UNtil 2009 to 2016 AMD was free to use any fab as long as GloFo still has something to do. In 2016, AMD had to pay GloFo to NOT use them for some node sizes.

AMD used TSMC for their CPUs (not IO die!) at least for one generation, and TSMC actually dropped the ball that time and AMD went back to GloFo.

Once again, AMD was fabless since 2009 it's a fact, and it's also a fact that it didn't help them at all.