Updating my versions of ModuloScheduling in cvs. Still not complete.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13424 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 860 insertions, 303 deletions

diff --git a/lib/CodeGen/ModuloScheduling/MSchedGraph.cpp b/lib/CodeGen/ModuloScheduling/MSchedGraph.cpp
index b76a97fe64..6db099488e 100644
--- a/lib/CodeGen/ModuloScheduling/MSchedGraph.cpp
+++ b/lib/CodeGen/ModuloScheduling/MSchedGraph.cpp
@@ -29,7 +29,7 @@ MSchedGraphNode::MSchedGraphNode(const MachineInstr* inst,
 }
 
 void MSchedGraphNode::print(std::ostream &os) const {
-  os << "MSehedGraphNode: Inst=" << *Inst << ", latency= " << latency << "\n"; 
+  os << "MSchedGraphNode: Inst=" << *Inst << ", latency= " << latency << "\n"; 
 }
 
 MSchedGraphEdge MSchedGraphNode::getInEdge(MSchedGraphNode *pred) {
@@ -41,9 +41,38 @@ MSchedGraphEdge MSchedGraphNode::getInEdge(MSchedGraphNode *pred) {
       return I.getEdge();
   }
   assert(0 && "Should have found edge between this node and its predecessor!");
-  
+ 
 }
 
+unsigned MSchedGraphNode::getInEdgeNum(MSchedGraphNode *pred) {
+  //Loop over all the successors of our predecessor
+  //return the edge the corresponds to this in edge
+  int count = 0;
+  for(MSchedGraphNode::succ_iterator I = pred->succ_begin(), E = pred->succ_end();
+      I != E; ++I) {
+    if(*I == this)
+      return count;
+    count++;
+  }
+  assert(0 && "Should have found edge between this node and its predecessor!");
+  abort();
+}
+bool MSchedGraphNode::isSuccessor(MSchedGraphNode *succ) {
+  for(succ_iterator I = succ_begin(), E = succ_end(); I != E; ++I)
+    if(*I == succ)
+      return true;
+  return false;
+}
+
+
+bool MSchedGraphNode::isPredecessor(MSchedGraphNode *pred) {
+  if(find( Predecessors.begin(),  Predecessors.end(), pred) !=   Predecessors.end())
+    return true;
+  else
+    return false;
+}
+
+
 void MSchedGraph::addNode(const MachineInstr *MI,
 			  MSchedGraphNode *node) {
   
@@ -92,12 +121,15 @@ void MSchedGraph::buildNodesAndEdges() {
     MachineOpCode MIopCode = MI->getOpcode();
     int delay;
 
+#if 0  // FIXME: LOOK INTO THIS
     //Check if subsequent instructions can be issued before
     //the result is ready, if so use min delay.
     if(MTI.hasResultInterlock(MIopCode))
       delay = MTI.minLatency(MIopCode);
     else
-      delay = MTI.maxLatency(MIopCode);
+#endif
+      /// FIxME: get this from the sched class.
+      delay = 7; //MTI.maxLatency(MIopCode);
     
     //Create new node for this machine instruction and add to the graph.
     //Create only if not a nop
diff --git a/lib/CodeGen/ModuloScheduling/MSchedGraph.h b/lib/CodeGen/ModuloScheduling/MSchedGraph.h
index 9fe6b52c47..9680fc0994 100644
--- a/lib/CodeGen/ModuloScheduling/MSchedGraph.h
+++ b/lib/CodeGen/ModuloScheduling/MSchedGraph.h
@@ -99,6 +99,10 @@ namespace llvm {
     bool hasSuccessors() { return (Successors.size() > 0); }
     int getLatency() { return latency; }
     MSchedGraphEdge getInEdge(MSchedGraphNode *pred);
+    unsigned getInEdgeNum(MSchedGraphNode *pred);
+
+    bool isSuccessor(MSchedGraphNode *);
+    bool isPredecessor(MSchedGraphNode *);
 
     //Debug support
     void print(std::ostream &os) const;
diff --git a/lib/CodeGen/ModuloScheduling/ModuloScheduling.cpp b/lib/CodeGen/ModuloScheduling/ModuloScheduling.cpp
index acc0276c92..508467eb97 100644
--- a/lib/CodeGen/ModuloScheduling/ModuloScheduling.cpp
+++ b/lib/CodeGen/ModuloScheduling/ModuloScheduling.cpp
@@ -20,12 +20,14 @@
 #include "llvm/Target/TargetSchedInfo.h"
 #include "Support/Debug.h"
 #include "Support/GraphWriter.h"
+#include "Support/StringExtras.h"
 #include <vector>
 #include <utility>
 #include <iostream>
 #include <fstream>
 #include <sstream>
 
+
 using namespace llvm;
 
 /// Create ModuloSchedulingPass
@@ -88,14 +90,20 @@ namespace llvm {
 	edgelabel = "Unknown";
 	break;
       }
-      if(I.getEdge().getIteDiff() > 0)
-	edgelabel += I.getEdge().getIteDiff();
-      
-      return edgelabel;
-  }
 
+      //FIXME
+      int iteDiff = I.getEdge().getIteDiff();
+      std::string intStr = "(IteDiff: ";
+      intStr += itostr(iteDiff);
 
+      intStr += ")";
+      edgelabel += intStr;
 
+      return edgelabel;
+    }
+    
+    
+    
   };
 }
 
@@ -114,7 +122,7 @@ bool ModuloSchedulingPass::runOnFunction(Function &F) {
       MSchedGraph *MSG = new MSchedGraph(BI, target);
     
       //Write Graph out to file
-      DEBUG(WriteGraphToFile(std::cerr, "dependgraph", MSG));
+      DEBUG(WriteGraphToFile(std::cerr, F.getName(), MSG));
 
       //Print out BB for debugging
       DEBUG(BI->print(std::cerr));
@@ -122,9 +130,64 @@ bool ModuloSchedulingPass::runOnFunction(Function &F) {
       //Calculate Resource II
       int ResMII = calculateResMII(BI);
   
+      //Calculate Recurrence II
+      int RecMII = calculateRecMII(MSG, ResMII);
+
+      II = std::max(RecMII, ResMII);
+
+      DEBUG(std::cerr << "II starts out as " << II << "\n");
+
+      //Calculate Node Properties
       calculateNodeAttributes(MSG, ResMII);
+
+      //Dump node properties if in debug mode
+      for(std::map<MSchedGraphNode*, MSNodeAttributes>::iterator I =  nodeToAttributesMap.begin(), E = nodeToAttributesMap.end(); I !=E; ++I) {
+	DEBUG(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
+      for(std::vector<std::vector<MSchedGraphNode*> >::iterator I = partialOrder.begin(), E = partialOrder.end(); I !=E; ++I) {
+	DEBUG(std::cerr << "Start set in PO\n");
+	for(std::vector<MSchedGraphNode*>::iterator J = I->begin(), JE = I->end(); J != JE; ++J)
+	  DEBUG(std::cerr << "PO:" << **J << "\n");
+      }
+
+      orderNodes();
+
+      //Dump out order of nodes
+      for(std::vector<MSchedGraphNode*>::iterator I = FinalNodeOrder.begin(), E = FinalNodeOrder.end(); I != E; ++I)
+	DEBUG(std::cerr << "FO:" << **I << "\n");
+
+
+      //Finally schedule nodes
+      computeSchedule();
+
+
+      //Dump out final schedule
+      //std::cerr << "FINALSCHEDULE\n";
+  //Dump out current schedule
+  /*for(std::map<unsigned, std::vector<std::pair<unsigned, MSchedGraphNode*> > >::iterator J = schedule.begin(), 
+	JE = schedule.end(); J != JE; ++J) {
+    std::cerr << "Cycle " << J->first << ":\n";
+    for(std::vector<std::pair<unsigned, MSchedGraphNode*> >::iterator VI = J->second.begin(), VE = J->second.end(); VI != VE; ++VI)
+      std::cerr << "Resource ID: " << VI->first << " by node " << *(VI->second) << "\n";
+  }
+  std::cerr << "END FINAL SCHEDULE\n";
+
+      DEBUG(std::cerr << "II ends up as " << II << "\n");
+  */  
+
+
+      nodeToAttributesMap.clear();
+      partialOrder.clear();
+      recurrenceList.clear();
+      FinalNodeOrder.clear();
+      schedule.clear();
+      }
     
-    }
   }
 
 
@@ -201,8 +264,8 @@ int ModuloSchedulingPass::calculateResMII(const MachineBasicBlock *BI) {
 
   //Find maximum usage count
   
-  //Get max number of instructions that can be issued at once.
-  int issueSlots = msi.maxNumIssueTotal;
+  //Get max number of instructions that can be issued at once. (FIXME)
+  int issueSlots = 1; // 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
@@ -228,10 +291,34 @@ int ModuloSchedulingPass::calculateResMII(const MachineBasicBlock *BI) {
   }
 
   DEBUG(std::cerr << "Final Resource MII: " << ResMII << "\n");
+  
   return ResMII;
 
 }
 
+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) {
+    std::cerr << "Recurrence: \n";
+    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);
+    std::cerr << "End Recurrence with RecMII: " << I->first << "\n";
+    }
+  DEBUG(std::cerr << "RecMII: " << RecMII << "\n");
+  
+  return MII;
+}
+
 void ModuloSchedulingPass::calculateNodeAttributes(MSchedGraph *graph, int MII) {
 
   //Loop over the nodes and add them to the map
@@ -245,114 +332,135 @@ void ModuloSchedulingPass::calculateNodeAttributes(MSchedGraph *graph, int MII)
 
   //Create set to deal with reccurrences
   std::set<MSchedGraphNode*> visitedNodes;
-  std::vector<MSchedGraphNode*> vNodes;
+  
   //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, (I->second), MII, visitedNodes);
-    findAllReccurrences(I->first, vNodes);
-    vNodes.clear();
+    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, (I->second), MII, MII, visitedNodes);
+  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 = (I->second).ALAP - (I->second).ASAP;
+  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, (I->second), visitedNodes);
-    visitedNodes.clear();
-    calculateHeight(I->first, (I->second), visitedNodes);
-    visitedNodes.clear();
-  }*/
+    calculateDepth(I->first, (MSchedGraphNode*) 0);
+    calculateHeight(I->first, (MSchedGraphNode*) 0);
+  }
+
+
+}
 
+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)));
+  DEBUG(std::cerr << "Ignore Edge from " << *srcNode << " to " << *destNode << "? " << findEdge << "\n");
+  return findEdge;
 }
 
-void ModuloSchedulingPass::calculateASAP(MSchedGraphNode *node, MSNodeAttributes &attributes, 
-					 int MII, std::set<MSchedGraphNode*> &visitedNodes) {
+int  ModuloSchedulingPass::calculateASAP(MSchedGraphNode *node, int MII, MSchedGraphNode *destNode) {
     
   DEBUG(std::cerr << "Calculating ASAP for " << *node << "\n");
 
-  if(attributes.ASAP != -1 || (visitedNodes.find(node) != visitedNodes.end())) {
-    visitedNodes.erase(node);
-    return;
-  }
-  if(node->hasPredecessors()) {
-    int maxPredValue = 0;
+  //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) {
     
-    //Iterate over all of the predecessors and fine max
-    for(MSchedGraphNode::pred_iterator P = node->pred_begin(), E = node->pred_end(); P != E; ++P) {
-
-      //Get that nodes ASAP
-      MSNodeAttributes predAttributes = nodeToAttributesMap.find(*P)->second;
-      if(predAttributes.ASAP == -1) {
-	//Put into set before you recurse
-	visitedNodes.insert(node);
-	calculateASAP(*P, predAttributes, MII, visitedNodes);
-	predAttributes = nodeToAttributesMap.find(*P)->second;
-      }
+    //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 = predAttributes.ASAP + node->getLatency() - iteDiff * MII;
-      DEBUG(std::cerr << "Current ASAP pred: " << currentPredValue << "\n");
+      
+      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);
     }
-    visitedNodes.erase(node);
-    attributes.ASAP = maxPredValue;
-  }
-  else {
-    visitedNodes.erase(node);
-    attributes.ASAP = 0;
   }
+  
+  attributes.ASAP = maxPredValue;
 
   DEBUG(std::cerr << "ASAP: " << attributes.ASAP << " (" << *node << ")\n");
+  
+  return maxPredValue;
 }
 
 
-void ModuloSchedulingPass::calculateALAP(MSchedGraphNode *node, MSNodeAttributes &attributes, 
-					 int MII, int maxASAP, 
-					 std::set<MSchedGraphNode*> &visitedNodes) {
+int ModuloSchedulingPass::calculateALAP(MSchedGraphNode *node, int MII, 
+					int maxASAP, MSchedGraphNode *srcNode) {
   
-  DEBUG(std::cerr << "Calculating AlAP for " << *node << "\n");
+  DEBUG(std::cerr << "Calculating ALAP for " << *node << "\n");
   
-  if(attributes.ALAP != -1|| (visitedNodes.find(node) != visitedNodes.end())) {
-   visitedNodes.erase(node);
-   return;
-  }
+  MSNodeAttributes &attributes = nodeToAttributesMap.find(node)->second;
+ 
+  if(attributes.ALAP != -1)
+    return attributes.ALAP;
+ 
   if(node->hasSuccessors()) {
-    int minSuccValue = 0;
+    
+    //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) {
-
-      MSNodeAttributes succAttributes = nodeToAttributesMap.find(*P)->second;
-      if(succAttributes.ASAP == -1) {
+      
+      //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");
 	
-	//Put into set before recursing
-	visitedNodes.insert(node);
+	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");
 
-	calculateALAP(*P, succAttributes, MII, maxASAP, visitedNodes);
-	succAttributes = nodeToAttributesMap.find(*P)->second;
-	assert(succAttributes.ASAP == -1 && "Successors ALAP should have been caclulated");
+	minSuccValue = std::min(minSuccValue, currentSuccValue);
       }
-      int iteDiff = P.getEdge().getIteDiff();
-      int currentSuccValue = succAttributes.ALAP + node->getLatency() + iteDiff * MII;
-      minSuccValue = std::min(minSuccValue, currentSuccValue);
     }
-    visitedNodes.erase(node);
-    attributes.ALAP = minSuccValue;
+    
+    if(processedOneEdge)
+    	attributes.ALAP = minSuccValue;
+    
+    else
+      attributes.ALAP = maxASAP;
   }
-  else {
-    visitedNodes.erase(node);
+  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() {
@@ -365,253 +473,417 @@ int ModuloSchedulingPass::findMaxASAP() {
 }
 
 
-void ModuloSchedulingPass::calculateHeight(MSchedGraphNode *node, 
-					   MSNodeAttributes &attributes,
-					   std::set<MSchedGraphNode*> &visitedNodes) {
+int ModuloSchedulingPass::calculateHeight(MSchedGraphNode *node,MSchedGraphNode *srcNode) {
+  
+  MSNodeAttributes &attributes = nodeToAttributesMap.find(node)->second;
 
-  if(attributes.depth != -1 || (visitedNodes.find(node) != visitedNodes.end())) {
-    //Remove from map before returning
-    visitedNodes.erase(node);
-    return;
-  }
+  if(attributes.height != -1)
+    return attributes.height;
 
-  if(node->hasSuccessors()) {
-    int maxHeight = 0;
+  int maxHeight = 0;
     
-    //Iterate over all of the predecessors and fine max
-    for(MSchedGraphNode::succ_iterator P = node->succ_begin(), 
-	  E = node->succ_end(); P != E; ++P) {
+  //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);
 
-      MSNodeAttributes succAttributes = nodeToAttributesMap.find(*P)->second;
-      if(succAttributes.height == -1) {
-	
-	//Put into map before recursing
-	visitedNodes.insert(node);
+      assert(succHeight != -1 && "Successors Height should have been caclulated");
 
-	calculateHeight(*P, succAttributes, visitedNodes);
-	succAttributes = nodeToAttributesMap.find(*P)->second;
-	assert(succAttributes.height == -1 && "Successors Height should have been caclulated");
-      }
-      int currentHeight = succAttributes.height + node->getLatency();
+      int currentHeight = succHeight + node->getLatency();
       maxHeight = std::max(maxHeight, currentHeight);
     }
-    visitedNodes.erase(node);
-    attributes.height = maxHeight;
   }
-  else {
-    visitedNodes.erase(node);
-    attributes.height = 0;
-  }
-
-    DEBUG(std::cerr << "Height: " << attributes.height << " (" << *node << ")\n");
+  attributes.height = maxHeight;
+  DEBUG(std::cerr << "Height: " << attributes.height << " (" << *node << ")\n");
+  return maxHeight;
 }
 
 
-void ModuloSchedulingPass::calculateDepth(MSchedGraphNode *node, 
-					  MSNodeAttributes &attributes, 
-					  std::set<MSchedGraphNode*> &visitedNodes) {
-  
-  if(attributes.depth != -1 || (visitedNodes.find(node) != visitedNodes.end())) {
-    //Remove from map before returning
-    visitedNodes.erase(node);
-    return;
-  }
+int ModuloSchedulingPass::calculateDepth(MSchedGraphNode *node, 
+					  MSchedGraphNode *destNode) {
 
-  if(node->hasPredecessors()) {
-    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) {
+  MSNodeAttributes &attributes = nodeToAttributesMap.find(node)->second;
 
-      //Get that nodes depth
-      MSNodeAttributes predAttributes = nodeToAttributesMap.find(*P)->second;
-      if(predAttributes.depth == -1) {
-	
-	//Put into set before recursing
-	visitedNodes.insert(node);
-	
-	calculateDepth(*P, predAttributes, visitedNodes);
-	predAttributes = nodeToAttributesMap.find(*P)->second;
-	assert(predAttributes.depth == -1 && "Predecessors ASAP should have been caclulated");
-      }
-      int currentDepth = predAttributes.depth + node->getLatency();
+  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);
     }
-
-    //Remove from map before returning
-    visitedNodes.erase(node);
-   
-    attributes.height = maxDepth;
-  }
-  else {
-    //Remove from map before returning
-    visitedNodes.erase(node);
-    attributes.depth = 0;
   }
-
+  attributes.depth = maxDepth;
+  
   DEBUG(std::cerr << "Depth: " << attributes.depth << " (" << *node << "*)\n");
-
+  return maxDepth;
 }
 
 
-void ModuloSchedulingPass::findAllReccurrences(MSchedGraphNode *node, 
-					       std::vector<MSchedGraphNode*> &visitedNodes) {
+
+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(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) {
+    //if(srcBENode == 0 || destBENode == 0) {
+      srcBENode = recurrence.back();
+      destBENode = recurrence.front();
+      //}
+    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(find(visitedNodes.begin(), visitedNodes.end(), node) != visitedNodes.end()) {
-    //DUMP out recurrence
-    DEBUG(std::cerr << "Reccurrence:\n");
+    std::vector<MSchedGraphNode*> recurrence;
     bool first = true;
+    int delay = 0;
+    int distance = 0;
+    int RecMII = II; //Starting value
+    MSchedGraphNode *last = node;
+    MSchedGraphNode *srcBackEdge;
+    MSchedGraphNode *destBackEdge;
+    
+
+
     for(std::vector<MSchedGraphNode*>::iterator I = visitedNodes.begin(), E = visitedNodes.end();
 	I !=E; ++I) {
-      if(*I == node)
+
+      if(*I == node) 
 	first = false;
       if(first)
 	continue;
-      DEBUG(std::cerr << **I << "\n");
+
+      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;
     }
-     DEBUG(std::cerr << "End Reccurrence:\n");
+
+
+      
+    //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);
+    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(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(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(find(PO->begin(), PO->end(), *P) != PO->end())
+		    predFound = true;
+		}
+		
+		if(!predFound)
+		  if(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(find(PO->begin(), PO->end(), I->first) != PO->end())
+	found = true;
+    }
+    if(!found)
+      lastNodes.push_back(I->first);
+  }
 
-void ModuloSchedulingPass::orderNodes() {
+  if(lastNodes.size() > 0)
+    partialOrder.push_back(lastNodes);
   
-  int BOTTOM_UP = 0;
-  int TOP_DOWN = 1;
+}
+
 
-  //FIXME: Group nodes into sets and order all the sets based on RecMII
-  typedef std::vector<MSchedGraphNode*> NodeVector;
-  typedef std::pair<int, NodeVector> NodeSet; 
+void ModuloSchedulingPass::predIntersect(std::vector<MSchedGraphNode*> &CurrentSet, std::vector<MSchedGraphNode*> &IntersectResult) {
   
-  std::vector<NodeSet> NodeSetsToOrder;
+  //Sort CurrentSet so we can use lowerbound
+  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(find(CurrentSet.begin(), 
+		     CurrentSet.end(), *P) != CurrentSet.end())
+	if(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
+  sort(CurrentSet.begin(), CurrentSet.end());
   
-  //Order the resulting sets
-  NodeVector FinalNodeOrder;
+  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) {
 
-  //Loop over all the sets and place them in the final node order
-  for(unsigned i=0; i < NodeSetsToOrder.size(); ++i) {
+      //Check if we are supposed to ignore this edge or not
+      if(ignoreEdge(FinalNodeOrder[j],*P))
+	continue;
+
+      if(find(CurrentSet.begin(), 
+		     CurrentSet.end(), *P) != CurrentSet.end())
+	if(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";
+}
 
-    //Set default order
-    int order = BOTTOM_UP;
 
-    //Get Nodes in Current set
-    NodeVector CurrentSet = NodeSetsToOrder[i].second;
 
-    //Loop through the predecessors for each node in the final order
-    //and only keeps nodes both in the pred_set and currentset
-    NodeVector IntersectCurrent;
+void ModuloSchedulingPass::orderNodes() {
+  
+  int BOTTOM_UP = 0;
+  int TOP_DOWN = 1;
+
+  //Set default order
+  int order = BOTTOM_UP;
 
-    //Sort CurrentSet so we can use lowerbound
-    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) {
-	if(lower_bound(CurrentSet.begin(), 
-		       CurrentSet.end(), *P) != CurrentSet.end())
-	  IntersectCurrent.push_back(*P);
-      }
-    }
+  //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");
+    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)
+    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");
 
-      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) {
-	  if(lower_bound(CurrentSet.begin(), 
-			 CurrentSet.end(), *P) != CurrentSet.end())
-	    IntersectCurrent.push_back(*P);
-	}
-      }
+      succIntersect(*CurrentSet, IntersectCurrent);
 
       //sort top-down
-      if(IntersectCurrent.size() != 0)
+      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;
-	for(unsigned j=0; j < CurrentSet.size(); ++j) {
+	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;
+	  MSNodeAttributes nodeAttr= nodeToAttributesMap.find((*CurrentSet)[j])->second;
 	  //assert(nodeAttr != nodeToAttributesMap.end() && "Node not in attributes map!");
-      
+	  DEBUG(std::cerr <&