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

[Gábor Horváth via cfe-commits]

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@@ -68,11 +70,22 @@ void LifetimeSafetyAnalysis::run() {
 
   runLifetimeChecker(*LoanPropagation, *LiveOrigins, FactMgr, AC, Reporter);
 }
+
+void collectLifetimeStats(AnalysisDeclContext &AC, OriginManager &OM,
+                          LifetimeSafetyStats &Stats) {
+  if (!AC.getBody())
+    return;
+  Stmt *FunctionBody = AC.getBody();
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Xazax-hun wrote:

Nit: You could hoist this to before the early return and check `FunctionBody` for nullness.

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