Stocks were mixed Tuesday morning, with investors awaiting more corporate earnings results from major companies and a Federal Reserve monetary policy decision on Wednesday.

The S&P 500 ticked up, extending gains after the blue-chip index rose to an all-time high during Monday's regular trading day. The Dow slipped, while the Nasdaq gained. Shares of Tesla (TSLA) fell after the company's first-quarter sales results missed estimates, though earnings and automobile gross margins exceeded expectations in the report delivered Monday evening.

Earnings results will pick up on Tuesday with companies including Microsoft (MSFT), Alphabet (GOOGL) and Starbucks (SBUX) poised to report results. The Big Tech names reporting Tuesday and later this week especially are set to be closely watched, with these stocks having largely underperformed against the broader market for the year-to-date as 2020's tech and growth-led rally cooled and investors turned instead to cyclical and value shares.

"Except for Google, you get the FAANG stocks, and they've been dead money for 7, 8, 9 months now," Matt Maley, managing director and chief market strategist at Miller Tabak, told Yahoo Finance on Monday. "We're seeing Facebook trying to break out, Amazon finally trying to get to the top end of its range, Netflix last week couldn't break out, so that was a disappointment. So if those things could finally pick up, that would be positive [for stocks]."