[clang] [LifetimeSafety] Detect use of a reference type as a use of underlying origin (PR #184295)

[Gábor Horváth via cfe-commits]

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@@ -751,9 +757,13 @@ void FactsGenerator::handleUse(const Expr *E) {
   }
 }
 
-void FactsGenerator::markUseAsWrite(const DeclRefExpr *DRE) {
-  if (UseFacts.contains(DRE))
+void FactsGenerator::markUseAsWrite(const DeclRefExpr *DRE,
+                                    bool IsReferenceWrite) {
+  if (UseFacts.contains(DRE)) {
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Xazax-hun wrote:

I know this is in existing code, but we have multiple consecutive lookups of `DRE`. I think we should use `find` and an iterator to avoid the double lookup. 

https://github.com/llvm/llvm-project/pull/184295