[llvm] [VPlan] Remove VPPredInstPHIRecipe::useScalars (PR #143798)

[Luke Lau via llvm-commits]

https://github.com/lukel97 created https://github.com/llvm/llvm-project/pull/143798

It uses the vector value of its operand if possible. Use the default definition in VPUser, which is false since onlyFirstLaneUsed is false.

>From the discussion at https://github.com/llvm/llvm-project/pull/142594#discussion_r2140339682


>From 6df4b2851a2576a6113f1762ef4f54eb357cc699 Mon Sep 17 00:00:00 2001
From: Luke Lau <luke at igalia.com>
Date: Wed, 11 Jun 2025 16:31:45 +0200
Subject: [PATCH] [VPlan] Remove VPPredInstPHIRecipe::useScalars

It uses the vector value of its operand if possible. Use the default definition in VPUser, which is false since onlyFirstLaneUsed is false.

>From the discussion at https://github.com/llvm/llvm-project/pull/142594#discussion_r2140339682
---
 llvm/lib/Transforms/Vectorize/VPlan.h | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/llvm/lib/Transforms/Vectorize/VPlan.h b/llvm/lib/Transforms/Vectorize/VPlan.h
index bbcbfee4e471b..5b8a80d5bbd21 100644
--- a/llvm/lib/Transforms/Vectorize/VPlan.h
+++ b/llvm/lib/Transforms/Vectorize/VPlan.h
@@ -2951,13 +2951,6 @@ class VPPredInstPHIRecipe : public VPSingleDefRecipe {
   void print(raw_ostream &O, const Twine &Indent,
              VPSlotTracker &SlotTracker) const override;
 #endif
-
-  /// Returns true if the recipe uses scalars of operand \p Op.
-  bool usesScalars(const VPValue *Op) const override {
-    assert(is_contained(operands(), Op) &&
-           "Op must be an operand of the recipe");
-    return true;
-  }
 };
 
 /// A common base class for widening memory operations. An optional mask can be