MC machine encoding for simple aritmetic instructions that use a shifted
register operand.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116259 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMAddressingModes.h b/lib/Target/ARM/ARMAddressingModes.h
index db48100..7f68c81 100644
--- a/lib/Target/ARM/ARMAddressingModes.h
+++ b/lib/Target/ARM/ARMAddressingModes.h
@@ -50,6 +50,16 @@
     }
   }
 
+  static inline unsigned getShiftOpcEncoding(ShiftOpc Op) {
+    switch (Op) {
+    default: assert(0 && "Unknown shift opc!");
+    case ARM_AM::asr: return 2;
+    case ARM_AM::lsl: return 0;
+    case ARM_AM::lsr: return 1;
+    case ARM_AM::ror: return 3;
+    }
+  }
+
   static inline ShiftOpc getShiftOpcForNode(SDValue N) {
     switch (N.getOpcode()) {
     default:          return ARM_AM::no_shift;