[cfe-commits] r38747 - in /cfe/cfe/trunk: Lex/MacroExpander.cpp Lex/Preprocessor.cpp include/clang/Lex/Preprocessor.h

[sabre at cs.uiuc.edu]

Author: sabre
Date: Wed Jul 11 11:24:17 2007
New Revision: 38747

URL: http://llvm.org/viewvc/llvm-project?rev=38747&view=rev
Log:
Add optimization for identifier##identifier -> identifier, the most common case of token pasting.

Modified:
    cfe/cfe/trunk/Lex/MacroExpander.cpp
    cfe/cfe/trunk/Lex/Preprocessor.cpp
    cfe/cfe/trunk/include/clang/Lex/Preprocessor.h

Modified: cfe/cfe/trunk/Lex/MacroExpander.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/cfe/trunk/Lex/MacroExpander.cpp?rev=38747&r1=38746&r2=38747&view=diff

==============================================================================
--- cfe/cfe/trunk/Lex/MacroExpander.cpp (original)
+++ cfe/cfe/trunk/Lex/MacroExpander.cpp Wed Jul 11 11:24:17 2007
@@ -455,9 +455,18 @@
     // and emit an error that it is unterminated.
     if (Tok.getKind() == tok::slash && RHS.getKind() == tok::star) {
       isInvalid = true;
+    } else if (Tok.getKind() == tok::identifier && 
+               Tok.getKind() == tok::identifier) {
+      // Common paste case: identifier+identifier = identifier.  Avoid creating
+      // a lexer and other overhead.
+      PP.IncrementPasteCounter(true);
+      Result.StartToken();
+      Result.SetKind(tok::identifier);
+      Result.SetLocation(ResultTokLoc);
+      Result.SetLength(LHSLen+RHSLen);
     } else {
-      // FIXME: Handle common cases: ident+ident, ident+simplenumber here.
-
+      PP.IncrementPasteCounter(false);
+      
       // Make a lexer to lex this string from.
       SourceManager &SourceMgr = PP.getSourceManager();
       const char *ResultStrData = SourceMgr.getCharacterData(ResultTokLoc);

Modified: cfe/cfe/trunk/Lex/Preprocessor.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/cfe/trunk/Lex/Preprocessor.cpp?rev=38747&r1=38746&r2=38747&view=diff

==============================================================================
--- cfe/cfe/trunk/Lex/Preprocessor.cpp (original)
+++ cfe/cfe/trunk/Lex/Preprocessor.cpp Wed Jul 11 11:24:17 2007
@@ -51,7 +51,7 @@
   NumIf = NumElse = NumEndif = 0;
   NumEnteredSourceFiles = 0;
   NumMacroExpanded = NumFnMacroExpanded = NumBuiltinMacroExpanded = 0;
-  NumFastMacroExpanded = 0;
+  NumFastMacroExpanded = NumTokenPaste = NumFastTokenPaste = 0;
   MaxIncludeStackDepth = 0; NumMultiIncludeFileOptzn = 0;
   NumSkipped = 0;
     
@@ -193,6 +193,9 @@
   std::cerr << NumMacroExpanded << "/" << NumFnMacroExpanded << "/"
             << NumBuiltinMacroExpanded << " obj/fn/builtin macros expanded, "
             << NumFastMacroExpanded << " on the fast path.\n";
+  std::cerr << (NumFastTokenPaste+NumTokenPaste)
+            << " token paste (##) operations performed, "
+            << NumFastTokenPaste << " on the fast path.\n";
 }
 
 //===----------------------------------------------------------------------===//

Modified: cfe/cfe/trunk/include/clang/Lex/Preprocessor.h
URL: http://llvm.org/viewvc/llvm-project/cfe/cfe/trunk/include/clang/Lex/Preprocessor.h?rev=38747&r1=38746&r2=38747&view=diff

==============================================================================
--- cfe/cfe/trunk/include/clang/Lex/Preprocessor.h (original)
+++ cfe/cfe/trunk/include/clang/Lex/Preprocessor.h Wed Jul 11 11:24:17 2007
@@ -200,7 +200,7 @@
   unsigned NumIf, NumElse, NumEndif;
   unsigned NumEnteredSourceFiles, MaxIncludeStackDepth,NumMultiIncludeFileOptzn;
   unsigned NumMacroExpanded, NumFnMacroExpanded, NumBuiltinMacroExpanded;
-  unsigned NumFastMacroExpanded;
+  unsigned NumFastMacroExpanded, NumTokenPaste, NumFastTokenPaste;
   unsigned NumSkipped;
 public:
   Preprocessor(Diagnostic &diags, const LangOptions &opts, FileManager &FM,
@@ -392,6 +392,17 @@
   void DumpToken(const LexerToken &Tok, bool DumpFlags = false) const;
   void DumpMacro(const MacroInfo &MI) const;
   
+  /// IncrementPasteCounter - Increment the counters for the number of token
+  /// paste operations performed.  If fast was specified, this is a 'fast paste'
+  /// case we handled.
+  /// 
+  void IncrementPasteCounter(bool isFast) {
+    if (isFast)
+      ++NumFastTokenPaste;
+    else
+      ++NumTokenPaste;
+  }
+  
   void PrintStats();
 
   //===--------------------------------------------------------------------===//