[llvm] [DomTree] Reduce number of hash table lookups (NFC) (PR #73097)

[Nikita Popov via llvm-commits]

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@@ -304,8 +306,7 @@ struct SemiNCAInfo {
     // Note that the parents were stored in IDoms and later got invalidated
     // during path compression in Eval.
     for (unsigned i = 2; i < NextDFSNum; ++i) {
-      const NodePtr W = NumToNode[i];
-      auto &WInfo = NodeToInfo[W];
+      auto &WInfo = *NumToInfo[i];
       const unsigned SDomNum = NodeToInfo[NumToNode[WInfo.Semi]].DFSNum;
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nikic wrote:

I've put up a potential fix for this issue at https://github.com/llvm/llvm-project/pull/73148.

https://github.com/llvm/llvm-project/pull/73097