ModuloScheduling moved to lib/Target/SparcV9 as it is SparcV9-specific

llvm-svn: 16902

1 files changed, 1967 insertions, 0 deletions

diff --git a/llvm/lib/Target/SparcV9/ModuloScheduling/ModuloScheduling.cpp b/llvm/lib/Target/SparcV9/ModuloScheduling/ModuloScheduling.cpp
new file mode 100644
index 00000000000..ffb3404ff8e
--- /dev/null
+++ b/llvm/lib/Target/SparcV9/ModuloScheduling/ModuloScheduling.cpp
@@ -0,0 +1,1967 @@
+//===-- ModuloScheduling.cpp - ModuloScheduling  ----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// 
+//  This ModuloScheduling pass is based on the Swing Modulo Scheduling 
+//  algorithm. 
+// 
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "ModuloSched"
+
+#include "ModuloScheduling.h"
+#include "llvm/Instructions.h"
+#include "llvm/Function.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/Support/CFG.h"
+#include "llvm/Target/TargetSchedInfo.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/GraphWriter.h"
+#include "llvm/ADT/StringExtras.h"
+#include <cmath>
+#include <algorithm>
+#include <fstream>
+#include <sstream>
+#include <utility>
+#include <vector>
+#include "../../Target/SparcV9/MachineCodeForInstruction.h"
+#include "../../Target/SparcV9/SparcV9TmpInstr.h"
+#include "../../Target/SparcV9/SparcV9Internals.h"
+#include "../../Target/SparcV9/SparcV9RegisterInfo.h"
+using namespace llvm;
+
+/// Create ModuloSchedulingPass
+///
+FunctionPass *llvm::createModuloSchedulingPass(TargetMachine & targ) {
+  DEBUG(std::cerr << "Created ModuloSchedulingPass\n");
+  return new ModuloSchedulingPass(targ); 
+}
+
+
+//Graph Traits for printing out the dependence graph
+template<typename GraphType>
+static void WriteGraphToFile(std::ostream &O, const std::string &GraphName,
+                             const GraphType &GT) {
+  std::string Filename = GraphName + ".dot";
+  O << "Writing '" << Filename << "'...";
+  std::ofstream F(Filename.c_str());
+  
+  if (F.good())
+    WriteGraph(F, GT);
+  else
+    O << "  error opening file for writing!";
+  O << "\n";
+};
+
+//Graph Traits for printing out the dependence graph
+namespace llvm {
+
+  template<>
+  struct DOTGraphTraits<MSchedGraph*> : public DefaultDOTGraphTraits {
+    static std::string getGraphName(MSchedGraph *F) {
+      return "Dependence Graph";
+    }
+    
+    static std::string getNodeLabel(MSchedGraphNode *Node, MSchedGraph *Graph) {
+      if (Node->getInst()) {
+	std::stringstream ss;
+	ss << *(Node->getInst());
+	return ss.str(); //((MachineInstr*)Node->getInst());
+      }
+      else
+	return "No Inst";
+    }
+    static std::string getEdgeSourceLabel(MSchedGraphNode *Node,
+					  MSchedGraphNode::succ_iterator I) {
+      //Label each edge with the type of dependence
+      std::string edgelabel = "";
+      switch (I.getEdge().getDepOrderType()) {
+	
+      case MSchedGraphEdge::TrueDep: 
+	edgelabel = "True";
+	break;
+    
+      case MSchedGraphEdge::AntiDep: 
+	edgelabel =  "Anti";
+	break;
+	
+      case MSchedGraphEdge::OutputDep: 
+	edgelabel = "Output";
+	break;
+	
+      default:
+	edgelabel = "Unknown";
+	break;
+      }
+
+      //FIXME
+      int iteDiff = I.getEdge().getIteDiff();
+      std::string intStr = "(IteDiff: ";
+      intStr += itostr(iteDiff);
+
+      intStr += ")";
+      edgelabel += intStr;
+
+      return edgelabel;
+    }
+  };
+}
+
+/// ModuloScheduling::runOnFunction - main transformation entry point
+/// The Swing Modulo Schedule algorithm has three basic steps:
+/// 1) Computation and Analysis of the dependence graph
+/// 2) Ordering of the nodes
+/// 3) Scheduling
+/// 
+bool ModuloSchedulingPass::runOnFunction(Function &F) {
+  
+  bool Changed = false;
+  
+  DEBUG(std::cerr << "Creating ModuloSchedGraph for each valid BasicBlock in " + F.getName() + "\n");
+  
+  //Get MachineFunction
+  MachineFunction &MF = MachineFunction::get(&F);
+  
+  //Worklist
+  std::vector<MachineBasicBlock*> Worklist;
+  
+  //Iterate over BasicBlocks and put them into our worklist if they are valid
+  for (MachineFunction::iterator BI = MF.begin(); BI != MF.end(); ++BI)
+    if(MachineBBisValid(BI)) 
+      Worklist.push_back(&*BI);
+  
+  DEBUG(if(Worklist.size() == 0) std::cerr << "No single basic block loops in function to ModuloSchedule\n");
+
+  //Iterate over the worklist and perform scheduling
+  for(std::vector<MachineBasicBlock*>::iterator BI = Worklist.begin(),  
+	BE = Worklist.end(); BI != BE; ++BI) {
+    
+    MSchedGraph *MSG = new MSchedGraph(*BI, target);
+    
+    //Write Graph out to file
+    DEBUG(WriteGraphToFile(std::cerr, F.getName(), MSG));
+    
+    //Print out BB for debugging
+    DEBUG(std::cerr << "ModuloScheduling BB: \n"; (*BI)->print(std::cerr));
+    
+    //Calculate Resource II
+    int ResMII = calculateResMII(*BI);
+    
+    //Calculate Recurrence II
+    int RecMII = calculateRecMII(MSG, ResMII);
+    
+    //Our starting initiation interval is the maximum of RecMII and ResMII
+    II = std::max(RecMII, ResMII);
+    
+    //Print out II, RecMII, and ResMII
+    DEBUG(std::cerr << "II starts out as " << II << " ( RecMII=" << RecMII << "and ResMII=" << ResMII << "\n");
+    
+    //Calculate Node Properties
+    calculateNodeAttributes(MSG, ResMII);
+    
+    //Dump node properties if in debug mode
+    DEBUG(for(std::map<MSchedGraphNode*, MSNodeAttributes>::iterator I =  nodeToAttributesMap.begin(), 
+		E = nodeToAttributesMap.end(); I !=E; ++I) {
+      std::cerr << "Node: " << *(I->first) << " ASAP: " << I->second.ASAP << " ALAP: " 
+		<< I->second.ALAP << " MOB: " << I->second.MOB << " Depth: " << I->second.depth 
+		<< " Height: " << I->second.height << "\n";
+    });
+    
+    //Put nodes in order to schedule them
+    computePartialOrder();
+    
+    //Dump out partial order
+    DEBUG(for(std::vector<std::vector<MSchedGraphNode*> >::iterator I = partialOrder.begin(), 
+		E = partialOrder.end(); I !=E; ++I) {
+      std::cerr << "Start set in PO\n";
+      for(std::vector<MSchedGraphNode*>::iterator J = I->begin(), JE = I->end(); J != JE; ++J)
+	std::cerr << "PO:" << **J << "\n";
+    });
+    
+    //Place nodes in final order
+    orderNodes();
+    
+    //Dump out order of nodes
+    DEBUG(for(std::vector<MSchedGraphNode*>::iterator I = FinalNodeOrder.begin(), E = FinalNodeOrder.end(); I != E; ++I) {
+	  std::cerr << "FO:" << **I << "\n";
+    });
+    
+    //Finally schedule nodes
+    computeSchedule();
+    
+    //Print out final schedule
+    DEBUG(schedule.print(std::cerr));
+    
+
+    //Final scheduling step is to reconstruct the loop
+    reconstructLoop(*BI);
+    
+    //Print out new loop
+    
+    
+    //Clear out our maps for the next basic block that is processed
+    nodeToAttributesMap.clear();
+    partialOrder.clear();
+    recurrenceList.clear();
+    FinalNodeOrder.clear();
+    schedule.clear();
+
+    //Clean up. Nuke old MachineBB and llvmBB
+    //BasicBlock *llvmBB = (BasicBlock*) (*BI)->getBasicBlock();
+    //Function *parent = (Function*) llvmBB->getParent();
+    //Should't std::find work??
+    //parent->getBasicBlockList().erase(std::find(parent->getBasicBlockList().begin(), parent->getBasicBlockList().end(), *llvmBB));
+    //parent->getBasicBlockList().erase(llvmBB);
+    
+    //delete(llvmBB);
+    //delete(*BI);
+  }
+  
+ 
+  return Changed;
+}
+
+
+/// This function checks if a Machine Basic Block is valid for modulo
+/// scheduling. This means that it has no control flow (if/else or
+/// calls) in the block.  Currently ModuloScheduling only works on
+/// single basic block loops.
+bool ModuloSchedulingPass::MachineBBisValid(const MachineBasicBlock *BI) {
+
+  bool isLoop = false;
+  
+  //Check first if its a valid loop
+  for(succ_const_iterator I = succ_begin(BI->getBasicBlock()), 
+	E = succ_end(BI->getBasicBlock()); I != E; ++I) {
+    if (*I == BI->getBasicBlock())    // has single block loop
+      isLoop = true;
+  }
+  
+  if(!isLoop)
+    return false;
+    
+  //Get Target machine instruction info
+  const TargetInstrInfo *TMI = target.getInstrInfo();
+    
+  //Check each instruction and look for calls
+  for(MachineBasicBlock::const_iterator I = BI->begin(), E = BI->end(); I != E; ++I) {
+    //Get opcode to check instruction type
+    MachineOpCode OC = I->getOpcode();
+    if(TMI->isCall(OC))
+      return false;
+ 
+  }
+  return true;
+}
+
+//ResMII is calculated by determining the usage count for each resource
+//and using the maximum.
+//FIXME: In future there should be a way to get alternative resources
+//for each instruction
+int ModuloSchedulingPass::calculateResMII(const MachineBasicBlock *BI) {
+  
+  const TargetInstrInfo *mii = target.getInstrInfo();
+  const TargetSchedInfo *msi = target.getSchedInfo();
+
+  int ResMII = 0;
+  
+  //Map to keep track of usage count of each resource
+  std::map<unsigned, unsigned> resourceUsageCount;
+
+  for(MachineBasicBlock::const_iterator I = BI->begin(), E = BI->end(); I != E; ++I) {
+
+    //Get resource usage for this instruction
+    InstrRUsage rUsage = msi->getInstrRUsage(I->getOpcode());
+    std::vector<std::vector<resourceId_t> > resources = rUsage.resourcesByCycle;
+
+    //Loop over resources in each cycle and increments their usage count
+    for(unsigned i=0; i < resources.size(); ++i)
+      for(unsigned j=0; j < resources[i].size(); ++j) {
+	if( resourceUsageCount.find(resources[i][j]) == resourceUsageCount.end()) {
+	  resourceUsageCount[resources[i][j]] = 1;
+	}
+	else {
+	  resourceUsageCount[resources[i][j]] =  resourceUsageCount[resources[i][j]] + 1;
+	}
+      }
+  }
+
+  //Find maximum usage count
+  
+  //Get max number of instructions that can be issued at once. (FIXME)
+  int issueSlots = msi->maxNumIssueTotal;
+
+  for(std::map<unsigned,unsigned>::iterator RB = resourceUsageCount.begin(), RE = resourceUsageCount.end(); RB != RE; ++RB) {
+    
+    //Get the total number of the resources in our cpu
+    int resourceNum = CPUResource::getCPUResource(RB->first)->maxNumUsers;
+    
+    //Get total usage count for this resources
+    unsigned usageCount = RB->second;
+    
+    //Divide the usage count by either the max number we can issue or the number of
+    //resources (whichever is its upper bound)
+    double finalUsageCount;
+    if( resourceNum <= issueSlots)
+      finalUsageCount = ceil(1.0 * usageCount / resourceNum);
+    else
+      finalUsageCount = ceil(1.0 * usageCount / issueSlots);
+    
+    
+    //Only keep track of the max
+    ResMII = std::max( (int) finalUsageCount, ResMII);
+
+  }
+
+  return ResMII;
+
+}
+
+/// calculateRecMII - Calculates the value of the highest recurrence
+/// By value we mean the total latency
+int ModuloSchedulingPass::calculateRecMII(MSchedGraph *graph, int MII) {
+  std::vector<MSchedGraphNode*> vNodes;
+  //Loop over all nodes in the graph
+  for(MSchedGraph::iterator I = graph->begin(), E = graph->end(); I != E; ++I) {
+    findAllReccurrences(I->second, vNodes, MII);
+    vNodes.clear();
+  }
+
+  int RecMII = 0;
+  
+  for(std::set<std::pair<int, std::vector<MSchedGraphNode*> > >::iterator I = recurrenceList.begin(), E=recurrenceList.end(); I !=E; ++I) {
+    DEBUG(for(std::vector<MSchedGraphNode*>::const_iterator N = I->second.begin(), NE = I->second.end(); N != NE; ++N) {
+      std::cerr << **N << "\n";
+    });
+    RecMII = std::max(RecMII, I->first);
+  }
+    
+  return MII;
+}
+
+/// calculateNodeAttributes - The following properties are calculated for
+/// each node in the dependence graph: ASAP, ALAP, Depth, Height, and
+/// MOB.
+void ModuloSchedulingPass::calculateNodeAttributes(MSchedGraph *graph, int MII) {
+
+  //Loop over the nodes and add them to the map
+  for(MSchedGraph::iterator I = graph->begin(), E = graph->end(); I != E; ++I) {
+    //Assert if its already in the map
+    assert(nodeToAttributesMap.find(I->second) == nodeToAttributesMap.end() && "Node attributes are already in the map");
+    
+    //Put into the map with default attribute values
+    nodeToAttributesMap[I->second] = MSNodeAttributes();
+  }
+
+  //Create set to deal with reccurrences
+  std::set<MSchedGraphNode*> visitedNodes;
+  
+  //Now Loop over map and calculate the node attributes
+  for(std::map<MSchedGraphNode*, MSNodeAttributes>::iterator I = nodeToAttributesMap.begin(), E = nodeToAttributesMap.end(); I != E; ++I) {
+    calculateASAP(I->first, MII, (MSchedGraphNode*) 0);
+    visitedNodes.clear();
+  }
+  
+  int maxASAP = findMaxASAP();
+  //Calculate ALAP which depends on ASAP being totally calculated
+  for(std::map<MSchedGraphNode*, MSNodeAttributes>::iterator I = nodeToAttributesMap.begin(), E = nodeToAttributesMap.end(); I != E; ++I) {
+    calculateALAP(I->first, MII, maxASAP, (MSchedGraphNode*) 0);
+    visitedNodes.clear();
+  }
+
+  //Calculate MOB which depends on ASAP being totally calculated, also do depth and height
+  for(std::map<MSchedGraphNode*, MSNodeAttributes>::iterator I = nodeToAttributesMap.begin(), E = nodeToAttributesMap.end(); I != E; ++I) {
+    (I->second).MOB = std::max(0,(I->second).ALAP - (I->second).ASAP);
+   
+    DEBUG(std::cerr << "MOB: " << (I->second).MOB << " (" << *(I->first) << ")\n");
+    calculateDepth(I->first, (MSchedGraphNode*) 0);
+    calculateHeight(I->first, (MSchedGraphNode*) 0);
+  }
+
+
+}
+
+/// ignoreEdge - Checks to see if this edge of a recurrence should be ignored or not
+bool ModuloSchedulingPass::ignoreEdge(MSchedGraphNode *srcNode, MSchedGraphNode *destNode) {
+  if(destNode == 0 || srcNode ==0)
+    return false;
+  
+  bool findEdge = edgesToIgnore.count(std::make_pair(srcNode, destNode->getInEdgeNum(srcNode)));
+  
+  return findEdge;
+}
+
+
+/// calculateASAP - Calculates the 
+int  ModuloSchedulingPass::calculateASAP(MSchedGraphNode *node, int MII, MSchedGraphNode *destNode) {
+    
+  DEBUG(std::cerr << "Calculating ASAP for " << *node << "\n");
+
+  //Get current node attributes
+  MSNodeAttributes &attributes = nodeToAttributesMap.find(node)->second;
+
+  if(attributes.ASAP != -1)
+    return attributes.ASAP;
+  
+  int maxPredValue = 0;
+  
+  //Iterate over all of the predecessors and find max
+  for(MSchedGraphNode::pred_iterator P = node->pred_begin(), E = node->pred_end(); P != E; ++P) {
+    
+    //Only process if we are not ignoring the edge
+    if(!ignoreEdge(*P, node)) {
+      int predASAP = -1;
+      predASAP = calculateASAP(*P, MII, node);
+    
+      assert(predASAP != -1 && "ASAP has not been calculated");
+      int iteDiff = node->getInEdge(*P).getIteDiff();
+      
+      int currentPredValue = predASAP + (*P)->getLatency() - (iteDiff * MII);
+      DEBUG(std::cerr << "pred ASAP: " << predASAP << ", iteDiff: " << iteDiff << ", PredLatency: " << (*P)->getLatency() << ", Current ASAP pred: " << currentPredValue << "\n");
+      maxPredValue = std::max(maxPredValue, currentPredValue);
+    }
+  }
+  
+  attributes.ASAP = maxPredValue;
+
+  DEBUG(std::cerr << "ASAP: " << attributes.ASAP << " (" << *node << ")\n");
+  
+  return maxPredValue;
+}
+
+
+int ModuloSchedulingPass::calculateALAP(MSchedGraphNode *node, int MII, 
+					int maxASAP, MSchedGraphNode *srcNode) {
+  
+  DEBUG(std::cerr << "Calculating ALAP for " << *node << "\n");
+  
+  MSNodeAttributes &attributes = nodeToAttributesMap.find(node)->second;
+ 
+  if(attributes.ALAP != -1)
+    return attributes.ALAP;
+ 
+  if(node->hasSuccessors()) {
+    
+    //Trying to deal with the issue where the node has successors, but
+    //we are ignoring all of the edges to them. So this is my hack for
+    //now.. there is probably a more elegant way of doing this (FIXME)
+    bool processedOneEdge = false;
+
+    //FIXME, set to something high to start
+    int minSuccValue = 9999999;
+    
+    //Iterate over all of the predecessors and fine max
+    for(MSchedGraphNode::succ_iterator P = node->succ_begin(), 
+	  E = node->succ_end(); P != E; ++P) {
+      
+      //Only process if we are not ignoring the edge
+      if(!ignoreEdge(node, *P)) {
+	processedOneEdge = true;
+	int succALAP = -1;
+	succALAP = calculateALAP(*P, MII, maxASAP, node);
+	
+	assert(succALAP != -1 && "Successors ALAP should have been caclulated");
+	
+	int iteDiff = P.getEdge().getIteDiff();
+	
+	int currentSuccValue = succALAP - node->getLatency() + iteDiff * MII;
+	
+	DEBUG(std::cerr << "succ ALAP: " << succALAP << ", iteDiff: " << iteDiff << ", SuccLatency: " << (*P)->getLatency() << ", Current ALAP succ: " << currentSuccValue << "\n");
+
+	minSuccValue = std::min(minSuccValue, currentSuccValue);
+      }
+    }
+    
+    if(processedOneEdge)
+    	attributes.ALAP = minSuccValue;
+    
+    else
+      attributes.ALAP = maxASAP;
+  }
+  else
+    attributes.ALAP = maxASAP;
+
+  DEBUG(std::cerr << "ALAP: " << attributes.ALAP << " (" << *node << ")\n");
+
+  if(attributes.ALAP < 0)
+    attributes.ALAP = 0;
+
+  return attributes.ALAP;
+}
+
+int ModuloSchedulingPass::findMaxASAP() {
+  int maxASAP = 0;
+
+  for(std::map<MSchedGraphNode*, MSNodeAttributes>::iterator I = nodeToAttributesMap.begin(),
+	E = nodeToAttributesMap.end(); I != E; ++I)
+    maxASAP = std::max(maxASAP, I->second.ASAP);
+  return maxASAP;
+}
+
+
+int ModuloSchedulingPass::calculateHeight(MSchedGraphNode *node,MSchedGraphNode *srcNode) {
+  
+  MSNodeAttributes &attributes = nodeToAttributesMap.find(node)->second;
+
+  if(attributes.height != -1)
+    return attributes.height;
+
+  int maxHeight = 0;
+    
+  //Iterate over all of the predecessors and find max
+  for(MSchedGraphNode::succ_iterator P = node->succ_begin(), 
+	E = node->succ_end(); P != E; ++P) {
+    
+    
+    if(!ignoreEdge(node, *P)) {
+      int succHeight = calculateHeight(*P, node);
+
+      assert(succHeight != -1 && "Successors Height should have been caclulated");
+
+      int currentHeight = succHeight + node->getLatency();
+      maxHeight = std::max(maxHeight, currentHeight);
+    }
+  }
+  attributes.height = maxHeight;
+  DEBUG(std::cerr << "Height: " << attributes.height << " (" << *node << ")\n");
+  return maxHeight;
+}
+
+
+int ModuloSchedulingPass::calculateDepth(MSchedGraphNode *node, 
+					  MSchedGraphNode *destNode) {
+
+  MSNodeAttributes &attributes = nodeToAttributesMap.find(node)->second;
+
+  if(attributes.depth != -1)
+    return attributes.depth;
+
+  int maxDepth = 0;
+      
+  //Iterate over all of the predecessors and fine max
+  for(MSchedGraphNode::pred_iterator P = node->pred_begin(), E = node->pred_end(); P != E; ++P) {
+
+    if(!ignoreEdge(*P, node)) {
+      int predDepth = -1;
+      predDepth = calculateDepth(*P, node);
+      
+      assert(predDepth != -1 && "Predecessors ASAP should have been caclulated");
+
+      int currentDepth = predDepth + (*P)->getLatency();
+      maxDepth = std::max(maxDepth, currentDepth);
+    }
+  }
+  attributes.depth = maxDepth;
+  
+  DEBUG(std::cerr << "Depth: " << attributes.depth << " (" << *node << "*)\n");
+  return maxDepth;
+}
+
+
+
+void ModuloSchedulingPass::addReccurrence(std::vector<MSchedGraphNode*> &recurrence, int II, MSchedGraphNode *srcBENode, MSchedGraphNode *destBENode) {
+  //Check to make sure that this recurrence is unique
+  bool same = false;
+
+
+  //Loop over all recurrences already in our list
+  for(std::set<std::pair<int, std::vector<MSchedGraphNode*> > >::iterator R = recurrenceList.begin(), RE = recurrenceList.end(); R != RE; ++R) {
+    
+    bool all_same = true;
+     //First compare size
+    if(R->second.size() == recurrence.size()) {
+      
+      for(std::vector<MSchedGraphNode*>::const_iterator node = R->second.begin(), end = R->second.end(); node != end; ++node) {
+	if(std::find(recurrence.begin(), recurrence.end(), *node) == recurrence.end()) {
+	  all_same = all_same && false;
+	  break;
+	}
+	else
+	  all_same = all_same && true;
+      }
+      if(all_same) {
+	same = true;
+	break;
+      }
+    }
+  }
+  
+  if(!same) {
+    srcBENode = recurrence.back();
+    destBENode = recurrence.front();
+    
+    //FIXME
+    if(destBENode->getInEdge(srcBENode).getIteDiff() == 0) {
+      //DEBUG(std::cerr << "NOT A BACKEDGE\n");
+      //find actual backedge HACK HACK 
+      for(unsigned i=0; i< recurrence.size()-1; ++i) {
+	if(recurrence[i+1]->getInEdge(recurrence[i]).getIteDiff() == 1) {
+	  srcBENode = recurrence[i];
+	  destBENode = recurrence[i+1];
+	  break;
+	}
+	  
+      }
+      
+    }
+    DEBUG(std::cerr << "Back Edge to Remove: " << *srcBENode << " to " << *destBENode << "\n");
+    edgesToIgnore.insert(std::make_pair(srcBENode, destBENode->getInEdgeNum(srcBENode)));
+    recurrenceList.insert(std::make_pair(II, recurrence));
+  }
+  
+}
+
+void ModuloSchedulingPass::findAllReccurrences(MSchedGraphNode *node, 
+					       std::vector<MSchedGraphNode*> &visitedNodes,
+					       int II) {
+
+  if(std::find(visitedNodes.begin(), visitedNodes.end(), node) != visitedNodes.end()) {
+    std::vector<MSchedGraphNode*> recurrence;
+    bool first = true;
+    int delay = 0;
+    int distance = 0;
+    int RecMII = II; //Starting value
+    MSchedGraphNode *last = node;
+    MSchedGraphNode *srcBackEdge = 0;
+    MSchedGraphNode *destBackEdge = 0;
+    
+
+
+    for(std::vector<MSchedGraphNode*>::iterator I = visitedNodes.begin(), E = visitedNodes.end();
+	I !=E; ++I) {
+
+      if(*I == node) 
+	first = false;
+      if(first)
+	continue;
+
+      delay = delay + (*I)->getLatency();
+
+      if(*I != node) {
+	int diff = (*I)->getInEdge(last).getIteDiff();
+	distance += diff;
+	if(diff > 0) {
+	  srcBackEdge = last;
+	  destBackEdge = *I;
+	}
+      }
+
+      recurrence.push_back(*I);
+      last = *I;
+    }
+
+
+      
+    //Get final distance calc
+    distance += node->getInEdge(last).getIteDiff();
+   
+
+    //Adjust II until we get close to the inequality delay - II*distance <= 0
+    
+    int value = delay-(RecMII * distance);
+    int lastII = II;
+    while(value <= 0) {
+      
+      lastII = RecMII;
+      RecMII--;
+      value = delay-(RecMII * distance);
+    }
+    
+    
+    DEBUG(std::cerr << "Final II for this recurrence: " << lastII << "\n");
+    addReccurrence(recurrence, lastII, srcBackEdge, destBackEdge);
+    assert(distance != 0 && "Recurrence distance should not be zero");
+    return;
+  }
+
+  for(MSchedGraphNode::succ_iterator I = node->succ_begin(), E = node->succ_end(); I != E; ++I) {
+    visitedNodes.push_back(node);
+    findAllReccurrences(*I, visitedNodes, II);
+    visitedNodes.pop_back();
+  }
+}
+
+
+
+
+
+void ModuloSchedulingPass::computePartialOrder() {
+  
+  
+  //Loop over all recurrences and add to our partial order
+  //be sure to remove nodes that are already in the partial order in
+  //a different recurrence and don't add empty recurrences.
+  for(std::set<std::pair<int, std::vector<MSchedGraphNode*> > >::reverse_iterator I = recurrenceList.rbegin(), E=recurrenceList.rend(); I !=E; ++I) {
+    
+    //Add nodes that connect this recurrence to the previous recurrence
+    
+    //If this is the first recurrence in the partial order, add all predecessors
+    for(std::vector<MSchedGraphNode*>::const_iterator N = I->second.begin(), NE = I->second.end(); N != NE; ++N) {
+
+    }
+
+
+    std::vector<MSchedGraphNode*> new_recurrence;
+    //Loop through recurrence and remove any nodes already in the partial order
+    for(std::vector<MSchedGraphNode*>::const_iterator N = I->second.begin(), NE = I->second.end(); N != NE; ++N) {
+      bool found = false;
+      for(std::vector<std::vector<MSchedGraphNode*> >::iterator PO = partialOrder.begin(), PE = partialOrder.end(); PO != PE; ++PO) {
+	if(std::find(PO->begin(), PO->end(), *N) != PO->end())
+	  found = true;
+      }
+      if(!found) {
+	new_recurrence.push_back(*N);
+	 
+	if(partialOrder.size() == 0)
+	  //For each predecessors, add it to this recurrence ONLY if it is not already in it
+	  for(MSchedGraphNode::pred_iterator P = (*N)->pred_begin(), 
+		PE = (*N)->pred_end(); P != PE; ++P) {
+	    
+	    //Check if we are supposed to ignore this edge or not
+	    if(!ignoreEdge(*P, *N))
+	      //Check if already in this recurrence
+	      if(std::find(I->second.begin(), I->second.end(), *P) == I->second.end()) {
+		//Also need to check if in partial order
+		bool predFound = false;
+		for(std::vector<std::vector<MSchedGraphNode*> >::iterator PO = partialOrder.begin(), PEND = partialOrder.end(); PO != PEND; ++PO) {
+		  if(std::find(PO->begin(), PO->end(), *P) != PO->end())
+		    predFound = true;
+		}
+		
+		if(!predFound)
+		  if(std::find(new_recurrence.begin(), new_recurrence.end(), *P) == new_recurrence.end())
+		     new_recurrence.push_back(*P);
+		
+	      }
+	  }
+      }
+    }
+
+        
+    if(new_recurrence.size() > 0)
+      partialOrder.push_back(new_recurrence);
+  }
+  
+  //Add any nodes that are not already in the partial order
+  std::vector<MSchedGraphNode*> lastNodes;
+  for(std::map<MSchedGraphNode*, MSNodeAttributes>::iterator I = nodeToAttributesMap.begin(), E = nodeToAttributesMap.end(); I != E; ++I) {
+    bool found = false;
+    //Check if its already in our partial order, if not add it to the final vector
+    for(std::vector<std::vector<MSchedGraphNode*> >::iterator PO = partialOrder.begin(), PE = partialOrder.end(); PO != PE; ++PO) {
+      if(std::find(PO->begin(), PO->end(), I->first) != PO->end())
+	found = true;
+    }
+    if(!found)
+      lastNodes.push_back(I->first);
+  }
+
+  if(lastNodes.size() > 0)
+    partialOrder.push_back(lastNodes);
+  
+}
+
+
+void ModuloSchedulingPass::predIntersect(std::vector<MSchedGraphNode*> &CurrentSet, std::vector<MSchedGraphNode*> &IntersectResult) {
+  
+  //Sort CurrentSet so we can use lowerbound
+  std::sort(CurrentSet.begin(), CurrentSet.end());
+  
+  for(unsigned j=0; j < FinalNodeOrder.size(); ++j) {
+    for(MSchedGraphNode::pred_iterator P = FinalNodeOrder[j]->pred_begin(), 
+	  E = FinalNodeOrder[j]->pred_end(); P != E; ++P) {
+   
+      //Check if we are supposed to ignore this edge or not
+      if(ignoreEdge(*P,FinalNodeOrder[j]))
+	continue;
+	 
+      if(std::find(CurrentSet.begin(), 
+		     CurrentSet.end(), *P) != CurrentSet.end())
+	if(std::find(FinalNodeOrder.begin(), FinalNodeOrder.end(), *P) == FinalNodeOrder.end())
+	  IntersectResult.push_back(*P);
+    }
+  } 
+}
+
+void ModuloSchedulingPass::succIntersect(std::vector<MSchedGraphNode*> &CurrentSet, std::vector<MSchedGraphNode*> &IntersectResult) {
+
+  //Sort CurrentSet so we can use lowerbound
+  std::sort(CurrentSet.begin(), CurrentSet.end());
+  
+  for(unsigned j=0; j < FinalNodeOrder.size(); ++j) {
+    for(MSchedGraphNode::succ_iterator P = FinalNodeOrder[j]->succ_begin(), 
+	  E = FinalNodeOrder[j]->succ_end(); P != E; ++P) {
+
+      //Check if we are supposed to ignore this edge or not
+      if(ignoreEdge(FinalNodeOrder[j],*P))
+	continue;
+
+      if(std::find(CurrentSet.begin(), 
+		     CurrentSet.end(), *P) != CurrentSet.end())
+	if(std::find(FinalNodeOrder.begin(), FinalNodeOrder.end(), *P) == FinalNodeOrder.end())
+	  IntersectResult.push_back(*P);
+    }
+  }
+}
+
+void dumpIntersection(std::vector<MSchedGraphNode*> &IntersectCurrent) {
+  std::cerr << "Intersection (";
+  for(std::vector<MSchedGraphNode*>::iterator I = IntersectCurrent.begin(), E = IntersectCurrent.end(); I != E; ++I)
+    std::cerr << **I << ", ";
+  std::cerr << ")\n";
+}
+
+
+
+void ModuloSchedulingPass::orderNodes() {
+  
+  int BOTTOM_UP = 0;
+  int TOP_DOWN = 1;
+
+  //Set default order
+  int order = BOTTOM_UP;
+
+
+  //Loop over all the sets and place them in the final node order
+  for(std::vector<std::vector<MSchedGraphNode*> >::iterator CurrentSet = partialOrder.begin(), E= partialOrder.end(); CurrentSet != E; ++CurrentSet) {
+
+    DEBUG(std::cerr << "Processing set in S\n");
+    DEBUG(dumpIntersection(*CurrentSet));
+
+    //Result of intersection
+    std::vector<MSchedGraphNode*> IntersectCurrent;
+
+    predIntersect(*CurrentSet, IntersectCurrent);
+
+    //If the intersection of predecessor and current set is not empty
+    //sort nodes bottom up
+    if(IntersectCurrent.size() != 0) {
+      DEBUG(std::cerr << "Final Node Order Predecessors and Current Set interesection is NOT empty\n");
+      order = BOTTOM_UP;
+    }
+    //If empty, use successors
+    else {
+      DEBUG(std::cerr << "Final Node Order Predecessors and Current Set interesection is empty\n");
+
+      succIntersect(*CurrentSet, IntersectCurrent);
+
+      //sort top-down
+      if(IntersectCurrent.size() != 0) {
+	 DEBUG(std::cerr << "Final Node Order Successors and Current Set interesection is NOT empty\n");
+	order = TOP_DOWN;
+      }
+      else {
+	DEBUG(std::cerr << "Final Node Order Successors and Current Set interesection is empty\n");
+	//Find node with max ASAP in current Set
+	MSchedGraphNode *node;
+	int maxASAP = 0;
+	DEBUG(std::cerr << "Using current set of size " << CurrentSet->size() << "to find max ASAP\n");
+	for(unsigned j=0; j < CurrentSet->size(); ++j) {
+	  //Get node attributes
+	  MSNodeAttributes nodeAttr= nodeToAttributesMap.find((*CurrentSet)[j])->second;
+	  //assert(nodeAttr != nodeToAttributesMap.end() && "Node not in attributes map!");
+	  DEBUG(std::cerr << "CurrentSet index " << j << "has ASAP: " << nodeAttr.ASAP << "\n");
+	  if(maxASAP < nodeAttr.ASAP) {
+	    maxASAP = nodeAttr.ASAP;
+	    node = (*CurrentSet)[j];
+	  }
+	}
+	assert(node != 0 && "In node ordering node should not be null");
+	IntersectCurrent.push_back(node);
+	order = BOTTOM_UP;
+      }
+    }
+      
+    //Repeat until all nodes are put into the final order from current set
+    while(IntersectCurrent.size() > 0) {
+
+      if(order == TOP_DOWN) {
+	DEBUG(std::cerr << "Order is TOP DOWN\n");
+
+	while(IntersectCurrent.size() > 0) {
+	  DEBUG(std::cerr << "Intersection is not empty, so find heighest height\n");
+	  
+	  int MOB = 0;
+	  int height = 0;
+	  MSchedGraphNode *highestHeightNode = IntersectCurrent[0];
+	  	  
+	  //Find node in intersection with highest heigh and lowest MOB
+	  for(std::vector<MSchedGraphNode*>::iterator I = IntersectCurrent.begin(), 
+		E = IntersectCurrent.end(); I != E; ++I) {
+	    
+	    //Get current nodes properties
+	    MSNodeAttributes nodeAttr= nodeToAttributesMap.find(*I)->second;
+
+	    if(height < nodeAttr.height) {
+	      highestHeightNode = *I;
+	      height = nodeAttr.height;
+	      MOB = nodeAttr.MOB;
+	    }
+	    else if(height ==  nodeAttr.height) {
+	      if(MOB > nodeAttr.height) {
+		highestHeightNode = *I;
+		height =  nodeAttr.height;
+		MOB = nodeAttr.MOB;
+	      }
+	    }
+	  }
+	  
+	  //Append our node with greatest height to the NodeOrder
+	  if(std::find(FinalNodeOrder.begin(), FinalNodeOrder.end(), highestHeightNode) == FinalNodeOrder.end()) {
+	    DEBUG(std::cerr << "Adding node to Final Order: " << *highestHeightNode << "\n");
+	    FinalNodeOrder.push_back(highestHeightNode);
+	  }
+
+	  //Remove V from IntersectOrder
+	  IntersectCurrent.erase(std::find(IntersectCurrent.begin(), 
+				      IntersectCurrent.end(), highestHeightNode));
+
+
+	  //Intersect V's successors with CurrentSet
+	  for(MSchedGraphNode::succ_iterator P = highestHeightNode->succ_begin(),
+		E = highestHeightNode->succ_end(); P != E; ++P) {
+	    //if(lower_bound(CurrentSet->begin(), 
+	    //	   CurrentSet->end(), *P) != CurrentSet->end()) {
+	    if(std::find(CurrentSet->begin(), CurrentSet->end(), *P) != CurrentSet->end()) {  
+	      if(ignoreEdge(highestHeightNode, *P))
+		continue;
+	      //If not already in Intersect, add
+	      if(std::find(IntersectCurrent.begin(), IntersectCurrent.end(), *P) == IntersectCurrent.end())
+		IntersectCurrent.push_back(*P);
+	    }
+	  }
+     	} //End while loop over Intersect Size
+
+	//Change direction
+	order = BOTTOM_UP;
+
+	//Reset Intersect to reflect changes in OrderNodes
+	IntersectCurrent.clear();
+	predIntersect(*CurrentSet, IntersectCurrent);
+	
+      } //End If TOP_DOWN
+	
+	//Begin if BOTTOM_UP
+      else {
+	DEBUG(std::cerr << "Order is BOTTOM UP\n");
+	while(IntersectCurrent.size() > 0) {
+	  DEBUG(std::cerr << "Intersection of size " << IntersectCurrent.size() << ", finding highest depth\n");
+
+	  //dump intersection
+	  DEBUG(dumpIntersection(IntersectCurrent));
+	  //Get node with highest depth, if a tie, use one with lowest
+	  //MOB
+	  int MOB = 0;
+	  int depth = 0;
+	  MSchedGraphNode *highestDepthNode = IntersectCurrent[0];
+	  
+	  for(std::vector<MSchedGraphNode*>::iterator I = IntersectCurrent.begin(), 
+		E = IntersectCurrent.end(); I != E; ++I) {
+	    //Find node attribute in graph
+	    MSNodeAttributes nodeAttr= nodeToAttributesMap.find(*I)->second;
+	    
+	    if(depth < nodeAttr.depth) {
+	      highestDepthNode = *I;
+	      depth = nodeAttr.depth;
+	      MOB = nodeAttr.MOB;
+	    }
+	    else if(depth == nodeAttr.depth) {
+	      if(MOB > nodeAttr.MOB) {
+		highestDepthNode = *I;
+		depth = nodeAttr.depth;
+		MOB = nodeAttr.MOB;
+	      }
+	    }
+	  }
+	  
+	  
+
+	  //Append highest depth node to the NodeOrder
+	   if(std::find(FinalNodeOrder.begin(), FinalNodeOrder.end(), highestDepthNode) == FinalNodeOrder.end()) {
+	     DEBUG(std::cerr << "Adding node to Final Order: " << *highestDepthNode << "\n");
+	     FinalNodeOrder.push_back(highestDepthNode);
+	   }
+	  //Remove heightestDepthNode from IntersectOrder
+	  IntersectCurrent.erase(std::find(IntersectCurrent.begin(), 
+				      IntersectCurrent.end(),highestDepthNode));
+	  
+
+	  //Intersect heightDepthNode's pred with CurrentSet
+	  for(MSchedGraphNode::pred_iterator P = highestDepthNode->pred_begin(), 
+		E = highestDepthNode->pred_end(); P != E; ++P) {
+	    //if(lower_bound(CurrentSet->begin(), 
+	    //	   CurrentSet->end(), *P) != CurrentSet->end()) {
+	    if(std::find(CurrentSet->begin(), CurrentSet->end(), *P) != CurrentSet->end()) {
+	    
+	      if(ignoreEdge(*P, highestDepthNode))
+		continue;
+	    
+	    //If not already in Intersect, add
+	    if(std::find(IntersectCurrent.begin(), 
+		      IntersectCurrent.end(), *P) == IntersectCurrent.end())
+		IntersectCurrent.push_back(*P);
+	    }
+	  }
+	  
+	} //End while loop over Intersect Size
+	
+	  //Change order
+	order = TOP_DOWN;
+	
+	//Reset IntersectCurrent to reflect changes in OrderNodes
+	IntersectCurrent.clear();
+	succIntersect(*CurrentSet, IntersectCurrent);
+	} //End if BOTTOM_DOWN
+	
+      DEBUG(std::cerr << "Current Intersection Size: " << IntersectCurrent.size() << "\n");
+    }
+    //End Wrapping while loop
+    DEBUG(std::cerr << "Ending Size of Current Set: " << CurrentSet->size() << "\n");  
+  }//End for over all sets of nodes
+  
+  //FIXME: As the algorithm stands it will NEVER add an instruction such as ba (with no
+  //data dependencies) to the final order. We add this manually. It will always be
+  //in the last set of S since its not part of a recurrence
+    //Loop over all the sets and place them in the final node order
+  std::vector<std::vector<MSchedGraphNode*> > ::reverse_iterator LastSet = partialOrder.rbegin();
+  for(std::vector<MSchedGraphNode*>::iterator CurrentNode = LastSet->begin(), LastNode = LastSet->end();
+      CurrentNode != LastNode; ++CurrentNode) {
+    if((*CurrentNode)->getInst()->getOpcode() == V9::BA)
+      FinalNodeOrder.push_back(*CurrentNode);
+  }
+  //Return final Order
+  //return FinalNodeOrder;
+}
+
+void ModuloSchedulingPass::computeSchedule() {
+
+  bool success = false;
+  
+  while(!success) {
+    
+    //Loop over the final node order and process each node
+    for(std::vector<MSchedGraphNode*>::iterator I = FinalNodeOrder.begin(), 
+	  E = FinalNodeOrder.end(); I != E; ++I) {
+      
+      //CalculateEarly and Late start
+      int EarlyStart = -1;
+      int LateStart = 99999; //Set to something higher then we would ever expect (FIXME)
+      bool hasSucc = false;
+      bool hasPred = false;
+      
+      if(!(*I)->isBranch()) {
+	//Loop over nodes in the schedule and determine if they are predecessors
+	//or successors of the node we are trying to schedule
+	for(MSSchedule::schedule_iterator nodesByCycle = schedule.begin(), nodesByCycleEnd = schedule.end(); 
+	    nodesByCycle != nodesByCycleEnd; ++nodesByCycle) {
+	  
+	  //For this cycle, get the vector of nodes schedule and loop over it
+	  for(std::vector<MSchedGraphNode*>::iterator schedNode = nodesByCycle->second.begin(), SNE = nodesByCycle->second.end(); schedNode != SNE; ++schedNode) {
+	    
+	    if((*I)->isPredecessor(*schedNode)) {
+	      if(!ignoreEdge(*schedNode, *I)) {
+		int diff = (*I)->getInEdge(*schedNode).getIteDiff();
+		int ES_Temp = nodesByCycle->first + (*schedNode)->getLatency() - diff * II;
+		DEBUG(std::cerr << "Diff: " << diff << " Cycle: " << nodesByCycle->first << "\n");
+		DEBUG(std::cerr << "Temp EarlyStart: " << ES_Temp << " Prev EarlyStart: " << EarlyStart << "\n");
+		EarlyStart = std::max(EarlyStart, ES_Temp);
+		hasPred = true;
+	      }
+	    }
+	    if((*I)->isSuccessor(*schedNode)) {
+	      if(!ignoreEdge(*I,*schedNode)) {
+		int diff = (*schedNode)->getInEdge(*I).getIteDiff();
+		int LS_Temp = nodesByCycle->first - (*I)->getLatency() + diff * II;
+		DEBUG(std::cerr << "Diff: " << diff << " Cycle: " << nodesByCycle->first << "\n");
+		DEBUG(std::cerr << "Temp LateStart: " << LS_Temp << " Prev LateStart: " << LateStart << "\n");
+		LateStart = std::min(LateStart, LS_Temp);
+		hasSucc = true;
+	      }
+	    }
+	  }
+	}
+      }
+      else {
+	//WARNING: HACK! FIXME!!!!
+	if((*I)->getInst()->getOpcode() == V9::BA) {
+	  EarlyStart = II-1;
+	  LateStart = II-1;
+	}
+	else {
+	  EarlyStart = II-1;
+	  LateStart = II-1;
+	  assert( (EarlyStart >= 0) && (LateStart >=0) && "EarlyStart and LateStart must be greater then 0"); 
+	}
+	hasPred = 1;
+	hasSucc = 1;
+      }
+ 
+      
+      DEBUG(std::cerr << "Has Successors: " << hasSucc << ", Has Pred: " << hasPred << "\n");
+      DEBUG(std::cerr << "EarlyStart: " << EarlyStart << ", LateStart: " << LateStart << "\n");
+
+      //Check if the node has no pred or successors and set Early Start to its ASAP
+      if(!hasSucc && !hasPred)
+	EarlyStart = nodeToAttributesMap.find(*I)->second.ASAP;
+      
+      //Now, try to schedule this node depending upon its pred and successor in the schedule
+      //already
+      if(!hasSucc && hasPred)
+	success = scheduleNode(*I, EarlyStart, (EarlyStart + II -1));
+      else if(!hasPred && hasSucc)
+	success = scheduleNode(*I, LateStart, (LateStart - II +1));
+      else if(hasPred && hasSucc)
+	success = scheduleNode(*I, EarlyStart, std::min(LateStart, (EarlyStart + II -1)));
+      else
+	success = scheduleNode(*I, EarlyStart, EarlyStart + II - 1);
+      
+      if(!success) {
+	++II; 
+	schedule.clear();
+	break;
+      }
+     
+    }
+
+    DEBUG(std::cerr << "Constructing Kernel\n");
+    success = schedule.constructKernel(II);
+    if(!success) {
+      ++II;
+      schedule.clear();
+    }
+  } 
+}
+
+
+bool ModuloSchedulingPass::scheduleNode(MSchedGraphNode *node, 
+				      int start, int end) {
+  bool success = false;
+
+  DEBUG(std::cerr << *node << " (Start Cycle: " << start << ", End Cycle: " << end << ")\n");
+
+  //Make sure start and end are not negative
+  if(start < 0)
+    start = 0;
+  if(end < 0)
+    end = 0;
+
+  bool forward = true;
+  if(start > end)
+    forward = false;
+
+  bool increaseSC = true;
+  int cycle = start ;
+
+
+  while(increaseSC) {
+    
+    increaseSC = false;
+
+    increaseSC = schedule.insert(node, cycle);
+    
+    if(!increaseSC) 
+      return true;
+
+    //Increment cycle to try again
+    if(forward) {
+      ++cycle;
+      DEBUG(std::cerr << "Increase cycle: " << cycle << "\n");
+      if(cycle > end)
+	return false;
+    }
+    else {
+      --cycle;
+      DEBUG(std::cerr << "Decrease cycle: " << cycle << "\n");
+      if(cycle < end)
+	return false;
+    }
+  }
+
+  return success;
+}
+
+void ModuloSchedulingPass::writePrologues(std::vector<MachineBasicBlock *> &prologues, MachineBasicBlock *origBB, std::vector<BasicBlock*> &llvm_prologues, std::map<const Value*, std::pair<const MSchedGraphNode*, int> > &valuesToSave, std::map<Value*, std::map<int, Value*> > &newValues, std::map<Value*, MachineBasicBlock*> &newValLocation) {
+
+  //Keep a map to easily know whats in the kernel
+  std::map<int, std::set<const MachineInstr*> > inKernel;
+  int maxStageCount = 0;
+
+  MSchedGraphNode *branch = 0;
+  MSchedGraphNode *BAbranch = 0;
+
+  for(MSSchedule::kernel_iterator I = schedule.kernel_begin(), E = schedule.kernel_end(); I != E; ++I) {
+    maxStageCount = std::max(maxStageCount, I->second);
+    
+    //Ignore the branch, we will handle this separately
+    if(I->first->isBranch()) {
+      if (I->first->getInst()->getOpcode() == V9::BA)
+	BAbranch = I->first;
+      else
+	branch = I->first;
+      continue;
+    }
+
+    //Put int the map so we know what instructions in each stage are in the kernel
+    DEBUG(std::cerr << "Inserting instruction " << *(I->first->getInst()) << " into map at stage " << I->second << "\n");
+    inKernel[I->second].insert(I->first->getInst());
+  }
+
+  //Get target information to look at machine operands
+  const TargetInstrInfo *mii = target.getInstrInfo();
+
+ //Now write the prologues
+  for(int i = 0; i < maxStageCount; ++i) {
+    BasicBlock *llvmBB = new BasicBlock("PROLOGUE", (Function*) (origBB->getBasicBlock()->getParent()));
+    MachineBasicBlock *machineBB = new MachineBasicBlock(llvmBB);
+  
+    DEBUG(std::cerr << "i=" << i << "\n");
+    for(int j = 0; j <= i; ++j) {
+      for(MachineBasicBlock::const_iterator MI = origBB->begin(), ME = origBB->end(); ME != MI; ++MI) {
+	if(inKernel[j].count(&*MI)) {
+	  MachineInstr *instClone = MI->clone();
+	  machineBB->push_back(instClone);
+	  
+	  DEBUG(std::cerr << "Cloning: " << *MI << "\n");
+
+	  Instruction *tmp;
+
+	  //After cloning, we may need to save the value that this instruction defines
+	  for(unsigned opNum=0; opNum < MI->getNumOperands(); ++opNum) {
+	    //get machine operand
+	    const MachineOperand &mOp = instClone->getOperand(opNum);
+	    if(mOp.getType() == MachineOperand::MO_VirtualRegister && mOp.isDef()) {
+
+	      //Check if this is a value we should save
+	      if(valuesToSave.count(mOp.getVRegValue())) {
+		//Save copy in tmpInstruction
+		tmp = new TmpInstruction(mOp.getVRegValue());
+		
+		DEBUG(std::cerr << "Value: " << *(mOp.getVRegValue()) << " New Value: " << *tmp << " Stage: " << i << "\n");
+		
+		newValues[mOp.getVRegValue()][i]= tmp;
+		newValLocation[tmp] = machineBB;
+
+		DEBUG(std::cerr << "Machine Instr Operands: " << *(mOp.getVRegValue()) << ", 0, " << *tmp << "\n");
+		
+		//Create machine instruction and put int machineBB
+		MachineInstr *saveValue = BuildMI(machineBB, V9::ORr, 3).addReg(mOp.getVRegValue()).addImm(0).addRegDef(tmp);
+		
+		DEBUG(std::cerr << "Created new machine instr: " << *saveValue << "\n");
+	      }
+	    }
+
+	    //We may also need to update the value that we use if its from an earlier prologue
+	    if(j != 0) {
+	      if(mOp.getType() == MachineOperand::MO_VirtualRegister && mOp.isUse()) {
+		if(newValues.count(mOp.getVRegValue()))
+		  if(newValues[mOp.getVRegValue()].count(j-1)) {
+		    DEBUG(std::cerr << "Replaced this value: " << mOp.getVRegValue() << " With:" << (newValues[mOp.getVRegValue()][i-1]) << "\n");
+		    //Update the operand with the right value
+		    instClone->getOperand(opNum).setValueReg(newValues[mOp.getVRegValue()][i-1]);
+		  }
+	      }
+	    }
+	  }
+	}
+      }
+    }
+
+
+    //Stick in branch at the end
+    machineBB->push_back(branch->getInst()->clone());
+    
+    //Stick in BA branch at the end
+    machineBB->push_back(BAbranch->getInst()->clone());
+
+  (((MachineBasicBlock*)origBB)->getParent())->getBasicBlockList().push_back(machineBB);  
+    prologues.push_back(machineBB);
+    llvm_prologues.push_back(llvmBB);
+  }
+}
+
+void ModuloSchedulingPass::writeEpilogues(std::vector<MachineBasicBlock *> &epilogues, const MachineBasicBlock *origBB, std::vector<BasicBlock*> &llvm_epilogues, std::map<const Value*, std::pair<const MSchedGraphNode*, int> > &valuesToSave, std::map<Value*, std::map<int, Value*> > &newValues,std::map<Value*, MachineBasicBlock*> &newValLocation, std::map<Value*, std::map<int, Value*> > &kernelPHIs ) {
+  
+  std::map<int, std::set<const MachineInstr*> > inKernel;
+  
+  for(MSSchedule::kernel_iterator I = schedule.kernel_begin(), E = schedule.kernel_end(); I != E; ++I) {
+    
+    //Ignore the branch, we will handle this separately
+    if(I->first->isBranch())
+      continue;
+
+    //Put int the map so we know what instructions in each stage are in the kernel
+    inKernel[I->second].insert(I->first->getInst());
+  }
+
+  std::map<Value*, Value*> valPHIs;
+
+  //some debug stuff, will remove later
+  DEBUG(for(std::map<Value*, std::map<int, Value*> >::iterator V = newValues.begin(), E = newValues.end(); V !=E; ++V) {
+    std::cerr << "Old Value: " << *(V->first) << "\n";
+    for(std::map<int, Value*>::iterator I = V->second.begin(), IE = V->second.end(); I != IE; ++I)
+      std::cerr << "Stage: " << I->first << " Value: " << *(I->second) << "\n";
+  });
+
+  //some debug stuff, will remove later
+  DEBUG(for(std::map<Value*, std::map<int, Value*> >::iterator V = kernelPHIs.begin(), E = kernelPHIs.end(); V !=E; ++V) {
+    std::cerr << "Old Value: " << *(V->first) << "\n";
+    for(std::map<int, Value*>::iterator I = V->second.begin(), IE = V->second.end(); I != IE; ++I)
+      std::cerr << "Stage: " << I->first << " Value: " << *(I->second) << "\n";
+  });
+
+  //Now write the epilogues
+  for(int i = schedule.getMaxStage()-1; i >= 0; --i) {
+    BasicBlock *llvmBB = new BasicBlock("EPILOGUE", (Function*) (origBB->getBasicBlock()->getParent()));
+    MachineBasicBlock *machineBB = new MachineBasicBlock(llvmBB);
+   
+    DEBUG(std::cerr << " Epilogue #: " << i << "\n");
+
+
+
+
+     for(MachineBasicBlock::const_iterator MI = origBB->begin(), ME = origBB->end(); ME != MI; ++MI) {
+      for(int j=schedule.getMaxStage(); j > i; --j) {
+	if(inKernel[j].count(&*MI)) {
+	  DEBUG(std::cerr << "Cloning instruction " << *MI << "\n");
+	  MachineInstr *clone = MI->clone();
+	  
+	  //Update operands that need to use the result from the phi
+	  for(unsigned opNum=0; opNum < clone->getNumOperands(); ++opNum) {
+	    //get machine operand
+	    const MachineOperand &mOp = clone->getOperand(opNum);
+
+	  //If this is the last instructions for the max iterations ago, don't update operands
+	    if(j == schedule.getMaxStage() && (i == 0))
+	      continue;
+	    
+	    if((mOp.getType() == MachineOperand::MO_VirtualRegister && mOp.isUse())) {
+	      
+	      DEBUG(std::cerr << "Writing PHI for " << *(mOp.getVRegValue()) << "\n");
+	      
+	      //Quickly write appropriate phis for this operand
+	      if(newValues.count(mOp.getVRegValue())) {
+		if(newValues[mOp.getVRegValue()].count(i)) {
+		  Instruction *tmp = new TmpInstruction(newValues[mOp.getVRegValue()][i]);
+		  MachineInstr *saveValue = BuildMI(machineBB, V9::PHI, 3).addReg(newValues[mOp.getVRegValue()][i]).addReg(kernelPHIs[mOp.getVRegValue()][i]).addRegDef(tmp);
+		  DEBUG(std::cerr << "Resulting PHI: " << *saveValue << "\n");
+		  valPHIs[mOp.getVRegValue()] = tmp;
+		}
+	      }
+	      
+	      if(valPHIs.count(mOp.getVRegValue())) {
+		//Update the operand in the cloned instruction
+		clone->getOperand(opNum).setValueReg(valPHIs[mOp.getVRegValue()]); 
+	      }
+	    }
+	  }
+	  machineBB->push_back(clone);
+	}
+      }
+     }
+
+    (((MachineBasicBlock*)origBB)->getParent())->getBasicBlockList().push_back(machineBB);
+    epilogues.push_back(machineBB);
+    llvm_epilogues.push_back(llvmBB);
+  
+    DEBUG(std::cerr << "EPILOGUE #" << i << "\n");
+    DEBUG(machineBB->print(std::cerr));
+  }
+}
+
+void ModuloSchedulingPass::writeKernel(BasicBlock *llvmBB, MachineBasicBlock *machineBB, std::map<const Value*, std::pair<const MSchedGraphNode*, int> > &valuesToSave, std::map<Value*, std::map<int, Value*> > &newValues, std::map<Value*, MachineBasicBlock*> &newValLocation, std::map<Value*, std::map<int, Value*> > &kernelPHIs) {
+  
+  //Keep track of operands that are read and saved from a previous iteration. The new clone
+  //instruction will use the result of the phi instead.
+  std::map<Value*, Value*> finalPHIValue;
+  std::map<Value*, Value*> kernelValue;
+
+    //Create TmpInstructions for the final phis
+ for(MSSchedule::kernel_iterator I = schedule.kernel_begin(), E = schedule.kernel_end(); I != E; ++I) {
+
+   DEBUG(std::cerr << "Stage: " << I->second << " Inst: " << *(I->first->getInst()) << "\n";);
+
+   //Clone instruction
+   const MachineInstr *inst = I->first->getInst();
+   MachineInstr *instClone = inst->clone();
+
+   //Insert into machine basic block
+   machineBB->push_back(instClone);
+
+   
+   //Loop over Machine Operands
+   for(unsigned i=0; i < inst->getNumOperands(); ++i) {
+     //get machine operand
+     const MachineOperand &mOp = inst->getOperand(i);
+   
+     if(I->second != 0) {
+       if(mOp.getType() == MachineOperand::MO_VirtualRegister && mOp.isUse()) {
+
+	 //Check to see where this operand is defined if this instruction is from max stage
+	 if(I->second == schedule.getMaxStage()) {
+	   DEBUG(std::cerr << "VREG: " << *(mOp.getVRegValue()) << "\n");
+	 }
+
+	 //If its in the value saved, we need to create a temp instruction and use that instead
+	 if(valuesToSave.count(mOp.getVRegValue())) {
+	   TmpInstruction *tmp = new TmpInstruction(mOp.getVRegValue());
+	   
+	   //Update the operand in the cloned instruction
+	   instClone->getOperand(i).setValueReg(tmp);
+	   
+	   //save this as our final phi
+	   finalPHIValue[mOp.getVRegValue()] = tmp;
+	   newValLocation[tmp] = machineBB;
+	 }
+       }
+     }
+     if(I->second != schedule.getMaxStage()) {
+       if(mOp.getType() == MachineOperand::MO_VirtualRegister && mOp.isDef()) {
+	 if(valuesToSave.count(mOp.getVRegValue())) {
+	   
+	   TmpInstruction *tmp = new TmpInstruction(mOp.getVRegValue());
+	   
+	   //Create new machine instr and put in MBB
+	   MachineInstr *saveValue = BuildMI(machineBB, V9::ORr, 3).addReg(mOp.getVRegValue()).addImm(0).addRegDef(tmp);
+	   
+	   //Save for future cleanup
+	   kernelValue[mOp.getVRegValue()] = tmp;
+	   newValLocation[tmp] = machineBB;
+	   kernelPHIs[mOp.getVRegValue()][schedule.getMaxStage()-1] = tmp;
+	 }
+       }
+     }
+   }
+   
+ }
+
+  DEBUG(std::cerr << "KERNEL before PHIs\n");
+  DEBUG(machineBB->print(std::cerr));
+
+
+ //Loop over each value we need to generate phis for
+ for(std::map<Value*, std::map<int, Value*> >::iterator V = newValues.begin(), 
+       E = newValues.end(); V != E; ++V) {
+
+
+   DEBUG(std::cerr << "Writing phi for" << *(V->first));
+   DEBUG(std::cerr << "\nMap of Value* for this phi\n");
+   DEBUG(for(std::map<int, Value*>::iterator I = V->second.begin(), 
+	       IE = V->second.end(); I != IE; ++I) { 
+     std::cerr << "Stage: " << I->first;
+     std::cerr << " Value: " << *(I->second) << "\n";
+   });
+
+   //If we only have one current iteration live, its safe to set lastPhi = to kernel value
+   if(V->second.size() == 1) {
+     assert(kernelValue[V->first] != 0 && "Kernel value* must exist to create phi");
+     MachineInstr *saveValue = BuildMI(*machineBB, machineBB->begin(),V9::PHI, 3).addReg(V->second.begin()->second).addReg(kernelValue[V->first]).addRegDef(finalPHIValue[V->first]); 
+     DEBUG(std::cerr << "Resulting PHI: " << *saveValue << "\n");
+     kernelPHIs[V->first][schedule.getMaxStage()-1] = kernelValue[V->first];
+   }
+   else {
+
+     //Keep track of last phi created.
+     Instruction *lastPhi = 0;
+     
+     unsigned count = 1;
+     //Loop over the the map backwards to generate phis
+     for(std::map<int, Value*>::reverse_iterator I = V->second.rbegin(), IE = V->second.rend(); 
+	 I != IE; ++I) {
+
+       if(count < (V->second).size()) {
+	 if(lastPhi == 0) {
+	   lastPhi = new TmpInstruction(I->second);
+	   MachineInstr *saveValue = BuildMI(*machineBB, machineBB->begin(), V9::PHI, 3).addReg(kernelValue[V->first]).addReg(I->second).addRegDef(lastPhi);
+	   DEBUG(std::cerr << "Resulting PHI: " << *saveValue << "\n");
+	   newValLocation[lastPhi] = machineBB;
+	 }
+	 else {
+	   Instruction *tmp = new TmpInstruction(I->second);
+	   MachineInstr *saveValue = BuildMI(*machineBB, machineBB->begin(), V9::PHI, 3).addReg(lastPhi).addReg(I->second).addRegDef(tmp);
+	   DEBUG(std::cerr << "Resulting PHI: " << *saveValue << "\n");
+	   lastPhi = tmp;
+	   kernelPHIs[V->first][I->first] = lastPhi;
+	   newValLocation[lastPhi] = machineBB;
+	 }
+       }
+       //Final phi value
+       else {
+	 //The resulting value must be the Value* we created earlier
+	 assert(lastPhi != 0 && "Last phi is NULL!\n");
+	 MachineInstr *saveValue = BuildMI(*machineBB, machineBB->begin(), V9::PHI, 3).addReg(lastPhi).addReg(I->second).addRegDef(finalPHIValue[V->first]);
+	 DEBUG(std::cerr << "Resulting PHI: " << *saveValue << "\n");
+	 kernelPHIs[V->first][I->first] = finalPHIValue[V->first];
+       }
+
+       ++count;
+     }
+
+   }
+ } 
+
+  DEBUG(std::cerr << "KERNEL after PHIs\n");
+  DEBUG(machineBB->print(std::cerr));
+}
+
+
+void ModuloSchedulingPass::removePHIs(const MachineBasicBlock *origBB, std::vector<MachineBasicBlock *> &prologues, std::vector<MachineBasicBlock *> &epilogues, MachineBasicBlock *kernelBB, std::map<Value*, MachineBasicBlock*> &newValLocation) {
+
+  //Worklist to delete things
+  std::vector<std::pair<MachineBasicBlock*, MachineBasicBlock::iterator> > worklist;
+  
+  const TargetInstrInfo *TMI = target.getInstrInfo();
+
+  //Start with the kernel and for each phi insert a copy for the phi def and for each arg
+  for(MachineBasicBlock::iterator I = kernelBB->begin(), E = kernelBB->end(); I != E; ++I) {
+    //Get op code and check if its a phi
+     if(I->getOpcode() == V9::PHI) {
+       Instruction *tmp = 0;
+       for(unsigned i = 0; i < I->getNumOperands(); ++i) {
+	 //Get Operand
+	 const MachineOperand &mOp = I->getOperand(i);
+	 assert(mOp.getType() == MachineOperand::MO_VirtualRegister && "Should be a Value*\n");
+	 
+	 if(!tmp) {
+	   tmp = new TmpInstruction(mOp.getVRegValue());
+	 }
+
+      	 //Now for all our arguments we read, OR to the new TmpInstruction that we created
+	 if(mOp.isUse()) {
+	   DEBUG(std::cerr << "Use: " << mOp << "\n");
+	   //Place a copy at the end of its BB but before the branches
+	   assert(newValLocation.count(mOp.getVRegValue()) && "We must know where this value is located\n");
+	   //Reverse iterate to find the branches, we can safely assume no instructions have been
+	   //put in the nop positions
+	   for(MachineBasicBlock::iterator inst = --(newValLocation[mOp.getVRegValue()])->end(), endBB = (newValLocation[mOp.getVRegValue()])->begin(); inst != endBB; --inst) {
+	     MachineOpCode opc = inst->getOpcode();
+	     if(TMI->isBranch(opc) || TMI->isNop(opc))
+	       continue;
+	     else {
+	       BuildMI(*(newValLocation[mOp.getVRegValue()]), ++inst, V9::ORr, 3).addReg(mOp.getVRegValue()).addImm(0).addRegDef(tmp);
+	       break;
+	     }
+	       
+	   }
+
+	 }
+	 else {
+	   //Remove the phi and replace it with an OR
+	   DEBUG(std::cerr << "Def: " << mOp << "\n");
+	   BuildMI(*kernelBB, I, V9::ORr, 3).addReg(tmp).addImm(0).addRegDef(mOp.getVRegValue());
+	   worklist.push_back(std::make_pair(kernelBB, I));
+	 }
+
+       }
+     }
+       
+  }
+
+  //Remove phis from epilogue
+  for(std::vector<MachineBasicBlock*>::iterator MB = epilogues.begin(), ME = epilogues.end(); MB != ME; ++MB) {
+    for(MachineBasicBlock::iterator I = (*MB)->begin(), E = (*MB)->end(); I != E; ++I) {
+      //Get op code and check if its a phi
+      if(I->getOpcode() == V9::PHI) {
+	Instruction *tmp = 0;
+	for(unsigned i = 0; i < I->getNumOperands(); ++i) {
+	  //Get Operand
+	  const MachineOperand &mOp = I->getOperand(i);
+	  assert(mOp.getType() == MachineOperand::MO_VirtualRegister && "Should be a Value*\n");
+	  
+	  if(!tmp) {
+	    tmp = new TmpInstruction(mOp.getVRegValue());
+	  }
+	  
+	  //Now for all our arguments we read, OR to the new TmpInstruction that we created
+	  if(mOp.isUse()) {
+	    DEBUG(std::cerr << "Use: " << mOp << "\n");
+	    //Place a copy at the end of its BB but before the branches
+	    assert(newValLocation.count(mOp.getVRegValue()) && "We must know where this value is located\n");
+	    //Reverse iterate to find the branches, we can safely assume no instructions have been
+	    //put in the nop positions
+	    for(MachineBasicBlock::iterator inst = --(newValLocation[mOp.getVRegValue()])->end(), endBB = (newValLocation[mOp.getVRegValue()])->begin(); inst != endBB; --inst) {
+	      MachineOpCode opc = inst->getOpcode();
+	      if(TMI->isBranch(opc) || TMI->isNop(opc))
+		continue;
+	      else {
+		BuildMI(*(newValLocation[mOp.getVRegValue()]), ++inst, V9::ORr, 3).addReg(mOp.getVRegValue()).addImm(0).addRegDef(tmp);
+		break;
+	      }
+	      
+	    }
+	    
+	  }
+	  else {
+	    //Remove the phi and replace it with an OR
+	    DEBUG(std::cerr << "Def: " << mOp << "\n");
+	    BuildMI(**MB, I, V9::ORr, 3).addReg(tmp).addImm(0).addRegDef(mOp.getVRegValue());
+	    worklist.push_back(std::make_pair(*MB,I));
+	  }
+	  
+	}
+      }
+    }
+  }
+
+    //Delete the phis
+  for(std::vector<std::pair<MachineBasicBlock*, MachineBasicBlock::iterator> >::iterator I =  worklist.begin(), E = worklist.end(); I != E; ++I) {
+    DEBUG(std::cerr << "Deleting PHI " << I->second << "\n");
+    I->first->erase(I->second);
+		    
+  }
+
+}
+
+
+void ModuloSchedulingPass::reconstructLoop(MachineBasicBlock *BB) {
+
+  DEBUG(std::cerr << "Reconstructing Loop\n");
+
+  //First find the value *'s that we need to "save"
+  std::map<const Value*, std::pair<const MSchedGraphNode*, int> > valuesToSave;
+
+  //Keep track of instructions we have already seen and their stage because
+  //we don't want to "save" values if they are used in the kernel immediately
+  std::map<const MachineInstr*, int> lastInstrs;
+
+  //Loop over kernel and only look at instructions from a stage > 0
+  //Look at its operands and save values *'s that are read
+  for(MSSchedule::kernel_iterator I = schedule.kernel_begin(), E = schedule.kernel_end(); I != E; ++I) {
+
+    if(I->second !=0) {
+      //For this instruction, get the Value*'s that it reads and put them into the set.
+      //Assert if there is an operand of another type that we need to save
+      const MachineInstr *inst = I->first->getInst();
+      lastInstrs[inst] = I->second;
+
+      for(unsigned i=0; i < inst->getNumOperands(); ++i) {
+	//get machine operand
+	const MachineOperand &mOp = inst->getOperand(i);
+	
+	if(mOp.getType() == MachineOperand::MO_VirtualRegister && mOp.isUse()) {
+	  //find the value in the map
+	  if (const Value* srcI = mOp.getVRegValue()) {
+
+	    //Before we declare this Value* one that we should save
+	    //make sure its def is not of the same stage as this instruction
+	    //because it will be consumed before its used
+	    Instruction *defInst = (Instruction*) srcI;
+	    
+	    //Should we save this value?
+	    bool save = true;
+
+	    //Get Machine code for this instruction, and loop backwards over the array
+	    //to find the def
+	    MachineCodeForInstruction & tempMvec = MachineCodeForInstruction::get(defInst);
+	    for (int j = tempMvec.size()-1; j >= 0; j--) {
+	       MachineInstr *temp = tempMvec[j];
+	       
+	       //Loop over instructions
+	       for(unsigned opNum = 0; opNum < temp->getNumOperands(); ++opNum) {
+		 MachineOperand &mDefOp = temp->getOperand(opNum);
+		 
+		 if (mDefOp.getType() == MachineOperand::MO_VirtualRegister && mDefOp.isDef()) {
+		   const Value* defVReg = mDefOp.getVRegValue();
+		   if(defVReg == srcI) {
+		     //Check if instruction has been seen already and is of same stage
+		     if(lastInstrs.count(temp)) {
+		       if(lastInstrs[temp] == I->second)
+			 save = false;
+		     }
+		   }
+		 }
+	       }
+	    }
+	    if(save)
+	      valuesToSave[srcI] = std::make_pair(I->first, i);
+	  }	  
+	}
+	
+	if(mOp.getType() != MachineOperand::MO_VirtualRegister && mOp.isUse()) {
+	  assert("Our assumption is wrong. We have another type of register that needs to be saved\n");
+	}
+      }
+    }
+  }
+
+  //The new loop will consist of one or more prologues, the kernel, and one or more epilogues.
+
+  //Map to keep track of old to new values
+  std::map<Value*, std::map<int, Value*> > newValues;
+ 
+  //Map to keep track of old to new values in kernel
+  std::map<Value*, std::map<int, Value*> > kernelPHIs;
+
+  //Another map to keep track of what machine basic blocks these new value*s are in since
+  //they have no llvm instruction equivalent
+  std::map<Value*, MachineBasicBlock*> newValLocation;
+
+  std::vector<MachineBasicBlock*> prologues;
+  std::vector<BasicBlock*> llvm_prologues;
+
+
+  //Write prologue
+  writePrologues(prologues, BB, llvm_prologues, valuesToSave, newValues, newValLocation);
+    
+  //Print out epilogues and prologue
+  DEBUG(for(std::vector<MachineBasicBlock*>::iterator I = prologues.begin(), E = prologues.end(); 
+      I != E; ++I) {
+    std::cerr << "PROLOGUE\n";
+    (*I)->print(std::cerr);
+  });
+
+  BasicBlock *llvmKernelBB = new BasicBlock("Kernel", (Function*) (BB->getBasicBlock()->getParent()));
+  MachineBasicBlock *machineKernelBB = new MachineBasicBlock(llvmKernelBB);
+  (((MachineBasicBlock*)BB)->getParent())->getBasicBlockList().push_back(machineKernelBB);
+  writeKernel(llvmKernelBB, machineKernelBB, valuesToSave, newValues, newValLocation, kernelPHIs);
+  
+ 
+  std::vector<MachineBasicBlock*> epilogues;
+  std::vector<BasicBlock*> llvm_epilogues;
+
+  //Write epilogues
+  writeEpilogues(epilogues, BB, llvm_epilogues, valuesToSave, newValues, newValLocation, kernelPHIs);
+
+
+  const TargetInstrInfo *TMI = target.getInstrInfo();
+
+  //Fix up machineBB and llvmBB branches
+  for(unsigned I = 0; I <  prologues.size(); ++I) {
+   
+    MachineInstr *branch = 0;
+    
+    //Find terminator since getFirstTerminator does not work!
+    for(MachineBasicBlock::reverse_iterator mInst = prologues[I]->rbegin(), mInstEnd = prologues[I]->rend(); mInst != mInstEnd; ++mInst) {
+      MachineOpCode OC = mInst->getOpcode();
+      if(TMI->isBranch(OC)) {
+	branch = &*mInst;
+	DEBUG(std::cerr << *mInst << "\n");
+	break;
+      }
+    }
+
+   
+ 
+    //Update branch
+    for(unsigned opNum = 0; opNum < branch->getNumOperands(); ++opNum) {
+      MachineOperand &mOp = branch->getOperand(opNum);
+      if (mOp.getType() == MachineOperand::MO_PCRelativeDisp) {
+	mOp.setValueReg(llvm_epilogues[(llvm_epilogues.size()-1-I)]);
+      }
+    }
+
+    //Update llvm basic block with our new branch instr
+    DEBUG(std::cerr << BB->getBasicBlock()->getTerminator() << "\n");
+    const BranchInst *branchVal = dyn_cast<BranchInst>(BB->getBasicBlock()->getTerminator());
+    TmpInstruction *tmp = new TmpInstruction(branchVal->getCondition());
+    if(I == prologues.size()-1) {
+      TerminatorInst *newBranch = new BranchInst(llvmKernelBB,
+						 llvm_epilogues[(llvm_epilogues.size()-1-I)], 
+						 tmp, 
+						 llvm_prologues[I]);
+    }
+    else
+      TerminatorInst *newBranch = new BranchInst(llvm_prologues[I+1],
+						 llvm_epilogues[(llvm_epilogues.size()-1-I)], 
+						 tmp, 
+						 llvm_prologues[I]);
+
+    assert(branch != 0 && "There must be a terminator for this machine basic block!\n");
+  
+    //Push nop onto end of machine basic block
+    BuildMI(prologues[I], V9::NOP, 0);
+    
+    //Add a unconditional branch to the next prologue
+    if(I != prologues.size()-1)
+      BuildMI(prologues[I], V9::BA, 1).addPCDisp(llvm_prologues[I+1]);
+    else
+      BuildMI(prologues[I], V9::BA, 1).addPCDisp(llvmKernelBB);
+
+    //Add one more nop!
+    BuildMI(prologues[I], V9::NOP, 0);
+  }
+
+  //Fix up kernel machine branches
+  MachineInstr *branch = 0;
+  for(MachineBasicBlock::reverse_iterator mInst = machineKernelBB->rbegin(), mInstEnd = machineKernelBB->rend(); mInst != mInstEnd; ++mInst) {
+    MachineOpCode OC = mInst->getOpcode();
+    if(TMI->isBranch(OC)) {
+      branch = &*mInst;
+      DEBUG(std::cerr << *mInst << "\n");
+      break;
+    }
+  }
+
+  assert(branch != 0 && "There must be a terminator for the kernel machine basic block!\n");
+   
+  //Update kernel self loop branch
+  for(unsigned opNum = 0; opNum < branch->getNumOperands(); ++opNum) {
+    MachineOperand &mOp = branch->getOperand(opNum);
+    
+    if (mOp.getType() == MachineOperand::MO_PCRelativeDisp) {
+      mOp.setValueReg(llvmKernelBB);
+    }
+  }
+  
+  //Update kernelLLVM branches
+  const BranchInst *branchVal = dyn_cast<BranchInst>(BB->getBasicBlock()->getTerminator());
+  TerminatorInst *newBranch = new BranchInst(llvmKernelBB,
+					     llvm_epilogues[0], 
+					     new TmpInstruction(branchVal->getCondition()), 
+					     llvmKernelBB);
+
+  //Add kernel noop
+   BuildMI(machineKernelBB, V9::NOP, 0);
+
+   //Add unconditional branch to first epilogue
+   BuildMI(machineKernelBB, V9::BA, 1).addPCDisp(llvm_epilogues[0]);
+
+
+   //Add kernel noop
+   BuildMI(machineKernelBB, V9::NOP, 0);
+
+   //Lastly add unconditional branches for the epilogues
+   for(unsigned I = 0; I <  epilogues.size(); ++I) {
+     
+    //Now since I don't trust fall throughs, add a unconditional branch to the next prologue
+     if(I != epilogues.size()-1) {
+       BuildMI(epilogues[I], V9::BA, 1).addPCDisp(llvm_epilogues[I+1]);
+       //Add unconditional branch to end of epilogue
+       TerminatorInst *newBranch = new BranchInst(llvm_epilogues[I+1], 
+						  llvm_epilogues[I]);
+
+     }
+    else {
+      MachineBasicBlock *origBlock = (MachineBasicBlock*) BB;
+      for(MachineBasicBlock::reverse_iterator inst = origBlock->rbegin(), instEnd = origBlock->rend(); inst != instEnd; ++inst) {
+	MachineOpCode OC = inst->getOpcode();
+	if(TMI->isBranch(OC)) {
+	  branch = &*inst;
+	  DEBUG(std::cerr << "Exit branch from loop" << *inst << "\n");
+	  break;
+	
+	}
+	
+	for(unsigned opNum = 0; opNum < branch->getNumOperands(); ++opNum) {
+	  MachineOperand &mOp = branch->getOperand(opNum);
+	  
+	  if (mOp.getType() == MachineOperand::MO_PCRelativeDisp) {
+	    BuildMI(epilogues[I], V9::BA, 1).addPCDisp(mOp.getVRegValue());
+	    break;
+	  }
+	}
+	
+      }
+      
+      //Update last epilogue exit branch
+      BranchInst *branchVal = (BranchInst*) dyn_cast<BranchInst>(BB->getBasicBlock()->getTerminator());
+      //Find where we are supposed to branch to
+      BasicBlock *nextBlock = 0;
+      for(unsigned j=0; j <branchVal->getNumSuccessors(); ++j) {
+	if(branchVal->getSuccessor(j) != BB->getBasicBlock())
+	  nextBlock = branchVal->getSuccessor(j);
+      }
+	TerminatorInst *newBranch = new BranchInst(nextBlock, llvm_epilogues[I]);
+    }
+    //Add one more nop!
+    BuildMI(epilogues[I], V9::NOP, 0);
+
+   }
+
+   //FIX UP Machine BB entry!!
+   //We are looking at the predecesor of our loop basic block and we want to change its ba instruction
+   
+
+   //Find all llvm basic blocks that branch to the loop entry and change to our first prologue.
+   const BasicBlock *llvmBB = BB->getBasicBlock();
+
+   for(pred_const_iterator P = pred_begin(llvmBB), PE = pred_end(llvmBB); P != PE; ++PE) {
+     if(*P == llvmBB)
+       continue;
+     else {
+       DEBUG(std::cerr << "Found our entry BB\n");
+       //Get the Terminator instruction for this basic block and print it out
+       DEBUG(std::cerr << *((*P)->getTerminator()) << "\n");
+       //Update the terminator
+       TerminatorInst *term = ((BasicBlock*)*P)->getTerminator();
+       for(unsigned i=0; i < term->getNumSuccessors(); ++i) {
+	 if(term->getSuccessor(i) == llvmBB) {
+	   DEBUG(std::cerr << "Replacing successor bb\n");
+	   if(llvm_prologues.size() > 0) {
+	     term->setSuccessor(i, llvm_prologues[0]);
+	     //Also update its corresponding machine instruction
+	     MachineCodeForInstruction & tempMvec =
+	       MachineCodeForInstruction::get(term);
+	     for (unsigned j = 0; j < tempMvec.size(); j++) {
+	       MachineInstr *temp = tempMvec[j];
+	       MachineOpCode opc = temp->getOpcode();
+	       if(TMI->isBranch(opc)) {
+		 DEBUG(std::cerr << *temp << "\n");
+		 //Update branch
+		 for(unsigned opNum = 0; opNum < temp->getNumOperands(); ++opNum) {
+		   MachineOperand &mOp = temp->getOperand(opNum);
+		   if (mOp.getType() == MachineOperand::MO_PCRelativeDisp) {
+		     mOp.setValueReg(llvm_prologues[0]);
+		   }
+		 }
+	       }
+	     }        
+	   }
+	   else {
+	     term->setSuccessor(i, llvmKernelBB);
+	   //Also update its corresponding machine instruction
+	     MachineCodeForInstruction & tempMvec =
+	       MachineCodeForInstruction::get(term);
+	     for (unsigned j = 0; j < tempMvec.size(); j++) {
+	       MachineInstr *temp = tempMvec[j];
+	       MachineOpCode opc = temp->getOpcode();
+	       if(TMI->isBranch(opc)) {
+		 DEBUG(std::cerr << *temp << "\n");
+		 //Update branch
+		 for(unsigned opNum = 0; opNum < temp->getNumOperands(); ++opNum) {
+		   MachineOperand &mOp = temp->getOperand(opNum);
+		   if (mOp.getType() == MachineOperand::MO_PCRelativeDisp) {
+		     mOp.setValueReg(llvmKernelBB);
+		   }
+		 }
+	       }
+	     }
+	   }
+	 }
+       }
+       break;
+     }
+   }
+   
+   removePHIs(BB, prologues, epilogues, machineKernelBB, newValLocation);
+
+
+    
+  //Print out epilogues and prologue
+  DEBUG(for(std::vector<MachineBasicBlock*>::iterator I = prologues.begin(), E = prologues.end(); 
+      I != E; ++I) {
+    std::cerr << "PROLOGUE\n";
+    (*I)->print(std::cerr);
+  });
+  
+  DEBUG(std::cerr << "KERNEL\n");
+  DEBUG(machineKernelBB->print(std::cerr));
+
+  DEBUG(for(std::vector<MachineBasicBlock*>::iterator I = epilogues.begin(), E = epilogues.end(); 
+      I != E; ++I) {
+    std::cerr << "EPILOGUE\n";
+    (*I)->print(std::cerr);
+  });
+
+
+  DEBUG(std::cerr << "New Machine Function" << "\n");
+  DEBUG(std::cerr << BB->getParent() << "\n");
+
+  //BB->getParent()->getBasicBlockList().erase(BB);
+
+}
+