Honour subreg machine operands during asmprinting

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86303 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp b/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp
index 6a0c898..a3f52cd 100644
--- a/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp
+++ b/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp
@@ -347,6 +347,9 @@
                                                &ARM::DPR_VFP2RegClass);
       O << getRegisterName(DReg) << '[' << (RegNum & 1) << ']';
     } else {
+      if (unsigned SubReg = MO.getSubReg())
+        Reg = TRI->getSubReg(Reg, SubReg);
+
       O << getRegisterName(Reg);
     }
     break;