}
	}
	return 0, false
}

// ARM64RegisterShift constructs an ARM64 register with shift operation.
func ARM64RegisterShift(reg, op, count int16) (int64, error) {
	// the base register of shift operations must be general register.
	if reg > arm64.REG_R31 || reg < arm64.REG_R0 {
		return 0, errors.New("invalid register for shift operation")
	}
	return int64(reg&31)<<16 | int64(op)<<22 | int64(uint16(count)), nil
}