[llvm] Hint for branch likelihood (PR #67972)

[Nikita Popov via llvm-commits]

nikic wrote:

Not seeing a difference in `instructions:u` with this change: http://llvm-compile-time-tracker.com/compare.php?from=3b25407d977d9ed3dbcaccd4f8850b65e95d70fd&to=8f5c0fd7348e78aedafcee3f7e67f04e3bc79e9c&stat=instructions:u Which is not really surprising -- it might make a difference in cycles, but not at a level I can resolve accurately.

https://github.com/llvm/llvm-project/pull/67972