Major indexes open broadly higher; GameStop, AMC crumble

Major indexes are opening broadly higher, while GameStop and other stocks that have been on wild swings recently turned sharply lower. The S&P 500 added 1.2% in the early going Tuesday, building to its gains from a day earlier. GameStop sank 40% in the early going in its latest bout of extreme volatility, and AMC Entertainment fell nearly as much. Big Tech companies were among the earlier winners, as were several energy companies including Exxon Mobil and Marathon Petroleum, both of which re