[clang] b48b422 - [Serialization] Avoid repeated hash lookups (NFC) (#126429)

[via cfe-commits]

Author: Kazu Hirata
Date: 2025-02-09T13:33:46-08:00
New Revision: b48b422c08e85e6afd39aea7341fdf08d07d3e08

URL: https://github.com/llvm/llvm-project/commit/b48b422c08e85e6afd39aea7341fdf08d07d3e08
DIFF: https://github.com/llvm/llvm-project/commit/b48b422c08e85e6afd39aea7341fdf08d07d3e08.diff

LOG: [Serialization] Avoid repeated hash lookups (NFC) (#126429)

Added: 
    

Modified: 
    clang/lib/Serialization/ASTReader.cpp

Removed: 
    


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diff  --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index b74bd586e74d7a9..3c64b67503195c3 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -645,10 +645,11 @@ collectMacroDefinitions(const PreprocessorOptions &PPOpts,
 
     // For an #undef'd macro, we only care about the name.
     if (IsUndef) {
-      if (MacroNames && !Macros.count(MacroName))
+      auto [It, Inserted] = Macros.try_emplace(MacroName);
+      if (MacroNames && Inserted)
         MacroNames->push_back(MacroName);
 
-      Macros[MacroName] = std::make_pair("", true);
+      It->second = std::make_pair("", true);
       continue;
     }
 
@@ -661,9 +662,10 @@ collectMacroDefinitions(const PreprocessorOptions &PPOpts,
       MacroBody = MacroBody.substr(0, End);
     }
 
-    if (MacroNames && !Macros.count(MacroName))
+    auto [It, Inserted] = Macros.try_emplace(MacroName);
+    if (MacroNames && Inserted)
       MacroNames->push_back(MacroName);
-    Macros[MacroName] = std::make_pair(MacroBody, false);
+    It->second = std::make_pair(MacroBody, false);
   }
 }