Optimize unqualified/global name lookup in modules by introducing a

generational scheme for identifiers that avoids searching the hash
tables of a given module more than once for a given
identifier. Previously, loading any new module invalidated all of the
previous lookup results for all identifiers, causing us to perform the
lookups repeatedly.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148412 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 1 deletions

diff --git a/include/clang/Serialization/Module.h b/include/clang/Serialization/Module.h
index ad2c98e695..831a873ac1 100644
--- a/include/clang/Serialization/Module.h
+++ b/include/clang/Serialization/Module.h
@@ -57,7 +57,7 @@ struct DeclContextInfo {
 /// other modules.
 class ModuleFile {
 public:
-  ModuleFile(ModuleKind Kind);
+  ModuleFile(ModuleKind Kind, unsigned Generation);
   ~ModuleFile();
 
   // === General information ===
@@ -72,6 +72,9 @@ public:
   /// user.
   bool DirectlyImported;
 
+  /// \brief The generation of which this module file is a part.
+  unsigned Generation;
+  
   /// \brief The memory buffer that stores the data associated with
   /// this AST file.
   llvm::OwningPtr<llvm::MemoryBuffer> Buffer;