lib/Analysis/DataStructure/BottomUpClosure.cpp - fp2-dev/platform/external/llvm - Gitiles

 //===- BottomUpClosure.cpp - Compute bottom-up interprocedural closure ----===//
 //
 // This file implements the BUDataStructures class, which represents the
 // Bottom-Up Interprocedural closure of the data structure graph over the
 // program.  This is useful for applications like pool allocation, but **not**
 // applications like alias analysis.
 //
 //===----------------------------------------------------------------------===//

 #include "llvm/Analysis/DataStructure.h"
 #include "llvm/Analysis/DSGraph.h"
 #include "llvm/Module.h"
 #include "Support/Statistic.h"
 #include "Support/hash_map"

 namespace {
   Statistic<> MaxSCC("budatastructure", "Maximum SCC Size in Call Graph");

   RegisterAnalysis<BUDataStructures>
   X("budatastructure", "Bottom-up Data Structure Analysis Closure");
 }

 using namespace DS;

 // isCompleteNode - Return true if we know all of the targets of this node, and
 // if the call sites are not external.
 //
 static inline bool isCompleteNode(DSNode *N) {
   if (N->NodeType & DSNode::Incomplete) return false;
   const std::vector<GlobalValue*> &Callees = N->getGlobals();
   for (unsigned i = 0, e = Callees.size(); i != e; ++i)
     if (Callees[i]->isExternal()) {
       GlobalValue &FI = cast<Function>(*Callees[i]);
       if (FI.getName() != "printf"  && FI.getName() != "sscanf" &&
           FI.getName() != "fprintf" && FI.getName() != "open" &&
           FI.getName() != "sprintf" && FI.getName() != "fputs" &&
           FI.getName() != "fscanf")
         return false;  // External function found...
     }
   return true;  // otherwise ok
 }

 struct CallSiteIterator {
   // FCs are the edges out of the current node are the call site targets...
   std::vector<DSCallSite> *FCs;
   unsigned CallSite;
   unsigned CallSiteEntry;

   CallSiteIterator(std::vector<DSCallSite> &CS) : FCs(&CS) {
     CallSite = 0; CallSiteEntry = 0;
     advanceToNextValid();
   }

   // End iterator ctor...
   CallSiteIterator(std::vector<DSCallSite> &CS, bool) : FCs(&CS) {
     CallSite = FCs->size(); CallSiteEntry = 0;
   }

   void advanceToNextValid() {
     while (CallSite < FCs->size()) {
       if (DSNode *CalleeNode = (*FCs)[CallSite].getCallee().getNode()) {
         if (CallSiteEntry || isCompleteNode(CalleeNode)) {
           const std::vector<GlobalValue*> &Callees = CalleeNode->getGlobals();

           if (CallSiteEntry < Callees.size())
             return;
         }
         CallSiteEntry = 0;
         ++CallSite;
       }
     }
   }
 public:
   static CallSiteIterator begin(DSGraph &G) { return G.getAuxFunctionCalls(); }
   static CallSiteIterator end(DSGraph &G) {
     return CallSiteIterator(G.getAuxFunctionCalls(), true);
   }
   static CallSiteIterator begin(std::vector<DSCallSite> &CSs) { return CSs; }
   static CallSiteIterator end(std::vector<DSCallSite> &CSs) {
     return CallSiteIterator(CSs, true);
   }
   bool operator==(const CallSiteIterator &CSI) const {
     return CallSite == CSI.CallSite && CallSiteEntry == CSI.CallSiteEntry;
   }
   bool operator!=(const CallSiteIterator &CSI) const { return !operator==(CSI);}

   unsigned getCallSiteIdx() const { return CallSite; }
   DSCallSite &getCallSite() const { return (*FCs)[CallSite]; }

   Function* operator*() const {
     DSNode *Node = (*FCs)[CallSite].getCallee().getNode();
     return cast<Function>(Node->getGlobals()[CallSiteEntry]);
   }

   CallSiteIterator& operator++() {                // Preincrement
     ++CallSiteEntry;
     advanceToNextValid();
     return *this;
   }
   CallSiteIterator operator++(int) { // Postincrement
     CallSiteIterator tmp = *this; ++*this; return tmp;
   }
 };


 // run - Calculate the bottom up data structure graphs for each function in the
 // program.
 //
 bool BUDataStructures::run(Module &M) {
   GlobalsGraph = new DSGraph();
   GlobalsGraph->setPrintAuxCalls();

   Function *MainFunc = M.getMainFunction();
   if (MainFunc)
     calculateReachableGraphs(MainFunc);

   // Calculate the graphs for any functions that are unreachable from main...
   for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
     if (!I->isExternal() && DSInfo.find(I) == DSInfo.end()) {
 #ifndef NDEBUG
       if (MainFunc)
         std::cerr << "*** Function unreachable from main: "
                   << I->getName() << "\n";
 #endif
       calculateReachableGraphs(I);    // Calculate all graphs...
     }
   return false;
 }

 void BUDataStructures::calculateReachableGraphs(Function *F) {
   std::vector<Function*> Stack;
   hash_map<Function*, unsigned> ValMap;
   unsigned NextID = 1;
   calculateGraphs(F, Stack, NextID, ValMap);
 }

 DSGraph &BUDataStructures::getOrCreateGraph(Function *F) {
   // Has the graph already been created?
   DSGraph *&Graph = DSInfo[F];
   if (Graph) return *Graph;

   // Copy the local version into DSInfo...
   Graph = new DSGraph(getAnalysis<LocalDataStructures>().getDSGraph(*F));

   Graph->setGlobalsGraph(GlobalsGraph);
   Graph->setPrintAuxCalls();

   // Start with a copy of the original call sites...
   Graph->getAuxFunctionCalls() = Graph->getFunctionCalls();
   return *Graph;
 }

 unsigned BUDataStructures::calculateGraphs(Function *F,
                                            std::vector<Function*> &Stack,
                                            unsigned &NextID,
                                      hash_map<Function*, unsigned> &ValMap) {
   assert(ValMap.find(F) == ValMap.end() && "Shouldn't revisit functions!");
   unsigned Min = NextID++, MyID = Min;
   ValMap[F] = Min;
   Stack.push_back(F);

   if (F->isExternal()) {   // sprintf, fprintf, sscanf, etc...
     // No callees!
     Stack.pop_back();
     ValMap[F] = ~0;
     return Min;
   }

   DSGraph &Graph = getOrCreateGraph(F);

   // The edges out of the current node are the call site targets...
   for (CallSiteIterator I = CallSiteIterator::begin(Graph),
          E = CallSiteIterator::end(Graph); I != E; ++I) {
     Function *Callee = *I;
     unsigned M;
     // Have we visited the destination function yet?
     hash_map<Function*, unsigned>::iterator It = ValMap.find(Callee);
     if (It == ValMap.end())  // No, visit it now.
       M = calculateGraphs(Callee, Stack, NextID, ValMap);
     else                    // Yes, get it's number.
       M = It->second;
     if (M < Min) Min = M;
   }

   assert(ValMap[F] == MyID && "SCC construction assumption wrong!");
   if (Min != MyID)
     return Min;         // This is part of a larger SCC!

   // If this is a new SCC, process it now.
   if (Stack.back() == F) {           // Special case the single "SCC" case here.
     DEBUG(std::cerr << "Visiting single node SCC #: " << MyID << " fn: "
                     << F->getName() << "\n");
     Stack.pop_back();
     DSGraph &G = calculateGraph(*F);

     if (MaxSCC < 1) MaxSCC = 1;

     // Should we revisit the graph?
     if (CallSiteIterator::begin(G) != CallSiteIterator::end(G)) {
       ValMap.erase(F);
       return calculateGraphs(F, Stack, NextID, ValMap);
     } else {
       ValMap[F] = ~0U;
     }
     return MyID;

   } else {
     // SCCFunctions - Keep track of the functions in the current SCC
     //
     hash_set<Function*> SCCFunctions;

     Function *NF;
     std::vector<Function*>::iterator FirstInSCC = Stack.end();
     do {
       NF = *--FirstInSCC;
       ValMap[NF] = ~0U;
       SCCFunctions.insert(NF);
     } while (NF != F);

     std::cerr << "Identified SCC #: " << MyID << " of size: "
               << (Stack.end()-FirstInSCC) << "\n";

     // Compute the Max SCC Size...
     if (MaxSCC < unsigned(Stack.end()-FirstInSCC))
       MaxSCC = Stack.end()-FirstInSCC;

     std::vector<Function*>::iterator I = Stack.end();
     do {
       --I;
 #ifndef NDEBUG
       /*DEBUG*/(std::cerr << "  Fn #" << (Stack.end()-I) << "/"
             << (Stack.end()-FirstInSCC) << " in SCC: "
             << (*I)->getName());
       DSGraph &G = getDSGraph(**I);
       std::cerr << " [" << G.getGraphSize() << "+"
                 << G.getAuxFunctionCalls().size() << "] ";
 #endif

       // Eliminate all call sites in the SCC that are not to functions that are
       // in the SCC.
       inlineNonSCCGraphs(**I, SCCFunctions);

 #ifndef NDEBUG
       std::cerr << "after Non-SCC's [" << G.getGraphSize() << "+"
                 << G.getAuxFunctionCalls().size() << "]\n";
 #endif
     } while (I != FirstInSCC);

     I = Stack.end();
     do {
       --I;
 #ifndef NDEBUG
       /*DEBUG*/(std::cerr << "  Fn #" << (Stack.end()-I) << "/"
             << (Stack.end()-FirstInSCC) << " in SCC: "
             << (*I)->getName());
       DSGraph &G = getDSGraph(**I);
       std::cerr << " [" << G.getGraphSize() << "+"
                 << G.getAuxFunctionCalls().size() << "] ";
 #endif
       // Inline all graphs into the SCC nodes...
       calculateSCCGraph(**I, SCCFunctions);

 #ifndef NDEBUG
       std::cerr << "after [" << G.getGraphSize() << "+"
                 << G.getAuxFunctionCalls().size() << "]\n";
 #endif
     } while (I != FirstInSCC);


     std::cerr << "DONE with SCC #: " << MyID << "\n";

     // We never have to revisit "SCC" processed functions...

     // Drop the stuff we don't need from the end of the stack
     Stack.erase(FirstInSCC, Stack.end());
     return MyID;
   }

   return MyID;  // == Min
 }


 // releaseMemory - If the pass pipeline is done with this pass, we can release
 // our memory... here...
 //
 void BUDataStructures::releaseMemory() {
   for (hash_map<const Function*, DSGraph*>::iterator I = DSInfo.begin(),
          E = DSInfo.end(); I != E; ++I)
     delete I->second;

   // Empty map so next time memory is released, data structures are not
   // re-deleted.
   DSInfo.clear();
   delete GlobalsGraph;
   GlobalsGraph = 0;
 }

 DSGraph &BUDataStructures::calculateGraph(Function &F) {
   DSGraph &Graph = getDSGraph(F);
   DEBUG(std::cerr << "  [BU] Calculating graph for: " << F.getName() << "\n");

   // Move our call site list into TempFCs so that inline call sites go into the
   // new call site list and doesn't invalidate our iterators!
   std::vector<DSCallSite> TempFCs;
   std::vector<DSCallSite> &AuxCallsList = Graph.getAuxFunctionCalls();
   TempFCs.swap(AuxCallsList);

   // Loop over all of the resolvable call sites
   unsigned LastCallSiteIdx = ~0U;
   for (CallSiteIterator I = CallSiteIterator::begin(TempFCs),
          E = CallSiteIterator::end(TempFCs); I != E; ++I) {
     // If we skipped over any call sites, they must be unresolvable, copy them
     // to the real call site list.
     LastCallSiteIdx++;
     for (; LastCallSiteIdx < I.getCallSiteIdx(); ++LastCallSiteIdx)
       AuxCallsList.push_back(TempFCs[LastCallSiteIdx]);
     LastCallSiteIdx = I.getCallSiteIdx();

     // Resolve the current call...
     Function *Callee = *I;
     DSCallSite &CS = I.getCallSite();

     if (Callee->isExternal()) {
       // Ignore this case, simple varargs functions we cannot stub out!
     } else if (Callee == &F) {
       // Self recursion... simply link up the formal arguments with the
       // actual arguments...
       DEBUG(std::cerr << "    Self Inlining: " << F.getName() << "\n");

       // Handle self recursion by resolving the arguments and return value
       Graph.mergeInGraph(CS, Graph, 0);

     } else {
       // Get the data structure graph for the called function.
       //
       DSGraph &GI = getDSGraph(*Callee);  // Graph to inline

       DEBUG(std::cerr << "    Inlining graph for " << Callee->getName()
             << "[" << GI.getGraphSize() << "+"
             << GI.getAuxFunctionCalls().size() << "] into: " << F.getName()
             << "[" << Graph.getGraphSize() << "+"
             << Graph.getAuxFunctionCalls().size() << "]\n");
 #if 0
       Graph.writeGraphToFile(std::cerr, "bu_" + F.getName() + "_before_" +
                              Callee->getName());
 #endif

       // Handle self recursion by resolving the arguments and return value
       Graph.mergeInGraph(CS, GI,
                          DSGraph::KeepModRefBits |
                          DSGraph::StripAllocaBit | DSGraph::DontCloneCallNodes);

 #if 0
       Graph.writeGraphToFile(std::cerr, "bu_" + F.getName() + "_after_" +
                              Callee->getName());
 #endif
     }
   }

   // Make sure to catch any leftover unresolvable calls...
   for (++LastCallSiteIdx; LastCallSiteIdx < TempFCs.size(); ++LastCallSiteIdx)
     AuxCallsList.push_back(TempFCs[LastCallSiteIdx]);

   TempFCs.clear();

   // Recompute the Incomplete markers.  If there are any function calls left
   // now that are complete, we must loop!
   Graph.maskIncompleteMarkers();
   Graph.markIncompleteNodes(DSGraph::MarkFormalArgs);
   // FIXME: materialize nodes from the globals graph as neccesary...
   Graph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);

   DEBUG(std::cerr << "  [BU] Done inlining: " << F.getName() << " ["
         << Graph.getGraphSize() << "+" << Graph.getAuxFunctionCalls().size()
         << "]\n");

   //Graph.writeGraphToFile(std::cerr, "bu_" + F.getName());

   return Graph;
 }


 // inlineNonSCCGraphs - This method is almost like the other two calculate graph
 // methods.  This one is used to inline function graphs (from functions outside
 // of the SCC) into functions in the SCC.  It is not supposed to touch functions
 // IN the SCC at all.
 //
 DSGraph &BUDataStructures::inlineNonSCCGraphs(Function &F,
                                              hash_set<Function*> &SCCFunctions){
   DSGraph &Graph = getDSGraph(F);
   DEBUG(std::cerr << "  [BU] Inlining Non-SCC graphs for: "
                   << F.getName() << "\n");

   // Move our call site list into TempFCs so that inline call sites go into the
   // new call site list and doesn't invalidate our iterators!
   std::vector<DSCallSite> TempFCs;
   std::vector<DSCallSite> &AuxCallsList = Graph.getAuxFunctionCalls();
   TempFCs.swap(AuxCallsList);

   // Loop over all of the resolvable call sites
   unsigned LastCallSiteIdx = ~0U;
   for (CallSiteIterator I = CallSiteIterator::begin(TempFCs),
          E = CallSiteIterator::end(TempFCs); I != E; ++I) {
     // If we skipped over any call sites, they must be unresolvable, copy them
     // to the real call site list.
     LastCallSiteIdx++;
     for (; LastCallSiteIdx < I.getCallSiteIdx(); ++LastCallSiteIdx)
       AuxCallsList.push_back(TempFCs[LastCallSiteIdx]);
     LastCallSiteIdx = I.getCallSiteIdx();

     // Resolve the current call...
     Function *Callee = *I;
     DSCallSite &CS = I.getCallSite();

     if (Callee->isExternal()) {
       // Ignore this case, simple varargs functions we cannot stub out!
     } else if (SCCFunctions.count(Callee)) {
       // Calling a function in the SCC, ignore it for now!
       DEBUG(std::cerr << "    SCC CallSite for: " << Callee->getName() << "\n");
       AuxCallsList.push_back(CS);
     } else {
       // Get the data structure graph for the called function.
       //
       DSGraph &GI = getDSGraph(*Callee);  // Graph to inline

       DEBUG(std::cerr << "    Inlining graph for " << Callee->getName()
             << "[" << GI.getGraphSize() << "+"
             << GI.getAuxFunctionCalls().size() << "] into: " << F.getName()
             << "[" << Graph.getGraphSize() << "+"
             << Graph.getAuxFunctionCalls().size() << "]\n");

       // Handle self recursion by resolving the arguments and return value
       Graph.mergeInGraph(CS, GI,
                          DSGraph::KeepModRefBits | DSGraph::StripAllocaBit |
                          DSGraph::DontCloneCallNodes);
     }
   }

   // Make sure to catch any leftover unresolvable calls...
   for (++LastCallSiteIdx; LastCallSiteIdx < TempFCs.size(); ++LastCallSiteIdx)
     AuxCallsList.push_back(TempFCs[LastCallSiteIdx]);

   TempFCs.clear();

   // Recompute the Incomplete markers.  If there are any function calls left
   // now that are complete, we must loop!
   Graph.maskIncompleteMarkers();
   Graph.markIncompleteNodes(DSGraph::MarkFormalArgs);
   Graph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);

   DEBUG(std::cerr << "  [BU] Done Non-SCC inlining: " << F.getName() << " ["
         << Graph.getGraphSize() << "+" << Graph.getAuxFunctionCalls().size()
         << "]\n");
   //Graph.writeGraphToFile(std::cerr, "nscc_" + F.getName());
   return Graph;
 }


 DSGraph &BUDataStructures::calculateSCCGraph(Function &F,
                                              hash_set<Function*> &SCCFunctions){
   DSGraph &Graph = getDSGraph(F);
   DEBUG(std::cerr << "  [BU] Calculating SCC graph for: " << F.getName()<<"\n");

   std::vector<DSCallSite> UnresolvableCalls;
   hash_map<Function*, DSCallSite> SCCCallSiteMap;
   std::vector<DSCallSite> &AuxCallsList = Graph.getAuxFunctionCalls();

   while (1) {  // Loop until we run out of resolvable call sites!
     // Move our call site list into TempFCs so that inline call sites go into
     // the new call site list and doesn't invalidate our iterators!
     std::vector<DSCallSite> TempFCs;
     TempFCs.swap(AuxCallsList);

     // Loop over all of the resolvable call sites
     unsigned LastCallSiteIdx = ~0U;
     CallSiteIterator I = CallSiteIterator::begin(TempFCs),
       E = CallSiteIterator::end(TempFCs);
     if (I == E) {
       TempFCs.swap(AuxCallsList);
       break;  // Done when no resolvable call sites exist
     }

     for (; I != E; ++I) {
       // If we skipped over any call sites, they must be unresolvable, copy them
       // to the unresolvable site list.
       LastCallSiteIdx++;
       for (; LastCallSiteIdx < I.getCallSiteIdx(); ++LastCallSiteIdx)
         UnresolvableCalls.push_back(TempFCs[LastCallSiteIdx]);
       LastCallSiteIdx = I.getCallSiteIdx();

       // Resolve the current call...
       Function *Callee = *I;
       DSCallSite &CS = I.getCallSite();

       if (Callee->isExternal()) {
         // Ignore this case, simple varargs functions we cannot stub out!
       } else if (Callee == &F) {
         // Self recursion... simply link up the formal arguments with the
         // actual arguments...
         DEBUG(std::cerr << "    Self Inlining: " << F.getName() << "\n");

         // Handle self recursion by resolving the arguments and return value
         Graph.mergeInGraph(CS, Graph, 0);
       } else if (SCCCallSiteMap.count(Callee)) {
         // We have already seen a call site in the SCC for this function, just
         // merge the two call sites together and we are done.
         SCCCallSiteMap.find(Callee)->second.mergeWith(CS);
       } else {
         // Get the data structure graph for the called function.
         //
         DSGraph &GI = getDSGraph(*Callee);  // Graph to inline
         DEBUG(std::cerr << "    Inlining graph for " << Callee->getName()
               << "[" << GI.getGraphSize() << "+"
               << GI.getAuxFunctionCalls().size() << "] into: " << F.getName()
               << "[" << Graph.getGraphSize() << "+"
               << Graph.getAuxFunctionCalls().size() << "]\n");

         // Handle self recursion by resolving the arguments and return value
         Graph.mergeInGraph(CS, GI,
                            DSGraph::KeepModRefBits | DSGraph::StripAllocaBit |
                            DSGraph::DontCloneCallNodes);

         if (SCCFunctions.count(Callee))
           SCCCallSiteMap.insert(std::make_pair(Callee, CS));
       }
     }

     // Make sure to catch any leftover unresolvable calls...
     for (++LastCallSiteIdx; LastCallSiteIdx < TempFCs.size(); ++LastCallSiteIdx)
       UnresolvableCalls.push_back(TempFCs[LastCallSiteIdx]);
   }

   // Reset the SCCCallSiteMap...
   SCCCallSiteMap.clear();

   AuxCallsList.insert(AuxCallsList.end(), UnresolvableCalls.begin(),
                       UnresolvableCalls.end());
   UnresolvableCalls.clear();


   // Recompute the Incomplete markers.  If there are any function calls left
   // now that are complete, we must loop!
   Graph.maskIncompleteMarkers();
   Graph.markIncompleteNodes(DSGraph::MarkFormalArgs);

   // FIXME: materialize nodes from the globals graph as neccesary...

   Graph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);

   DEBUG(std::cerr << "  [BU] Done inlining: " << F.getName() << " ["
         << Graph.getGraphSize() << "+" << Graph.getAuxFunctionCalls().size()
         << "]\n");
   //Graph.writeGraphToFile(std::cerr, "bu_" + F.getName());
   return Graph;
 }
	//===- BottomUpClosure.cpp - Compute bottom-up interprocedural closure ----===//
	//
	// This file implements the BUDataStructures class, which represents the
	// Bottom-Up Interprocedural closure of the data structure graph over the
	// program. This is useful for applications like pool allocation, but not
	// applications like alias analysis.
	//
	//===----------------------------------------------------------------------===//

	#include "llvm/Analysis/DataStructure.h"
	#include "llvm/Analysis/DSGraph.h"
	#include "llvm/Module.h"
	#include "Support/Statistic.h"
	#include "Support/hash_map"

	namespace {
	Statistic<> MaxSCC("budatastructure", "Maximum SCC Size in Call Graph");

	RegisterAnalysis<BUDataStructures>
	X("budatastructure", "Bottom-up Data Structure Analysis Closure");
	}

	using namespace DS;

	// isCompleteNode - Return true if we know all of the targets of this node, and
	// if the call sites are not external.
	//
	static inline bool isCompleteNode(DSNode *N) {
	if (N->NodeType & DSNode::Incomplete) return false;
	const std::vector<GlobalValue*> &Callees = N->getGlobals();
	for (unsigned i = 0, e = Callees.size(); i != e; ++i)
	if (Callees[i]->isExternal()) {
	GlobalValue &FI = cast<Function>(*Callees[i]);
	if (FI.getName() != "printf" && FI.getName() != "sscanf" &&
	FI.getName() != "fprintf" && FI.getName() != "open" &&
	FI.getName() != "sprintf" && FI.getName() != "fputs" &&
	FI.getName() != "fscanf")
	return false; // External function found...
	}
	return true; // otherwise ok
	}

	struct CallSiteIterator {
	// FCs are the edges out of the current node are the call site targets...
	std::vector<DSCallSite> *FCs;
	unsigned CallSite;
	unsigned CallSiteEntry;

	CallSiteIterator(std::vector<DSCallSite> &CS) : FCs(&CS) {
	CallSite = 0; CallSiteEntry = 0;
	advanceToNextValid();
	}

	// End iterator ctor...
	CallSiteIterator(std::vector<DSCallSite> &CS, bool) : FCs(&CS) {
	CallSite = FCs->size(); CallSiteEntry = 0;
	}

	void advanceToNextValid() {
	while (CallSite < FCs->size()) {
	if (DSNode CalleeNode = (FCs)[CallSite].getCallee().getNode()) {
	if (CallSiteEntry \|\| isCompleteNode(CalleeNode)) {
	const std::vector<GlobalValue*> &Callees = CalleeNode->getGlobals();

	if (CallSiteEntry < Callees.size())
	return;
	}
	CallSiteEntry = 0;
	++CallSite;
	}
	}
	}
	public:
	static CallSiteIterator begin(DSGraph &G) { return G.getAuxFunctionCalls(); }
	static CallSiteIterator end(DSGraph &G) {
	return CallSiteIterator(G.getAuxFunctionCalls(), true);
	}
	static CallSiteIterator begin(std::vector<DSCallSite> &CSs) { return CSs; }
	static CallSiteIterator end(std::vector<DSCallSite> &CSs) {
	return CallSiteIterator(CSs, true);
	}
	bool operator==(const CallSiteIterator &CSI) const {
	return CallSite == CSI.CallSite && CallSiteEntry == CSI.CallSiteEntry;
	}
	bool operator!=(const CallSiteIterator &CSI) const { return !operator==(CSI);}

	unsigned getCallSiteIdx() const { return CallSite; }
	DSCallSite &getCallSite() const { return (*FCs)[CallSite]; }

	Function* operator*() const {
	DSNode Node = (FCs)[CallSite].getCallee().getNode();
	return cast<Function>(Node->getGlobals()[CallSiteEntry]);
	}

	CallSiteIterator& operator++() { // Preincrement
	++CallSiteEntry;
	advanceToNextValid();
	return *this;
	}
	CallSiteIterator operator++(int) { // Postincrement
	CallSiteIterator tmp = this; ++this; return tmp;
	}
	};



	// run - Calculate the bottom up data structure graphs for each function in the
	// program.
	//
	bool BUDataStructures::run(Module &M) {
	GlobalsGraph = new DSGraph();
	GlobalsGraph->setPrintAuxCalls();

	Function *MainFunc = M.getMainFunction();
	if (MainFunc)
	calculateReachableGraphs(MainFunc);

	// Calculate the graphs for any functions that are unreachable from main...
	for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
	if (!I->isExternal() && DSInfo.find(I) == DSInfo.end()) {
	#ifndef NDEBUG
	if (MainFunc)
	std::cerr << "*** Function unreachable from main: "
	<< I->getName() << "\n";
	#endif
	calculateReachableGraphs(I); // Calculate all graphs...
	}
	return false;
	}

	void BUDataStructures::calculateReachableGraphs(Function *F) {
	std::vector<Function*> Stack;
	hash_map<Function*, unsigned> ValMap;
	unsigned NextID = 1;
	calculateGraphs(F, Stack, NextID, ValMap);
	}

	DSGraph &BUDataStructures::getOrCreateGraph(Function *F) {
	// Has the graph already been created?
	DSGraph *&Graph = DSInfo[F];
	if (Graph) return *Graph;

	// Copy the local version into DSInfo...
	Graph = new DSGraph(getAnalysis<LocalDataStructures>().getDSGraph(*F));

	Graph->setGlobalsGraph(GlobalsGraph);
	Graph->setPrintAuxCalls();

	// Start with a copy of the original call sites...
	Graph->getAuxFunctionCalls() = Graph->getFunctionCalls();
	return *Graph;
	}

	unsigned BUDataStructures::calculateGraphs(Function *F,
	std::vector<Function*> &Stack,
	unsigned &NextID,
	hash_map<Function*, unsigned> &ValMap) {
	assert(ValMap.find(F) == ValMap.end() && "Shouldn't revisit functions!");
	unsigned Min = NextID++, MyID = Min;
	ValMap[F] = Min;
	Stack.push_back(F);

	if (F->isExternal()) { // sprintf, fprintf, sscanf, etc...
	// No callees!
	Stack.pop_back();
	ValMap[F] = ~0;
	return Min;
	}

	DSGraph &Graph = getOrCreateGraph(F);

	// The edges out of the current node are the call site targets...
	for (CallSiteIterator I = CallSiteIterator::begin(Graph),
	E = CallSiteIterator::end(Graph); I != E; ++I) {
	Function Callee = I;
	unsigned M;
	// Have we visited the destination function yet?
	hash_map<Function*, unsigned>::iterator It = ValMap.find(Callee);
	if (It == ValMap.end()) // No, visit it now.
	M = calculateGraphs(Callee, Stack, NextID, ValMap);
	else // Yes, get it's number.
	M = It->second;
	if (M < Min) Min = M;
	}

	assert(ValMap[F] == MyID && "SCC construction assumption wrong!");
	if (Min != MyID)
	return Min; // This is part of a larger SCC!

	// If this is a new SCC, process it now.
	if (Stack.back() == F) { // Special case the single "SCC" case here.
	DEBUG(std::cerr << "Visiting single node SCC #: " << MyID << " fn: "
	<< F->getName() << "\n");
	Stack.pop_back();
	DSGraph &G = calculateGraph(*F);

	if (MaxSCC < 1) MaxSCC = 1;

	// Should we revisit the graph?
	if (CallSiteIterator::begin(G) != CallSiteIterator::end(G)) {
	ValMap.erase(F);
	return calculateGraphs(F, Stack, NextID, ValMap);
	} else {
	ValMap[F] = ~0U;
	}
	return MyID;

	} else {
	// SCCFunctions - Keep track of the functions in the current SCC
	//
	hash_set<Function*> SCCFunctions;

	Function *NF;
	std::vector<Function*>::iterator FirstInSCC = Stack.end();
	do {
	NF = *--FirstInSCC;
	ValMap[NF] = ~0U;
	SCCFunctions.insert(NF);
	} while (NF != F);

	std::cerr << "Identified SCC #: " << MyID << " of size: "
	<< (Stack.end()-FirstInSCC) << "\n";

	// Compute the Max SCC Size...
	if (MaxSCC < unsigned(Stack.end()-FirstInSCC))
	MaxSCC = Stack.end()-FirstInSCC;

	std::vector<Function*>::iterator I = Stack.end();
	do {
	--I;
	#ifndef NDEBUG
	/DEBUG/(std::cerr << " Fn #" << (Stack.end()-I) << "/"
	<< (Stack.end()-FirstInSCC) << " in SCC: "
	<< (*I)->getName());
	DSGraph &G = getDSGraph(**I);
	std::cerr << " [" << G.getGraphSize() << "+"
	<< G.getAuxFunctionCalls().size() << "] ";
	#endif

	// Eliminate all call sites in the SCC that are not to functions that are
	// in the SCC.
	inlineNonSCCGraphs(**I, SCCFunctions);

	#ifndef NDEBUG
	std::cerr << "after Non-SCC's [" << G.getGraphSize() << "+"
	<< G.getAuxFunctionCalls().size() << "]\n";
	#endif
	} while (I != FirstInSCC);

	I = Stack.end();
	do {
	--I;
	#ifndef NDEBUG
	/DEBUG/(std::cerr << " Fn #" << (Stack.end()-I) << "/"
	<< (Stack.end()-FirstInSCC) << " in SCC: "
	<< (*I)->getName());
	DSGraph &G = getDSGraph(**I);
	std::cerr << " [" << G.getGraphSize() << "+"
	<< G.getAuxFunctionCalls().size() << "] ";
	#endif
	// Inline all graphs into the SCC nodes...
	calculateSCCGraph(**I, SCCFunctions);

	#ifndef NDEBUG
	std::cerr << "after [" << G.getGraphSize() << "+"
	<< G.getAuxFunctionCalls().size() << "]\n";
	#endif
	} while (I != FirstInSCC);


	std::cerr << "DONE with SCC #: " << MyID << "\n";

	// We never have to revisit "SCC" processed functions...

	// Drop the stuff we don't need from the end of the stack
	Stack.erase(FirstInSCC, Stack.end());
	return MyID;
	}

	return MyID; // == Min
	}


	// releaseMemory - If the pass pipeline is done with this pass, we can release
	// our memory... here...
	//
	void BUDataStructures::releaseMemory() {
	for (hash_map<const Function, DSGraph>::iterator I = DSInfo.begin(),
	E = DSInfo.end(); I != E; ++I)
	delete I->second;

	// Empty map so next time memory is released, data structures are not
	// re-deleted.
	DSInfo.clear();
	delete GlobalsGraph;
	GlobalsGraph = 0;
	}

	DSGraph &BUDataStructures::calculateGraph(Function &F) {
	DSGraph &Graph = getDSGraph(F);
	DEBUG(std::cerr << " [BU] Calculating graph for: " << F.getName() << "\n");

	// Move our call site list into TempFCs so that inline call sites go into the
	// new call site list and doesn't invalidate our iterators!
	std::vector<DSCallSite> TempFCs;
	std::vector<DSCallSite> &AuxCallsList = Graph.getAuxFunctionCalls();
	TempFCs.swap(AuxCallsList);

	// Loop over all of the resolvable call sites
	unsigned LastCallSiteIdx = ~0U;
	for (CallSiteIterator I = CallSiteIterator::begin(TempFCs),
	E = CallSiteIterator::end(TempFCs); I != E; ++I) {
	// If we skipped over any call sites, they must be unresolvable, copy them
	// to the real call site list.
	LastCallSiteIdx++;
	for (; LastCallSiteIdx < I.getCallSiteIdx(); ++LastCallSiteIdx)
	AuxCallsList.push_back(TempFCs[LastCallSiteIdx]);
	LastCallSiteIdx = I.getCallSiteIdx();

	// Resolve the current call...
	Function Callee = I;
	DSCallSite &CS = I.getCallSite();

	if (Callee->isExternal()) {
	// Ignore this case, simple varargs functions we cannot stub out!
	} else if (Callee == &F) {
	// Self recursion... simply link up the formal arguments with the
	// actual arguments...
	DEBUG(std::cerr << " Self Inlining: " << F.getName() << "\n");

	// Handle self recursion by resolving the arguments and return value
	Graph.mergeInGraph(CS, Graph, 0);

	} else {
	// Get the data structure graph for the called function.
	//
	DSGraph &GI = getDSGraph(*Callee); // Graph to inline

	DEBUG(std::cerr << " Inlining graph for " << Callee->getName()
	<< "[" << GI.getGraphSize() << "+"
	<< GI.getAuxFunctionCalls().size() << "] into: " << F.getName()
	<< "[" << Graph.getGraphSize() << "+"
	<< Graph.getAuxFunctionCalls().size() << "]\n");
	#if 0
	Graph.writeGraphToFile(std::cerr, "bu_" + F.getName() + "_before_" +
	Callee->getName());
	#endif

	// Handle self recursion by resolving the arguments and return value
	Graph.mergeInGraph(CS, GI,
	DSGraph::KeepModRefBits \|
	DSGraph::StripAllocaBit \| DSGraph::DontCloneCallNodes);

	#if 0
	Graph.writeGraphToFile(std::cerr, "bu_" + F.getName() + "_after_" +
	Callee->getName());
	#endif
	}
	}

	// Make sure to catch any leftover unresolvable calls...
	for (++LastCallSiteIdx; LastCallSiteIdx < TempFCs.size(); ++LastCallSiteIdx)
	AuxCallsList.push_back(TempFCs[LastCallSiteIdx]);

	TempFCs.clear();

	// Recompute the Incomplete markers. If there are any function calls left
	// now that are complete, we must loop!
	Graph.maskIncompleteMarkers();
	Graph.markIncompleteNodes(DSGraph::MarkFormalArgs);
	// FIXME: materialize nodes from the globals graph as neccesary...
	Graph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);

	DEBUG(std::cerr << " [BU] Done inlining: " << F.getName() << " ["
	<< Graph.getGraphSize() << "+" << Graph.getAuxFunctionCalls().size()
	<< "]\n");

	//Graph.writeGraphToFile(std::cerr, "bu_" + F.getName());

	return Graph;
	}


	// inlineNonSCCGraphs - This method is almost like the other two calculate graph
	// methods. This one is used to inline function graphs (from functions outside
	// of the SCC) into functions in the SCC. It is not supposed to touch functions
	// IN the SCC at all.
	//
	DSGraph &BUDataStructures::inlineNonSCCGraphs(Function &F,
	hash_set<Function*> &SCCFunctions){
	DSGraph &Graph = getDSGraph(F);
	DEBUG(std::cerr << " [BU] Inlining Non-SCC graphs for: "
	<< F.getName() << "\n");

	// Move our call site list into TempFCs so that inline call sites go into the
	// new call site list and doesn't invalidate our iterators!
	std::vector<DSCallSite> TempFCs;
	std::vector<DSCallSite> &AuxCallsList = Graph.getAuxFunctionCalls();
	TempFCs.swap(AuxCallsList);

	// Loop over all of the resolvable call sites
	unsigned LastCallSiteIdx = ~0U;
	for (CallSiteIterator I = CallSiteIterator::begin(TempFCs),
	E = CallSiteIterator::end(TempFCs); I != E; ++I) {
	// If we skipped over any call sites, they must be unresolvable, copy them
	// to the real call site list.
	LastCallSiteIdx++;
	for (; LastCallSiteIdx < I.getCallSiteIdx(); ++LastCallSiteIdx)
	AuxCallsList.push_back(TempFCs[LastCallSiteIdx]);
	LastCallSiteIdx = I.getCallSiteIdx();

	// Resolve the current call...
	Function Callee = I;
	DSCallSite &CS = I.getCallSite();

	if (Callee->isExternal()) {
	// Ignore this case, simple varargs functions we cannot stub out!
	} else if (SCCFunctions.count(Callee)) {
	// Calling a function in the SCC, ignore it for now!
	DEBUG(std::cerr << " SCC CallSite for: " << Callee->getName() << "\n");
	AuxCallsList.push_back(CS);
	} else {
	// Get the data structure graph for the called function.
	//
	DSGraph &GI = getDSGraph(*Callee); // Graph to inline

	DEBUG(std::cerr << " Inlining graph for " << Callee->getName()
	<< "[" << GI.getGraphSize() << "+"
	<< GI.getAuxFunctionCalls().size() << "] into: " << F.getName()
	<< "[" << Graph.getGraphSize() << "+"
	<< Graph.getAuxFunctionCalls().size() << "]\n");

	// Handle self recursion by resolving the arguments and return value
	Graph.mergeInGraph(CS, GI,
	DSGraph::KeepModRefBits \| DSGraph::StripAllocaBit \|
	DSGraph::DontCloneCallNodes);
	}
	}

	// Make sure to catch any leftover unresolvable calls...
	for (++LastCallSiteIdx; LastCallSiteIdx < TempFCs.size(); ++LastCallSiteIdx)
	AuxCallsList.push_back(TempFCs[LastCallSiteIdx]);

	TempFCs.clear();

	// Recompute the Incomplete markers. If there are any function calls left
	// now that are complete, we must loop!
	Graph.maskIncompleteMarkers();
	Graph.markIncompleteNodes(DSGraph::MarkFormalArgs);
	Graph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);

	DEBUG(std::cerr << " [BU] Done Non-SCC inlining: " << F.getName() << " ["
	<< Graph.getGraphSize() << "+" << Graph.getAuxFunctionCalls().size()
	<< "]\n");
	//Graph.writeGraphToFile(std::cerr, "nscc_" + F.getName());
	return Graph;
	}


	DSGraph &BUDataStructures::calculateSCCGraph(Function &F,
	hash_set<Function*> &SCCFunctions){
	DSGraph &Graph = getDSGraph(F);
	DEBUG(std::cerr << " [BU] Calculating SCC graph for: " << F.getName()<<"\n");

	std::vector<DSCallSite> UnresolvableCalls;
	hash_map<Function*, DSCallSite> SCCCallSiteMap;
	std::vector<DSCallSite> &AuxCallsList = Graph.getAuxFunctionCalls();

	while (1) { // Loop until we run out of resolvable call sites!
	// Move our call site list into TempFCs so that inline call sites go into
	// the new call site list and doesn't invalidate our iterators!
	std::vector<DSCallSite> TempFCs;
	TempFCs.swap(AuxCallsList);

	// Loop over all of the resolvable call sites
	unsigned LastCallSiteIdx = ~0U;
	CallSiteIterator I = CallSiteIterator::begin(TempFCs),
	E = CallSiteIterator::end(TempFCs);
	if (I == E) {
	TempFCs.swap(AuxCallsList);
	break; // Done when no resolvable call sites exist
	}

	for (; I != E; ++I) {
	// If we skipped over any call sites, they must be unresolvable, copy them
	// to the unresolvable site list.
	LastCallSiteIdx++;
	for (; LastCallSiteIdx < I.getCallSiteIdx(); ++LastCallSiteIdx)
	UnresolvableCalls.push_back(TempFCs[LastCallSiteIdx]);
	LastCallSiteIdx = I.getCallSiteIdx();

	// Resolve the current call...
	Function Callee = I;
	DSCallSite &CS = I.getCallSite();

	if (Callee->isExternal()) {
	// Ignore this case, simple varargs functions we cannot stub out!
	} else if (Callee == &F) {
	// Self recursion... simply link up the formal arguments with the
	// actual arguments...
	DEBUG(std::cerr << " Self Inlining: " << F.getName() << "\n");

	// Handle self recursion by resolving the arguments and return value
	Graph.mergeInGraph(CS, Graph, 0);
	} else if (SCCCallSiteMap.count(Callee)) {
	// We have already seen a call site in the SCC for this function, just
	// merge the two call sites together and we are done.
	SCCCallSiteMap.find(Callee)->second.mergeWith(CS);
	} else {
	// Get the data structure graph for the called function.
	//
	DSGraph &GI = getDSGraph(*Callee); // Graph to inline
	DEBUG(std::cerr << " Inlining graph for " << Callee->getName()
	<< "[" << GI.getGraphSize() << "+"
	<< GI.getAuxFunctionCalls().size() << "] into: " << F.getName()
	<< "[" << Graph.getGraphSize() << "+"
	<< Graph.getAuxFunctionCalls().size() << "]\n");

	// Handle self recursion by resolving the arguments and return value
	Graph.mergeInGraph(CS, GI,
	DSGraph::KeepModRefBits \| DSGraph::StripAllocaBit \|
	DSGraph::DontCloneCallNodes);

	if (SCCFunctions.count(Callee))
	SCCCallSiteMap.insert(std::make_pair(Callee, CS));
	}
	}

	// Make sure to catch any leftover unresolvable calls...
	for (++LastCallSiteIdx; LastCallSiteIdx < TempFCs.size(); ++LastCallSiteIdx)
	UnresolvableCalls.push_back(TempFCs[LastCallSiteIdx]);
	}

	// Reset the SCCCallSiteMap...
	SCCCallSiteMap.clear();

	AuxCallsList.insert(AuxCallsList.end(), UnresolvableCalls.begin(),
	UnresolvableCalls.end());
	UnresolvableCalls.clear();


	// Recompute the Incomplete markers. If there are any function calls left
	// now that are complete, we must loop!
	Graph.maskIncompleteMarkers();
	Graph.markIncompleteNodes(DSGraph::MarkFormalArgs);

	// FIXME: materialize nodes from the globals graph as neccesary...

	Graph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);

	DEBUG(std::cerr << " [BU] Done inlining: " << F.getName() << " ["
	<< Graph.getGraphSize() << "+" << Graph.getAuxFunctionCalls().size()
	<< "]\n");
	//Graph.writeGraphToFile(std::cerr, "bu_" + F.getName());
	return Graph;
	}