Stock futures were edging higher on Friday as Treasury yields retreated ahead of the August nonfarm payrolls report.

Artificial-intelligence stocks got a boost as yields fell. Optical networking company Coherent, chip and networking company Marvell, memory supplier Sandisk, and hard-drive maker Seagate rose in the premarket.

Lululemon Athletica was the S&P 500's worst performer ahead of the opening bell, plummeting 19% after the athleticwear company posted disappointing second-quarter earnings and cut its full-year guidance.

Zscaler slid 3.4% after the cybersecurity company reported better-than-expected fourth-quarter earnings and issued strong guidance. Investors may be locking in profit, with shares up 36% the past three months.

Samsara jumped 14% after the software company topped Wall Street's second-quarter earnings target, as annual recurring revenue jumped 30%.

Guidewire Software slumped 15% after software developer beat expectations for the fiscal fourth quarter-but not by enough to stop investors dumping the stock, which has almost doubled since late June.