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

[Luke Lau via llvm-commits]

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@@ -340,7 +325,7 @@ for.cond.cleanup28:
 
 for.body29:
   %i24.0170 = phi i16 [ 0, %entry], [ %inc37, %for.body29]
-  %add33 = add i16 undef, %i24.0170
+  %add33 = add i16 3, %i24.0170
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lukel97 wrote:

Looks like this a negative test for a SCEV check, maybe plumb through an argument here just we get the same codepath as the test below?

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