,9,10,11,12
		DC.W	-16
		DC.W	0,32,96,352,864,1888,3936,8032

sp3_53:	DS.L	1
sp3_54:	DS.B	8
sp3_55:	DS.W	2*64
sp3_56:	DS.W	2
		DS.B	1
sp3_57:	DS.B	1
		DS.B	2*64
sp3_58:	DS.B	512