[llvm] [Analysis]: Allow inlining recursive call IF recursion depth is 1. (PR #119677)

[David Green via llvm-commits]

https://github.com/davemgreen commented:

Converting recursive functions to non-recursive functions certainly sounds like a nice idea. I guess this is getting stuck because it requires a dom-tree, and it needs to search in some way for the call from the icmp? After looking into it I think the searching is probably OK - looking for the Call that uses the Function and looking up to the ICmp. The alternative of searching down to the recursive call sounds like it might need to search more on average. And the DomTree we already calculate elsewhere during inlining and AFAIU should be fine for compile time so long as it is rare enough.

https://github.com/llvm/llvm-project/pull/119677