[llvm] [CodeGen] Avoid repeated hash lookups (NFC) (PR #128300)

[Kazu Hirata via llvm-commits]

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@@ -1545,24 +1545,21 @@ void HoistSpillHelper::runHoistSpills(
     for (MachineDomTreeNode *Child : (*RIt)->children()) {
       if (!SpillsInSubTreeMap.contains(Child))
         continue;
-      // The stmt "SpillsInSubTree = SpillsInSubTreeMap[*RIt].first" below
+      // The stmt "auto &[...] = SpillsInSubTreeMap[*RIt]" below
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kazutakahirata wrote:

I've restored the variable name.

https://github.com/llvm/llvm-project/pull/128300