[llvm] [Analysis] Avoid repeated hash lookups (NFC) (PR #126851)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-analysis

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/126851.diff


1 Files Affected:

- (modified) llvm/include/llvm/Analysis/SparsePropagation.h (+3-3) 


``````````diff
diff --git a/llvm/include/llvm/Analysis/SparsePropagation.h b/llvm/include/llvm/Analysis/SparsePropagation.h
index cc79870229873..b85e11942a320 100644
--- a/llvm/include/llvm/Analysis/SparsePropagation.h
+++ b/llvm/include/llvm/Analysis/SparsePropagation.h
@@ -244,13 +244,13 @@ SparseSolver<LatticeKey, LatticeVal, KeyInfo>::getValueState(LatticeKey Key) {
 template <class LatticeKey, class LatticeVal, class KeyInfo>
 void SparseSolver<LatticeKey, LatticeVal, KeyInfo>::UpdateState(LatticeKey Key,
                                                                 LatticeVal LV) {
-  auto I = ValueState.find(Key);
-  if (I != ValueState.end() && I->second == LV)
+  auto [I, Inserted] = ValueState.try_emplace(Key);
+  if (!Inserted && I->second == LV)
     return; // No change.
 
   // Update the state of the given LatticeKey and add its corresponding LLVM
   // value to the work list.
-  ValueState[Key] = std::move(LV);
+  I->second = std::move(LV);
   if (Value *V = KeyInfo::getValueFromLatticeKey(Key))
     ValueWorkList.push_back(V);
 }

``````````

</details>


https://github.com/llvm/llvm-project/pull/126851