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#define	Bxx	BE
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	TEXT	memcmp(SB), $0
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/*
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 * performance:
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 *	(tba)
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 */
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MOVW	R7, 0(FP)
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	MOVW	n+8(FP), R9		/* R9 is count */
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	MOVW	s1+0(FP), R10		/* R10 is pointer1 */
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	MOVW	s2+4(FP), R11		/* R11 is pointer2 */
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	ADD	R9,R10, R12		/* R12 is end pointer1 */
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/*
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 * if not at least 4 chars,
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 * dont even mess around.
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 * 3 chars to guarantee any
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 * rounding up to a word
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 * boundary and 4 characters
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 * to get at least maybe one
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 * full word cmp.
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 */
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	SUBCC	$4,R9, R0
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	BL	out
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/*
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 * test if both pointers
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 * are similarly word alligned
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 */
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	XOR	R10,R11, R7
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	ANDCC	$3,R7, R0
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	BNE	out
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/*
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 * byte at a time to word allign
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 */
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l1:
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	ANDCC	$3,R10, R0
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	BE	l2
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	MOVB	0(R10), R16
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	MOVB	0(R11), R17
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	ADD	$1, R10
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	SUBCC	R16,R17, R0
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	BNE	ne
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	ADD	$1, R11
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	JMP	l1
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/*
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 * turn R9 into end pointer1-15
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 * cmp 16 at a time while theres room
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 */
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l2:
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	SUB	$15,R12, R9
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l3:
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	SUBCC	R10,R9, R0
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	BLEU	l4
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	MOVW	0(R10), R16
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	MOVW	0(R11), R17
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	MOVW	4(R10), R18
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	SUBCC	R16,R17, R0
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	BNE	ne
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	MOVW	4(R11), R19
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	MOVW	8(R10), R16
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	SUBCC	R18,R19, R0
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	BNE	ne
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	MOVW	8(R11), R17
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	MOVW	12(R10), R18
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	SUBCC	R16,R17, R0
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	BNE	ne
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	MOVW	12(R11), R19
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	ADD	$16, R10
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	SUBCC	R18,R19, R0
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	BNE	ne
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	SUBCC	R16,R17, R0
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	BNE	ne
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	ADD	$16, R11
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	JMP	l3
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/*
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 * turn R9 into end pointer1-3
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 * cmp 4 at a time while theres room
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 */
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l4:
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	SUB	$3,R12, R9
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l5:
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	SUBCC	R10,R9, R0
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	BLEU	out
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	MOVW	0(R10), R16
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	MOVW	0(R11), R17
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	ADD	$4, R10
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	SUBCC	R16,R17, R0		/* only works because big endian */
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	BNE	ne
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	ADD	$4, R11
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	JMP	l5
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/*
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 * last loop, cmp byte at a time
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 */
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out:
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	SUBCC	R10,R12, R0
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	BE	zero
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	MOVB	0(R10), R16
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	MOVB	0(R11), R17
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	ADD	$1, R10
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	SUBCC	R16,R17, R0
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	BNE	ne
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	ADD	$1, R11
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	JMP	out
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ne:
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	BG	plus
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	MOVW	$1, R7
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	RETURN
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plus:
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	MOVW	$-1, R7
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	RETURN
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zero:
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	MOVW	R0, R7
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	RETURN