for i := 1; i <= len(exitStr); i++ {
		fmt.Fprintf(&exitReStr, "%s$|", exitStr[:i])
	}
	// Finally, match the exit string along with an exit code.
	// This is the only case we use a group, and we'll use this
	// group to extract the numeric code.
	fmt.Fprintf(&exitReStr, "%s([0-9]+)$", exitStr)
	exitRe := regexp.MustCompile(exitReStr.String())

	return &exitCodeFilter{w: w, exitRe: exitRe}, exitStr
}

	MOVW	1(R5), R4		// a4048028
	MOVWU	1(R5), R4		// a404802a
	MOVV	1(R5), R4		// a404c028
	MOVB	1(R5), R4		// a4040028
	MOVBU	1(R5), R4		// a404002a
	MOVWL	1(R5), R4		// a404002e
	MOVVL	1(R5), R4		// a404802e
	LL	1(R5), R4		// a4040020
	LLV	1(R5), R4		// a4040022
	MOVW	$4(R4), R5		// 8510c002
	MOVV	$4(R4), R5		// 8510c002
	MOVW	$-1, R4			// 04fcff02
	MOVV	$-1, R4			// 04fcff02
	MOVW	$1, R4			// 0404c002