[clang] [clang] [NFC] explicitly check if ParentMap contains key (PR #121736)

[Sameer Sahasrabuddhe via cfe-commits]

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@@ -34,13 +34,13 @@ static void BuildParentMap(MapTy& M, Stmt* S,
   case Stmt::PseudoObjectExprClass: {
     PseudoObjectExpr *POE = cast<PseudoObjectExpr>(S);
 
-    if (OVMode == OV_Opaque && M[POE->getSyntacticForm()])
+    if (OVMode == OV_Opaque && M.contains(POE->getSyntacticForm()))
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ssahasra wrote:

Fixed with try_emplace() to avoid the second lookup as well, which inserts when the key is already present.

https://github.com/llvm/llvm-project/pull/121736