[llvm] [VP][EVL] Support select instruction with EVL-vectorization (PR #109614)

[via llvm-commits]

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@@ -1116,9 +1116,8 @@ void VPWidenSelectEVLRecipe::execute(VPTransformState &State) {
   auto *InvarCond =
       isInvariantCond() ? State.get(getCond(), VPIteration(0, 0)) : nullptr;
 
+  // FIXME: Do we have a scenario where cond is a scalar?
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LiqinWeng wrote:

I agree with you. I tried to construct a test case from C that would satisfy this, but it didn't sucess, so I added an assertion. 

https://github.com/llvm/llvm-project/pull/109614