[llvm] [VPlan] Narrow VPWidenGEPRecipe if only its first lane is used. (PR #221171)

[Mel Chen via llvm-commits]

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@@ -0,0 +1,66 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
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Mel-Chen wrote:

d86fc06683059090c23f198c5d6c7029ddb84a65

https://github.com/llvm/llvm-project/pull/221171