MC asm parser macro argument count was wrong when empty.

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

rdar://11057257

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152967 91177308-0d34-0410-b5e6-96231b3b80d8

lib/MC/MCParser/AsmParser.cpp

@@ -1528,6 +1528,11 @@ bool AsmParser::HandleMacroEntry(StringRef Name, SMLoc NameLoc,
     }
     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.

test/MC/AsmParser/macro-args.s

@@ -8,3 +8,13 @@
 GET    is_sse, %eax
 
 // CHECK: movl	is_sse@GOTOFF(%ebx), %eax
+
+.macro bar
+    .long $n
+.endm
+
+bar 1, 2, 3
+bar
+
+// CHECK: .long 3
+// CHECK: .long 0