* Wall Street now switches back to earnings season, with two of its so-called "Magnificent Seven" megacap firms - Alphabet and Tesla - reporting after the bell on Wednesday. The performance of the former, in particular, will test the durability of the artificial intelligence theme that's still having profound effects on the whole economy.

But more big tests loom with trade talks still continuing between the Trump administration and counterparts in China and the European Union.

Global shares have rallied, with Tokyo's benchmark Nikkei 225 index finishing 3.5% higher after Japan and the U.S. announced a deal on President Donald Trump's tariffs.