[Analysis] Avoid repeated hash lookups (NFC) (#110378)

Author: kazutakahirata

llvm/include/llvm/Analysis/EHUtils.h

@@ -24,10 +24,8 @@ static void computeEHOnlyBlocks(FunctionT &F, DenseSet<BlockT *> &EHBlocks) {
   DenseMap<BlockT *, Status> Statuses;
 
   auto GetStatus = [&](BlockT *BB) {
-    if (Statuses.contains(BB))
-      return Statuses[BB];
-    else
-      return Unknown;
+    auto It = Statuses.find(BB);
+    return It != Statuses.end() ? It->second : Unknown;
   };
 
   auto CheckPredecessors = [&](BlockT *BB, Status Stat) {