[MIR] Add support for addrspace in MIR

Add support for printing / parsing the addrspace of a MachineMemOperand.

Fixes PR35970.

Differential Revision: https://reviews.llvm.org/D42502

llvm-svn: 323521
diff --git a/llvm/lib/CodeGen/MIRPrinter.cpp b/llvm/lib/CodeGen/MIRPrinter.cpp
index 0931617..658b596 100644
--- a/llvm/lib/CodeGen/MIRPrinter.cpp
+++ b/llvm/lib/CodeGen/MIRPrinter.cpp
@@ -892,6 +892,8 @@
     OS << ", !range ";
     Op.getRanges()->printAsOperand(OS, MST);
   }
+  if (unsigned AS = Op.getAddrSpace())
+    OS << ", addrspace " << AS;
   OS << ')';
 }