Apple is set to report earnings Tuesday May 2, and analysts at Credit Suisse are advising clients to buy Apple stock ahead of the release.

Shares of Apple have climbed 24% so far this year to $143.69 as of 10:22 ET. In a report circulated to clients April 28, Credit Suisse analyst Kulbinder Garcha reiterated his "Outperform" rating and $170 price target on the stock, implying more than 18% of potential upside.

"That recent data points from the supply chain suggest that overall iPhone shipments remain in line to ahead of expectations, with potential for a stronger mix," he said.

The analyst said that the real reason to buy Apple stock is the pent-up demand for a new iPhone with substantial changes. Garcha said the iPhone 8 is that iPhone, and that a "super cycle" of iPhone upgrading will ensue.

Here's Garcha:

Garcha referred to a March 10 report from Credit Suisse to explain why he believes the iPhone 8 will be a meaningful upgrade. That report said: