[MIR] Adding support for Named Virtual Registers in MIR.

llvm-svn: 328887
diff --git a/llvm/lib/CodeGen/MIRPrinter.cpp b/llvm/lib/CodeGen/MIRPrinter.cpp
index 25cf937..8452b4e 100644
--- a/llvm/lib/CodeGen/MIRPrinter.cpp
+++ b/llvm/lib/CodeGen/MIRPrinter.cpp
@@ -267,6 +267,8 @@
     unsigned Reg = TargetRegisterInfo::index2VirtReg(I);
     yaml::VirtualRegisterDefinition VReg;
     VReg.ID = I;
+    if (RegInfo.getVRegName(Reg) != "")
+      continue;
     ::printRegClassOrBank(Reg, VReg.Class, RegInfo, TRI);
     unsigned PreferredReg = RegInfo.getSimpleHint(Reg);
     if (PreferredReg)