[llvm] [VPlan] Don't rely on region check in isUniformAfterVectorization. (PR #137883)

[via llvm-commits]

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@@ -39,18 +39,37 @@ const SCEV *getSCEVExprForVPValue(VPValue *V, ScalarEvolution &SE);
 
 /// Returns true if \p VPV is uniform after vectorization.
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ayalz wrote:

Independent: documentation should be (more) meaningful. Name should be more accurate.

https://github.com/llvm/llvm-project/pull/137883