-class BasicCallGraph : public ModulePass, public CallGraph {
- // Root is root of the call graph, or the external node if a 'main' function
- // couldn't be found.
- //
- CallGraphNode *Root;
-
- // ExternalCallingNode - This node has edges to all external functions and
- // those internal functions that have their address taken.
- CallGraphNode *ExternalCallingNode;
-
- // CallsExternalNode - This node has edges to it from all functions making
- // indirect calls or calling an external function.
- CallGraphNode *CallsExternalNode;
-
-public:
- static char ID; // Class identification, replacement for typeinfo
- BasicCallGraph() : ModulePass(ID), Root(0),
- ExternalCallingNode(0), CallsExternalNode(0) {
- initializeBasicCallGraphPass(*PassRegistry::getPassRegistry());
- }
-
- // runOnModule - Compute the call graph for the specified module.
- virtual bool runOnModule(Module &M) {
- CallGraph::initialize(M);
-
- ExternalCallingNode = getOrInsertFunction(0);
- CallsExternalNode = new CallGraphNode(0);
- Root = 0;
-
- // Add every function to the call graph.
- for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
- addToCallGraph(I);
-
- // If we didn't find a main function, use the external call graph node
- if (Root == 0) Root = ExternalCallingNode;
-
- return false;
- }
-
- virtual void getAnalysisUsage(AnalysisUsage &AU) const {
- AU.setPreservesAll();
- }
-
- virtual void print(raw_ostream &OS, const Module *) const {
- OS << "CallGraph Root is: ";
- if (Function *F = getRoot()->getFunction())
- OS << F->getName() << "\n";
- else {
- OS << "<<null function: 0x" << getRoot() << ">>\n";
- }
-
- CallGraph::print(OS, 0);
- }
-
- virtual void releaseMemory() {
- destroy();
- }
-
- /// getAdjustedAnalysisPointer - This method is used when a pass implements
- /// an analysis interface through multiple inheritance. If needed, it should
- /// override this to adjust the this pointer as needed for the specified pass
- /// info.
- virtual void *getAdjustedAnalysisPointer(AnalysisID PI) {
- if (PI == &CallGraph::ID)
- return (CallGraph*)this;
- return this;
- }
-
- CallGraphNode* getExternalCallingNode() const { return ExternalCallingNode; }
- CallGraphNode* getCallsExternalNode() const { return CallsExternalNode; }
-
- // getRoot - Return the root of the call graph, which is either main, or if
- // main cannot be found, the external node.
- //
- CallGraphNode *getRoot() { return Root; }
- const CallGraphNode *getRoot() const { return Root; }
-
-private:
- //===---------------------------------------------------------------------
- // Implementation of CallGraph construction
- //
-
- // addToCallGraph - Add a function to the call graph, and link the node to all
- // of the functions that it calls.
- //
- void 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);
-
- // 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 && !isa<IntrinsicInst>(II)) {
- const Function *Callee = CS.getCalledFunction();
- if (Callee)
- Node->addCalledFunction(CS, getOrInsertFunction(Callee));
- else
- Node->addCalledFunction(CS, CallsExternalNode);
- }
- }
- }
-
- //
- // destroy - Release memory for the call graph
- virtual void destroy() {
- /// CallsExternalNode is not in the function map, delete it explicitly.
- if (CallsExternalNode) {
- CallsExternalNode->allReferencesDropped();
- delete CallsExternalNode;
- CallsExternalNode = 0;
- }
- CallGraph::destroy();
- }
-};
-
-} //End anonymous namespace
-
-INITIALIZE_ANALYSIS_GROUP(CallGraph, "Call Graph", BasicCallGraph)
-INITIALIZE_AG_PASS(BasicCallGraph, CallGraph, "basiccg",
- "Basic CallGraph Construction", false, true, true)