Shares in computer chipmakers slumped Wednesday after Nvidia said tighter U.S. government controls on exports of computer chips used for artificial intelligence will cost it an extra $5.5 billion. The company, which announced Monday that it will produce its artificial intelligence super computers in the United States for the first time, said the government told it that its H20 integrated circuits and others of a similar bandwidth would be subject to the licensing requirements for the “indefinite future.” In a regulatory filing, Nvidia said the government said the controls addressed risks that the products “may be used in or diverted…