All three indexes ended in positive territory, with the tech-heavy Nasdaq enjoying a healthy boost from chip stocks after Qualcomm reported quarterly sales and profit above analyst expectations.

Markets continued to parse Fed Chair Jerome Powell's assurances on Wednesday that the central bank's next policy move will be to lower its key policy rate, after it left rates unchanged at the end of its monthly meeting. However, he noted that recent strong inflation readings have suggested that first of these rate cuts could be a long time in coming.

"The takeaway from yesterday is that the Fed's bias is still a downward, hold steady or cut rates," said Paul Nolte, senior wealth advisor and market strategist at Murphy & Silvest in Elmhurst, Illinois.

"They're not willing to raise rates from here. They'll keep rates steady, and any sign of economic weakness or lower inflation, they are going to be ready to jump on it and cut."

Data released on Thursday included muted jobless claims, a drop in planned layoffs, a surge in quarterly labor costs and a sharp deceleration in productivity, all of which throws focus on Friday's closely watched April employment report.

"The Fed has been consistent in saying they're going to be data dependent," said Joseph Sroka, chief investment officer at NovaPoint in Atlanta. "We went into this year thinking there could be more cuts, earlier. "The data hasn't supported that."

The Organization for Economic Cooperation and Development (OECD) upgraded its global growth outlook, thanks in part to the U.S. economy's resilience.

First-quarter earnings season has rounded the corner, with 373 of the companies in the S&P 500 having reported. Of those, 77% have posted better-than-expected results, according to LSEG data.

"The common theme (this quarter) is those companies that are beating expectations aren't really being rewarded as much as they have in prior quarters," Nolte added. "And those that are missing expectations are getting shellacked."

Among individual stocks, Qualcomm advanced following its earnings beat.

Shares of used car platform Carvana surged on its upbeat profit forecast.

But disappointing profit guidance sent DoorDash's stock lower.

Etsy shares slid after the online marketplace missed Wall Street expectations for first-quarter gross merchandise sales and profit.

Peloton dropped after the company's CEO stepped down and the company announced a 15% cut to its global workforce.

Apple Inc's shares rose ahead of its quarterly results, which are expected shortly.

According to preliminary data, the S&P 500 gained 46.97 points, or 0.94%, to end at 5,065.36 points, while the Nasdaq Composite gained 238.54 points, or 1.53%, to 15,844.02. The Dow Jones Industrial Average rose 322.37 points, or 0.88%, to 38,225.66.