[llvm] [BasicBlockSections] Introduce the path cloning profile format to BasicBlockSectionsProfileReader. (PR #67214)

[Sriraman Tallam via llvm-commits]

================
@@ -34,17 +35,36 @@ INITIALIZE_PASS(BasicBlockSectionsProfileReader, "bbsections-profile-reader",
                 "Reads and parses a basic block sections profile.", false,
                 false)
 
+Expected<ProfileBBID>
----------------
tmsri wrote:

Please add a leading comment on what this function parses?

https://github.com/llvm/llvm-project/pull/67214