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Rev Author Line No. Line
2 - 1 
	TEXT	memcmp(SB), $0
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MOVW R1, 0(FP)
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4 
/*
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 * performance:
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 *	alligned about 1.0us/call and 17.4mb/sec
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 *	unalligned is about 3.1mb/sec
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 */
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	MOVW	n+8(FP), R3		/* R3 is count */
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	MOVW	s1+0(FP), R4		/* R4 is pointer1 */
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	MOVW	s2+4(FP), R5		/* R5 is pointer2 */
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	ADDU	R3,R4, R6		/* R6 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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	SGT	$4,R3, R1
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	BNE	R1, 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	R4,R5, R1
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	AND	$3, R1
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	BNE	R1, 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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	AND	$3,R4, R1
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	BEQ	R1, l2
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	MOVBU	0(R4), R8
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	MOVBU	0(R5), R9
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	ADDU	$1, R4
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	BNE	R8,R9, ne
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	ADDU	$1, R5
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	JMP	l1
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/*
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 * turn R3 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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	ADDU	$-15,R6, R3
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l3:
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	SGTU	R3,R4, R1
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	BEQ	R1, l4
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	MOVW	0(R4), R8
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	MOVW	0(R5), R9
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	MOVW	4(R4), R10
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	BNE	R8,R9, ne
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	MOVW	4(R5), R11
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	MOVW	8(R4), R8
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	BNE	R10,R11, ne1
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	MOVW	8(R5), R9
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	MOVW	12(R4), R10
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	BNE	R8,R9, ne
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	MOVW	12(R5), R11
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	ADDU	$16, R4
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	BNE	R10,R11, ne1
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	BNE	R8,R9, ne
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	ADDU	$16, R5
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	JMP	l3
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/*
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 * turn R3 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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	ADDU	$-3,R6, R3
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l5:
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	SGTU	R3,R4, R1
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	BEQ	R1, out
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	MOVW	0(R4), R8
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	MOVW	0(R5), R9
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	ADDU	$4, R4
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	BNE	R8,R9, ne	/* only works because big endian */
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	ADDU	$4, R5
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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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	SGTU	R6,R4, R1
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	BEQ	R1, ret
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	MOVBU	0(R4), R8
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	MOVBU	0(R5), R9
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	ADDU	$1, R4
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	BNE	R8,R9, ne
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	ADDU	$1, R5
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	JMP	out
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103 
ne1:
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	SGTU	R10,R11, R1
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	BNE	R1, ret
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	MOVW	$-1,R1
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	RET
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ne:
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	SGTU	R8,R9, R1
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	BNE	R1, ret
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	MOVW	$-1,R1
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ret:
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	RET
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	END