[llvm] [LV] Use wide lane masks as the canonical form when tail-folding & interleaving (PR #209484)

[Benjamin Maxwell via llvm-commits]

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@@ -1222,15 +1222,18 @@ class LLVM_ABI_FOR_TEST VPInstruction : public VPRecipeWithIRFlags,
 public:
   /// VPlan opcodes, extending LLVM IR with idiomatics instructions.
   enum {
-    FirstOrderRecurrenceSplice =
-        Instruction::OtherOpsEnd + 1, // Combines the incoming and previous
-                                      // values of a first-order recurrence.
+    FirstOrderRecurrenceSplice = Instruction::OtherOpsEnd +
+        1, // Combines the incoming and previous
+           // values of a first-order recurrence.
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MacDue wrote:

nit: Unrelated change?

https://github.com/llvm/llvm-project/pull/209484