[llvm] [NFC][Support] Refactor FormatVariadic code. (PR #106610)

[Rahul Joshi via llvm-commits]

jurahul wrote:

> LG. but some context in the PR description could be welcome (you're saying "what" the patch does, but not always "why": for example why is the change to 32 bits)

SG, I added: "(as 64-bits for this in the context of formatting text seems excessive)" in the commit description. I think we can safely go to 16-bits as well but given that these are short lived objects (though still potentially heap allocated) 32-bits seems like a reasonable middle ground.

https://github.com/llvm/llvm-project/pull/106610