[llvm] [Transforms] Avoid repeated hash looksup (NFC) (PR #107727)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/107727

None

>From 64bcebd8a42021a2b3e1b430bb512cb51b6794e9 Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Sat, 7 Sep 2024 11:35:36 -0700
Subject: [PATCH] [Transforms] Avoid repeated hash looksup (NFC)

---
 llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp b/llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp
index c7b88d3c48a69f..2c2400d9dd7a82 100644
--- a/llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp
+++ b/llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp
@@ -139,11 +139,9 @@ static bool processHeaderPhiOperands(BasicBlock *Header, BasicBlock *Latch,
   SmallPtrSet<Instruction *, 8> VisitedInstr;
 
   std::function<bool(Instruction * I)> ProcessInstr = [&](Instruction *I) {
-    if (VisitedInstr.count(I))
+    if (!VisitedInstr.insert(I).second)
       return true;
 
-    VisitedInstr.insert(I);
-
     if (AftBlocks.count(I->getParent()))
       for (auto &U : I->operands())
         if (Instruction *II = dyn_cast<Instruction>(U))