Introduce a simple "hint" scheme to eliminate the quadratic behavior

associated with deserializing macro history for an identifier.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@165729 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 4 insertions, 3 deletions

diff --git a/include/clang/Lex/Preprocessor.h b/include/clang/Lex/Preprocessor.h
index 2c0814c910..7888a26fcb 100644
--- a/include/clang/Lex/Preprocessor.h
+++ b/include/clang/Lex/Preprocessor.h
@@ -519,7 +519,8 @@ public:
   /// \brief Specify a macro for this identifier.
   void setMacroInfo(IdentifierInfo *II, MacroInfo *MI);
   /// \brief Add a MacroInfo that was loaded from an AST file.
-  void addLoadedMacroInfo(IdentifierInfo *II, MacroInfo *MI);
+  void addLoadedMacroInfo(IdentifierInfo *II, MacroInfo *MI,
+                          MacroInfo *Hint = 0);
   /// \brief Make the given MacroInfo, that was loaded from an AST file and
   /// previously hidden, visible.
   void makeLoadedMacroInfoVisible(IdentifierInfo *II, MacroInfo *MI);
diff --git a/include/clang/Serialization/ASTReader.h b/include/clang/Serialization/ASTReader.h
index 2a9afc92e9..4e8531a820 100644
--- a/include/clang/Serialization/ASTReader.h
+++ b/include/clang/Serialization/ASTReader.h
@@ -1433,7 +1433,7 @@ public:
                                                     unsigned LocalID);
 
   /// \brief Retrieve the macro with the given ID.
-  MacroInfo *getMacro(serialization::MacroID ID);
+  MacroInfo *getMacro(serialization::MacroID ID, MacroInfo *Hint = 0);
 
   /// \brief Retrieve the global macro ID corresponding to the given local
   /// ID within the given module file.
@@ -1582,7 +1582,7 @@ public:
   Expr *ReadSubExpr();
 
   /// \brief Reads the macro record located at the given offset.
-  void ReadMacroRecord(ModuleFile &F, uint64_t Offset);
+  void ReadMacroRecord(ModuleFile &F, uint64_t Offset, MacroInfo *Hint = 0);
 
   /// \brief Determine the global preprocessed entity ID that corresponds to
   /// the given local ID within the given module.