[Hexagon] Converting from ADD_rr to A2_add which has encoding bits.
Adding test to show correct instruction selection and encoding.

llvm-svn: 222249
diff --git a/llvm/lib/Target/Hexagon/HexagonExpandPredSpillCode.cpp b/llvm/lib/Target/Hexagon/HexagonExpandPredSpillCode.cpp
index 34319ee..8ef4c3a 100644
--- a/llvm/lib/Target/Hexagon/HexagonExpandPredSpillCode.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonExpandPredSpillCode.cpp
@@ -100,7 +100,7 @@
             BuildMI(*MBB, MII, MI->getDebugLoc(),
                     TII->get(Hexagon::CONST32_Int_Real),
                       HEXAGON_RESERVED_REG_1).addImm(Offset);
-            BuildMI(*MBB, MII, MI->getDebugLoc(), TII->get(Hexagon::ADD_rr),
+            BuildMI(*MBB, MII, MI->getDebugLoc(), TII->get(Hexagon::A2_add),
                     HEXAGON_RESERVED_REG_1)
               .addReg(FP).addReg(HEXAGON_RESERVED_REG_1);
             BuildMI(*MBB, MII, MI->getDebugLoc(), TII->get(Hexagon::TFR_RsPd),
@@ -146,7 +146,7 @@
             BuildMI(*MBB, MII, MI->getDebugLoc(),
                     TII->get(Hexagon::CONST32_Int_Real),
                       HEXAGON_RESERVED_REG_1).addImm(Offset);
-            BuildMI(*MBB, MII, MI->getDebugLoc(), TII->get(Hexagon::ADD_rr),
+            BuildMI(*MBB, MII, MI->getDebugLoc(), TII->get(Hexagon::A2_add),
                     HEXAGON_RESERVED_REG_1)
               .addReg(FP)
               .addReg(HEXAGON_RESERVED_REG_1);