Mips specific inline assembler constraint 'R'

'R' An address that can be sued in a non-macro load or store.
This patch includes a positive test case.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176452 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/Mips/MipsISelLowering.cpp

@@ -3880,6 +3880,8 @@ getConstraintType(const std::string &Constraint) const
       case 'l':
       case 'x':
         return C_RegisterClass;
+      case 'R':
+        return C_Memory;
     }
   }
   return TargetLowering::getConstraintType(Constraint);
@@ -3928,6 +3930,9 @@ MipsTargetLowering::getSingleConstraintMatchWeight(
     if (isa<ConstantInt>(CallOperandVal))
       weight = CW_Constant;
     break;
+  case 'R':
+    weight = CW_Memory;
+    break;
   }
   return weight;
 }