[llvm-commits] [parallel] CVS: llvm/lib/Analysis/DataStructure/BottomUpClosure.cpp CompleteBottomUp.cpp DataStructure.cpp DataStructureAA.cpp GraphChecker.cpp Local.cpp Printer.cpp Steensgaard.cpp TopDownClosure.cpp

Misha Brukman brukman at cs.uiuc.edu
Mon Mar 1 18:04:57 PST 2004


Changes in directory llvm/lib/Analysis/DataStructure:

BottomUpClosure.cpp updated: 1.70 -> 1.70.4.1
CompleteBottomUp.cpp updated: 1.3 -> 1.3.4.1
DataStructure.cpp updated: 1.131 -> 1.131.4.1
DataStructureAA.cpp updated: 1.13 -> 1.13.4.1
GraphChecker.cpp updated: 1.10 -> 1.10.4.1
Local.cpp updated: 1.74 -> 1.74.4.1
Printer.cpp updated: 1.62 -> 1.62.4.1
Steensgaard.cpp updated: 1.35 -> 1.35.4.1
TopDownClosure.cpp updated: 1.60 -> 1.60.4.1

---
Log message:

Merge from trunk

---
Diffs of the changes:  (+1053 -544)

Index: llvm/lib/Analysis/DataStructure/BottomUpClosure.cpp
diff -u llvm/lib/Analysis/DataStructure/BottomUpClosure.cpp:1.70 llvm/lib/Analysis/DataStructure/BottomUpClosure.cpp:1.70.4.1
--- llvm/lib/Analysis/DataStructure/BottomUpClosure.cpp:1.70	Wed Nov 12 23:04:19 2003
+++ llvm/lib/Analysis/DataStructure/BottomUpClosure.cpp	Mon Mar  1 17:58:12 2004
@@ -63,6 +63,7 @@
   // nodes at the end of the BU phase should make things that they point to
   // incomplete in the globals graph.
   // 
+  GlobalsGraph->removeTriviallyDeadNodes();
   GlobalsGraph->maskIncompleteMarkers();
   return false;
 }
@@ -152,7 +153,7 @@
   } else {
     // SCCFunctions - Keep track of the functions in the current SCC
     //
-    hash_set<Function*> SCCFunctions;
+    hash_set<DSGraph*> SCCGraphs;
 
     Function *NF;
     std::vector<Function*>::iterator FirstInSCC = Stack.end();
@@ -160,42 +161,44 @@
     do {
       NF = *--FirstInSCC;
       ValMap[NF] = ~0U;
-      SCCFunctions.insert(NF);
 
       // Figure out which graph is the largest one, in order to speed things up
       // a bit in situations where functions in the SCC have widely different
       // graph sizes.
       DSGraph &NFGraph = getDSGraph(*NF);
+      SCCGraphs.insert(&NFGraph);
       if (!SCCGraph || SCCGraph->getGraphSize() < NFGraph.getGraphSize())
         SCCGraph = &NFGraph;
     } while (NF != F);
 
     std::cerr << "Calculating graph for SCC #: " << MyID << " of size: "
-              << SCCFunctions.size() << "\n";
+              << SCCGraphs.size() << "\n";
 
     // Compute the Max SCC Size...
-    if (MaxSCC < SCCFunctions.size())
-      MaxSCC = SCCFunctions.size();
+    if (MaxSCC < SCCGraphs.size())
+      MaxSCC = SCCGraphs.size();
 
     // First thing first, collapse all of the DSGraphs into a single graph for
     // the entire SCC.  We computed the largest graph, so clone all of the other
     // (smaller) graphs into it.  Discard all of the old graphs.
     //
-    for (hash_set<Function*>::iterator I = SCCFunctions.begin(),
-           E = SCCFunctions.end(); I != E; ++I) {
-      DSGraph &G = getDSGraph(**I);
+    for (hash_set<DSGraph*>::iterator I = SCCGraphs.begin(),
+           E = SCCGraphs.end(); I != E; ++I) {
+      DSGraph &G = **I;
       if (&G != SCCGraph) {
         DSGraph::NodeMapTy NodeMap;
         SCCGraph->cloneInto(G, SCCGraph->getScalarMap(),
-                            SCCGraph->getReturnNodes(), NodeMap, 0);
+                            SCCGraph->getReturnNodes(), NodeMap);
         // Update the DSInfo map and delete the old graph...
-        DSInfo[*I] = SCCGraph;
+        for (DSGraph::ReturnNodesTy::iterator I = G.getReturnNodes().begin(),
+               E = G.getReturnNodes().end(); I != E; ++I)
+          DSInfo[I->first] = SCCGraph;
         delete &G;
       }
     }
 
     // Clean up the graph before we start inlining a bunch again...
-    SCCGraph->removeTriviallyDeadNodes();
+    SCCGraph->removeDeadNodes(DSGraph::RemoveUnreachableGlobals);
 
     // Now that we have one big happy family, resolve all of the call sites in
     // the graph...
@@ -276,13 +279,15 @@
       //
       DSGraph &GI = getDSGraph(*Callee);  // Graph to inline
       
+      if (Callee->getName() == "bc_raise")
+        std::cerr << "HERE!\n";
+
       DEBUG(std::cerr << "    Inlining graph for " << Callee->getName()
             << "[" << GI.getGraphSize() << "+"
             << GI.getAuxFunctionCalls().size() << "] into '"
             << Graph.getFunctionNames() << "' [" << Graph.getGraphSize() << "+"
             << Graph.getAuxFunctionCalls().size() << "]\n");
       
-      // Handle self recursion by resolving the arguments and return value
       Graph.mergeInGraph(CS, *Callee, GI,
                          DSGraph::KeepModRefBits | 
                          DSGraph::StripAllocaBit | DSGraph::DontCloneCallNodes);
@@ -301,18 +306,25 @@
 
   TempFCs.clear();
 
-  // Re-materialize nodes from the globals graph.
-  // Do not ignore globals inlined from callees -- they are not up-to-date!
-  Graph.getInlinedGlobals().clear();
-  Graph.updateFromGlobalGraph();
-
   // Recompute the Incomplete markers
+  assert(Graph.getInlinedGlobals().empty());
   Graph.maskIncompleteMarkers();
   Graph.markIncompleteNodes(DSGraph::MarkFormalArgs);
 
   // Delete dead nodes.  Treat globals that are unreachable but that can
   // reach live nodes as live.
   Graph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);
+
+  // When this graph is finalized, clone the globals in the graph into the
+  // globals graph to make sure it has everything, from all graphs.
+  DSScalarMap &MainSM = Graph.getScalarMap();
+  ReachabilityCloner RC(*GlobalsGraph, Graph, DSGraph::StripAllocaBit);
+
+  // Clone everything reachable from globals in the "main" graph into the
+  // globals graph.
+  for (DSScalarMap::global_iterator I = MainSM.global_begin(),
+         E = MainSM.global_end(); I != E; ++I) 
+    RC.getClonedNH(MainSM[*I]);
 
   //Graph.writeGraphToFile(std::cerr, "bu_" + F.getName());
 }


Index: llvm/lib/Analysis/DataStructure/CompleteBottomUp.cpp
diff -u llvm/lib/Analysis/DataStructure/CompleteBottomUp.cpp:1.3 llvm/lib/Analysis/DataStructure/CompleteBottomUp.cpp:1.3.4.1
--- llvm/lib/Analysis/DataStructure/CompleteBottomUp.cpp:1.3	Thu Nov 13 12:48:11 2003
+++ llvm/lib/Analysis/DataStructure/CompleteBottomUp.cpp	Mon Mar  1 17:58:12 2004
@@ -77,6 +77,7 @@
     if (!I->isExternal() && !DSInfo.count(I))
       calculateSCCGraphs(getOrCreateGraph(*I), Stack, NextID, ValMap);
 
+  GlobalsGraph->removeTriviallyDeadNodes();
   return false;
 }
 
@@ -141,7 +142,7 @@
     ValMap[NG] = ~0U;
 
     DSGraph::NodeMapTy NodeMap;
-    FG.cloneInto(*NG, FG.getScalarMap(), FG.getReturnNodes(), NodeMap, 0);
+    FG.cloneInto(*NG, FG.getScalarMap(), FG.getReturnNodes(), NodeMap);
 
     // Update the DSInfo map and delete the old graph...
     for (DSGraph::ReturnNodesTy::iterator I = NG->getReturnNodes().begin();
@@ -167,6 +168,7 @@
 /// processGraph - Process the BU graphs for the program in bottom-up order on
 /// the SCC of the __ACTUAL__ call graph.  This builds "complete" BU graphs.
 void CompleteBUDataStructures::processGraph(DSGraph &G) {
+
   // The edges out of the current node are the call site targets...
   for (unsigned i = 0, e = G.getFunctionCalls().size(); i != e; ++i) {
     const DSCallSite &CS = G.getFunctionCalls()[i];
@@ -191,12 +193,8 @@
     }
   }
 
-  // Re-materialize nodes from the globals graph.
-  // Do not ignore globals inlined from callees -- they are not up-to-date!
-  G.getInlinedGlobals().clear();
-  G.updateFromGlobalGraph();
-
   // Recompute the Incomplete markers
+  assert(G.getInlinedGlobals().empty());
   G.maskIncompleteMarkers();
   G.markIncompleteNodes(DSGraph::MarkFormalArgs);
 


Index: llvm/lib/Analysis/DataStructure/DataStructure.cpp
diff -u llvm/lib/Analysis/DataStructure/DataStructure.cpp:1.131 llvm/lib/Analysis/DataStructure/DataStructure.cpp:1.131.4.1
--- llvm/lib/Analysis/DataStructure/DataStructure.cpp:1.131	Wed Nov 12 17:11:14 2003
+++ llvm/lib/Analysis/DataStructure/DataStructure.cpp	Mon Mar  1 17:58:12 2004
@@ -13,10 +13,12 @@
 
 #include "llvm/Analysis/DSGraph.h"
 #include "llvm/Function.h"
+#include "llvm/GlobalVariable.h"
 #include "llvm/iOther.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Target/TargetData.h"
 #include "llvm/Assembly/Writer.h"
+#include "Support/CommandLine.h"
 #include "Support/Debug.h"
 #include "Support/STLExtras.h"
 #include "Support/Statistic.h"
@@ -25,14 +27,25 @@
 using namespace llvm;
 
 namespace {
-  Statistic<> NumFolds          ("dsnode", "Number of nodes completely folded");
-  Statistic<> NumCallNodesMerged("dsnode", "Number of call nodes merged");
+  Statistic<> NumFolds          ("dsa", "Number of nodes completely folded");
+  Statistic<> NumCallNodesMerged("dsa", "Number of call nodes merged");
+  Statistic<> NumNodeAllocated  ("dsa", "Number of nodes allocated");
+  Statistic<> NumDNE            ("dsa", "Number of nodes removed by reachability");
+  Statistic<> NumTrivialDNE     ("dsa", "Number of nodes trivially removed");
+  Statistic<> NumTrivialGlobalDNE("dsa", "Number of globals trivially removed");
 };
 
+#if 1
+#define TIME_REGION(VARNAME, DESC) \
+   NamedRegionTimer VARNAME(DESC)
+#else
+#define TIME_REGION(VARNAME, DESC)
+#endif
+
 using namespace DS;
 
 DSNode *DSNodeHandle::HandleForwarding() const {
-  assert(!N->ForwardNH.isNull() && "Can only be invoked if forwarding!");
+  assert(N->isForwarding() && "Can only be invoked if forwarding!");
 
   // Handle node forwarding here!
   DSNode *Next = N->ForwardNH.getNode();  // Cause recursive shrinkage
@@ -60,14 +73,20 @@
   : NumReferrers(0), Size(0), ParentGraph(G), Ty(Type::VoidTy), NodeType(0) {
   // Add the type entry if it is specified...
   if (T) mergeTypeInfo(T, 0);
-  G->getNodes().push_back(this);
+  if (G) G->addNode(this);
+  ++NumNodeAllocated;
 }
 
 // DSNode copy constructor... do not copy over the referrers list!
-DSNode::DSNode(const DSNode &N, DSGraph *G)
+DSNode::DSNode(const DSNode &N, DSGraph *G, bool NullLinks)
   : NumReferrers(0), Size(N.Size), ParentGraph(G),
-    Ty(N.Ty), Links(N.Links), Globals(N.Globals), NodeType(N.NodeType) {
-  G->getNodes().push_back(this);
+    Ty(N.Ty), Globals(N.Globals), NodeType(N.NodeType) {
+  if (!NullLinks)
+    Links = N.Links;
+  else
+    Links.resize(N.Links.size()); // Create the appropriate number of null links
+  G->addNode(this);
+  ++NumNodeAllocated;
 }
 
 /// getTargetData - Get the target data object used to construct this node.
@@ -83,9 +102,9 @@
          "Node not OK!");
 
   assert(ParentGraph && "Node has no parent?");
-  const DSGraph::ScalarMapTy &SM = ParentGraph->getScalarMap();
+  const DSScalarMap &SM = ParentGraph->getScalarMap();
   for (unsigned i = 0, e = Globals.size(); i != e; ++i) {
-    assert(SM.find(Globals[i]) != SM.end());
+    assert(SM.count(Globals[i]));
     assert(SM.find(Globals[i])->second.getNode() == this);
   }
 }
@@ -104,6 +123,10 @@
   NodeType = DEAD;
   Size = 0;
   Ty = Type::VoidTy;
+
+  // Remove this node from the parent graph's Nodes list.
+  ParentGraph->unlinkNode(this);  
+  ParentGraph = 0;
 }
 
 // addGlobal - Add an entry for a global value to the Globals list.  This also
@@ -131,26 +154,40 @@
 
   ++NumFolds;
 
-  // Create the node we are going to forward to...
-  DSNode *DestNode = new DSNode(0, ParentGraph);
-  DestNode->NodeType = NodeType|DSNode::Array;
-  DestNode->Ty = Type::VoidTy;
-  DestNode->Size = 1;
-  DestNode->Globals.swap(Globals);
-
-  // Start forwarding to the destination node...
-  forwardNode(DestNode, 0);
-  
-  if (Links.size()) {
-    DestNode->Links.push_back(Links[0]);
-    DSNodeHandle NH(DestNode);
-
-    // If we have links, merge all of our outgoing links together...
-    for (unsigned i = Links.size()-1; i != 0; --i)
-      NH.getNode()->Links[0].mergeWith(Links[i]);
-    Links.clear();
+  // If this node has a size that is <= 1, we don't need to create a forwarding
+  // node.
+  if (getSize() <= 1) {
+    NodeType |= DSNode::Array;
+    Ty = Type::VoidTy;
+    Size = 1;
+    assert(Links.size() <= 1 && "Size is 1, but has more links?");
+    Links.resize(1);
   } else {
-    DestNode->Links.resize(1);
+    // Create the node we are going to forward to.  This is required because
+    // some referrers may have an offset that is > 0.  By forcing them to
+    // forward, the forwarder has the opportunity to correct the offset.
+    DSNode *DestNode = new DSNode(0, ParentGraph);
+    DestNode->NodeType = NodeType|DSNode::Array;
+    DestNode->Ty = Type::VoidTy;
+    DestNode->Size = 1;
+    DestNode->Globals.swap(Globals);
+    
+    // Start forwarding to the destination node...
+    forwardNode(DestNode, 0);
+    
+    if (!Links.empty()) {
+      DestNode->Links.reserve(1);
+      
+      DSNodeHandle NH(DestNode);
+      DestNode->Links.push_back(Links[0]);
+      
+      // If we have links, merge all of our outgoing links together...
+      for (unsigned i = Links.size()-1; i != 0; --i)
+        NH.getNode()->Links[0].mergeWith(Links[i]);
+      Links.clear();
+    } else {
+      DestNode->Links.resize(1);
+    }
   }
 }
 
@@ -201,7 +238,7 @@
         StackState &SS = Stack.back();
         if (const StructType *ST = dyn_cast<StructType>(SS.Ty)) {
           ++SS.Idx;
-          if (SS.Idx != ST->getElementTypes().size()) {
+          if (SS.Idx != ST->getNumElements()) {
             const StructLayout *SL = TD.getStructLayout(ST);
             SS.Offset += SL->MemberOffsets[SS.Idx]-SL->MemberOffsets[SS.Idx-1];
             return;
@@ -226,14 +263,14 @@
       while (!Stack.empty() && !Stack.back().Ty->isFirstClassType()) {
         StackState &SS = Stack.back();
         if (const StructType *ST = dyn_cast<StructType>(SS.Ty)) {
-          if (ST->getElementTypes().empty()) {
+          if (ST->getNumElements() == 0) {
             assert(SS.Idx == 0);
             PopStackAndAdvance();
           } else {
             // Step into the structure...
-            assert(SS.Idx < ST->getElementTypes().size());
+            assert(SS.Idx < ST->getNumElements());
             const StructLayout *SL = TD.getStructLayout(ST);
-            Stack.push_back(StackState(ST->getElementTypes()[SS.Idx],
+            Stack.push_back(StackState(ST->getElementType(SS.Idx),
                                        SS.Offset+SL->MemberOffsets[SS.Idx]));
           }
         } else {
@@ -403,7 +440,7 @@
         /* empty */;
 
       // The offset we are looking for must be in the i'th element...
-      SubType = STy->getElementTypes()[i];
+      SubType = STy->getElementType(i);
       O += SL.MemberOffsets[i];
       break;
     }
@@ -425,6 +462,10 @@
   // If we found our type exactly, early exit
   if (SubType == NewTy) return false;
 
+  // Differing function types don't require us to merge.  They are not values anyway.
+  if (isa<FunctionType>(SubType) &&
+      isa<FunctionType>(NewTy)) return false;
+
   unsigned SubTypeSize = SubType->isSized() ? TD.getTypeSize(SubType) : 0;
 
   // Ok, we are getting desperate now.  Check for physical subtyping, where we
@@ -452,7 +493,7 @@
         NextPadSize = SL.MemberOffsets[1];
       else
         NextPadSize = SubTypeSize;
-      NextSubType = STy->getElementTypes()[0];
+      NextSubType = STy->getElementType(0);
       NextSubTypeSize = TD.getTypeSize(NextSubType);
       break;
     }
@@ -516,10 +557,10 @@
 // can cause merging of nodes in the graph.
 //
 void DSNode::addEdgeTo(unsigned Offset, const DSNodeHandle &NH) {
-  if (NH.getNode() == 0) return;       // Nothing to do
+  if (NH.isNull()) return;       // Nothing to do
 
   DSNodeHandle &ExistingEdge = getLink(Offset);
-  if (ExistingEdge.getNode()) {
+  if (!ExistingEdge.isNull()) {
     // Merge the two nodes...
     ExistingEdge.mergeWith(NH);
   } else {                             // No merging to perform...
@@ -571,8 +612,11 @@
   }
 }
 
+void DSNode::mergeGlobals(const std::vector<GlobalValue*> &RHS) {
+  MergeSortedVectors(Globals, RHS);
+}
 
-// MergeNodes() - Helper function for DSNode::mergeWith().
+// MergeNodes - Helper function for DSNode::mergeWith().
 // This function does the hard work of merging two nodes, CurNodeH
 // and NH after filtering out trivial cases and making sure that
 // CurNodeH.offset >= NH.offset.
@@ -635,7 +679,7 @@
   if (CurNodeH.getNode() == N || N == 0) return;
   assert(!CurNodeH.getNode()->isDeadNode());
 
-  // Merge the NodeType information...
+  // Merge the NodeType information.
   CurNodeH.getNode()->NodeType |= N->NodeType;
 
   // Start forwarding to the new node!
@@ -666,7 +710,7 @@
 
   // Merge the globals list...
   if (!N->Globals.empty()) {
-    MergeSortedVectors(CurNodeH.getNode()->Globals, N->Globals);
+    CurNodeH.getNode()->mergeGlobals(N->Globals);
 
     // Delete the globals from the old node...
     std::vector<GlobalValue*>().swap(N->Globals);
@@ -679,13 +723,20 @@
 // Offset indicates what offset the specified node is to be merged into the
 // current node.
 //
-// The specified node may be a null pointer (in which case, nothing happens).
+// The specified node may be a null pointer (in which case, we update it to
+// point to this node).
 //
 void DSNode::mergeWith(const DSNodeHandle &NH, unsigned Offset) {
   DSNode *N = NH.getNode();
-  if (N == 0 || (N == this && NH.getOffset() == Offset))
+  if (N == this && NH.getOffset() == Offset)
     return;  // Noop
 
+  // If the RHS is a null node, make it point to this node!
+  if (N == 0) {
+    NH.mergeWith(DSNodeHandle(this, Offset));
+    return;
+  }
+
   assert(!N->isDeadNode() && !isDeadNode());
   assert(!hasNoReferrers() && "Should not try to fold a useless node!");
 
@@ -717,6 +768,232 @@
   DSNode::MergeNodes(CurNodeH, NHCopy);
 }
 
+
+//===----------------------------------------------------------------------===//
+// ReachabilityCloner Implementation
+//===----------------------------------------------------------------------===//
+
+DSNodeHandle ReachabilityCloner::getClonedNH(const DSNodeHandle &SrcNH) {
+  if (SrcNH.isNull()) return DSNodeHandle();
+  const DSNode *SN = SrcNH.getNode();
+
+  DSNodeHandle &NH = NodeMap[SN];
+  if (!NH.isNull())    // Node already mapped?
+    return DSNodeHandle(NH.getNode(), NH.getOffset()+SrcNH.getOffset());
+
+  DSNode *DN = new DSNode(*SN, &Dest, true /* Null out all links */);
+  DN->maskNodeTypes(BitsToKeep);
+  NH = DN;
+  
+  // Next, recursively clone all outgoing links as necessary.  Note that
+  // adding these links can cause the node to collapse itself at any time, and
+  // the current node may be merged with arbitrary other nodes.  For this
+  // reason, we must always go through NH.
+  DN = 0;
+  for (unsigned i = 0, e = SN->getNumLinks(); i != e; ++i) {
+    const DSNodeHandle &SrcEdge = SN->getLink(i << DS::PointerShift);
+    if (!SrcEdge.isNull()) {
+      const DSNodeHandle &DestEdge = getClonedNH(SrcEdge);
+      // Compute the offset into the current node at which to
+      // merge this link.  In the common case, this is a linear
+      // relation to the offset in the original node (with
+      // wrapping), but if the current node gets collapsed due to
+      // recursive merging, we must make sure to merge in all remaining
+      // links at offset zero.
+      unsigned MergeOffset = 0;
+      DSNode *CN = NH.getNode();
+      if (CN->getSize() != 1)
+        MergeOffset = ((i << DS::PointerShift)+NH.getOffset()
+                       - SrcNH.getOffset()) %CN->getSize();
+      CN->addEdgeTo(MergeOffset, DestEdge);
+    }
+  }
+  
+  // If this node contains any globals, make sure they end up in the scalar
+  // map with the correct offset.
+  for (DSNode::global_iterator I = SN->global_begin(), E = SN->global_end();
+       I != E; ++I) {
+    GlobalValue *GV = *I;
+    const DSNodeHandle &SrcGNH = Src.getNodeForValue(GV);
+    DSNodeHandle &DestGNH = NodeMap[SrcGNH.getNode()];
+    assert(DestGNH.getNode() == NH.getNode() &&"Global mapping inconsistent");
+    Dest.getNodeForValue(GV).mergeWith(DSNodeHandle(DestGNH.getNode(),
+                                       DestGNH.getOffset()+SrcGNH.getOffset()));
+    
+    if (CloneFlags & DSGraph::UpdateInlinedGlobals)
+      Dest.getInlinedGlobals().insert(GV);
+  }
+
+  return DSNodeHandle(NH.getNode(), NH.getOffset()+SrcNH.getOffset());
+}
+
+void ReachabilityCloner::merge(const DSNodeHandle &NH,
+                               const DSNodeHandle &SrcNH) {
+  if (SrcNH.isNull()) return;  // Noop
+  if (NH.isNull()) {
+    // If there is no destination node, just clone the source and assign the
+    // destination node to be it.
+    NH.mergeWith(getClonedNH(SrcNH));
+    return;
+  }
+
+  // Okay, at this point, we know that we have both a destination and a source
+  // node that need to be merged.  Check to see if the source node has already
+  // been cloned.
+  const DSNode *SN = SrcNH.getNode();
+  DSNodeHandle &SCNH = NodeMap[SN];  // SourceClonedNodeHandle
+  if (!SCNH.isNull()) {   // Node already cloned?
+    NH.mergeWith(DSNodeHandle(SCNH.getNode(),
+                              SCNH.getOffset()+SrcNH.getOffset()));
+
+    return;  // Nothing to do!
+  }
+
+  // Okay, so the source node has not already been cloned.  Instead of creating
+  // a new DSNode, only to merge it into the one we already have, try to perform
+  // the merge in-place.  The only case we cannot handle here is when the offset
+  // into the existing node is less than the offset into the virtual node we are
+  // merging in.  In this case, we have to extend the existing node, which
+  // requires an allocation anyway.
+  DSNode *DN = NH.getNode();   // Make sure the Offset is up-to-date
+  if (NH.getOffset() >= SrcNH.getOffset()) {
+    if (!DN->isNodeCompletelyFolded()) {
+      // Make sure the destination node is folded if the source node is folded.
+      if (SN->isNodeCompletelyFolded()) {
+        DN->foldNodeCompletely();
+        DN = NH.getNode();
+      } else if (SN->getSize() != DN->getSize()) {
+        // If the two nodes are of different size, and the smaller node has the
+        // array bit set, collapse!
+        if (SN->getSize() < DN->getSize()) {
+          if (SN->isArray()) {
+            DN->foldNodeCompletely();
+            DN = NH.getNode();
+          }
+        } else if (DN->isArray()) {
+          DN->foldNodeCompletely();
+          DN = NH.getNode();
+        }
+      }
+    
+      // Merge the type entries of the two nodes together...    
+      if (SN->getType() != Type::VoidTy && !DN->isNodeCompletelyFolded()) {
+        DN->mergeTypeInfo(SN->getType(), NH.getOffset()-SrcNH.getOffset());
+        DN = NH.getNode();
+      }
+    }
+
+    assert(!DN->isDeadNode());
+    
+    // Merge the NodeType information.
+    DN->mergeNodeFlags(SN->getNodeFlags() & BitsToKeep);
+
+    // Before we start merging outgoing links and updating the scalar map, make
+    // sure it is known that this is the representative node for the src node.
+    SCNH = DSNodeHandle(DN, NH.getOffset()-SrcNH.getOffset());
+
+    // If the source node contains any globals, make sure they end up in the
+    // scalar map with the correct offset.
+    if (SN->global_begin() != SN->global_end()) {
+      // Update the globals in the destination node itself.
+      DN->mergeGlobals(SN->getGlobals());
+
+      // Update the scalar map for the graph we are merging the source node
+      // into.
+      for (DSNode::global_iterator I = SN->global_begin(), E = SN->global_end();
+           I != E; ++I) {
+        GlobalValue *GV = *I;
+        const DSNodeHandle &SrcGNH = Src.getNodeForValue(GV);
+        DSNodeHandle &DestGNH = NodeMap[SrcGNH.getNode()];
+        assert(DestGNH.getNode()==NH.getNode() &&"Global mapping inconsistent");
+        Dest.getNodeForValue(GV).mergeWith(DSNodeHandle(DestGNH.getNode(),
+                                      DestGNH.getOffset()+SrcGNH.getOffset()));
+        
+        if (CloneFlags & DSGraph::UpdateInlinedGlobals)
+          Dest.getInlinedGlobals().insert(GV);
+      }
+    }
+  } else {
+    // We cannot handle this case without allocating a temporary node.  Fall
+    // back on being simple.
+    DSNode *NewDN = new DSNode(*SN, &Dest, true /* Null out all links */);
+    NewDN->maskNodeTypes(BitsToKeep);
+
+    unsigned NHOffset = NH.getOffset();
+    NH.mergeWith(DSNodeHandle(NewDN, SrcNH.getOffset()));
+
+    assert(NH.getNode() &&
+           (NH.getOffset() > NHOffset ||
+            (NH.getOffset() == 0 && NH.getNode()->isNodeCompletelyFolded())) &&
+           "Merging did not adjust the offset!");
+
+    // Before we start merging outgoing links and updating the scalar map, make
+    // sure it is known that this is the representative node for the src node.
+    SCNH = DSNodeHandle(NH.getNode(), NH.getOffset()-SrcNH.getOffset());
+
+    // If the source node contained any globals, make sure to create entries 
+    // in the scalar map for them!
+    for (DSNode::global_iterator I = SN->global_begin(), E = SN->global_end();
+         I != E; ++I) {
+      GlobalValue *GV = *I;
+      const DSNodeHandle &SrcGNH = Src.getNodeForValue(GV);
+      DSNodeHandle &DestGNH = NodeMap[SrcGNH.getNode()];
+      assert(DestGNH.getNode()==NH.getNode() &&"Global mapping inconsistent");
+      assert(SrcGNH.getNode() == SN && "Global mapping inconsistent");
+      Dest.getNodeForValue(GV).mergeWith(DSNodeHandle(DestGNH.getNode(),
+                                    DestGNH.getOffset()+SrcGNH.getOffset()));
+      
+      if (CloneFlags & DSGraph::UpdateInlinedGlobals)
+        Dest.getInlinedGlobals().insert(GV);
+    }
+  }
+
+
+  // Next, recursively merge all outgoing links as necessary.  Note that
+  // adding these links can cause the destination node to collapse itself at
+  // any time, and the current node may be merged with arbitrary other nodes.
+  // For this reason, we must always go through NH.
+  DN = 0;
+  for (unsigned i = 0, e = SN->getNumLinks(); i != e; ++i) {
+    const DSNodeHandle &SrcEdge = SN->getLink(i << DS::PointerShift);
+    if (!SrcEdge.isNull()) {
+      // Compute the offset into the current node at which to
+      // merge this link.  In the common case, this is a linear
+      // relation to the offset in the original node (with
+      // wrapping), but if the current node gets collapsed due to
+      // recursive merging, we must make sure to merge in all remaining
+      // links at offset zero.
+      unsigned MergeOffset = 0;
+      DSNode *CN = SCNH.getNode();
+      if (CN->getSize() != 1)
+        MergeOffset = ((i << DS::PointerShift)+SCNH.getOffset()) %CN->getSize();
+      
+      DSNodeHandle &Link = CN->getLink(MergeOffset);
+      if (!Link.isNull()) {
+        // Perform the recursive merging.  Make sure to create a temporary NH,
+        // because the Link can disappear in the process of recursive merging.
+        DSNodeHandle Tmp = Link;
+        merge(Tmp, SrcEdge);
+      } else {
+        merge(Link, SrcEdge);
+      }
+    }
+  }
+}
+
+/// mergeCallSite - Merge the nodes reachable from the specified src call
+/// site into the nodes reachable from DestCS.
+void ReachabilityCloner::mergeCallSite(const DSCallSite &DestCS,
+                                       const DSCallSite &SrcCS) {
+  merge(DestCS.getRetVal(), SrcCS.getRetVal());
+  unsigned MinArgs = DestCS.getNumPtrArgs();
+  if (SrcCS.getNumPtrArgs() < MinArgs) MinArgs = SrcCS.getNumPtrArgs();
+  
+  for (unsigned a = 0; a != MinArgs; ++a)
+    merge(DestCS.getPtrArg(a), SrcCS.getPtrArg(a));
+}
+
+
 //===----------------------------------------------------------------------===//
 // DSCallSite Implementation
 //===----------------------------------------------------------------------===//
@@ -726,6 +1003,10 @@
   return *Site.getInstruction()->getParent()->getParent();
 }
 
+void DSCallSite::InitNH(DSNodeHandle &NH, const DSNodeHandle &Src,
+                        ReachabilityCloner &RC) {
+  NH = RC.getClonedNH(Src);
+}
 
 //===----------------------------------------------------------------------===//
 // DSGraph Implementation
@@ -752,14 +1033,12 @@
   PrintAuxCalls = false;
   NodeMapTy NodeMap;
   cloneInto(G, ScalarMap, ReturnNodes, NodeMap);
-  InlinedGlobals.clear();               // clear set of "up-to-date" globals
 }
 
 DSGraph::DSGraph(const DSGraph &G, NodeMapTy &NodeMap)
   : GlobalsGraph(0), TD(G.TD) {
   PrintAuxCalls = false;
   cloneInto(G, ScalarMap, ReturnNodes, NodeMap);
-  InlinedGlobals.clear();               // clear set of "up-to-date" globals
 }
 
 DSGraph::~DSGraph() {
@@ -770,11 +1049,11 @@
   ReturnNodes.clear();
 
   // Drop all intra-node references, so that assertions don't fail...
-  std::for_each(Nodes.begin(), Nodes.end(),
-                std::mem_fun(&DSNode::dropAllReferences));
+  for (node_iterator NI = node_begin(), E = node_end(); NI != E; ++NI)
+    (*NI)->dropAllReferences();
 
-  // Delete all of the nodes themselves...
-  std::for_each(Nodes.begin(), Nodes.end(), deleter<DSNode>);
+  // Free all of the nodes.
+  Nodes.clear();
 }
 
 // dump - Allow inspection of graph in a debugger.
@@ -785,132 +1064,36 @@
 /// specified mapping.
 ///
 void DSNode::remapLinks(DSGraph::NodeMapTy &OldNodeMap) {
-  for (unsigned i = 0, e = Links.size(); i != e; ++i) {
-    DSNodeHandle &H = OldNodeMap[Links[i].getNode()];
-    Links[i].setNode(H.getNode());
-    Links[i].setOffset(Links[i].getOffset()+H.getOffset());
-  }
-}
-
-
-/// cloneReachableNodes - Clone all reachable nodes from *Node into the
-/// current graph.  This is a recursive function.  The map OldNodeMap is a
-/// map from the original nodes to their clones.
-/// 
-void DSGraph::cloneReachableNodes(const DSNode*  Node,
-                                  unsigned BitsToClear,
-                                  NodeMapTy& OldNodeMap,
-                                  NodeMapTy& CompletedNodeMap) {
-  if (CompletedNodeMap.find(Node) != CompletedNodeMap.end())
-    return;
-
-  DSNodeHandle& NH = OldNodeMap[Node];
-  if (NH.getNode() != NULL)
-    return;
-
-  // else Node has not yet been cloned: clone it and clear the specified bits
-  NH = new DSNode(*Node, this);          // enters in OldNodeMap
-  NH.getNode()->maskNodeTypes(~BitsToClear);
-
-  // now recursively clone nodes pointed to by this node
-  for (unsigned i = 0, e = Node->getNumLinks(); i != e; ++i) {
-    const DSNodeHandle &Link = Node->getLink(i << DS::PointerShift);
-    if (const DSNode* nextNode = Link.getNode())
-      cloneReachableNodes(nextNode, BitsToClear, OldNodeMap, CompletedNodeMap);
-  }
-}
-
-void DSGraph::cloneReachableSubgraph(const DSGraph& G,
-                                     const hash_set<const DSNode*>& RootNodes,
-                                     NodeMapTy& OldNodeMap,
-                                     NodeMapTy& CompletedNodeMap,
-                                     unsigned CloneFlags) {
-  if (RootNodes.empty())
-    return;
-
-  assert(OldNodeMap.empty() && "Returned OldNodeMap should be empty!");
-  assert(&G != this && "Cannot clone graph into itself!");
-  assert((*RootNodes.begin())->getParentGraph() == &G &&
-         "Root nodes do not belong to this graph!");
-
-  // Remove alloca or mod/ref bits as specified...
-  unsigned BitsToClear = ((CloneFlags & StripAllocaBit)? DSNode::AllocaNode : 0)
-    | ((CloneFlags & StripModRefBits)? (DSNode::Modified | DSNode::Read) : 0)
-    | ((CloneFlags & StripIncompleteBit)? DSNode::Incomplete : 0);
-  BitsToClear |= DSNode::DEAD;  // Clear dead flag...
-
-  // Clone all nodes reachable from each root node, using a recursive helper
-  for (hash_set<const DSNode*>::const_iterator I = RootNodes.begin(),
-         E = RootNodes.end(); I != E; ++I)
-    cloneReachableNodes(*I, BitsToClear, OldNodeMap, CompletedNodeMap);
-
-  // Merge the map entries in OldNodeMap and CompletedNodeMap to remap links
-  NodeMapTy MergedMap(OldNodeMap);
-  MergedMap.insert(CompletedNodeMap.begin(), CompletedNodeMap.end());
-
-  // Rewrite the links in the newly created nodes (the nodes in OldNodeMap)
-  // to point into the current graph.  MergedMap gives the full mapping.
-  for (NodeMapTy::iterator I=OldNodeMap.begin(), E=OldNodeMap.end(); I!= E; ++I)
-    I->second.getNode()->remapLinks(MergedMap);
-
-  // Now merge cloned global nodes with their copies in the current graph
-  // Just look through OldNodeMap to find such nodes!
-  for (NodeMapTy::iterator I=OldNodeMap.begin(), E=OldNodeMap.end(); I!= E; ++I)
-    if (I->first->isGlobalNode()) {
-      DSNodeHandle &GClone = I->second;
-      assert(GClone.getNode() != NULL && "NULL node in OldNodeMap?");
-      const std::vector<GlobalValue*> &Globals = I->first->getGlobals();
-      for (unsigned gi = 0, ge = Globals.size(); gi != ge; ++gi) {
-        DSNodeHandle &GH = ScalarMap[Globals[gi]];
-        GH.mergeWith(GClone);
+  for (unsigned i = 0, e = Links.size(); i != e; ++i)
+    if (DSNode *N = Links[i].getNode()) {
+      DSGraph::NodeMapTy::const_iterator ONMI = OldNodeMap.find(N);
+      if (ONMI != OldNodeMap.end()) {
+        Links[i].setNode(ONMI->second.getNode());
+        Links[i].setOffset(Links[i].getOffset()+ONMI->second.getOffset());
       }
     }
 }
 
-
 /// updateFromGlobalGraph - This function rematerializes global nodes and
 /// nodes reachable from them from the globals graph into the current graph.
-/// It invokes cloneReachableSubgraph, using the globals in the current graph
-/// as the roots.  It also uses the vector InlinedGlobals to avoid cloning and
-/// merging globals that are already up-to-date in the current graph.  In
-/// practice, in the TD pass, this is likely to be a large fraction of the
-/// live global nodes in each function (since most live nodes are likely to
-/// have been brought up-to-date in at _some_ caller or callee).
+/// It uses the vector InlinedGlobals to avoid cloning and merging globals that
+/// are already up-to-date in the current graph.  In practice, in the TD pass,
+/// this is likely to be a large fraction of the live global nodes in each
+/// function (since most live nodes are likely to have been brought up-to-date
+/// in at _some_ caller or callee).
 /// 
 void DSGraph::updateFromGlobalGraph() {
+  TIME_REGION(X, "updateFromGlobalGraph");
+  ReachabilityCloner RC(*this, *GlobalsGraph, 0);
 
-  // Use a map to keep track of the mapping between nodes in the globals graph
-  // and this graph for up-to-date global nodes, which do not need to be cloned.
-  NodeMapTy CompletedMap;
-
-  // Put the live, non-up-to-date global nodes into a set and the up-to-date
-  // ones in the map above, mapping node in GlobalsGraph to the up-to-date node.
-  hash_set<const DSNode*> GlobalNodeSet;
-  for (ScalarMapTy::const_iterator I = getScalarMap().begin(),
-         E = getScalarMap().end(); I != E; ++I)
-    if (GlobalValue* GV = dyn_cast<GlobalValue>(I->first)) {
-      DSNode* GNode = I->second.getNode();
-      assert(GNode && "No node for live global in current Graph?");
-      if (const DSNode* GGNode = GlobalsGraph->ScalarMap[GV].getNode())
-        if (InlinedGlobals.count(GV) == 0) // GNode is not up-to-date
-          GlobalNodeSet.insert(GGNode);
-        else {                                       // GNode is up-to-date 
-          CompletedMap[GGNode] = I->second;
-          assert(GGNode->getNumLinks() == GNode->getNumLinks() &&
-                 "Links dont match in a node that is supposed to be up-to-date?"
-                 "\nremapLinks() will not work if the links don't match!");
-        }
+  // Clone the non-up-to-date global nodes into this graph.
+  for (DSScalarMap::global_iterator I = getScalarMap().global_begin(),
+         E = getScalarMap().global_end(); I != E; ++I)
+    if (InlinedGlobals.count(*I) == 0) { // GNode is not up-to-date
+      DSScalarMap::iterator It = GlobalsGraph->ScalarMap.find(*I);
+      if (It != GlobalsGraph->ScalarMap.end())
+        RC.merge(getNodeForValue(*I), It->second);
     }
-
-  // Clone the subgraph reachable from the vector of nodes in GlobalNodes
-  // and merge the cloned global nodes with the corresponding ones, if any.
-  NodeMapTy OldNodeMap;
-  cloneReachableSubgraph(*GlobalsGraph, GlobalNodeSet, OldNodeMap,CompletedMap);
-
-  // Merging global nodes leaves behind unused nodes: get rid of them now.
-  OldNodeMap.clear();      // remove references before dead node cleanup 
-  CompletedMap.clear();    // remove references before dead node cleanup 
-  removeTriviallyDeadNodes();
 }
 
 /// cloneInto - Clone the specified DSGraph into the current graph.  The
@@ -919,39 +1102,44 @@
 ///
 /// The CloneFlags member controls various aspects of the cloning process.
 ///
-void DSGraph::cloneInto(const DSGraph &G, ScalarMapTy &OldValMap,
+void DSGraph::cloneInto(const DSGraph &G, DSScalarMap &OldValMap,
                         ReturnNodesTy &OldReturnNodes, NodeMapTy &OldNodeMap,
                         unsigned CloneFlags) {
+  TIME_REGION(X, "cloneInto");
   assert(OldNodeMap.empty() && "Returned OldNodeMap should be empty!");
   assert(&G != this && "Cannot clone graph into itself!");
 
-  unsigned FN = Nodes.size();           // First new node...
-
-  // Duplicate all of the nodes, populating the node map...
-  Nodes.reserve(FN+G.Nodes.size());
-
   // Remove alloca or mod/ref bits as specified...
   unsigned BitsToClear = ((CloneFlags & StripAllocaBit)? DSNode::AllocaNode : 0)
     | ((CloneFlags & StripModRefBits)? (DSNode::Modified | DSNode::Read) : 0)
     | ((CloneFlags & StripIncompleteBit)? DSNode::Incomplete : 0);
   BitsToClear |= DSNode::DEAD;  // Clear dead flag...
-  for (unsigned i = 0, e = G.Nodes.size(); i != e; ++i) {
-    DSNode *Old = G.Nodes[i];
-    DSNode *New = new DSNode(*Old, this);
+
+  for (node_iterator I = G.node_begin(), E = G.node_end(); I != E; ++I) {
+    assert(!(*I)->isForwarding() &&
+           "Forward nodes shouldn't be in node list!");
+    DSNode *New = new DSNode(**I, this);
     New->maskNodeTypes(~BitsToClear);
-    OldNodeMap[Old] = New;
+    OldNodeMap[*I] = New;
   }
-
+  
 #ifndef NDEBUG
   Timer::addPeakMemoryMeasurement();
 #endif
-
+  
   // Rewrite the links in the new nodes to point into the current graph now.
-  for (unsigned i = FN, e = Nodes.size(); i != e; ++i)
-    Nodes[i]->remapLinks(OldNodeMap);
+  // Note that we don't loop over the node's list to do this.  The problem is
+  // that remaping links can cause recursive merging to happen, which means
+  // that node_iterator's can get easily invalidated!  Because of this, we
+  // loop over the OldNodeMap, which contains all of the new nodes as the
+  // .second element of the map elements.  Also note that if we remap a node
+  // more than once, we won't break anything.
+  for (NodeMapTy::iterator I = OldNodeMap.begin(), E = OldNodeMap.end();
+       I != E; ++I)
+    I->second.getNode()->remapLinks(OldNodeMap);
 
   // Copy the scalar map... merging all of the global nodes...
-  for (ScalarMapTy::const_iterator I = G.ScalarMap.begin(),
+  for (DSScalarMap::const_iterator I = G.ScalarMap.begin(),
          E = G.ScalarMap.end(); I != E; ++I) {
     DSNodeHandle &MappedNode = OldNodeMap[I->second.getNode()];
     DSNodeHandle &H = OldValMap[I->first];
@@ -961,7 +1149,8 @@
     // If this is a global, add the global to this fn or merge if already exists
     if (GlobalValue* GV = dyn_cast<GlobalValue>(I->first)) {
       ScalarMap[GV].mergeWith(H);
-      InlinedGlobals.insert(GV);
+      if (CloneFlags & DSGraph::UpdateInlinedGlobals)
+        InlinedGlobals.insert(GV);
     }
   }
 
@@ -992,6 +1181,7 @@
   }
 }
 
+
 /// mergeInGraph - The method is used for merging graphs together.  If the
 /// argument graph is not *this, it makes a clone of the specified graph, then
 /// merges the nodes specified in the call site with the formal arguments in the
@@ -999,52 +1189,83 @@
 ///
 void DSGraph::mergeInGraph(const DSCallSite &CS, Function &F,
                            const DSGraph &Graph, unsigned CloneFlags) {
-  ScalarMapTy OldValMap, *ScalarMap;
-  DSNodeHandle RetVal;
+  TIME_REGION(X, "mergeInGraph");
 
   // If this is not a recursive call, clone the graph into this graph...
   if (&Graph != this) {
-    // Clone the callee's graph into the current graph, keeping
-    // track of where scalars in the old graph _used_ to point,
-    // and of the new nodes matching nodes of the old graph.
-    NodeMapTy OldNodeMap;
+    // Clone the callee's graph into the current graph, keeping track of where
+    // scalars in the old graph _used_ to point, and of the new nodes matching
+    // nodes of the old graph.
+    ReachabilityCloner RC(*this, Graph, CloneFlags);
+    
+    // Set up argument bindings
+    Function::aiterator AI = F.abegin();
+    for (unsigned i = 0, e = CS.getNumPtrArgs(); i != e; ++i, ++AI) {
+      // Advance the argument iterator to the first pointer argument...
+      while (AI != F.aend() && !isPointerType(AI->getType())) {
+        ++AI;
+#ifndef NDEBUG  // FIXME: We should merge vararg arguments!
+        if (AI == F.aend() && !F.getFunctionType()->isVarArg())
+          std::cerr << "Bad call to Function: " << F.getName() << "\n";
+#endif
+      }
+      if (AI == F.aend()) break;
+      
+      // Add the link from the argument scalar to the provided value.
+      RC.merge(CS.getPtrArg(i), Graph.getNodeForValue(AI));
+    }
+    
+    // Map the return node pointer over.
+    if (!CS.getRetVal().isNull())
+      RC.merge(CS.getRetVal(), Graph.getReturnNodeFor(F));
+    
+    // If requested, copy the calls or aux-calls lists.
+    if (!(CloneFlags & DontCloneCallNodes)) {
+      // Copy the function calls list...
+      FunctionCalls.reserve(FunctionCalls.size()+Graph.FunctionCalls.size());
+      for (unsigned i = 0, ei = Graph.FunctionCalls.size(); i != ei; ++i)
+        FunctionCalls.push_back(DSCallSite(Graph.FunctionCalls[i], RC));
+    }
+    
+    if (!(CloneFlags & DontCloneAuxCallNodes)) {
+      // Copy the auxiliary function calls list...
+      AuxFunctionCalls.reserve(AuxFunctionCalls.size()+
+                               Graph.AuxFunctionCalls.size());
+      for (unsigned i = 0, ei = Graph.AuxFunctionCalls.size(); i != ei; ++i)
+        AuxFunctionCalls.push_back(DSCallSite(Graph.AuxFunctionCalls[i], RC));
+    }
     
-    // The clone call may invalidate any of the vectors in the data
-    // structure graph.  Strip locals and don't copy the list of callers
-    ReturnNodesTy OldRetNodes;
-    cloneInto(Graph, OldValMap, OldRetNodes, OldNodeMap, CloneFlags);
-
-    // We need to map the arguments for the function to the cloned nodes old
-    // argument values.  Do this now.
-    RetVal = OldRetNodes[&F];
-    ScalarMap = &OldValMap;
+    // Clone over all globals that appear in the caller and callee graphs.
+    for (DSScalarMap::global_iterator GI = Graph.getScalarMap().global_begin(),
+           E = Graph.getScalarMap().global_end(); GI != E; ++GI)
+      if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*GI))
+        if (ScalarMap.count(GV))
+          RC.merge(ScalarMap[GV], Graph.getNodeForValue(GV));
   } else {
-    RetVal = getReturnNodeFor(F);
-    ScalarMap = &getScalarMap();
-  }
-
-  // Merge the return value with the return value of the context...
-  RetVal.mergeWith(CS.getRetVal());
+    DSNodeHandle RetVal = getReturnNodeFor(F);
 
-  // Resolve all of the function arguments...
-  Function::aiterator AI = F.abegin();
-
-  for (unsigned i = 0, e = CS.getNumPtrArgs(); i != e; ++i, ++AI) {
-    // Advance the argument iterator to the first pointer argument...
-    while (AI != F.aend() && !isPointerType(AI->getType())) {
-      ++AI;
-#ifndef NDEBUG
-      if (AI == F.aend())
-        std::cerr << "Bad call to Function: " << F.getName() << "\n";
+    // Merge the return value with the return value of the context...
+    RetVal.mergeWith(CS.getRetVal());
+    
+    // Resolve all of the function arguments...
+    Function::aiterator AI = F.abegin();
+    
+    for (unsigned i = 0, e = CS.getNumPtrArgs(); i != e; ++i, ++AI) {
+      // Advance the argument iterator to the first pointer argument...
+      while (AI != F.aend() && !isPointerType(AI->getType())) {
+        ++AI;
+#ifndef NDEBUG // FIXME: We should merge varargs arguments!!
+        if (AI == F.aend() && !F.getFunctionType()->isVarArg())
+          std::cerr << "Bad call to Function: " << F.getName() << "\n";
 #endif
+      }
+      if (AI == F.aend()) break;
+      
+      // Add the link from the argument scalar to the provided value
+      DSNodeHandle &NH = getNodeForValue(AI);
+      assert(NH.getNode() && "Pointer argument without scalarmap entry?");
+      NH.mergeWith(CS.getPtrArg(i));
     }
-    if (AI == F.aend()) break;
-    
-    // Add the link from the argument scalar to the provided value
-    assert(ScalarMap->count(AI) && "Argument not in scalar map?");
-    DSNodeHandle &NH = (*ScalarMap)[AI];
-    assert(NH.getNode() && "Pointer argument without scalarmap entry?");
-    NH.mergeWith(CS.getPtrArg(i));
   }
 }
 
@@ -1056,7 +1277,7 @@
 
   for (Function::aiterator I = F.abegin(), E = F.aend(); I != E; ++I)
     if (isPointerType(I->getType()))
-      Args.push_back(getScalarMap().find(I)->second);
+      Args.push_back(getNodeForValue(I));
 
   return DSCallSite(CallSite(), getReturnNodeFor(F), &F, Args);
 }
@@ -1109,9 +1330,8 @@
       Function &F = *FI->first;
       if (F.getName() != "main")
         for (Function::aiterator I = F.abegin(), E = F.aend(); I != E; ++I)
-          if (isPointerType(I->getType()) &&
-              ScalarMap.find(I) != ScalarMap.end())
-            markIncompleteNode(ScalarMap[I].getNode());
+          if (isPointerType(I->getType()))
+            markIncompleteNode(getNodeForValue(I).getNode());
     }
 
   // Mark stuff passed into functions calls as being incomplete...
@@ -1125,9 +1345,11 @@
 
   // Mark all global nodes as incomplete...
   if ((Flags & DSGraph::IgnoreGlobals) == 0)
-    for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
-      if (Nodes[i]->isGlobalNode() && Nodes[i]->getNumLinks())
-        markIncompleteNode(Nodes[i]);
+    for (DSScalarMap::global_iterator I = ScalarMap.global_begin(),
+           E = ScalarMap.global_end(); I != E; ++I)
+      if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*I))
+        if (!GV->isConstant())
+          markIncompleteNode(ScalarMap[GV].getNode());
 }
 
 static inline void killIfUselessEdge(DSNodeHandle &Edge) {
@@ -1148,11 +1370,11 @@
 }
 
 static void removeIdenticalCalls(std::vector<DSCallSite> &Calls) {
-
   // Remove trivially identical function calls
   unsigned NumFns = Calls.size();
   std::sort(Calls.begin(), Calls.end());  // Sort by callee as primary key!
 
+#if 1
   // Scan the call list cleaning it up as necessary...
   DSNode   *LastCalleeNode = 0;
   Function *LastCalleeFunc = 0;
@@ -1164,8 +1386,11 @@
     // If the Callee is a useless edge, this must be an unreachable call site,
     // eliminate it.
     if (CS.isIndirectCall() && CS.getCalleeNode()->getNumReferrers() == 1 &&
-        CS.getCalleeNode()->getNodeFlags() == 0) {  // No useful info?
-      std::cerr << "WARNING: Useless call site found??\n";
+        CS.getCalleeNode()->isComplete() &&
+        CS.getCalleeNode()->getGlobals().empty()) {  // No useful info?
+#ifndef NDEBUG
+      std::cerr << "WARNING: Useless call site found.\n";
+#endif
       CS.swap(Calls.back());
       Calls.pop_back();
       --i;
@@ -1193,12 +1418,21 @@
           else
             LastCalleeContainsExternalFunction = LastCalleeFunc->isExternal();
         }
-        
+     
+        // It is not clear why, but enabling this code makes DSA really
+        // sensitive to node forwarding.  Basically, with this enabled, DSA
+        // performs different number of inlinings based on which nodes are
+        // forwarding or not.  This is clearly a problem, so this code is
+        // disabled until this can be resolved.
 #if 1
-        if (LastCalleeContainsExternalFunction ||
+        if (LastCalleeContainsExternalFunction
+#if 0
+            ||
             // This should be more than enough context sensitivity!
             // FIXME: Evaluate how many times this is tripped!
-            NumDuplicateCalls > 20) {
+            NumDuplicateCalls > 20
+#endif
+            ) {
           DSCallSite &OCS = Calls[i-1];
           OCS.mergeWith(CS);
           
@@ -1221,9 +1455,8 @@
       }
     }
   }
-
-  Calls.erase(std::unique(Calls.begin(), Calls.end()),
-              Calls.end());
+#endif
+  Calls.erase(std::unique(Calls.begin(), Calls.end()), Calls.end());
 
   // Track the number of call nodes merged away...
   NumCallNodesMerged += NumFns-Calls.size();
@@ -1239,92 +1472,82 @@
 // we don't have to perform any non-trivial analysis here.
 //
 void DSGraph::removeTriviallyDeadNodes() {
-  removeIdenticalCalls(FunctionCalls);
-  removeIdenticalCalls(AuxFunctionCalls);
+  TIME_REGION(X, "removeTriviallyDeadNodes");
 
   // Loop over all of the nodes in the graph, calling getNode on each field.
   // This will cause all nodes to update their forwarding edges, causing
   // forwarded nodes to be delete-able.
-  for (unsigned i = 0, e = Nodes.size(); i != e; ++i) {
-    DSNode *N = Nodes[i];
+  for (node_iterator NI = node_begin(), E = node_end(); NI != E; ++NI) {
+    DSNode *N = *NI;
     for (unsigned l = 0, e = N->getNumLinks(); l != e; ++l)
       N->getLink(l*N->getPointerSize()).getNode();
   }
 
-  // Likewise, forward any edges from the scalar nodes...
-  for (ScalarMapTy::iterator I = ScalarMap.begin(), E = ScalarMap.end();
-       I != E; ++I)
+  // NOTE: This code is disabled.  Though it should, in theory, allow us to
+  // remove more nodes down below, the scan of the scalar map is incredibly
+  // expensive for certain programs (with large SCCs).  In the future, if we can
+  // make the scalar map scan more efficient, then we can reenable this.
+#if 0
+  { TIME_REGION(X, "removeTriviallyDeadNodes:scalarmap");
+
+  // Likewise, forward any edges from the scalar nodes.  While we are at it,
+  // clean house a bit.
+  for (DSScalarMap::iterator I = ScalarMap.begin(),E = ScalarMap.end();I != E;){
     I->second.getNode();
-
+    ++I;
+  }
+  }
+#endif
   bool isGlobalsGraph = !GlobalsGraph;
 
-  for (unsigned i = 0; i != Nodes.size(); ++i) {
-    DSNode *Node = Nodes[i];
+  for (NodeListTy::iterator NI = Nodes.begin(), E = Nodes.end(); NI != E; ) {
+    DSNode &Node = *NI;
 
     // Do not remove *any* global nodes in the globals graph.
     // This is a special case because such nodes may not have I, M, R flags set.
-    if (Node->isGlobalNode() && isGlobalsGraph)
+    if (Node.isGlobalNode() && isGlobalsGraph) {
+      ++NI;
       continue;
+    }
 
-    if (Node->isComplete() && !Node->isModified() && !Node->isRead()) {
+    if (Node.isComplete() && !Node.isModified() && !Node.isRead()) {
       // This is a useless node if it has no mod/ref info (checked above),
       // outgoing edges (which it cannot, as it is not modified in this
       // context), and it has no incoming edges.  If it is a global node it may
       // have all of these properties and still have incoming edges, due to the
       // scalar map, so we check those now.
       //
-      if (Node->getNumReferrers() == Node->getGlobals().size()) {
-        const std::vector<GlobalValue*> &Globals = Node->getGlobals();
+      if (Node.getNumReferrers() == Node.getGlobals().size()) {
+        const std::vector<GlobalValue*> &Globals = Node.getGlobals();
 
         // Loop through and make sure all of the globals are referring directly
         // to the node...
         for (unsigned j = 0, e = Globals.size(); j != e; ++j) {
-          DSNode *N = ScalarMap.find(Globals[j])->second.getNode();
-          assert(N == Node && "ScalarMap doesn't match globals list!");
+          DSNode *N = getNodeForValue(Globals[j]).getNode();
+          assert(N == &Node && "ScalarMap doesn't match globals list!");
         }
 
         // Make sure NumReferrers still agrees, if so, the node is truly dead.
-        if (Node->getNumReferrers() == Globals.size()) {
+        if (Node.getNumReferrers() == Globals.size()) {
           for (unsigned j = 0, e = Globals.size(); j != e; ++j)
             ScalarMap.erase(Globals[j]);
-          Node->makeNodeDead();
+          Node.makeNodeDead();
+          ++NumTrivialGlobalDNE;
         }
       }
-
-#ifdef SANER_CODE_FOR_CHECKING_IF_ALL_REFERRERS_ARE_FROM_SCALARMAP
-      //
-      // *** It seems to me that we should be able to simply check if 
-      // *** there are fewer or equal #referrers as #globals and make
-      // *** sure that all those referrers are in the scalar map?
-      // 
-      if (Node->getNumReferrers() <= Node->getGlobals().size()) {
-        const std::vector<GlobalValue*> &Globals = Node->getGlobals();
-
-#ifndef NDEBUG
-        // Loop through and make sure all of the globals are referring directly
-        // to the node...
-        for (unsigned j = 0, e = Globals.size(); j != e; ++j) {
-          DSNode *N = ScalarMap.find(Globals[j])->second.getNode();
-          assert(N == Node && "ScalarMap doesn't match globals list!");
-        }
-#endif
-
-        // Make sure NumReferrers still agrees.  The node is truly dead.
-        assert(Node->getNumReferrers() == Globals.size());
-        for (unsigned j = 0, e = Globals.size(); j != e; ++j)
-          ScalarMap.erase(Globals[j]);
-        Node->makeNodeDead();
-      }
-#endif
     }
 
-    if (Node->getNodeFlags() == 0 && Node->hasNoReferrers()) {
+    if (Node.getNodeFlags() == 0 && Node.hasNoReferrers()) {
       // This node is dead!
-      delete Node;                        // Free memory...
-      Nodes[i--] = Nodes.back();
-      Nodes.pop_back();                   // Remove from node list...
+      NI = Nodes.erase(NI);    // Erase & remove from node list.
+      ++NumTrivialDNE;
+    } else {
+      ++NI;
     }
   }
+
+  removeIdenticalCalls(FunctionCalls);
+  removeIdenticalCalls(AuxFunctionCalls);
 }
 
 
@@ -1335,11 +1558,9 @@
 void DSNode::markReachableNodes(hash_set<DSNode*> &ReachableNodes) {
   if (this == 0) return;
   assert(getForwardNode() == 0 && "Cannot mark a forwarded node!");
-  if (ReachableNodes.count(this)) return;          // Already marked reachable
-  ReachableNodes.insert(this);                     // Is reachable now
-
-  for (unsigned i = 0, e = getSize(); i < e; i += DS::PointerSize)
-    getLink(i).getNode()->markReachableNodes(ReachableNodes);
+  if (ReachableNodes.insert(this).second)        // Is newly reachable?
+    for (unsigned i = 0, e = getSize(); i < e; i += DS::PointerSize)
+      getLink(i).getNode()->markReachableNodes(ReachableNodes);
 }
 
 void DSCallSite::markReachableNodes(hash_set<DSNode*> &Nodes) {
@@ -1414,20 +1635,45 @@
   // merging...
   removeTriviallyDeadNodes();
 
+  TIME_REGION(X, "removeDeadNodes");
+
   // FIXME: Merge non-trivially identical call nodes...
 
   // Alive - a set that holds all nodes found to be reachable/alive.
   hash_set<DSNode*> Alive;
   std::vector<std::pair<Value*, DSNode*> > GlobalNodes;
 
+  // Copy and merge all information about globals to the GlobalsGraph if this is
+  // not a final pass (where unreachable globals are removed).
+  //
+  // Strip all alloca bits since the current function is only for the BU pass.
+  // Strip all incomplete bits since they are short-lived properties and they
+  // will be correctly computed when rematerializing nodes into the functions.
+  //
+  ReachabilityCloner GGCloner(*GlobalsGraph, *this, DSGraph::StripAllocaBit |
+                              DSGraph::StripIncompleteBit);
+
   // Mark all nodes reachable by (non-global) scalar nodes as alive...
-  for (ScalarMapTy::iterator I = ScalarMap.begin(), E = ScalarMap.end(); I !=E;)
+  { TIME_REGION(Y, "removeDeadNodes:scalarscan");
+  for (DSScalarMap::iterator I = ScalarMap.begin(), E = ScalarMap.end(); I !=E;)
     if (isa<GlobalValue>(I->first)) {             // Keep track of global nodes
       assert(I->second.getNode() && "Null global node?");
       assert(I->second.getNode()->isGlobalNode() && "Should be a global node!");
       GlobalNodes.push_back(std::make_pair(I->first, I->second.getNode()));
+
+      // Make sure that all globals are cloned over as roots.
+      if (!(Flags & DSGraph::RemoveUnreachableGlobals)) {
+        DSGraph::ScalarMapTy::iterator SMI = 
+          GlobalsGraph->getScalarMap().find(I->first);
+        if (SMI != GlobalsGraph->getScalarMap().end())
+          GGCloner.merge(SMI->second, I->second);
+        else
+          GGCloner.getClonedNH(I->second);
+      }
       ++I;
     } else {
+      DSNode *N = I->second.getNode();
+#if 0
       // Check to see if this is a worthless node generated for non-pointer
       // values, such as integers.  Consider an addition of long types: A+B.
       // Assuming we can track all uses of the value in this context, and it is
@@ -1438,16 +1684,17 @@
       // uninteresting for data structure analysis.  If we run across one of
       // these, prune the scalar pointing to it.
       //
-      DSNode *N = I->second.getNode();
-      if (N->getNodeFlags() == DSNode::UnknownNode && !isa<Argument>(I->first)){
+      if (N->getNodeFlags() == DSNode::UnknownNode && !isa<Argument>(I->first))
         ScalarMap.erase(I++);
-      } else {
-        I->second.getNode()->markReachableNodes(Alive);
+      else {
+#endif
+        N->markReachableNodes(Alive);
         ++I;
-      }
+      //}
     }
+  }
 
-  // The return value is alive as well...
+  // The return values are alive as well.
   for (ReturnNodesTy::iterator I = ReturnNodes.begin(), E = ReturnNodes.end();
        I != E; ++I)
     I->second.getNode()->markReachableNodes(Alive);
@@ -1456,14 +1703,6 @@
   for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i)
     FunctionCalls[i].markReachableNodes(Alive);
 
-  // Copy and merge all information about globals to the GlobalsGraph
-  // if this is not a final pass (where unreachable globals are removed)
-  NodeMapTy GlobalNodeMap;
-  hash_set<const DSNode*> GlobalNodeSet;
-
-  for (std::vector<std::pair<Value*, DSNode*> >::const_iterator
-         I = GlobalNodes.begin(), E = GlobalNodes.end(); I != E; ++I)
-    GlobalNodeSet.insert(I->second);    // put global nodes into a set
 
   // Now find globals and aux call nodes that are already live or reach a live
   // value (which makes them live in turn), and continue till no more are found.
@@ -1479,13 +1718,13 @@
     //
     Iterate = false;
     if (!(Flags & DSGraph::RemoveUnreachableGlobals))
-       for (unsigned i = 0; i != GlobalNodes.size(); ++i)
-         if (CanReachAliveNodes(GlobalNodes[i].second, Alive, Visited, 
-                                Flags & DSGraph::RemoveUnreachableGlobals)) {
-           std::swap(GlobalNodes[i--], GlobalNodes.back()); // Move to end to...
-           GlobalNodes.pop_back();                          // erase efficiently
-           Iterate = true;
-         }
+      for (unsigned i = 0; i != GlobalNodes.size(); ++i)
+        if (CanReachAliveNodes(GlobalNodes[i].second, Alive, Visited, 
+                               Flags & DSGraph::RemoveUnreachableGlobals)) {
+          std::swap(GlobalNodes[i--], GlobalNodes.back()); // Move to end to...
+          GlobalNodes.pop_back();                          // erase efficiently
+          Iterate = true;
+        }
 
     // Mark only unresolvable call nodes for moving to the GlobalsGraph since
     // call nodes that get resolved will be difficult to remove from that graph.
@@ -1512,51 +1751,18 @@
   // GlobalsGraph, and all nodes reachable from those nodes
   // 
   if (!(Flags & DSGraph::RemoveUnreachableGlobals)) {
-
-    // First, add the dead aux call nodes to the set of root nodes for cloning
-    // -- return value at this call site, if any
-    // -- actual arguments passed at this call site
-    // -- callee node at this call site, if this is an indirect call
-    for (unsigned i = CurIdx, e = AuxFunctionCalls.size(); i != e; ++i) {
-      if (const DSNode* RetNode = AuxFunctionCalls[i].getRetVal().getNode())
-        GlobalNodeSet.insert(RetNode);
-      for (unsigned j=0, N=AuxFunctionCalls[i].getNumPtrArgs(); j < N; ++j)
-        if (const DSNode* ArgTarget=AuxFunctionCalls[i].getPtrArg(j).getNode())
-          GlobalNodeSet.insert(ArgTarget);
-      if (AuxFunctionCalls[i].isIndirectCall())
-        GlobalNodeSet.insert(AuxFunctionCalls[i].getCalleeNode());
-    }
-    
-    // There are no "pre-completed" nodes so use any empty map for those.
-    // Strip all alloca bits since the current function is only for the BU pass.
-    // Strip all incomplete bits since they are short-lived properties and they
-    // will be correctly computed when rematerializing nodes into the functions.
-    // 
-    NodeMapTy CompletedMap;
-    GlobalsGraph->cloneReachableSubgraph(*this, GlobalNodeSet,
-                                         GlobalNodeMap, CompletedMap,
-                                         (DSGraph::StripAllocaBit |
-                                          DSGraph::StripIncompleteBit));
-  }
-
-  // Remove all dead aux function calls...
-  if (!(Flags & DSGraph::RemoveUnreachableGlobals)) {
-    assert(GlobalsGraph && "No globals graph available??");
-
-    // Copy the unreachable call nodes to the globals graph, updating
-    // their target pointers using the GlobalNodeMap
+    // Copy the unreachable call nodes to the globals graph, updating their
+    // target pointers using the GGCloner
     for (unsigned i = CurIdx, e = AuxFunctionCalls.size(); i != e; ++i)
       GlobalsGraph->AuxFunctionCalls.push_back(DSCallSite(AuxFunctionCalls[i],
-                                                          GlobalNodeMap));
+                                                          GGCloner));
   }
   // Crop all the useless ones out...
   AuxFunctionCalls.erase(AuxFunctionCalls.begin()+CurIdx,
                          AuxFunctionCalls.end());
 
-  // We are finally done with the GlobalNodeMap so we can clear it and
-  // then get rid of unused nodes in the GlobalsGraph produced by merging.
-  GlobalNodeMap.clear();
-  GlobalsGraph->removeTriviallyDeadNodes();
+  // We are finally done with the GGCloner so we can destroy it.
+  GGCloner.destroy();
 
   // At this point, any nodes which are visited, but not alive, are nodes
   // which can be removed.  Loop over all nodes, eliminating completely
@@ -1564,26 +1770,27 @@
   //
   std::vector<DSNode*> DeadNodes;
   DeadNodes.reserve(Nodes.size());
-  for (unsigned i = 0; i != Nodes.size(); ++i)
-    if (!Alive.count(Nodes[i])) {
-      DSNode *N = Nodes[i];
-      Nodes[i--] = Nodes.back();            // move node to end of vector
-      Nodes.pop_back();                     // Erase node from alive list.
+  for (NodeListTy::iterator NI = Nodes.begin(), E = Nodes.end(); NI != E;) {
+    DSNode *N = NI++;
+    assert(!N->isForwarding() && "Forwarded node in nodes list?");
+
+    if (!Alive.count(N)) {
+      Nodes.remove(N);
+      assert(!N->isForwarding() && "Cannot remove a forwarding node!");
       DeadNodes.push_back(N);
       N->dropAllReferences();
-    } else {
-      assert(Nodes[i]->getForwardNode() == 0 && "Alive forwarded node?");
+      ++NumDNE;
     }
+  }
 
   // Remove all unreachable globals from the ScalarMap.
   // If flag RemoveUnreachableGlobals is set, GlobalNodes has only dead nodes.
   // In either case, the dead nodes will not be in the set Alive.
-  for (unsigned i = 0, e = GlobalNodes.size(); i != e; ++i) {
-    assert(((Flags & DSGraph::RemoveUnreachableGlobals) ||
-            !Alive.count(GlobalNodes[i].second)) && "huh? non-dead global");
+  for (unsigned i = 0, e = GlobalNodes.size(); i != e; ++i)
     if (!Alive.count(GlobalNodes[i].second))
       ScalarMap.erase(GlobalNodes[i].first);
-  }
+    else
+      assert((Flags & DSGraph::RemoveUnreachableGlobals) && "non-dead global");
 
   // Delete all dead nodes now since their referrer counts are zero.
   for (unsigned i = 0, e = DeadNodes.size(); i != e; ++i)
@@ -1593,8 +1800,8 @@
 }
 
 void DSGraph::AssertGraphOK() const {
-  for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
-    Nodes[i]->assertOK();
+  for (node_iterator NI = node_begin(), E = node_end(); NI != E; ++NI)
+    (*NI)->assertOK();
 
   for (ScalarMapTy::const_iterator I = ScalarMap.begin(),
          E = ScalarMap.end(); I != E; ++I) {
@@ -1609,36 +1816,6 @@
   AssertCallNodesInGraph();
   AssertAuxCallNodesInGraph();
 }
-
-/// mergeInGlobalsGraph - This method is useful for clients to incorporate the
-/// globals graph into the DS, BU or TD graph for a function.  This code retains
-/// all globals, i.e., does not delete unreachable globals after they are
-/// inlined.
-///
-void DSGraph::mergeInGlobalsGraph() {
-  NodeMapTy GlobalNodeMap;
-  ScalarMapTy OldValMap;
-  ReturnNodesTy OldRetNodes;
-  cloneInto(*GlobalsGraph, OldValMap, OldRetNodes, GlobalNodeMap,
-            DSGraph::KeepAllocaBit | DSGraph::DontCloneCallNodes |
-            DSGraph::DontCloneAuxCallNodes);
-  
-  // Now merge existing global nodes in the GlobalsGraph with their copies
-  for (ScalarMapTy::iterator I = ScalarMap.begin(), E = ScalarMap.end(); 
-       I != E; ++I)
-    if (isa<GlobalValue>(I->first)) {             // Found a global node
-      DSNodeHandle &GH = I->second;
-      DSNodeHandle &GGNodeH = GlobalsGraph->getScalarMap()[I->first];
-      GH.mergeWith(GlobalNodeMap[GGNodeH.getNode()]);
-    }
-  
-  // Merging leaves behind unused nodes: get rid of them now.
-  GlobalNodeMap.clear();
-  OldValMap.clear();
-  OldRetNodes.clear();
-  removeTriviallyDeadNodes();
-}
-
 
 /// computeNodeMapping - Given roots in two different DSGraphs, traverse the
 /// nodes reachable from the two graphs, computing the mapping of nodes from


Index: llvm/lib/Analysis/DataStructure/DataStructureAA.cpp
diff -u llvm/lib/Analysis/DataStructure/DataStructureAA.cpp:1.13 llvm/lib/Analysis/DataStructure/DataStructureAA.cpp:1.13.4.1
--- llvm/lib/Analysis/DataStructure/DataStructureAA.cpp:1.13	Wed Nov 12 17:11:14 2003
+++ llvm/lib/Analysis/DataStructure/DataStructureAA.cpp	Mon Mar  1 17:58:12 2004
@@ -53,6 +53,10 @@
 
     void getMustAliases(Value *P, std::vector<Value*> &RetVals);
 
+    bool pointsToConstantMemory(const Value *P) {
+      return getAnalysis<AliasAnalysis>().pointsToConstantMemory(P);
+    }
+
   private:
     DSGraph *getGraphForValue(const Value *V);
   };
@@ -166,9 +170,8 @@
     
     // The only must alias information we can currently determine occurs when
     // the node for P is a global node with only one entry.
-    const DSGraph::ScalarMapTy &GSM = G->getScalarMap();
-    DSGraph::ScalarMapTy::const_iterator I = GSM.find(P);
-    if (I != GSM.end()) {
+    DSGraph::ScalarMapTy::const_iterator I = G->getScalarMap().find(P);
+    if (I != G->getScalarMap().end()) {
       DSNode *N = I->second.getNode();
       if (N->isComplete() && isSinglePhysicalObject(N))
         RetVals.push_back(N->getGlobals()[0]);


Index: llvm/lib/Analysis/DataStructure/GraphChecker.cpp
diff -u llvm/lib/Analysis/DataStructure/GraphChecker.cpp:1.10 llvm/lib/Analysis/DataStructure/GraphChecker.cpp:1.10.4.1
--- llvm/lib/Analysis/DataStructure/GraphChecker.cpp:1.10	Wed Nov 12 17:11:14 2003
+++ llvm/lib/Analysis/DataStructure/GraphChecker.cpp	Mon Mar  1 17:58:12 2004
@@ -12,7 +12,7 @@
 // or not a node is collapsed, etc.  These are the command line arguments that
 // it supports:
 //
-//   --dsgc-dsapass={local,bu,td}     - Specify what flavor of graph to check
+//   --dsgc-dspass={local,bu,td}      - Specify what flavor of graph to check
 //   --dsgc-abort-if-any-collapsed    - Abort if any collapsed nodes are found
 //   --dsgc-abort-if-collapsed=<list> - Abort if a node pointed to by an SSA
 //                                      value with name in <list> is collapsed
@@ -114,11 +114,10 @@
 void DSGC::verify(const DSGraph &G) {
   // Loop over all of the nodes, checking to see if any are collapsed...
   if (AbortIfAnyCollapsed) {
-    const std::vector<DSNode*> &Nodes = G.getNodes();
-    for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
-      if (Nodes[i]->isNodeCompletelyFolded()) {
+    for (DSGraph::node_iterator I = G.node_begin(), E = G.node_end(); I!=E; ++I)
+      if ((*I)->isNodeCompletelyFolded()) {
         std::cerr << "Node is collapsed: ";
-        Nodes[i]->print(std::cerr, &G);
+        (*I)->print(std::cerr, &G);
         abort();
       }
   }


Index: llvm/lib/Analysis/DataStructure/Local.cpp
diff -u llvm/lib/Analysis/DataStructure/Local.cpp:1.74 llvm/lib/Analysis/DataStructure/Local.cpp:1.74.4.1
--- llvm/lib/Analysis/DataStructure/Local.cpp:1.74	Tue Nov 25 14:19:55 2003
+++ llvm/lib/Analysis/DataStructure/Local.cpp	Mon Mar  1 17:58:12 2004
@@ -17,6 +17,7 @@
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Instructions.h"
+#include "llvm/Intrinsics.h"
 #include "llvm/Support/GetElementPtrTypeIterator.h"
 #include "llvm/Support/InstVisitor.h"
 #include "llvm/Target/TargetData.h"
@@ -37,7 +38,6 @@
 static cl::opt<bool>
 TrackIntegersAsPointers("dsa-track-integers",
          cl::desc("If this is set, track integers as potential pointers"));
-                        
 
 namespace llvm {
 namespace DS {
@@ -72,7 +72,7 @@
   class GraphBuilder : InstVisitor<GraphBuilder> {
     DSGraph &G;
     DSNodeHandle *RetNode;               // Node that gets returned...
-    DSGraph::ScalarMapTy &ScalarMap;
+    DSScalarMap &ScalarMap;
     std::vector<DSCallSite> *FunctionCalls;
 
   public:
@@ -171,13 +171,24 @@
 #endif
 
   // Remove all integral constants from the scalarmap!
-  for (ScalarMapTy::iterator I = ScalarMap.begin(); I != ScalarMap.end();)
-    if (isa<ConstantIntegral>(I->first)) {
-      ScalarMapTy::iterator J = I++;
-      ScalarMap.erase(J);
-    } else
+  for (DSScalarMap::iterator I = ScalarMap.begin(); I != ScalarMap.end();)
+    if (isa<ConstantIntegral>(I->first))
+      ScalarMap.erase(I++);
+    else
       ++I;
 
+  // If there are any constant globals referenced in this function, merge their
+  // initializers into the local graph from the globals graph.
+  if (ScalarMap.global_begin() != ScalarMap.global_end()) {
+    ReachabilityCloner RC(*this, *GG, 0);
+    
+    for (DSScalarMap::global_iterator I = ScalarMap.global_begin();
+         I != ScalarMap.global_end(); ++I)
+      if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*I))
+        if (GV->isConstant())
+          RC.merge(ScalarMap[GV], GG->ScalarMap[GV]);
+  }
+
   markIncompleteNodes(DSGraph::MarkFormalArgs);
 
   // Remove any nodes made dead due to merging...
@@ -211,7 +222,7 @@
         NH = getValueDest(*CE->getOperand(0));
       else if (CE->getOpcode() == Instruction::GetElementPtr) {
         visitGetElementPtrInst(*CE);
-        DSGraph::ScalarMapTy::iterator I = ScalarMap.find(CE);
+        DSScalarMap::iterator I = ScalarMap.find(CE);
         assert(I != ScalarMap.end() && "GEP didn't get processed right?");
         NH = I->second;
       } else {
@@ -372,6 +383,10 @@
     if (const StructType *STy = dyn_cast<StructType>(*I)) {
       unsigned FieldNo = cast<ConstantUInt>(I.getOperand())->getValue();
       Offset += TD.getStructLayout(STy)->MemberOffsets[FieldNo];
+    } else if (const PointerType *PTy = dyn_cast<PointerType>(*I)) {
+      if (!isa<Constant>(I.getOperand()) ||
+          !cast<Constant>(I.getOperand())->isNullValue())
+        Value.getNode()->setArrayMarker();
     }
 
 
@@ -454,42 +469,351 @@
 }
 
 void GraphBuilder::visitCallSite(CallSite CS) {
+  Value *Callee = CS.getCalledValue();
+  if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(Callee))
+    Callee = CPR->getValue();
+
   // Special case handling of certain libc allocation functions here.
-  if (Function *F = CS.getCalledFunction())
+  if (Function *F = dyn_cast<Function>(Callee))
     if (F->isExternal())
-      if (F->getName() == "calloc") {
-        setDestTo(*CS.getInstruction(),
-                  createNode()->setHeapNodeMarker()->setModifiedMarker());
-        return;
-      } else if (F->getName() == "realloc") {
-        DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
-        RetNH.mergeWith(getValueDest(**CS.arg_begin()));
-        if (DSNode *N = RetNH.getNode())
-          N->setHeapNodeMarker()->setModifiedMarker()->setReadMarker();
-        return;
-      } else if (F->getName() == "memset") {
-        // Merge the first argument with the return value, and mark the memory
+      switch (F->getIntrinsicID()) {
+      case Intrinsic::memmove:
+      case Intrinsic::memcpy: {
+        // Merge the first & second arguments, and mark the memory read and
         // modified.
-        DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
-        RetNH.mergeWith(getValueDest(**CS.arg_begin()));
-        if (DSNode *N = RetNH.getNode())
-          N->setModifiedMarker();
-        return;
-      } else if (F->getName() == "memmove") {
-        // Merge the first & second arguments with the result, and mark the
-        // memory read and modified.
-        DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
-        RetNH.mergeWith(getValueDest(**CS.arg_begin()));
+        DSNodeHandle RetNH = getValueDest(**CS.arg_begin());
         RetNH.mergeWith(getValueDest(**(CS.arg_begin()+1)));
         if (DSNode *N = RetNH.getNode())
           N->setModifiedMarker()->setReadMarker();
         return;
-      } else if (F->getName() == "bzero") {
+      }
+      case Intrinsic::memset:
         // Mark the memory modified.
-        DSNodeHandle H = getValueDest(**CS.arg_begin());
-        if (DSNode *N = H.getNode())
+        if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
           N->setModifiedMarker();
         return;
+      default:
+        if (F->getName() == "calloc") {
+          setDestTo(*CS.getInstruction(),
+                    createNode()->setHeapNodeMarker()->setModifiedMarker());
+          return;
+        } else if (F->getName() == "realloc") {
+          DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
+          RetNH.mergeWith(getValueDest(**CS.arg_begin()));
+          if (DSNode *N = RetNH.getNode())
+            N->setHeapNodeMarker()->setModifiedMarker()->setReadMarker();
+          return;
+        } else if (F->getName() == "memmove") {
+          // Merge the first & second arguments, and mark the memory read and
+          // modified.
+          DSNodeHandle RetNH = getValueDest(**CS.arg_begin());
+          RetNH.mergeWith(getValueDest(**(CS.arg_begin()+1)));
+          if (DSNode *N = RetNH.getNode())
+            N->setModifiedMarker()->setReadMarker();
+          return;
+
+        } else if (F->getName() == "atoi" || F->getName() == "atof" ||
+                   F->getName() == "atol" || F->getName() == "atoll" ||
+                   F->getName() == "remove" || F->getName() == "unlink" ||
+                   F->getName() == "rename" || F->getName() == "memcmp" ||
+                   F->getName() == "strcmp" || F->getName() == "strncmp" ||
+                   F->getName() == "execl" || F->getName() == "execlp" ||
+                   F->getName() == "execle" || F->getName() == "execv" ||
+                   F->getName() == "execvp" || F->getName() == "chmod" ||
+                   F->getName() == "puts" || F->getName() == "write" ||
+                   F->getName() == "open" || F->getName() == "create" ||
+                   F->getName() == "truncate" || F->getName() == "chdir" ||
+                   F->getName() == "mkdir" || F->getName() == "rmdir") {
+          // These functions read all of their pointer operands.
+          for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+               AI != E; ++AI) {
+            if (isPointerType((*AI)->getType()))
+              if (DSNode *N = getValueDest(**AI).getNode())
+                N->setReadMarker();   
+          }
+          return;
+        } else if (F->getName() == "read" || F->getName() == "pipe" ||
+                   F->getName() == "wait" || F->getName() == "time") {
+          // These functions write all of their pointer operands.
+          for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+               AI != E; ++AI) {
+            if (isPointerType((*AI)->getType()))
+              if (DSNode *N = getValueDest(**AI).getNode())
+                N->setModifiedMarker();   
+          }
+          return;
+        } else if (F->getName() == "stat" || F->getName() == "fstat" ||
+                   F->getName() == "lstat") {
+          // These functions read their first operand if its a pointer.
+          CallSite::arg_iterator AI = CS.arg_begin();
+          if (isPointerType((*AI)->getType())) {
+            DSNodeHandle Path = getValueDest(**AI);
+            if (DSNode *N = Path.getNode()) N->setReadMarker();
+          }
+
+          // Then they write into the stat buffer.
+          DSNodeHandle StatBuf = getValueDest(**++AI);
+          if (DSNode *N = StatBuf.getNode()) {
+            N->setModifiedMarker();
+            const Type *StatTy = F->getFunctionType()->getParamType(1);
+            if (const PointerType *PTy = dyn_cast<PointerType>(StatTy))
+              N->mergeTypeInfo(PTy->getElementType(), StatBuf.getOffset());
+          }
+          return;
+        } else if (F->getName() == "fopen" || F->getName() == "fdopen" ||
+                   F->getName() == "freopen") {
+          // These functions read all of their pointer operands.
+          for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+               AI != E; ++AI)
+            if (isPointerType((*AI)->getType()))
+              if (DSNode *N = getValueDest(**AI).getNode())
+                N->setReadMarker();
+          
+          // fopen allocates in an unknown way and writes to the file
+          // descriptor.  Also, merge the allocated type into the node.
+          DSNodeHandle Result = getValueDest(*CS.getInstruction());
+          if (DSNode *N = Result.getNode()) {
+            N->setModifiedMarker()->setUnknownNodeMarker();
+            const Type *RetTy = F->getFunctionType()->getReturnType();
+            if (const PointerType *PTy = dyn_cast<PointerType>(RetTy))
+              N->mergeTypeInfo(PTy->getElementType(), Result.getOffset());
+          }
+
+          // If this is freopen, merge the file descriptor passed in with the
+          // result.
+          Result.mergeWith(getValueDest(**--CS.arg_end()));
+
+          return;
+        } else if (F->getName() == "fclose" && CS.arg_end()-CS.arg_begin() ==1){
+          // fclose reads and deallocates the memory in an unknown way for the
+          // file descriptor.  It merges the FILE type into the descriptor.
+          DSNodeHandle H = getValueDest(**CS.arg_begin());
+          if (DSNode *N = H.getNode()) {
+            N->setReadMarker()->setUnknownNodeMarker();
+            const Type *ArgTy = F->getFunctionType()->getParamType(0);
+            if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+              N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+          }
+          return;
+        } else if (CS.arg_end()-CS.arg_begin() == 1 && 
+                   (F->getName() == "fflush" || F->getName() == "feof" ||
+                    F->getName() == "fileno" || F->getName() == "clearerr" ||
+                    F->getName() == "rewind" || F->getName() == "ftell" ||
+                    F->getName() == "ferror" || F->getName() == "fgetc" ||
+                    F->getName() == "fgetc" || F->getName() == "_IO_getc")) {
+          // fflush reads and writes the memory for the file descriptor.  It
+          // merges the FILE type into the descriptor.
+          DSNodeHandle H = getValueDest(**CS.arg_begin());
+          if (DSNode *N = H.getNode()) {
+            N->setReadMarker()->setModifiedMarker();
+          
+            const Type *ArgTy = F->getFunctionType()->getParamType(0);
+            if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+              N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+          }
+          return;
+        } else if (CS.arg_end()-CS.arg_begin() == 4 && 
+                   (F->getName() == "fwrite" || F->getName() == "fread")) {
+          // fread writes the first operand, fwrite reads it.  They both
+          // read/write the FILE descriptor, and merges the FILE type.
+          DSNodeHandle H = getValueDest(**--CS.arg_end());
+          if (DSNode *N = H.getNode()) {
+            N->setReadMarker()->setModifiedMarker();
+            const Type *ArgTy = F->getFunctionType()->getParamType(3);
+            if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+              N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+          }
+
+          H = getValueDest(**CS.arg_begin());
+          if (DSNode *N = H.getNode())
+            if (F->getName() == "fwrite")
+              N->setReadMarker();
+            else
+              N->setModifiedMarker();
+          return;
+        } else if (F->getName() == "fgets" && CS.arg_end()-CS.arg_begin() == 3){
+          // fgets reads and writes the memory for the file descriptor.  It
+          // merges the FILE type into the descriptor, and writes to the
+          // argument.  It returns the argument as well.
+          CallSite::arg_iterator AI = CS.arg_begin();
+          DSNodeHandle H = getValueDest(**AI);
+          if (DSNode *N = H.getNode())
+            N->setModifiedMarker();                        // Writes buffer
+          H.mergeWith(getValueDest(*CS.getInstruction())); // Returns buffer
+          ++AI; ++AI;
+
+          // Reads and writes file descriptor, merge in FILE type.
+          H = getValueDest(**AI);
+          if (DSNode *N = H.getNode()) {
+            N->setReadMarker()->setModifiedMarker();
+            const Type *ArgTy = F->getFunctionType()->getParamType(2);
+            if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+              N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+          }
+          return;
+        } else if (F->getName() == "ungetc" || F->getName() == "fputc" ||
+                   F->getName() == "fputs" || F->getName() == "putc" ||
+                   F->getName() == "ftell" || F->getName() == "rewind" ||
+                   F->getName() == "_IO_putc") {
+          // These functions read and write the memory for the file descriptor,
+          // which is passes as the last argument.
+          DSNodeHandle H = getValueDest(**--CS.arg_end());
+          if (DSNode *N = H.getNode()) {
+            N->setReadMarker()->setModifiedMarker();
+            const Type *ArgTy = *--F->getFunctionType()->param_end();
+            if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+              N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+          }
+
+          // Any pointer arguments are read.
+          for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+               AI != E; ++AI)
+            if (isPointerType((*AI)->getType()))
+              if (DSNode *N = getValueDest(**AI).getNode())
+                N->setReadMarker();   
+          return;
+        } else if (F->getName() == "fseek" || F->getName() == "fgetpos" ||
+                   F->getName() == "fsetpos") {
+          // These functions read and write the memory for the file descriptor,
+          // and read/write all other arguments.
+          DSNodeHandle H = getValueDest(**CS.arg_begin());
+          if (DSNode *N = H.getNode()) {
+            const Type *ArgTy = *--F->getFunctionType()->param_end();
+            if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+              N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+          }
+
+          // Any pointer arguments are read.
+          for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+               AI != E; ++AI)
+            if (isPointerType((*AI)->getType()))
+              if (DSNode *N = getValueDest(**AI).getNode())
+                N->setReadMarker()->setModifiedMarker();
+          return;
+        } else if (F->getName() == "printf" || F->getName() == "fprintf" ||
+                   F->getName() == "sprintf") {
+          CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+
+          if (F->getName() == "fprintf") {
+            // fprintf reads and writes the FILE argument, and applies the type
+            // to it.
+            DSNodeHandle H = getValueDest(**AI);
+            if (DSNode *N = H.getNode()) {
+              N->setModifiedMarker();
+              const Type *ArgTy = (*AI)->getType();
+              if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+                N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+            }
+          } else if (F->getName() == "sprintf") {
+            // sprintf writes the first string argument.
+            DSNodeHandle H = getValueDest(**AI++);
+            if (DSNode *N = H.getNode()) {
+              N->setModifiedMarker();
+              const Type *ArgTy = (*AI)->getType();
+              if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+                N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+            }
+          }
+
+          for (; AI != E; ++AI) {
+            // printf reads all pointer arguments.
+            if (isPointerType((*AI)->getType()))
+              if (DSNode *N = getValueDest(**AI).getNode())
+                N->setReadMarker();   
+          }
+          return;
+        } else if (F->getName() == "scanf" || F->getName() == "fscanf" ||
+                   F->getName() == "sscanf") {
+          CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+
+          if (F->getName() == "fscanf") {
+            // fscanf reads and writes the FILE argument, and applies the type
+            // to it.
+            DSNodeHandle H = getValueDest(**AI);
+            if (DSNode *N = H.getNode()) {
+              N->setReadMarker();
+              const Type *ArgTy = (*AI)->getType();
+              if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+                N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+            }
+          } else if (F->getName() == "sscanf") {
+            // sscanf reads the first string argument.
+            DSNodeHandle H = getValueDest(**AI++);
+            if (DSNode *N = H.getNode()) {
+              N->setReadMarker();
+              const Type *ArgTy = (*AI)->getType();
+              if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+                N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+            }
+          }
+
+          for (; AI != E; ++AI) {
+            // scanf writes all pointer arguments.
+            if (isPointerType((*AI)->getType()))
+              if (DSNode *N = getValueDest(**AI).getNode())
+                N->setModifiedMarker();   
+          }
+          return;
+        } else if (F->getName() == "strtok") {
+          // strtok reads and writes the first argument, returning it.  It reads
+          // its second arg.  FIXME: strtok also modifies some hidden static
+          // data.  Someday this might matter.
+          CallSite::arg_iterator AI = CS.arg_begin();
+          DSNodeHandle H = getValueDest(**AI++);
+          if (DSNode *N = H.getNode()) {
+            N->setReadMarker()->setModifiedMarker();      // Reads/Writes buffer
+            const Type *ArgTy = F->getFunctionType()->getParamType(0);
+            if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+              N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+          }
+          H.mergeWith(getValueDest(*CS.getInstruction())); // Returns buffer
+
+          H = getValueDest(**AI);       // Reads delimiter
+          if (DSNode *N = H.getNode()) {
+            N->setReadMarker();
+            const Type *ArgTy = F->getFunctionType()->getParamType(1);
+            if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+              N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+          }
+          return;
+        } else if (F->getName() == "strchr" || F->getName() == "strrchr" ||
+                   F->getName() == "strstr") {
+          // These read their arguments, and return the first one
+          DSNodeHandle H = getValueDest(**CS.arg_begin());
+          H.mergeWith(getValueDest(*CS.getInstruction())); // Returns buffer
+
+          for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+               AI != E; ++AI)
+            if (isPointerType((*AI)->getType()))
+              if (DSNode *N = getValueDest(**AI).getNode())
+                N->setReadMarker();
+    
+          if (DSNode *N = H.getNode())
+            N->setReadMarker();
+          return;
+        } else if (F->getName() == "modf" && CS.arg_end()-CS.arg_begin() == 2) {
+          // This writes its second argument, and forces it to double.
+          DSNodeHandle H = getValueDest(**--CS.arg_end());
+          if (DSNode *N = H.getNode()) {
+            N->setModifiedMarker();
+            N->mergeTypeInfo(Type::DoubleTy, H.getOffset());
+          }
+          return;
+        } else {
+          // Unknown function, warn if it returns a pointer type or takes a
+          // pointer argument.
+          bool Warn = isPointerType(CS.getInstruction()->getType());
+          if (!Warn)
+            for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end();
+                 I != E; ++I)
+              if (isPointerType((*I)->getType())) {
+                Warn = true;
+                break;
+              }
+          if (Warn)
+            std::cerr << "WARNING: Call to unknown external function '"
+                      << F->getName() << "' will cause pessimistic results!\n";
+        }
       }
 
 
@@ -499,12 +823,11 @@
   if (isPointerType(I->getType()))
     RetVal = getValueDest(*I);
 
-  DSNode *Callee = 0;
-  if (DisableDirectCallOpt || !isa<Function>(CS.getCalledValue())) {
-    Callee = getValueDest(*CS.getCalledValue()).getNode();
-    if (Callee == 0) {
-      std::cerr << "WARNING: Program is calling through a null pointer?\n"
-                << *I;
+  DSNode *CalleeNode = 0;
+  if (DisableDirectCallOpt || !isa<Function>(Callee)) {
+    CalleeNode = getValueDest(*Callee).getNode();
+    if (CalleeNode == 0) {
+      std::cerr << "WARNING: Program is calling through a null pointer?\n"<< *I;
       return;  // Calling a null pointer?
     }
   }
@@ -518,18 +841,17 @@
       Args.push_back(getValueDest(**I));
 
   // Add a new function call entry...
-  if (Callee)
-    FunctionCalls->push_back(DSCallSite(CS, RetVal, Callee, Args));
+  if (CalleeNode)
+    FunctionCalls->push_back(DSCallSite(CS, RetVal, CalleeNode, Args));
   else
-    FunctionCalls->push_back(DSCallSite(CS, RetVal, CS.getCalledFunction(),
+    FunctionCalls->push_back(DSCallSite(CS, RetVal, cast<Function>(Callee),
                                         Args));
 }
 
 void GraphBuilder::visitFreeInst(FreeInst &FI) {
   // Mark that the node is written to...
-  DSNode *N = getValueDest(*FI.getOperand(0)).getNode();
-  N->setModifiedMarker();
-  N->setHeapNodeMarker();
+  if (DSNode *N = getValueDest(*FI.getOperand(0)).getNode())
+    N->setModifiedMarker()->setHeapNodeMarker();
 }
 
 /// Handle casts...
@@ -594,6 +916,8 @@
       DSNodeHandle NewNH(NH.getNode(), NH.getOffset()+SL->MemberOffsets[i]);
       MergeConstantInitIntoNode(NewNH, cast<Constant>(CS->getOperand(i)));
     }
+  } else if (ConstantAggregateZero *CAZ = dyn_cast<ConstantAggregateZero>(C)) {
+    // Noop
   } else {
     assert(0 && "Unknown constant type!");
   }
@@ -612,20 +936,22 @@
 
   const TargetData &TD = getAnalysis<TargetData>();
 
+  {
+    GraphBuilder GGB(*GlobalsGraph);
+    
+    // Add initializers for all of the globals to the globals graph...
+    for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
+      if (!I->isExternal())
+        GGB.mergeInGlobalInitializer(I);
+  }
+
   // Calculate all of the graphs...
   for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
     if (!I->isExternal())
       DSInfo.insert(std::make_pair(I, new DSGraph(TD, *I, GlobalsGraph)));
 
-  GraphBuilder GGB(*GlobalsGraph);
-
-  // Add initializers for all of the globals to the globals graph...
-  for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
-    if (!I->isExternal())
-      GGB.mergeInGlobalInitializer(I);
-
-  GlobalsGraph->markIncompleteNodes(DSGraph::MarkFormalArgs);
   GlobalsGraph->removeTriviallyDeadNodes();
+  GlobalsGraph->markIncompleteNodes(DSGraph::MarkFormalArgs);
   return false;
 }
 


Index: llvm/lib/Analysis/DataStructure/Printer.cpp
diff -u llvm/lib/Analysis/DataStructure/Printer.cpp:1.62 llvm/lib/Analysis/DataStructure/Printer.cpp:1.62.4.1
--- llvm/lib/Analysis/DataStructure/Printer.cpp:1.62	Wed Nov 12 23:05:41 2003
+++ llvm/lib/Analysis/DataStructure/Printer.cpp	Mon Mar  1 17:58:12 2004
@@ -29,8 +29,9 @@
 //
 namespace {
   cl::opt<bool> OnlyPrintMain("only-print-main-ds", cl::ReallyHidden);
-  Statistic<> MaxGraphSize   ("dsnode", "Maximum graph size");
-  Statistic<> NumFoldedNodes ("dsnode", "Number of folded nodes (in final graph)");
+  cl::opt<bool> DontPrintAnything("dont-print-ds", cl::ReallyHidden);
+  Statistic<> MaxGraphSize   ("dsa", "Maximum graph size");
+  Statistic<> NumFoldedNodes ("dsa", "Number of folded nodes (in final graph)");
 }
 
 void DSNode::dump() const { print(std::cerr, 0); }
@@ -38,6 +39,9 @@
 static std::string getCaption(const DSNode *N, const DSGraph *G) {
   std::stringstream OS;
   Module *M = 0;
+
+  if (G) G = N->getParentGraph();
+
   // Get the module from ONE of the functions in the graph it is available.
   if (G && !G->getReturnNodes().empty())
     M = G->getReturnNodes().begin()->first->getParent();
@@ -248,10 +252,12 @@
           << Gr.getGraphSize() << "+" << NumCalls << "]\n";
       }
 
-      if (MaxGraphSize < Gr.getNodes().size())
-        MaxGraphSize = Gr.getNodes().size();
-      for (unsigned i = 0, e = Gr.getNodes().size(); i != e; ++i)
-        if (Gr.getNodes()[i]->isNodeCompletelyFolded())
+      unsigned GraphSize = Gr.getGraphSize();
+      if (MaxGraphSize < GraphSize) MaxGraphSize = GraphSize;
+
+      for (DSGraph::node_iterator NI = Gr.node_begin(), E = Gr.node_end();
+           NI != E; ++NI)
+        if ((*NI)->isNodeCompletelyFolded())
           ++NumFoldedNodes;
     }
 
@@ -272,18 +278,22 @@
 
 // print - Print out the analysis results...
 void LocalDataStructures::print(std::ostream &O, const Module *M) const {
+  if (DontPrintAnything) return;
   printCollection(*this, O, M, "ds.");
 }
 
 void BUDataStructures::print(std::ostream &O, const Module *M) const {
+  if (DontPrintAnything) return;
   printCollection(*this, O, M, "bu.");
 }
 
 void TDDataStructures::print(std::ostream &O, const Module *M) const {
+  if (DontPrintAnything) return;
   printCollection(*this, O, M, "td.");
 }
 
 void CompleteBUDataStructures::print(std::ostream &O, const Module *M) const {
+  if (DontPrintAnything) return;
   printCollection(*this, O, M, "cbu.");
 }
 


Index: llvm/lib/Analysis/DataStructure/Steensgaard.cpp
diff -u llvm/lib/Analysis/DataStructure/Steensgaard.cpp:1.35 llvm/lib/Analysis/DataStructure/Steensgaard.cpp:1.35.4.1
--- llvm/lib/Analysis/DataStructure/Steensgaard.cpp:1.35	Wed Nov 12 17:11:14 2003
+++ llvm/lib/Analysis/DataStructure/Steensgaard.cpp	Mon Mar  1 17:58:12 2004
@@ -63,6 +63,10 @@
     // alias - This is the only method here that does anything interesting...
     AliasResult alias(const Value *V1, unsigned V1Size,
                       const Value *V2, unsigned V2Size);
+
+    bool pointsToConstantMemory(const Value *P) {
+      return getAnalysis<AliasAnalysis>().pointsToConstantMemory(P);
+    }
     
   private:
     void ResolveFunctionCall(Function *F, const DSCallSite &Call,
@@ -130,7 +134,8 @@
       {  // Scope to free NodeMap memory ASAP
         DSGraph::NodeMapTy NodeMap;
         const DSGraph &FDSG = LDS.getDSGraph(*I);
-        ResultGraph->cloneInto(FDSG, ValMap, RetValMap, NodeMap);
+        ResultGraph->cloneInto(FDSG, ValMap, RetValMap, NodeMap,
+                               DSGraph::UpdateInlinedGlobals);
       }
 
       // Incorporate the inlined Function's ScalarMap into the global


Index: llvm/lib/Analysis/DataStructure/TopDownClosure.cpp
diff -u llvm/lib/Analysis/DataStructure/TopDownClosure.cpp:1.60 llvm/lib/Analysis/DataStructure/TopDownClosure.cpp:1.60.4.1
--- llvm/lib/Analysis/DataStructure/TopDownClosure.cpp:1.60	Wed Nov 12 17:11:14 2003
+++ llvm/lib/Analysis/DataStructure/TopDownClosure.cpp	Mon Mar  1 17:58:12 2004
@@ -60,15 +60,14 @@
   // they are accessible outside this compilation unit.  Currently, these
   // arguments are functions which are reachable by global variables in the
   // globals graph.
-  const DSGraph::ScalarMapTy &GGSM = GlobalsGraph->getScalarMap();
+  const DSScalarMap &GGSM = GlobalsGraph->getScalarMap();
   hash_set<DSNode*> Visited;
-  for (DSGraph::ScalarMapTy::const_iterator I = GGSM.begin(), E = GGSM.end();
+  for (DSScalarMap::global_iterator I = GGSM.global_begin(), E = GGSM.global_end();
        I != E; ++I)
-    if (isa<GlobalValue>(I->first))
-      markReachableFunctionsExternallyAccessible(I->second.getNode(), Visited);
+    markReachableFunctionsExternallyAccessible(GGSM.find(*I)->second.getNode(), Visited);
 
   // Loop over unresolved call nodes.  Any functions passed into (but not
-  // returned!?) from unresolvable call nodes may be invoked outside of the
+  // returned!) from unresolvable call nodes may be invoked outside of the
   // current module.
   const std::vector<DSCallSite> &Calls = GlobalsGraph->getAuxFunctionCalls();
   for (unsigned i = 0, e = Calls.size(); i != e; ++i) {
@@ -108,6 +107,8 @@
   }
 
   ArgsRemainIncomplete.clear();
+  GlobalsGraph->removeTriviallyDeadNodes();
+
   return false;
 }
 
@@ -176,7 +177,6 @@
 
 void TDDataStructures::inlineGraphIntoCallees(DSGraph &Graph) {
   // Recompute the Incomplete markers and eliminate unreachable nodes.
-  Graph.removeTriviallyDeadNodes();
   Graph.maskIncompleteMarkers();
 
   // If any of the functions has incomplete incoming arguments, don't mark any
@@ -228,80 +228,59 @@
   const BUDataStructures::ActualCalleesTy &ActualCallees =
     getAnalysis<BUDataStructures>().getActualCallees();
 
-  // Loop over all the call sites and all the callees at each call site.
-  // Clone and merge the reachable subgraph from the call into callee's graph.
-  // 
+  // Loop over all the call sites and all the callees at each call site.  Build
+  // a mapping from called DSGraph's to the call sites in this function that
+  // invoke them.  This is useful because we can be more efficient if there are
+  // multiple call sites to the callees in the graph from this caller.
+  std::multimap<DSGraph*, std::pair<Function*, const DSCallSite*> > CallSites;
+
   for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i) {
     Instruction *CallI = FunctionCalls[i].getCallSite().getInstruction();
     // For each function in the invoked function list at this call site...
     std::pair<BUDataStructures::ActualCalleesTy::const_iterator,
       BUDataStructures::ActualCalleesTy::const_iterator>
           IP = ActualCallees.equal_range(CallI);
-
-    // Multiple callees may have the same graph, so try to inline and merge
-    // only once for each <callSite,calleeGraph> pair, not once for each
-    // <callSite,calleeFunction> pair; the latter will be correct but slower.
-    hash_set<DSGraph*> GraphsSeen;
-
     // Loop over each actual callee at this call site
     for (BUDataStructures::ActualCalleesTy::const_iterator I = IP.first;
          I != IP.second; ++I) {
       DSGraph& CalleeGraph = getDSGraph(*I->second);
       assert(&CalleeGraph != &Graph && "TD need not inline graph into self!");
 
-      // if this callee graph is already done at this site, skip this callee
-      if (GraphsSeen.find(&CalleeGraph) != GraphsSeen.end())
-        continue;
-      GraphsSeen.insert(&CalleeGraph);
-
-      // Get the root nodes for cloning the reachable subgraph into each callee:
-      // -- all global nodes that appear in both the caller and the callee
-      // -- return value at this call site, if any
-      // -- actual arguments passed at this call site
-      // -- callee node at this call site, if this is an indirect call (this may
-      //    not be needed for merging, but allows us to create CS and therefore
-      //    simplify the merging below).
-      hash_set<const DSNode*> RootNodeSet;
-      for (DSGraph::ScalarMapTy::const_iterator
-             SI = CalleeGraph.getScalarMap().begin(),
-             SE = CalleeGraph.getScalarMap().end(); SI != SE; ++SI)
-        if (GlobalValue* GV = dyn_cast<GlobalValue>(SI->first)) {
-          DSGraph::ScalarMapTy::const_iterator GI=Graph.getScalarMap().find(GV);
-          if (GI != Graph.getScalarMap().end())
-            RootNodeSet.insert(GI->second.getNode());
-        }
-
-      if (const DSNode* RetNode = FunctionCalls[i].getRetVal().getNode())
-        RootNodeSet.insert(RetNode);
-
-      for (unsigned j=0, N=FunctionCalls[i].getNumPtrArgs(); j < N; ++j)
-        if (const DSNode* ArgTarget = FunctionCalls[i].getPtrArg(j).getNode())
-          RootNodeSet.insert(ArgTarget);
+      CallSites.insert(std::make_pair(&CalleeGraph,
+                           std::make_pair(I->second, &FunctionCalls[i])));
+    }
+  }
 
-      if (FunctionCalls[i].isIndirectCall())
-        RootNodeSet.insert(FunctionCalls[i].getCalleeNode());
+  // Now that we built the mapping, actually perform the inlining a callee graph
+  // at a time.
+  std::multimap<DSGraph*,std::pair<Function*,const DSCallSite*> >::iterator CSI;
+  for (CSI = CallSites.begin(); CSI != CallSites.end(); ) {
+    DSGraph &CalleeGraph = *CSI->first;
+    // Iterate through all of the call sites of this graph, cloning and merging
+    // any nodes required by the call.
+    ReachabilityCloner RC(CalleeGraph, Graph, DSGraph::StripModRefBits);
+
+    // Clone over any global nodes that appear in both graphs.
+    for (DSScalarMap::global_iterator
+           SI = CalleeGraph.getScalarMap().global_begin(),
+           SE = CalleeGraph.getScalarMap().global_end(); SI != SE; ++SI) {
+      DSScalarMap::const_iterator GI = Graph.getScalarMap().find(*SI);
+      if (GI != Graph.getScalarMap().end())
+        RC.merge(CalleeGraph.getNodeForValue(*SI), GI->second);
+    }
 
+    // Loop over all of the distinct call sites in the caller of the callee.
+    for (; CSI != CallSites.end() && CSI->first == &CalleeGraph; ++CSI) {
+      Function &CF = *CSI->second.first;
+      const DSCallSite &CS = *CSI->second.second;
       DEBUG(std::cerr << "     [TD] Resolving arguments for callee graph '"
             << CalleeGraph.getFunctionNames()
-            << "': " << I->second->getFunctionType()->getNumParams()
-            << " args\n          at call site (DSCallSite*) 0x"
-            << &FunctionCalls[i] << "\n");
+            << "': " << CF.getFunctionType()->getNumParams()
+            << " args\n          at call site (DSCallSite*) 0x" << &CS << "\n");
       
-      DSGraph::NodeMapTy NodeMapInCallee; // map from nodes to clones in callee
-      DSGraph::NodeMapTy CompletedMap;    // unused map for nodes not to do
-      CalleeGraph.cloneReachableSubgraph(Graph, RootNodeSet,
-                                         NodeMapInCallee, CompletedMap,
-                                         DSGraph::StripModRefBits |
-                                         DSGraph::KeepAllocaBit);
-
-      // Transform our call site info into the cloned version for CalleeGraph
-      DSCallSite CS(FunctionCalls[i], NodeMapInCallee);
-
-      // Get the formal argument and return nodes for the called function
-      // and merge them with the cloned subgraph.  Global nodes were merged  
-      // already by cloneReachableSubgraph() above.
-      CalleeGraph.getCallSiteForArguments(*I->second).mergeWith(CS);
-
+      // Get the formal argument and return nodes for the called function and
+      // merge them with the cloned subgraph.
+      RC.mergeCallSite(CalleeGraph.getCallSiteForArguments(CF), CS);
       ++NumTDInlines;
     }
   }





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