Prep for merging 3.4: Undo changes from 3.3 branch

lib/Target/R600/AMDGPUTargetMachine.cpp

 //===-- AMDGPUTargetMachine.cpp - TargetMachine for hw codegen targets-----===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 /// \file
@@ skipping 97 matching lines @@
 AMDGPUPassConfig::addPreISel() {
   const AMDGPUSubtarget &ST = TM->getSubtarget<AMDGPUSubtarget>();
   if (ST.device()->getGeneration() > AMDGPUDeviceInfo::HD6XXX) {
     addPass(createAMDGPUStructurizeCFGPass());
     addPass(createSIAnnotateControlFlowPass());
   }
   return false;
 }
 
 bool AMDGPUPassConfig::addInstSelector() {
+  addPass(createAMDGPUPeepholeOpt(*TM));
   addPass(createAMDGPUISelDag(getAMDGPUTargetMachine()));
 
   const AMDGPUSubtarget &ST = TM->getSubtarget<AMDGPUSubtarget>();
   if (ST.device()->getGeneration() <= AMDGPUDeviceInfo::HD6XXX) {
     // This callbacks this pass uses are not implemented yet on SI.
     addPass(createAMDGPUIndirectAddressingPass(*TM));
   }
   return false;
 }
 
@@ skipping 27 matching lines @@
     addPass(&FinalizeMachineBundlesID);
     addPass(createR600Packetizer(*TM));
     addPass(createR600ControlFlowFinalizer(*TM));
   } else {
     addPass(createSILowerControlFlowPass(*TM));
   }
 
   return false;
 }