[ARC] Add ARCOptAddrMode pass to generate postincrement loads/stores.

Build on newly introduced ARC postincrement loads/stores from r356200.

Patch By Denis Antrushin! <denis@synopsys.com>

Differential Revision: https://reviews.llvm.org/D59409

llvm-svn: 356606

Author: petecoup

llvm/lib/Target/ARC/ARC.h

@@ -25,6 +25,7 @@ class ARCTargetMachine;
 FunctionPass *createARCISelDag(ARCTargetMachine &TM,
                                CodeGenOpt::Level OptLevel);
 FunctionPass *createARCExpandPseudosPass();
+FunctionPass *createARCOptAddrMode();
 FunctionPass *createARCBranchFinalizePass();
 
 } // end namespace llvm

llvm/lib/Target/ARC/ARCFrameLowering.cpp

@@ -311,8 +311,8 @@ void ARCFrameLowering::emitEpilogue(MachineFunction &MF,
   // Now, pop fp if necessary.
   if (hasFP(MF)) {
     BuildMI(MBB, MBBI, MBB.findDebugLoc(MBBI), TII->get(ARC::LD_AB_rs9))
-        .addReg(ARC::SP, RegState::Define)
         .addReg(ARC::FP, RegState::Define)
+        .addReg(ARC::SP, RegState::Define)
         .addReg(ARC::SP)
         .addImm(4);
   }