By Noel Randewich and Johann M Cherian (Reuters) -The S&P 500 posted a record high close on Friday for the first time in two years, fueled by a rally in chipmakers and other heavyweight technology stocks on optimism around artificial intelligence. The benchmark’s close confirmed that the S&P 500 has been in a bull market since it closed at its low on Oct. 12, 2022, according to one measure which also puts that date as the end of a bear market. In a selloff between its record high close of 4,796.56 on Jan. 3, 2022 and its low in October 2022, the S&P 500 tumbled 25%. On Friday, the S&P 500 jump…