We had two threads on this topic just a few weeks ago.
Aside from what you mentioned, "xla" could equally well refer to Xbox Live Arcade. Tagging a question that way probably isn't helpful, but I can definitely imagine game developers with a programming question wanting to do so.
We should not keep tags this short unless they are really definitely unambiguous - in particular, programming language names like c
, c#
, c++
, css
(I'm going to call that a programming language for these purposes, because there's a set of rules that constrain the text a programmer writes, and it's interpreted in accordance with those rules to do something interesting).
For the Excel questions, we could use a name like excel-xla, sure, but I think excel-addin is clearer and avoids redundancy. For TensorFlow stuff, the existing tensorflow-xla is fine, and follows established conventions.
The purpose of tags is to categorize for filtering - not to provide search keywords. If it's ambiguous, it isn't effectively categorizing.
If "XLA" referred to a compiler that weren't associated with TensorFlow or something else with similar categorizing power, we might use something like xla-compiler. And yes: IMO, if we ever discover something new that's worth asking programming questions about and is reasonably called "GCC", then existing gcc questions should move to gcc-compiler. (c-gcc just seems way too awkward.)