[llvm] [CSSPGO] Compute and report profile matching recovered callsites and samples (PR #79090)

[via llvm-commits]

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@@ -444,15 +444,36 @@ class SampleProfileMatcher {
   // the profile.
   StringMap<LocToLocMap> FuncMappings;
 
-  // Profile mismatching statstics.
+  // Match state for an anchor/callsite.
+  enum class MatchState {
+    InitialMatch = 0,
+    InitialMismatch = 1,
+    // From initial mismatch to final match.
+    RecoveredMismatch = 2,
+    // From initial match to final mismatch.
+    RemovedMatch = 3,
+    Unknown = 32,
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WenleiHe wrote:

Usually we use 0 as uninitialized/unknown value. This is because for zero initialized memory, this naturally sets everything to unknown. 

https://github.com/llvm/llvm-project/pull/79090