Fix a VFP binary arithmetic instruction encoding bug.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59116 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMCodeEmitter.cpp b/lib/Target/ARM/ARMCodeEmitter.cpp
index e877aa7..2fdd9ce 100644
--- a/lib/Target/ARM/ARMCodeEmitter.cpp
+++ b/lib/Target/ARM/ARMCodeEmitter.cpp
@@ -1102,7 +1102,7 @@
 
   // Encode Dn / Sn.
   if ((TID.TSFlags & ARMII::FormMask) == ARMII::VFPBinaryFrm)
-    Binary |= encodeVFPRn(MI, OpIdx);
+    Binary |= encodeVFPRn(MI, OpIdx++);
 
   if (OpIdx == TID.getNumOperands() ||
       TID.OpInfo[OpIdx].isPredicate() ||