[llvm] [AArch64] Remove special-case inserted shuffle cost. (PR #100537)

[Sjoerd Meijer via llvm-commits]

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@@ -4070,10 +4070,6 @@ InstructionCost AArch64TTIImpl::getShuffleCost(
         Cost += getShuffleCost(NumSources <= 1 ? TTI::SK_PermuteSingleSrc
                                                : TTI::SK_PermuteTwoSrc,
                                NTp, NMask, CostKind, 0, nullptr, Args, CxtI);
-      else if (any_of(enumerate(NMask), [&](const auto &ME) {
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sjoerdmeijer wrote:

Nit: perhaps add the description/explanation why we are not counting already inserted elements to the comment above?

https://github.com/llvm/llvm-project/pull/100537