[clang] [AST] Avoid repeated map lookups (NFC) (PR #122858)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/122858.diff


1 Files Affected:

- (modified) clang/lib/AST/ExternalASTMerger.cpp (+2-2) 


``````````diff
diff --git a/clang/lib/AST/ExternalASTMerger.cpp b/clang/lib/AST/ExternalASTMerger.cpp
index 8bad3b36244e15..7f7816e1b10eae 100644
--- a/clang/lib/AST/ExternalASTMerger.cpp
+++ b/clang/lib/AST/ExternalASTMerger.cpp
@@ -276,8 +276,8 @@ bool ExternalASTMerger::HasImporterForOrigin(ASTContext &OriginContext) {
 template <typename CallbackType>
 void ExternalASTMerger::ForEachMatchingDC(const DeclContext *DC,
                                           CallbackType Callback) {
-  if (Origins.count(DC)) {
-    ExternalASTMerger::DCOrigin Origin = Origins[DC];
+  if (auto It = Origins.find(DC); It != Origins.end()) {
+    ExternalASTMerger::DCOrigin Origin = It->second;
     LazyASTImporter &Importer = LazyImporterForOrigin(*this, *Origin.AST);
     Callback(Importer, Importer.GetReverse(), Origin.DC);
   } else {

``````````

</details>


https://github.com/llvm/llvm-project/pull/122858