[llvm] [CodeGen] Avoid repeated hash lookups (NFC) (PR #123447)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/123447

None

>From 7980b85a4a29b9915f758e2bb0c9a6f95b539880 Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Fri, 17 Jan 2025 09:25:50 -0800
Subject: [PATCH] [CodeGen] Avoid repeated hash lookups (NFC)

---
 llvm/lib/CodeGen/MachineSink.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/CodeGen/MachineSink.cpp b/llvm/lib/CodeGen/MachineSink.cpp
index 3c816f97650901..03d93cecaa5963 100644
--- a/llvm/lib/CodeGen/MachineSink.cpp
+++ b/llvm/lib/CodeGen/MachineSink.cpp
@@ -1784,11 +1784,12 @@ bool MachineSinking::SinkInstruction(MachineInstr &MI, bool &SawStore,
   for (auto &MO : MI.all_defs()) {
     if (!MO.getReg().isVirtual())
       continue;
-    if (!SeenDbgUsers.count(MO.getReg()))
+    auto It = SeenDbgUsers.find(MO.getReg());
+    if (It == SeenDbgUsers.end())
       continue;
 
     // Sink any users that don't pass any other DBG_VALUEs for this variable.
-    auto &Users = SeenDbgUsers[MO.getReg()];
+    auto &Users = It->second;
     for (auto &User : Users) {
       MachineInstr *DbgMI = User.getPointer();
       if (User.getInt()) {