MC asm parser macro argument count was wrong when empty.

 evaluated to '1' when the argument list was empty (should be '0').

rdar://11057257

llvm-svn: 152967
diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index bd5956f..41ad164 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -1528,6 +1528,11 @@
     }
     Lex();
   }
+  // If there weren't any arguments, erase the token vector so everything
+  // else knows that. Leaving around the vestigal empty token list confuses
+  // things.
+  if (MacroArguments.size() == 1 && MacroArguments.back().empty())
+    MacroArguments.clear();
 
   // Macro instantiation is lexical, unfortunately. We construct a new buffer
   // to hold the macro body with substitutions.