[llvm] [VPlan] Rename onlyFirstLaneUsed (NFC) (PR #166562)

[Luke Lau via llvm-commits]

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@@ -1163,7 +1163,7 @@ class LLVM_ABI_FOR_TEST VPInstruction : public VPRecipeWithIRFlags,
   bool opcodeMayReadOrWriteFromMemory() const;
 
   /// Returns true if the recipe only uses the first lane of operand \p Op.
-  bool onlyFirstLaneUsed(const VPValue *Op) const override;
+  bool usesFirstLaneOnly(const VPValue *Op) const override;
 
   /// Returns true if the recipe only uses the first part of operand \p Op.
   bool onlyFirstPartUsed(const VPValue *Op) const override;
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lukel97 wrote:

Should onlyFirstPartUsed be renamed too for consistency?

https://github.com/llvm/llvm-project/pull/166562