Simplify identifier lookup in raw mode, implementing Preprocessor/macro_fn_lparen_scan2.c.

llvm-svn: 38744

clang/Lex/Lexer.cpp

@@ -359,6 +359,10 @@ FinishIdentifier:
     FormTokenWithChars(Result, CurPtr);
     Result.SetKind(tok::identifier);
     
+    // If we are in raw mode, return this identifier raw.  There is no need to
+    // look up identifier information or attempt to macro expand it.
+    if (LexingRawMode) return;
+    
     // Fill in Result.IdentifierInfo, looking up the identifier in the
     // identifier table.
     PP.LookUpIdentifierInfo(Result, IdStart);

clang/Lex/MacroExpander.cpp

@@ -508,6 +508,15 @@ void MacroExpander::PasteTokens(LexerToken &Tok) {
     ++CurToken;
     Tok = Result;
   } while (!isAtEnd() && (*MacroTokens)[CurToken].getKind() == tok::hashhash);
+  
+  // Now that we got the result token, it will be subject to expansion.  Since
+  // token pasting re-lexes the result token in raw mode, identifier information
+  // isn't looked up.  As such, if the result is an identifier, look up id info.
+  if (Tok.getKind() == tok::identifier) {
+    // Look up the identifier info for the token.  We disabled identifier lookup
+    // by saying we're skipping contents, so we need to do this manually.
+    Tok.SetIdentifierInfo(PP.LookUpIdentifierInfo(Tok));
+  }
 }
 
 /// isNextTokenLParen - If the next token lexed will pop this macro off the

clang/Lex/Preprocessor.cpp

@@ -971,12 +971,9 @@ IdentifierInfo *Preprocessor::LookUpIdentifierInfo(LexerToken &Identifier,
 /// 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').
 void Preprocessor::HandleIdentifier(LexerToken &Identifier) {
-  if (Identifier.getIdentifierInfo() == 0) {
-    // If we are skipping tokens (because we are in a #if 0 block), there will
-    // be no identifier info, just return the token.
-    assert(isSkipping() && "Token isn't an identifier?");
-    return;
-  }
+  assert(Identifier.getIdentifierInfo() &&
+         "Can't handle identifiers without identifier info!");
+  
   IdentifierInfo &II = *Identifier.getIdentifierInfo();
 
   // If this identifier was poisoned, and if it was not produced from a macro

clang/test/Preprocessor/macro_fn_lparen_scan2.c

@@ -0,0 +1,7 @@
+// RUN: clang -E %s | grep 'FUNC (3+1);'
+
+#define F(a) a 
+#define FUNC(a) (a+1) 
+
+F(FUNC) FUNC (3); /* final token sequence is FUNC(3+1) */ 
+