diff --git a/include/llvm/Analysis/DSSupport.h b/include/llvm/Analysis/DSSupport.h
index aff7abcb6ec..f80423b0d98 100644
--- a/include/llvm/Analysis/DSSupport.h
+++ b/include/llvm/Analysis/DSSupport.h
@@ -7,11 +7,9 @@
 #ifndef LLVM_ANALYSIS_DSSUPPORT_H
 #define LLVM_ANALYSIS_DSSUPPORT_H
 
-#include <vector>
 #include <functional>
-#include <string>
-#include <cassert>
 #include "Support/hash_set"
+#include "llvm/Support/CallSite.h"
 
 class Function;
 class CallInst;
@@ -127,7 +125,7 @@ namespace std {
 /// the DSNode handles for the function arguments.
 /// 
 class DSCallSite {
-  CallInst    *Inst;                 // Actual call site
+  CallSite     Site;                 // Actual call site
   Function    *CalleeF;              // The function called (direct call)
   DSNodeHandle CalleeN;              // The function node called (indirect call)
   DSNodeHandle RetVal;               // Returned value
@@ -160,21 +158,21 @@ public:
   /// Constructor.  Note - This ctor destroys the argument vector passed in.  On
   /// exit, the argument vector is empty.
   ///
-  DSCallSite(CallInst &inst, const DSNodeHandle &rv, DSNode *Callee,
+  DSCallSite(CallSite CS, const DSNodeHandle &rv, DSNode *Callee,
              std::vector<DSNodeHandle> &Args)
-    : Inst(&inst), CalleeF(0), CalleeN(Callee), RetVal(rv) {
+    : Site(CS), CalleeF(0), CalleeN(Callee), RetVal(rv) {
     assert(Callee && "Null callee node specified for call site!");
     Args.swap(CallArgs);
   }
-  DSCallSite(CallInst &inst, const DSNodeHandle &rv, Function *Callee,
+  DSCallSite(CallSite CS, const DSNodeHandle &rv, Function *Callee,
              std::vector<DSNodeHandle> &Args)
-    : Inst(&inst), CalleeF(Callee), RetVal(rv) {
+    : Site(CS), CalleeF(Callee), RetVal(rv) {
     assert(Callee && "Null callee function specified for call site!");
     Args.swap(CallArgs);
   }
 
   DSCallSite(const DSCallSite &DSCS)   // Simple copy ctor
-    : Inst(DSCS.Inst), CalleeF(DSCS.CalleeF), CalleeN(DSCS.CalleeN),
+    : Site(DSCS.Site), CalleeF(DSCS.CalleeF), CalleeN(DSCS.CalleeN),
       RetVal(DSCS.RetVal), CallArgs(DSCS.CallArgs) {}
 
   /// Mapping copy constructor - This constructor takes a preexisting call site
@@ -183,7 +181,7 @@ public:
   ///
   template<typename MapTy>
   DSCallSite(const DSCallSite &FromCall, const MapTy &NodeMap) {
-    Inst = FromCall.Inst;
+    Site = FromCall.Site;
     InitNH(RetVal, FromCall.RetVal, NodeMap);
     InitNH(CalleeN, FromCall.CalleeN, NodeMap);
     CalleeF = FromCall.CalleeF;
@@ -194,7 +192,7 @@ public:
   }
 
   const DSCallSite &operator=(const DSCallSite &RHS) {
-    Inst     = RHS.Inst;
+    Site     = RHS.Site;
     CalleeF  = RHS.CalleeF;
     CalleeN  = RHS.CalleeN;
     RetVal   = RHS.RetVal;
@@ -212,7 +210,7 @@ public:
 
   // Accessor functions...
   Function           &getCaller()     const;
-  CallInst           &getCallInst()   const { return *Inst; }
+  CallSite            getCallSite()   const { return Site; }
         DSNodeHandle &getRetVal()           { return RetVal; }
   const DSNodeHandle &getRetVal()     const { return RetVal; }
 
@@ -236,7 +234,7 @@ public:
 
   void swap(DSCallSite &CS) {
     if (this != &CS) {
-      std::swap(Inst, CS.Inst);
+      std::swap(Site, CS.Site);
       std::swap(RetVal, CS.RetVal);
       std::swap(CalleeN, CS.CalleeN);
       std::swap(CalleeF, CS.CalleeF);
diff --git a/include/llvm/Analysis/DataStructure.h b/include/llvm/Analysis/DataStructure.h
index d8f30d25d09..f52bb4b60fb 100644
--- a/include/llvm/Analysis/DataStructure.h
+++ b/include/llvm/Analysis/DataStructure.h
@@ -11,10 +11,9 @@
 #include "Support/hash_set"
 
 class Type;
-class CallInst;
+class Instruction;
 class DSGraph;
 class DSNode;
-class DSCallSite;
 
 // FIXME: move this stuff to a private header
 namespace DataStructureAnalysis {
@@ -75,7 +74,7 @@ class BUDataStructures : public Pass {
   // DSInfo, one graph for each function
   hash_map<Function*, DSGraph*> DSInfo;
   DSGraph *GlobalsGraph;
-  hash_multimap<CallInst*, Function*> ActualCallees;
+  hash_multimap<Instruction*, Function*> ActualCallees;
 public:
   ~BUDataStructures() { releaseMemory(); }
 
@@ -106,7 +105,7 @@ public:
     AU.addRequired<LocalDataStructures>();
   }
 
-  typedef hash_multimap<CallInst*, Function*> ActualCalleesTy;
+  typedef hash_multimap<Instruction*, Function*> ActualCalleesTy;
   const ActualCalleesTy &getActualCallees() const {
     return ActualCallees;
   }
diff --git a/include/llvm/Analysis/DataStructure/DSSupport.h b/include/llvm/Analysis/DataStructure/DSSupport.h
index aff7abcb6ec..f80423b0d98 100644
--- a/include/llvm/Analysis/DataStructure/DSSupport.h
+++ b/include/llvm/Analysis/DataStructure/DSSupport.h
@@ -7,11 +7,9 @@
 #ifndef LLVM_ANALYSIS_DSSUPPORT_H
 #define LLVM_ANALYSIS_DSSUPPORT_H
 
-#include <vector>
 #include <functional>
-#include <string>
-#include <cassert>
 #include "Support/hash_set"
+#include "llvm/Support/CallSite.h"
 
 class Function;
 class CallInst;
@@ -127,7 +125,7 @@ namespace std {
 /// the DSNode handles for the function arguments.
 /// 
 class DSCallSite {
-  CallInst    *Inst;                 // Actual call site
+  CallSite     Site;                 // Actual call site
   Function    *CalleeF;              // The function called (direct call)
   DSNodeHandle CalleeN;              // The function node called (indirect call)
   DSNodeHandle RetVal;               // Returned value
@@ -160,21 +158,21 @@ public:
   /// Constructor.  Note - This ctor destroys the argument vector passed in.  On
   /// exit, the argument vector is empty.
   ///
-  DSCallSite(CallInst &inst, const DSNodeHandle &rv, DSNode *Callee,
+  DSCallSite(CallSite CS, const DSNodeHandle &rv, DSNode *Callee,
              std::vector<DSNodeHandle> &Args)
-    : Inst(&inst), CalleeF(0), CalleeN(Callee), RetVal(rv) {
+    : Site(CS), CalleeF(0), CalleeN(Callee), RetVal(rv) {
     assert(Callee && "Null callee node specified for call site!");
     Args.swap(CallArgs);
   }
-  DSCallSite(CallInst &inst, const DSNodeHandle &rv, Function *Callee,
+  DSCallSite(CallSite CS, const DSNodeHandle &rv, Function *Callee,
              std::vector<DSNodeHandle> &Args)
-    : Inst(&inst), CalleeF(Callee), RetVal(rv) {
+    : Site(CS), CalleeF(Callee), RetVal(rv) {
     assert(Callee && "Null callee function specified for call site!");
     Args.swap(CallArgs);
   }
 
   DSCallSite(const DSCallSite &DSCS)   // Simple copy ctor
-    : Inst(DSCS.Inst), CalleeF(DSCS.CalleeF), CalleeN(DSCS.CalleeN),
+    : Site(DSCS.Site), CalleeF(DSCS.CalleeF), CalleeN(DSCS.CalleeN),
       RetVal(DSCS.RetVal), CallArgs(DSCS.CallArgs) {}
 
   /// Mapping copy constructor - This constructor takes a preexisting call site
@@ -183,7 +181,7 @@ public:
   ///
   template<typename MapTy>
   DSCallSite(const DSCallSite &FromCall, const MapTy &NodeMap) {
-    Inst = FromCall.Inst;
+    Site = FromCall.Site;
     InitNH(RetVal, FromCall.RetVal, NodeMap);
     InitNH(CalleeN, FromCall.CalleeN, NodeMap);
     CalleeF = FromCall.CalleeF;
@@ -194,7 +192,7 @@ public:
   }
 
   const DSCallSite &operator=(const DSCallSite &RHS) {
-    Inst     = RHS.Inst;
+    Site     = RHS.Site;
     CalleeF  = RHS.CalleeF;
     CalleeN  = RHS.CalleeN;
     RetVal   = RHS.RetVal;
@@ -212,7 +210,7 @@ public:
 
   // Accessor functions...
   Function           &getCaller()     const;
-  CallInst           &getCallInst()   const { return *Inst; }
+  CallSite            getCallSite()   const { return Site; }
         DSNodeHandle &getRetVal()           { return RetVal; }
   const DSNodeHandle &getRetVal()     const { return RetVal; }
 
@@ -236,7 +234,7 @@ public:
 
   void swap(DSCallSite &CS) {
     if (this != &CS) {
-      std::swap(Inst, CS.Inst);
+      std::swap(Site, CS.Site);
       std::swap(RetVal, CS.RetVal);
       std::swap(CalleeN, CS.CalleeN);
       std::swap(CalleeF, CS.CalleeF);
diff --git a/include/llvm/Analysis/DataStructure/DataStructure.h b/include/llvm/Analysis/DataStructure/DataStructure.h
index d8f30d25d09..f52bb4b60fb 100644
--- a/include/llvm/Analysis/DataStructure/DataStructure.h
+++ b/include/llvm/Analysis/DataStructure/DataStructure.h
@@ -11,10 +11,9 @@
 #include "Support/hash_set"
 
 class Type;
-class CallInst;
+class Instruction;
 class DSGraph;
 class DSNode;
-class DSCallSite;
 
 // FIXME: move this stuff to a private header
 namespace DataStructureAnalysis {
@@ -75,7 +74,7 @@ class BUDataStructures : public Pass {
   // DSInfo, one graph for each function
   hash_map<Function*, DSGraph*> DSInfo;
   DSGraph *GlobalsGraph;
-  hash_multimap<CallInst*, Function*> ActualCallees;
+  hash_multimap<Instruction*, Function*> ActualCallees;
 public:
   ~BUDataStructures() { releaseMemory(); }
 
@@ -106,7 +105,7 @@ public:
     AU.addRequired<LocalDataStructures>();
   }
 
-  typedef hash_multimap<CallInst*, Function*> ActualCalleesTy;
+  typedef hash_multimap<Instruction*, Function*> ActualCalleesTy;
   const ActualCalleesTy &getActualCallees() const {
     return ActualCallees;
   }
diff --git a/include/llvm/Analysis/IPModRef.h b/include/llvm/Analysis/IPModRef.h
index eed264f9785..015618d0572 100644
--- a/include/llvm/Analysis/IPModRef.h
+++ b/include/llvm/Analysis/IPModRef.h
@@ -45,7 +45,10 @@
 
 class Module;
 class Function;
+class CallSite;
+class Instruction;
 class CallInst;
+class InvokeInst;
 class DSNode;
 class DSGraph;
 class DSNodeHandle;
@@ -117,15 +120,15 @@ class FunctionModRefInfo {
   IPModRef&             IPModRefObj;        // The IPModRef Object owning this
   DSGraph*              funcTDGraph;        // Top-down DS graph for function
   ModRefInfo            funcModRefInfo;     // ModRefInfo for the function body
-  std::map<const CallInst*, ModRefInfo*>
+  std::map<const Instruction*, ModRefInfo*>
                         callSiteModRefInfo; // ModRefInfo for each callsite
   std::map<const DSNode*, unsigned> NodeIds;
 
   friend class IPModRef;
 
   void          computeModRef   (const Function &func);
-  void          computeModRef   (const CallInst& callInst);
-  DSGraph *ResolveCallSiteModRefInfo(CallInst &CI,
+  void          computeModRef   (CallSite call);
+  DSGraph *ResolveCallSiteModRefInfo(CallSite CS,
                                 hash_map<const DSNode*, DSNodeHandle> &NodeMap);
 
 public:
@@ -145,9 +148,14 @@ public:
     return &funcModRefInfo;
   }
   const ModRefInfo*     getModRefInfo  (const CallInst& callInst) const {
-    std::map<const CallInst*, ModRefInfo*>::const_iterator I = 
-      callSiteModRefInfo.find(&callInst);
-    return (I == callSiteModRefInfo.end())? NULL : I->second;
+    std::map<const Instruction*, ModRefInfo*>::const_iterator I = 
+      callSiteModRefInfo.find((Instruction*)&callInst);
+    return (I == callSiteModRefInfo.end()) ? NULL : I->second;
+  }
+  const ModRefInfo*     getModRefInfo  (const InvokeInst& II) const {
+    std::map<const Instruction*, ModRefInfo*>::const_iterator I = 
+      callSiteModRefInfo.find((Instruction*)&II);
+    return (I == callSiteModRefInfo.end()) ? NULL : I->second;
   }
 
   // Get the nodeIds used to index all Mod/Ref information for current function
diff --git a/lib/Analysis/DataStructure/BottomUpClosure.cpp b/lib/Analysis/DataStructure/BottomUpClosure.cpp
index dd141f2daf6..f5d435fe45d 100644
--- a/lib/Analysis/DataStructure/BottomUpClosure.cpp
+++ b/lib/Analysis/DataStructure/BottomUpClosure.cpp
@@ -253,7 +253,8 @@ void BUDataStructures::calculateGraph(DSGraph &Graph) {
       Graph.mergeInGraph(CS, *Callee, Graph, 0);
 
     } else {
-      ActualCallees.insert(std::make_pair(&CS.getCallInst(), Callee));
+      ActualCallees.insert(std::make_pair(CS.getCallSite().getInstruction(),
+                                          Callee));
 
       // Get the data structure graph for the called function.
       //
diff --git a/lib/Analysis/DataStructure/DataStructure.cpp b/lib/Analysis/DataStructure/DataStructure.cpp
index 24bed38cc85..0a6fa57aa07 100644
--- a/lib/Analysis/DataStructure/DataStructure.cpp
+++ b/lib/Analysis/DataStructure/DataStructure.cpp
@@ -709,7 +709,7 @@ void DSNode::mergeWith(const DSNodeHandle &NH, unsigned Offset) {
 
 // Define here to avoid including iOther.h and BasicBlock.h in DSGraph.h
 Function &DSCallSite::getCaller() const {
-  return *Inst->getParent()->getParent();
+  return *Site.getInstruction()->getParent()->getParent();
 }
 
 
@@ -1044,7 +1044,7 @@ DSCallSite DSGraph::getCallSiteForArguments(Function &F) const {
     if (isPointerType(I->getType()))
       Args.push_back(getScalarMap().find(I)->second);
 
-  return DSCallSite(*(CallInst*)0, getReturnNodeFor(F), &F, Args);
+  return DSCallSite(CallSite(), getReturnNodeFor(F), &F, Args);
 }
 
 
diff --git a/lib/Analysis/DataStructure/DataStructureStats.cpp b/lib/Analysis/DataStructure/DataStructureStats.cpp
index 674f689a685..ffd560b2457 100644
--- a/lib/Analysis/DataStructure/DataStructureStats.cpp
+++ b/lib/Analysis/DataStructure/DataStructureStats.cpp
@@ -68,7 +68,7 @@ void DSGraphStats::countCallees(const Function& F) {
 
   const std::vector<DSCallSite> &callSites = TDGraph->getFunctionCalls();
   for (unsigned i = 0, N = callSites.size(); i != N; ++i)
-    if (isIndirectCallee(callSites[i].getCallInst().getCalledValue())) {
+    if (isIndirectCallee(callSites[i].getCallSite().getCalledValue())) {
       // This is an indirect function call
       const std::vector<GlobalValue*> &Callees =
         callSites[i].getCalleeNode()->getGlobals();
@@ -76,8 +76,9 @@ void DSGraphStats::countCallees(const Function& F) {
         totalNumCallees  += Callees.size();
         ++numIndirectCalls;
       } else
-        std::cerr << "WARNING: No callee in Function " << F.getName()
-                  << "at call:\n" << callSites[i].getCallInst();
+        std::cerr << "WARNING: No callee in Function '" << F.getName()
+                  << "' at call: \n"
+                  << *callSites[i].getCallSite().getInstruction();
     }
   
   TotalNumCallees  += totalNumCallees;
diff --git a/lib/Analysis/DataStructure/IPModRef.cpp b/lib/Analysis/DataStructure/IPModRef.cpp
index a90b5c62b02..e7366a0536c 100644
--- a/lib/Analysis/DataStructure/IPModRef.cpp
+++ b/lib/Analysis/DataStructure/IPModRef.cpp
@@ -61,7 +61,7 @@ FunctionModRefInfo::FunctionModRefInfo(const Function& func,
 
 FunctionModRefInfo::~FunctionModRefInfo()
 {
-  for(std::map<const CallInst*, ModRefInfo*>::iterator
+  for(std::map<const Instruction*, ModRefInfo*>::iterator
         I=callSiteModRefInfo.begin(), E=callSiteModRefInfo.end(); I != E; ++I)
     delete(I->second);
 
@@ -98,7 +98,7 @@ void FunctionModRefInfo::computeModRef(const Function &func)
   // The call sites are recorded in the TD graph.
   const std::vector<DSCallSite>& callSites = funcTDGraph->getFunctionCalls();
   for (unsigned i = 0, N = callSites.size(); i < N; ++i)
-    computeModRef(callSites[i].getCallInst());
+    computeModRef(callSites[i].getCallSite());
 }
 
 
@@ -117,25 +117,22 @@ void FunctionModRefInfo::computeModRef(const Function &func)
 //       requested information (because the call site calls an external
 //       function or we cannot determine the complete set of functions invoked).
 //
-DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI,
+DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallSite CS,
                                hash_map<const DSNode*, DSNodeHandle> &NodeMap)
 {
   // Step #0: Quick check if we are going to fail anyway: avoid
   // all the graph cloning and map copying in steps #1 and #2.
   // 
-  if (const Function *F = CI.getCalledFunction())
-    {
-      if (F->isExternal())
-        return 0;   // We cannot compute Mod/Ref info for this callsite...
-    }
-  else
-    {
-      // Eventually, should check here if any callee is external.
-      // For now we are not handling this case anyway.
-      std::cerr << "IP Mod/Ref indirect call not implemented yet: "
-              << "Being conservative\n";
+  if (const Function *F = CS.getCalledFunction()) {
+    if (F->isExternal())
       return 0;   // We cannot compute Mod/Ref info for this callsite...
-    }
+  } else {
+    // Eventually, should check here if any callee is external.
+    // For now we are not handling this case anyway.
+    std::cerr << "IP Mod/Ref indirect call not implemented yet: "
+              << "Being conservative\n";
+    return 0;   // We cannot compute Mod/Ref info for this callsite...
+  }
 
   // Step #1: Clone the top-down graph...
   DSGraph *Result = new DSGraph(*funcTDGraph, NodeMap);
@@ -144,7 +141,7 @@ DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI,
   Result->maskNodeTypes(~(DSNode::Modified | DSNode::Read));
 
   // Step #3: clone the bottom up graphs for the callees into the caller graph
-  if (Function *F = CI.getCalledFunction())
+  if (Function *F = CS.getCalledFunction())
     {
       assert(!F->isExternal());
 
@@ -152,17 +149,18 @@ DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI,
 
       // If the call returns a value, make sure to merge the nodes...
       DSNodeHandle RetVal;
-      if (DS::isPointerType(CI.getType()))
-        RetVal = Result->getNodeForValue(&CI);
+      if (DS::isPointerType(CS.getInstruction()->getType()))
+        RetVal = Result->getNodeForValue(CS.getInstruction());
 
       // Populate the arguments list...
       std::vector<DSNodeHandle> Args;
-      for (unsigned i = 1, e = CI.getNumOperands(); i != e; ++i)
-        if (DS::isPointerType(CI.getOperand(i)->getType()))
-          Args.push_back(Result->getNodeForValue(CI.getOperand(i)));
+      for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end();
+           I != E; ++I)
+        if (DS::isPointerType((*I)->getType()))
+          Args.push_back(Result->getNodeForValue(*I));
 
       // Build the call site...
-      DSCallSite CS(CI, RetVal, F, Args);
+      DSCallSite CS(CS, RetVal, F, Args);
 
       // Perform the merging now of the graph for the callee, which will
       // come with mod/ref bits set...
@@ -187,16 +185,15 @@ DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI,
 // and then inlining the callee's BU graph into the caller's TD graph.
 // 
 void
-FunctionModRefInfo::computeModRef(const CallInst& callInst)
+FunctionModRefInfo::computeModRef(CallSite CS)
 {
   // Allocate the mod/ref info for the call site.  Bits automatically cleared.
   ModRefInfo* callModRefInfo = new ModRefInfo(funcTDGraph->getGraphSize());
-  callSiteModRefInfo[&callInst] = callModRefInfo;
+  callSiteModRefInfo[CS.getInstruction()] = callModRefInfo;
 
   // Get a copy of the graph for the callee with the callee inlined
   hash_map<const DSNode*, DSNodeHandle> NodeMap;
-  DSGraph* csgp = ResolveCallSiteModRefInfo(const_cast<CallInst&>(callInst),
-                                            NodeMap);
+  DSGraph* csgp = ResolveCallSiteModRefInfo(CS, NodeMap);
   if (!csgp)
     { // Callee's side effects are unknown: mark all nodes Mod and Ref.
       // Eventually this should only mark nodes visible to the callee, i.e.,
@@ -323,7 +320,7 @@ void FunctionModRefInfo::print(std::ostream &O) const
 
   // Second: Print Globals and Locals modified at each call site in function
   // 
-  for (std::map<const CallInst*, ModRefInfo*>::const_iterator
+  for (std::map<const Instruction *, ModRefInfo*>::const_iterator
          CI = callSiteModRefInfo.begin(), CE = callSiteModRefInfo.end();
        CI != CE; ++CI)
     {
diff --git a/lib/Analysis/DataStructure/Local.cpp b/lib/Analysis/DataStructure/Local.cpp
index cd81aab35f6..1b082833de5 100644
--- a/lib/Analysis/DataStructure/Local.cpp
+++ b/lib/Analysis/DataStructure/Local.cpp
@@ -7,14 +7,11 @@
 
 #include "llvm/Analysis/DataStructure.h"
 #include "llvm/Analysis/DSGraph.h"
-#include "llvm/iMemory.h"
-#include "llvm/iTerminators.h"
-#include "llvm/iPHINode.h"
-#include "llvm/iOther.h"
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Function.h"
 #include "llvm/GlobalVariable.h"
+#include "llvm/Instructions.h"
 #include "llvm/Support/InstVisitor.h"
 #include "llvm/Target/TargetData.h"
 #include "Support/CommandLine.h"
@@ -96,11 +93,13 @@ namespace {
     void visitLoadInst(LoadInst &LI);
     void visitStoreInst(StoreInst &SI);
     void visitCallInst(CallInst &CI);
+    void visitInvokeInst(InvokeInst &II);
     void visitSetCondInst(SetCondInst &SCI) {}  // SetEQ & friends are ignored
     void visitFreeInst(FreeInst &FI);
     void visitCastInst(CastInst &CI);
     void visitInstruction(Instruction &I);
 
+    void visitCallSite(CallSite CS);
   private:
     // Helper functions used to implement the visitation functions...
 
@@ -405,29 +404,38 @@ void GraphBuilder::visitReturnInst(ReturnInst &RI) {
 }
 
 void GraphBuilder::visitCallInst(CallInst &CI) {
+  visitCallSite(&CI);
+}
+
+void GraphBuilder::visitInvokeInst(InvokeInst &II) {
+  visitCallSite(&II);
+}
+
+void GraphBuilder::visitCallSite(CallSite CS) {
   // Set up the return value...
   DSNodeHandle RetVal;
-  if (isPointerType(CI.getType()))
-    RetVal = getValueDest(CI);
+  Instruction *I = CS.getInstruction();
+  if (isPointerType(I->getType()))
+    RetVal = getValueDest(*I);
 
   DSNode *Callee = 0;
-  if (DisableDirectCallOpt || !isa<Function>(CI.getOperand(0)))
-    Callee = getValueDest(*CI.getOperand(0)).getNode();
+  if (DisableDirectCallOpt || !isa<Function>(CS.getCalledValue()))
+    Callee = getValueDest(*CS.getCalledValue()).getNode();
 
   std::vector<DSNodeHandle> Args;
-  Args.reserve(CI.getNumOperands()-1);
+  Args.reserve(CS.arg_end()-CS.arg_begin());
 
   // Calculate the arguments vector...
-  for (unsigned i = 1, e = CI.getNumOperands(); i != e; ++i)
-    if (isPointerType(CI.getOperand(i)->getType()))
-      Args.push_back(getValueDest(*CI.getOperand(i)));
+  for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end(); I != E; ++I)
+    if (isPointerType((*I)->getType()))
+      Args.push_back(getValueDest(**I));
 
   // Add a new function call entry...
   if (Callee)
-    FunctionCalls.push_back(DSCallSite(CI, RetVal, Callee, Args));
+    FunctionCalls.push_back(DSCallSite(CS, RetVal, Callee, Args));
   else
-    FunctionCalls.push_back(DSCallSite(CI, RetVal,
-                                       cast<Function>(CI.getOperand(0)), Args));
+    FunctionCalls.push_back(DSCallSite(CS, RetVal, CS.getCalledFunction(),
+                                       Args));
 }
 
 void GraphBuilder::visitFreeInst(FreeInst &FI) {
diff --git a/lib/Analysis/DataStructure/TopDownClosure.cpp b/lib/Analysis/DataStructure/TopDownClosure.cpp
index 92a03ee2f40..13535e3f801 100644
--- a/lib/Analysis/DataStructure/TopDownClosure.cpp
+++ b/lib/Analysis/DataStructure/TopDownClosure.cpp
@@ -96,9 +96,10 @@ void TDDataStructures::ComputePostOrder(Function &F,hash_set<DSGraph*> &Visited,
   const std::vector<DSCallSite> &FunctionCalls = G.getFunctionCalls();
 
   for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i) {
+    Instruction *CallI = FunctionCalls[i].getCallSite().getInstruction();
     std::pair<BUDataStructures::ActualCalleesTy::const_iterator,
       BUDataStructures::ActualCalleesTy::const_iterator>
-         IP = ActualCallees.equal_range(&FunctionCalls[i].getCallInst());
+         IP = ActualCallees.equal_range(CallI);
 
     for (BUDataStructures::ActualCalleesTy::const_iterator I = IP.first;
          I != IP.second; ++I)
@@ -191,10 +192,11 @@ void TDDataStructures::inlineGraphIntoCallees(DSGraph &Graph) {
   // Clone and merge the reachable subgraph from the call into callee's graph.
   // 
   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(&FunctionCalls[i].getCallInst());
+          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
diff --git a/lib/Analysis/IPA/IPModRef.cpp b/lib/Analysis/IPA/IPModRef.cpp
index a90b5c62b02..e7366a0536c 100644
--- a/lib/Analysis/IPA/IPModRef.cpp
+++ b/lib/Analysis/IPA/IPModRef.cpp
@@ -61,7 +61,7 @@ FunctionModRefInfo::FunctionModRefInfo(const Function& func,
 
 FunctionModRefInfo::~FunctionModRefInfo()
 {
-  for(std::map<const CallInst*, ModRefInfo*>::iterator
+  for(std::map<const Instruction*, ModRefInfo*>::iterator
         I=callSiteModRefInfo.begin(), E=callSiteModRefInfo.end(); I != E; ++I)
     delete(I->second);
 
@@ -98,7 +98,7 @@ void FunctionModRefInfo::computeModRef(const Function &func)
   // The call sites are recorded in the TD graph.
   const std::vector<DSCallSite>& callSites = funcTDGraph->getFunctionCalls();
   for (unsigned i = 0, N = callSites.size(); i < N; ++i)
-    computeModRef(callSites[i].getCallInst());
+    computeModRef(callSites[i].getCallSite());
 }
 
 
@@ -117,25 +117,22 @@ void FunctionModRefInfo::computeModRef(const Function &func)
 //       requested information (because the call site calls an external
 //       function or we cannot determine the complete set of functions invoked).
 //
-DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI,
+DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallSite CS,
                                hash_map<const DSNode*, DSNodeHandle> &NodeMap)
 {
   // Step #0: Quick check if we are going to fail anyway: avoid
   // all the graph cloning and map copying in steps #1 and #2.
   // 
-  if (const Function *F = CI.getCalledFunction())
-    {
-      if (F->isExternal())
-        return 0;   // We cannot compute Mod/Ref info for this callsite...
-    }
-  else
-    {
-      // Eventually, should check here if any callee is external.
-      // For now we are not handling this case anyway.
-      std::cerr << "IP Mod/Ref indirect call not implemented yet: "
-              << "Being conservative\n";
+  if (const Function *F = CS.getCalledFunction()) {
+    if (F->isExternal())
       return 0;   // We cannot compute Mod/Ref info for this callsite...
-    }
+  } else {
+    // Eventually, should check here if any callee is external.
+    // For now we are not handling this case anyway.
+    std::cerr << "IP Mod/Ref indirect call not implemented yet: "
+              << "Being conservative\n";
+    return 0;   // We cannot compute Mod/Ref info for this callsite...
+  }
 
   // Step #1: Clone the top-down graph...
   DSGraph *Result = new DSGraph(*funcTDGraph, NodeMap);
@@ -144,7 +141,7 @@ DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI,
   Result->maskNodeTypes(~(DSNode::Modified | DSNode::Read));
 
   // Step #3: clone the bottom up graphs for the callees into the caller graph
-  if (Function *F = CI.getCalledFunction())
+  if (Function *F = CS.getCalledFunction())
     {
       assert(!F->isExternal());
 
@@ -152,17 +149,18 @@ DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI,
 
       // If the call returns a value, make sure to merge the nodes...
       DSNodeHandle RetVal;
-      if (DS::isPointerType(CI.getType()))
-        RetVal = Result->getNodeForValue(&CI);
+      if (DS::isPointerType(CS.getInstruction()->getType()))
+        RetVal = Result->getNodeForValue(CS.getInstruction());
 
       // Populate the arguments list...
       std::vector<DSNodeHandle> Args;
-      for (unsigned i = 1, e = CI.getNumOperands(); i != e; ++i)
-        if (DS::isPointerType(CI.getOperand(i)->getType()))
-          Args.push_back(Result->getNodeForValue(CI.getOperand(i)));
+      for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end();
+           I != E; ++I)
+        if (DS::isPointerType((*I)->getType()))
+          Args.push_back(Result->getNodeForValue(*I));
 
       // Build the call site...
-      DSCallSite CS(CI, RetVal, F, Args);
+      DSCallSite CS(CS, RetVal, F, Args);
 
       // Perform the merging now of the graph for the callee, which will
       // come with mod/ref bits set...
@@ -187,16 +185,15 @@ DSGraph* FunctionModRefInfo::ResolveCallSiteModRefInfo(CallInst &CI,
 // and then inlining the callee's BU graph into the caller's TD graph.
 // 
 void
-FunctionModRefInfo::computeModRef(const CallInst& callInst)
+FunctionModRefInfo::computeModRef(CallSite CS)
 {
   // Allocate the mod/ref info for the call site.  Bits automatically cleared.
   ModRefInfo* callModRefInfo = new ModRefInfo(funcTDGraph->getGraphSize());
-  callSiteModRefInfo[&callInst] = callModRefInfo;
+  callSiteModRefInfo[CS.getInstruction()] = callModRefInfo;
 
   // Get a copy of the graph for the callee with the callee inlined
   hash_map<const DSNode*, DSNodeHandle> NodeMap;
-  DSGraph* csgp = ResolveCallSiteModRefInfo(const_cast<CallInst&>(callInst),
-                                            NodeMap);
+  DSGraph* csgp = ResolveCallSiteModRefInfo(CS, NodeMap);
   if (!csgp)
     { // Callee's side effects are unknown: mark all nodes Mod and Ref.
       // Eventually this should only mark nodes visible to the callee, i.e.,
@@ -323,7 +320,7 @@ void FunctionModRefInfo::print(std::ostream &O) const
 
   // Second: Print Globals and Locals modified at each call site in function
   // 
-  for (std::map<const CallInst*, ModRefInfo*>::const_iterator
+  for (std::map<const Instruction *, ModRefInfo*>::const_iterator
          CI = callSiteModRefInfo.begin(), CE = callSiteModRefInfo.end();
        CI != CE; ++CI)
     {