[clang] [LifetimeSafety] Add missing origins stats for lifetime analysis (PR #166568)

[via cfe-commits]

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@@ -39,6 +46,17 @@ OriginID OriginManager::get(const Expr &E) {
   auto It = ExprToOriginID.find(&E);
   if (It != ExprToOriginID.end())
     return It->second;
+
+  // if the expression has no specific origin, increment the missing origin
+  // counter.
+  std::string ExprStr(E.getStmtClassName());
+  ExprStr = ExprStr + "<" + E.getType().getAsString() + ">";
+  auto CountIt = ExprTypeToMissingOriginCount.find(ExprStr);
+  if (CountIt == ExprTypeToMissingOriginCount.end()) {
+    ExprTypeToMissingOriginCount[ExprStr] = 1;
+  } else {
+    CountIt->second++;
+  }
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DEBADRIBASAK wrote:

Thank you for the feedback. I will incorporate the changes. But I have one query regarding this statement:

> We do this collection at the end of the analysis

Currently we create the origin if it is not available in the map inside `OriginMgr`. If we perform the missing origin count at the end of the analysis it will never show any missing origin.


https://github.com/llvm/llvm-project/pull/166568