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

4 files changed, 14 insertions, 4 deletions

diff --git a/lib/Lex/Lexer.cpp b/lib/Lex/Lexer.cpp
index 19b3121c64..f7937d5d70 100644
--- a/lib/Lex/Lexer.cpp
+++ b/lib/Lex/Lexer.cpp
@@ -560,7 +560,9 @@ FinishIdentifier:
     
     // Finally, now that we know we have an identifier, pass this off to the
     // preprocessor, which may macro expand it or something.
-    return PP->HandleIdentifier(Result);
+    if (Result.getIdentifierInfo()->isHandleIdentifierCase())
+      PP->HandleIdentifier(Result);
+    return;
   }
   
   // Otherwise, $,\,? in identifier found.  Enter slower path.
diff --git a/lib/Lex/PTHLexer.cpp b/lib/Lex/PTHLexer.cpp
index 81349171fe..99bb3f795d 100644
--- a/lib/Lex/PTHLexer.cpp
+++ b/lib/Lex/PTHLexer.cpp
@@ -143,7 +143,9 @@ LexNextToken:
 
   if (TKind == tok::identifier) {
     MIOpt.ReadToken();
-    return PP->HandleIdentifier(Tok);
+    if (Tok.getIdentifierInfo()->isHandleIdentifierCase())
+      PP->HandleIdentifier(Tok);
+    return;
   }
   
   if (TKind == tok::eof) {
diff --git a/lib/Lex/Preprocessor.cpp b/lib/Lex/Preprocessor.cpp
index 5d9fc9567d..e53c392c38 100644
--- a/lib/Lex/Preprocessor.cpp
+++ b/lib/Lex/Preprocessor.cpp
@@ -718,6 +718,11 @@ IdentifierInfo *Preprocessor::LookUpIdentifierInfo(Token &Identifier,
 /// HandleIdentifier - This callback is invoked when the lexer reads an
 /// identifier.  This callback looks up the identifier in the map and/or
 /// potentially macro expands it or turns it into a named token (like 'for').
+///
+/// Note that callers of this method are guarded by checking the
+/// IdentifierInfo's 'isHandleIdentifierCase' bit.  If this method changes, the
+/// IdentifierInfo methods that compute these properties will need to change to
+/// match.
 void Preprocessor::HandleIdentifier(Token &Identifier) {
   assert(Identifier.getIdentifierInfo() &&
          "Can't handle identifiers without identifier info!");
diff --git a/lib/Lex/TokenLexer.cpp b/lib/Lex/TokenLexer.cpp
index 82c4d926ae..c945843459 100644
--- a/lib/Lex/TokenLexer.cpp
+++ b/lib/Lex/TokenLexer.cpp
@@ -326,8 +326,9 @@ void TokenLexer::Lex(Token &Tok) {
   }
   
   // 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.
 }