[llvm] [SystemZ] Avoid repeated hash lookups (NFC) (PR #126005)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/126005

None

>From 1d8a4901166c89d429e4fcaaefdb8b858d6a7c2e Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Wed, 5 Feb 2025 09:53:33 -0800
Subject: [PATCH] [SystemZ] Avoid repeated hash lookups (NFC)

---
 llvm/lib/Target/SystemZ/SystemZISelLowering.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
index 1fb31c26e20d3c1..a1e02c0c32b61dd 100644
--- a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
@@ -6173,8 +6173,9 @@ SystemZTargetLowering::buildVector(SelectionDAG &DAG, const SDLoc &DL, EVT VT,
     for (unsigned I = 0; I < NumElements; ++I)
       if (isVectorElementLoad(Elems[I])) {
         SDNode *Ld = Elems[I].getNode();
-        UseCounts[Ld]++;
-        if (LoadMaxUses == nullptr || UseCounts[LoadMaxUses] < UseCounts[Ld])
+        auto &Count = UseCounts[Ld];
+        ++Count;
+        if (LoadMaxUses == nullptr || UseCounts[LoadMaxUses] < Count)
           LoadMaxUses = Ld;
       }
     if (LoadMaxUses != nullptr) {