[llvm] ValueTracking: strip stray break in recur-match (PR #109794)

[Nikita Popov via llvm-commits]

nikic wrote:

> What strikes me as strange is that the `break` seemed completely unintentional: I dug through the history, and couldn't find any evidence that it was there for some reason.

This kind of break can be there if we expect a code path to be strictly better. Generally speaking, if we can analyze something as a recurrence, the results we get should always be better than a naive analysis, so falling through to the naive analysis is unnecessary.

It's just that the exact way this was done here it is not actually true, because we miss the special handling for conditions on the predecessor branch.

https://github.com/llvm/llvm-project/pull/109794