** Shares of U.S. chipmakers climb premarket after world's largest contract chip manufacturer TSMC's bullish forecast for the year on robust demand for AI

** TSMC 2330.TW stands by its annual expectations for sales and capital spending despite U.S. tariffs and forecasts AI chip revenue to double

** U.S.-listed shares of TSMC rise 3.7% premarket; AI chipmakers and TSMC customers Nvidia NVDA.O and AMD AMD.O up more than 1% premarket

** Nvidia and AMD tumbled more than 6% and sparked a global chip stock selloff on Wednesday after flagging hits from latest U.S. curbs on exports to China

** Networking and custom AI chipmakers Marvell Technology MRVL.O and Broadcom AVGO.O and, memory chip firm Micron MU.O up nearly 2%

** Benchmark Philadelphia Semiconductor Index .SOX down ~22.6% YTD after rising ~19.3% last year as uncertainty around tariffs and AI investment cloud sector

(Reporting by Arsheeya Bajwa in Bengaluru)

((ArsheeyaSingh.Bajwa@thomsonreuters.com; +91 8510015800;))