Lazily load the controlling macros for all of the headers known in the

PCH file. In the Cocoa-prefixed "Hello, World" benchmark, this takes
us from reading 503 identifiers down to 37 and from 470 macros down to
4. It also results in an 8% performance improvement.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70094 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 1 deletions

diff --git a/include/clang/Basic/IdentifierTable.h b/include/clang/Basic/IdentifierTable.h
index 235c19081c..083196a2c1 100644
--- a/include/clang/Basic/IdentifierTable.h
+++ b/include/clang/Basic/IdentifierTable.h
@@ -234,7 +234,20 @@ public:
   ///  be found.
   virtual IdentifierInfo* get(const char *NameStart, const char *NameEnd) = 0;
 };  
-  
+
+/// \brief An abstract class used to resolve numerical identifier
+/// references (meaningful only to some external source) into
+/// IdentifierInfo pointers.
+class ExternalIdentifierLookup {
+public:
+  virtual ~ExternalIdentifierLookup();
+
+  /// \brief Return the identifier associated with the given ID number.
+  ///
+  /// The ID 0 is associated with the NULL identifier.
+  virtual IdentifierInfo *GetIdentifier(unsigned ID) = 0;
+};
+
 /// IdentifierTable - This table implements an efficient mapping from strings to
 /// IdentifierInfo nodes.  It has no other purpose, but this is an
 /// extremely performance-critical piece of the code, as each occurrance of