This is a very interesting question, I speculate the process must be pretty good, otherwise it probably wouldn’t be used for such large chips.

HiSilicon Ascend 910B measures 21.32 mm × 31.22 mm and has an enlarged die size of 665.61 mm²

Compare that to AMD making the first Ryzen chiplets only 200 mm² on the GloFo 14nm process, to maximize yields, which was a huge advantage in the competition against Intel.