Add missing explicit writeback operand to tSTMIA_UPD.

rdar://10014745

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138457 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index b76ba3e..32a4fbb 100644
--- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -3152,7 +3152,7 @@
   }
   case ARM::tSTMIA_UPD: {
     bool listContainsBase;
-    if (checkLowRegisterList(Inst, 3, 0, 0, listContainsBase))
+    if (checkLowRegisterList(Inst, 4, 0, 0, listContainsBase))
       return Error(Operands[4]->getStartLoc(),
                    "registers must be in range r0-r7");
     break;