[llvm] [LV][NFC] Remove undef values in some test cases (PR #164401)

[Luke Lau via llvm-commits]

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@@ -449,7 +411,7 @@ for.cond.cleanup28:
 
 for.body29:
   %i24.0170 = phi i16 [ 0, %entry], [ %inc37, %for.body29]
-  %add33 = add i16 undef, %i24.0170
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lukel97 wrote:

It looks like this removes a SCEV check in the NPGSO check lines even though it was branching on undef. It looks like this was originally testing that we don't assert when emitting a SCEV check, can we preserve that if we plumb through a function argument instead?

https://github.com/llvm/llvm-project/pull/164401