[llvm] [CodeGen] Avoid repeated hash lookups (NFC) (PR #129190)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/129190

None

>From 62917a2cdcd57ac2a3b97b67abb6fe63a97470a8 Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Thu, 27 Feb 2025 01:50:59 -0800
Subject: [PATCH] [CodeGen] Avoid repeated hash lookups (NFC)

---
 llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp b/llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp
index dbc724629d3be..8d91e7119d0ba 100644
--- a/llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp
+++ b/llvm/lib/CodeGen/AssignmentTrackingAnalysis.cpp
@@ -600,12 +600,12 @@ class MemLocFragmentFill {
         break;
     }
 
-    auto CurrentLiveInEntry = LiveIn.find(&BB);
     // If there's no LiveIn entry for the block yet, add it.
-    if (CurrentLiveInEntry == LiveIn.end()) {
+    auto [CurrentLiveInEntry, Inserted] = LiveIn.try_emplace(&BB);
+    if (Inserted) {
       LLVM_DEBUG(dbgs() << "change=true (first) on meet on " << BB.getName()
                         << "\n");
-      LiveIn[&BB] = std::move(BBLiveIn);
+      CurrentLiveInEntry->second = std::move(BBLiveIn);
       return /*Changed=*/true;
     }