[llvm] [LV][EVL] Skip tryAddExplicitVectorLength for plans with scalar VF. (PR #125497)

[Florian Hahn via llvm-commits]

================
@@ -8933,14 +8933,15 @@ void LoopVectorizationPlanner::buildVPlansWithVPRecipes(ElementCount MinVF,
   for (ElementCount VF = MinVF; ElementCount::isKnownLT(VF, MaxVFTimes2);) {
     VFRange SubRange = {VF, MaxVFTimes2};
     if (auto Plan = tryToBuildVPlanWithVPRecipes(SubRange)) {
+      bool HasScalarVF = Plan->hasVF(ElementCount::getFixed(1));
----------------
fhahn wrote:

I think there's nothing that completely rules it out at the moment, but I couldn't find a test case, although some of the unit tests did have such plans. I'll look a bit more, but for now probably best to be conservative and keep it as is.

https://github.com/llvm/llvm-project/pull/125497