[clang] [APINotes] Avoid repeated hash lookups (NFC) (PR #107758)

[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/107758.diff


1 Files Affected:

- (modified) clang/lib/APINotes/APINotesWriter.cpp (+2-8) 


``````````diff
diff --git a/clang/lib/APINotes/APINotesWriter.cpp b/clang/lib/APINotes/APINotesWriter.cpp
index c452677983bb36..2f4e5e803f6a2b 100644
--- a/clang/lib/APINotes/APINotesWriter.cpp
+++ b/clang/lib/APINotes/APINotesWriter.cpp
@@ -147,14 +147,8 @@ class APINotesWriter::Implementation {
     for (auto piece : SelectorRef.Identifiers)
       Selector.Identifiers.push_back(getIdentifier(piece));
 
-    // Look for the stored selector.
-    auto Known = SelectorIDs.find(Selector);
-    if (Known != SelectorIDs.end())
-      return Known->second;
-
-    // Add to the selector table.
-    Known = SelectorIDs.insert({Selector, SelectorIDs.size()}).first;
-    return Known->second;
+    // Look for the stored selector.  Add to the selector table if missing.
+    return SelectorIDs.try_emplace(Selector, SelectorIDs.size()).first->second;
   }
 
 private:

``````````

</details>


https://github.com/llvm/llvm-project/pull/107758