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diff --git a/contrib/llvm/lib/Analysis/CallGraph.cpp b/contrib/llvm/lib/Analysis/CallGraph.cpp
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+++ b/contrib/llvm/lib/Analysis/CallGraph.cpp
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+//===- CallGraph.cpp - Build a Module's call graph ------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/CallGraph.h"
+#include "llvm/IR/CallSite.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// Implementations of the CallGraph class methods.
+//
+
+CallGraph::CallGraph(Module &M)
+    : M(M), Root(nullptr), ExternalCallingNode(getOrInsertFunction(nullptr)),
+      CallsExternalNode(llvm::make_unique<CallGraphNode>(nullptr)) {
+  // Add every function to the call graph.
+  for (Function &F : M)
+    addToCallGraph(&F);
+
+  // If we didn't find a main function, use the external call graph node
+  if (!Root)
+    Root = ExternalCallingNode;
+}
+
+CallGraph::CallGraph(CallGraph &&Arg)
+    : M(Arg.M), FunctionMap(std::move(Arg.FunctionMap)), Root(Arg.Root),
+      ExternalCallingNode(Arg.ExternalCallingNode),
+      CallsExternalNode(std::move(Arg.CallsExternalNode)) {
+  Arg.FunctionMap.clear();
+  Arg.Root = nullptr;
+  Arg.ExternalCallingNode = nullptr;
+}
+
+CallGraph::~CallGraph() {
+  // CallsExternalNode is not in the function map, delete it explicitly.
+  if (CallsExternalNode)
+    CallsExternalNode->allReferencesDropped();
+
+// Reset all node's use counts to zero before deleting them to prevent an
+// assertion from firing.
+#ifndef NDEBUG
+  for (auto &I : FunctionMap)
+    I.second->allReferencesDropped();
+#endif
+}
+
+void CallGraph::addToCallGraph(Function *F) {
+  CallGraphNode *Node = getOrInsertFunction(F);
+
+  // If this function has external linkage, anything could call it.
+  if (!F->hasLocalLinkage()) {
+    ExternalCallingNode->addCalledFunction(CallSite(), Node);
+
+    // Found the entry point?
+    if (F->getName() == "main") {
+      if (Root) // Found multiple external mains?  Don't pick one.
+        Root = ExternalCallingNode;
+      else
+        Root = Node; // Found a main, keep track of it!
+    }
+  }
+
+  // If this function has its address taken, anything could call it.
+  if (F->hasAddressTaken())
+    ExternalCallingNode->addCalledFunction(CallSite(), Node);
+
+  // If this function is not defined in this translation unit, it could call
+  // anything.
+  if (F->isDeclaration() && !F->isIntrinsic())
+    Node->addCalledFunction(CallSite(), CallsExternalNode.get());
+
+  // Look for calls by this function.
+  for (Function::iterator BB = F->begin(), BBE = F->end(); BB != BBE; ++BB)
+    for (BasicBlock::iterator II = BB->begin(), IE = BB->end(); II != IE;
+         ++II) {
+      CallSite CS(cast<Value>(II));
+      if (CS) {
+        const Function *Callee = CS.getCalledFunction();
+        if (!Callee || !Intrinsic::isLeaf(Callee->getIntrinsicID()))
+          // Indirect calls of intrinsics are not allowed so no need to check.
+          // We can be more precise here by using TargetArg returned by
+          // Intrinsic::isLeaf.
+          Node->addCalledFunction(CS, CallsExternalNode.get());
+        else if (!Callee->isIntrinsic())
+          Node->addCalledFunction(CS, getOrInsertFunction(Callee));
+      }
+    }
+}
+
+void CallGraph::print(raw_ostream &OS) const {
+  OS << "CallGraph Root is: ";
+  if (Function *F = Root->getFunction())
+    OS << F->getName() << "\n";
+  else {
+    OS << "<<null function: 0x" << Root << ">>\n";
+  }
+
+  // Print in a deterministic order by sorting CallGraphNodes by name.  We do
+  // this here to avoid slowing down the non-printing fast path.
+
+  SmallVector<CallGraphNode *, 16> Nodes;
+  Nodes.reserve(FunctionMap.size());
+
+  for (auto I = begin(), E = end(); I != E; ++I)
+    Nodes.push_back(I->second.get());
+
+  std::sort(Nodes.begin(), Nodes.end(),
+            [](CallGraphNode *LHS, CallGraphNode *RHS) {
+    if (Function *LF = LHS->getFunction())
+      if (Function *RF = RHS->getFunction())
+        return LF->getName() < RF->getName();
+
+    return RHS->getFunction() != nullptr;
+  });
+
+  for (CallGraphNode *CN : Nodes)
+    CN->print(OS);
+}
+
+LLVM_DUMP_METHOD
+void CallGraph::dump() const { print(dbgs()); }
+
+// removeFunctionFromModule - Unlink the function from this module, returning
+// it.  Because this removes the function from the module, the call graph node
+// is destroyed.  This is only valid if the function does not call any other
+// functions (ie, there are no edges in it's CGN).  The easiest way to do this
+// is to dropAllReferences before calling this.
+//
+Function *CallGraph::removeFunctionFromModule(CallGraphNode *CGN) {
+  assert(CGN->empty() && "Cannot remove function from call "
+         "graph if it references other functions!");
+  Function *F = CGN->getFunction(); // Get the function for the call graph node
+  FunctionMap.erase(F);             // Remove the call graph node from the map
+
+  M.getFunctionList().remove(F);
+  return F;
+}
+
+/// spliceFunction - Replace the function represented by this node by another.
+/// This does not rescan the body of the function, so it is suitable when
+/// splicing the body of the old function to the new while also updating all
+/// callers from old to new.
+///
+void CallGraph::spliceFunction(const Function *From, const Function *To) {
+  assert(FunctionMap.count(From) && "No CallGraphNode for function!");
+  assert(!FunctionMap.count(To) &&
+         "Pointing CallGraphNode at a function that already exists");
+  FunctionMapTy::iterator I = FunctionMap.find(From);
+  I->second->F = const_cast<Function*>(To);
+  FunctionMap[To] = std::move(I->second);
+  FunctionMap.erase(I);
+}
+
+// getOrInsertFunction - This method is identical to calling operator[], but
+// it will insert a new CallGraphNode for the specified function if one does
+// not already exist.
+CallGraphNode *CallGraph::getOrInsertFunction(const Function *F) {
+  auto &CGN = FunctionMap[F];
+  if (CGN)
+    return CGN.get();
+
+  assert((!F || F->getParent() == &M) && "Function not in current module!");
+  CGN = llvm::make_unique<CallGraphNode>(const_cast<Function *>(F));
+  return CGN.get();
+}
+
+//===----------------------------------------------------------------------===//
+// Implementations of the CallGraphNode class methods.
+//
+
+void CallGraphNode::print(raw_ostream &OS) const {
+  if (Function *F = getFunction())
+    OS << "Call graph node for function: '" << F->getName() << "'";
+  else
+    OS << "Call graph node <<null function>>";
+  
+  OS << "<<" << this << ">>  #uses=" << getNumReferences() << '\n';
+
+  for (const_iterator I = begin(), E = end(); I != E; ++I) {
+    OS << "  CS<" << I->first << "> calls ";
+    if (Function *FI = I->second->getFunction())
+      OS << "function '" << FI->getName() <<"'\n";
+    else
+      OS << "external node\n";
+  }
+  OS << '\n';
+}
+
+LLVM_DUMP_METHOD
+void CallGraphNode::dump() const { print(dbgs()); }
+
+/// removeCallEdgeFor - This method removes the edge in the node for the
+/// specified call site.  Note that this method takes linear time, so it
+/// should be used sparingly.
+void CallGraphNode::removeCallEdgeFor(CallSite CS) {
+  for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) {
+    assert(I != CalledFunctions.end() && "Cannot find callsite to remove!");
+    if (I->first == CS.getInstruction()) {
+      I->second->DropRef();
+      *I = CalledFunctions.back();
+      CalledFunctions.pop_back();
+      return;
+    }
+  }
+}
+
+// removeAnyCallEdgeTo - This method removes any call edges from this node to
+// the specified callee function.  This takes more time to execute than
+// removeCallEdgeTo, so it should not be used unless necessary.
+void CallGraphNode::removeAnyCallEdgeTo(CallGraphNode *Callee) {
+  for (unsigned i = 0, e = CalledFunctions.size(); i != e; ++i)
+    if (CalledFunctions[i].second == Callee) {
+      Callee->DropRef();
+      CalledFunctions[i] = CalledFunctions.back();
+      CalledFunctions.pop_back();
+      --i; --e;
+    }
+}
+
+/// removeOneAbstractEdgeTo - Remove one edge associated with a null callsite
+/// from this node to the specified callee function.
+void CallGraphNode::removeOneAbstractEdgeTo(CallGraphNode *Callee) {
+  for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) {
+    assert(I != CalledFunctions.end() && "Cannot find callee to remove!");
+    CallRecord &CR = *I;
+    if (CR.second == Callee && CR.first == nullptr) {
+      Callee->DropRef();
+      *I = CalledFunctions.back();
+      CalledFunctions.pop_back();
+      return;
+    }
+  }
+}
+
+/// replaceCallEdge - This method replaces the edge in the node for the
+/// specified call site with a new one.  Note that this method takes linear
+/// time, so it should be used sparingly.
+void CallGraphNode::replaceCallEdge(CallSite CS,
+                                    CallSite NewCS, CallGraphNode *NewNode){
+  for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) {
+    assert(I != CalledFunctions.end() && "Cannot find callsite to remove!");
+    if (I->first == CS.getInstruction()) {
+      I->second->DropRef();
+      I->first = NewCS.getInstruction();
+      I->second = NewNode;
+      NewNode->AddRef();
+      return;
+    }
+  }
+}
+
+//===----------------------------------------------------------------------===//
+// Out-of-line definitions of CallGraphAnalysis class members.
+//
+
+char CallGraphAnalysis::PassID;
+
+//===----------------------------------------------------------------------===//
+// Implementations of the CallGraphWrapperPass class methods.
+//
+
+CallGraphWrapperPass::CallGraphWrapperPass() : ModulePass(ID) {
+  initializeCallGraphWrapperPassPass(*PassRegistry::getPassRegistry());
+}
+
+CallGraphWrapperPass::~CallGraphWrapperPass() {}
+
+void CallGraphWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+}
+
+bool CallGraphWrapperPass::runOnModule(Module &M) {
+  // All the real work is done in the constructor for the CallGraph.
+  G.reset(new CallGraph(M));
+  return false;
+}
+
+INITIALIZE_PASS(CallGraphWrapperPass, "basiccg", "CallGraph Construction",
+                false, true)
+
+char CallGraphWrapperPass::ID = 0;
+
+void CallGraphWrapperPass::releaseMemory() { G.reset(); }
+
+void CallGraphWrapperPass::print(raw_ostream &OS, const Module *) const {
+  if (!G) {
+    OS << "No call graph has been built!\n";
+    return;
+  }
+
+  // Just delegate.
+  G->print(OS);
+}
+
+LLVM_DUMP_METHOD
+void CallGraphWrapperPass::dump() const { print(dbgs(), nullptr); }