[llvm] [LV] Strip unnecessary make_{pair, optional} (NFC) (PR #141924)

[Luke Lau via llvm-commits]

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@@ -8491,7 +8486,7 @@ void VPRecipeBuilder::collectScaledReductions(VFRange &Range) {
     PartialReductionChain Chain = Pair.first;
     if (ExtendIsOnlyUsedByPartialReductions(Chain.ExtendA) &&
         ExtendIsOnlyUsedByPartialReductions(Chain.ExtendB))
-      ScaledReductionMap.insert(std::make_pair(Chain.Reduction, Pair.second));
+      ScaledReductionMap.emplace_or_assign(Chain.Reduction, Pair.second);
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lukel97 wrote:

Insert won't overwrite the key if it doesn't exist, but I think emplace_or_assign might? Should this be try_emplace instead? Or just insert with {...}

https://github.com/llvm/llvm-project/pull/141924