Looking at the die shot, the CPU, GPU, and NPU jumps out, if you've seen a bunch of other die shots before, and combine that with the core counts that Apple ann

Looking at the die shot, the CPU, GPU, and NPU jumps out, if you've seen a bunch of other die shots before, and combine that with the core counts that Apple announced. For less obvious blocks, engineers with the right specialties might be able to make a guess. Otherwise thermal imaging would allow some guesses when running targeted algorithms.