[llvm] [VPlan] Use VPInstruction for uniform binops. (PR #141429)

[via llvm-commits]

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@@ -154,6 +154,10 @@ static bool sinkScalarOperands(VPlan &Plan) {
     if (auto *RepR = dyn_cast<VPReplicateRecipe>(SinkCandidate)) {
       if (!ScalarVFOnly && RepR->isSingleScalar())
         continue;
----------------
ayalz wrote:

Could be simplified and generalized to
```suggestion
    if (!isa<VPReplicateRecipe, VPInstruction, VPScalarIVStepsRecipe>(SinkCandidate))
      continue;
    if (!ScalarVFOnly && vputils::isSingleScalar(SinkCandidate))
      continue;
```
?

https://github.com/llvm/llvm-project/pull/141429