[clang] 6eda66b - PR50294: Fix a performance regression from 2c9dbcd.

[Richard Smith via cfe-commits]

Author: Richard Smith
Date: 2021-09-01T18:00:07-07:00
New Revision: 6eda66b0a9f793c65852aa94430ae9bd891bcf63

URL: https://github.com/llvm/llvm-project/commit/6eda66b0a9f793c65852aa94430ae9bd891bcf63
DIFF: https://github.com/llvm/llvm-project/commit/6eda66b0a9f793c65852aa94430ae9bd891bcf63.diff

LOG: PR50294: Fix a performance regression from 2c9dbcd.

Per the contract of ReadLateParsedTemplates, we should not be returning
the same results multiple times. No functionality change intended, other
than to runtime.

Thanks to Luboš Luňák for identifying the cause of the regression!

Added: 
    

Modified: 
    clang/lib/Serialization/ASTReader.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 128350ce9ff8f..dfa7d55af735d 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -8412,6 +8412,8 @@ void ASTReader::ReadLateParsedTemplates(
       LPTMap.insert(std::make_pair(FD, std::move(LT)));
     }
   }
+
+  LateParsedTemplates.clear();
 }
 
 void ASTReader::LoadSelector(Selector Sel) {