[llvm] [LiveDebugValues] Avoid repeated hash lookups (NFC) (PR #110379)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/110379

None

>From 50a66929b8014eb22828daa27adacda01b0b3b74 Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Fri, 27 Sep 2024 08:34:43 -0700
Subject: [PATCH] [LiveDebugValues] Avoid repeated hash lookups (NFC)

---
 llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp b/llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp
index a73a3aa59403b3..a9d28a39c4418b 100644
--- a/llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp
+++ b/llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp
@@ -3958,12 +3958,10 @@ class LDVSSAUpdater {
   /// For a given MBB, create a wrapper block for it. Stores it in the
   /// LDVSSAUpdater block map.
   LDVSSABlock *getSSALDVBlock(MachineBasicBlock *BB) {
-    auto it = BlockMap.find(BB);
-    if (it == BlockMap.end()) {
-      BlockMap[BB] = new LDVSSABlock(*BB, *this);
-      it = BlockMap.find(BB);
-    }
-    return it->second;
+    auto [It, Inserted] = BlockMap.try_emplace(BB);
+    if (Inserted)
+      It->second = new LDVSSABlock(*BB, *this);
+    return It->second;
   }
 
   /// Find the live-in value number for the given block. Looks up the value at