Add a bit to IdentifierInfo that acts as a simple predicate which
tells us whether Preprocessor::HandleIdentifier needs to be called.
Because this method is only rarely needed, this saves a call and a
bunch of random checks.  This drops the time in HandleIdentifier 
from 3.52ms to .98ms on cocoa.h on my machine.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62675 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/TokenLexer.cpp b/lib/Lex/TokenLexer.cpp
index 82c4d92..c945843 100644
--- a/lib/Lex/TokenLexer.cpp
+++ b/lib/Lex/TokenLexer.cpp
@@ -326,8 +326,9 @@
   }
   
   // Handle recursive expansion!
-  if (Tok.getIdentifierInfo() && !DisableMacroExpansion)
-    return PP.HandleIdentifier(Tok);
+  if (Tok.getIdentifierInfo() && !DisableMacroExpansion &&
+      Tok.getIdentifierInfo()->isHandleIdentifierCase())
+    PP.HandleIdentifier(Tok);
 
   // Otherwise, return a normal token.
 }