Digital video recording pioneer TiVo and microchip-equipment maker KLA-Tencor on Tuesday became the latest in a growing list Silicon Valley companies to shed jobs. KLA-Tencor said it would cut its workforce by 15 percent, or around 900 jobs, as it moves to weather the economic downturn. TiVo said in a regulatory filing that it will cut an unspecified number of positions in a move to reduce expenses.