X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FIPA%2FCallGraph.cpp;h=5f9850c93dcbff08dd43d71558e6eed0fec6971a;hb=1997473cf72957d0e70322e2fe6fe2ab141c58a6;hp=8d660b99fb3525942fa5293b974984a9c1338ba8;hpb=b81c021f14107b12d1275c84fbce170db06437a5;p=oota-llvm.git diff --git a/lib/Analysis/IPA/CallGraph.cpp b/lib/Analysis/IPA/CallGraph.cpp index 8d660b99fb3..5f9850c93dc 100644 --- a/lib/Analysis/IPA/CallGraph.cpp +++ b/lib/Analysis/IPA/CallGraph.cpp @@ -1,38 +1,29 @@ //===- CallGraph.cpp - Build a Module's call graph ------------------------===// -// +// // The LLVM Compiler Infrastructure // // This file was developed by the LLVM research group and is distributed under // the University of Illinois Open Source License. See LICENSE.TXT for details. -// +// //===----------------------------------------------------------------------===// // -// This file implements the CallGraph class. +// This file implements the CallGraph class and provides the BasicCallGraph +// default implementation. // //===----------------------------------------------------------------------===// #include "llvm/Analysis/CallGraph.h" -#include "llvm/Constants.h" // Remove when ConstantPointerRefs are gone #include "llvm/Module.h" -#include "llvm/iOther.h" -#include "llvm/iTerminators.h" +#include "llvm/Instructions.h" #include "llvm/Support/CallSite.h" -#include "Support/STLExtras.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/Streams.h" +#include using namespace llvm; -static RegisterAnalysis X("callgraph", "Call Graph Construction"); - -// getNodeFor - Return the node for the specified function or create one if it -// does not already exist. -// -CallGraphNode *CallGraph::getNodeFor(Function *F) { - CallGraphNode *&CGN = FunctionMap[F]; - if (CGN) return CGN; - - assert((!F || F->getParent() == Mod) && "Function not in current module!"); - return CGN = new CallGraphNode(F); -} - +/// isOnlyADirectCall - Return true if this callsite is *just* a direct call to +/// the specified function. Specifically return false if the callsite also +/// takes the address of the function. static bool isOnlyADirectCall(Function *F, CallSite CS) { if (!CS.getInstruction()) return false; for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end(); I != E; ++I) @@ -40,132 +31,200 @@ static bool isOnlyADirectCall(Function *F, CallSite CS) { return true; } -// addToCallGraph - Add a function to the call graph, and link the node to all -// of the functions that it calls. +namespace { + +//===----------------------------------------------------------------------===// +// BasicCallGraph class definition // -void CallGraph::addToCallGraph(Function *F) { - CallGraphNode *Node = getNodeFor(F); - - // If this function has external linkage, anything could call it... - if (!F->hasInternalLinkage()) { - ExternalCallingNode->addCalledFunction(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! - } +class VISIBILITY_HIDDEN BasicCallGraph : public CallGraph, public ModulePass { + // 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((intptr_t)&ID), Root(0), + ExternalCallingNode(0), CallsExternalNode(0) {} + + // 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(); + } + + void print(std::ostream *o, const Module *M) const { + if (o) print(*o, M); + } + + virtual void print(std::ostream &o, const Module *M) const { + o << "CallGraph Root is: "; + if (Function *F = getRoot()->getFunction()) + o << F->getName() << "\n"; + else + o << "<>\n"; + + CallGraph::print(o, M); + } + + virtual void releaseMemory() { + destroy(); } - // If this function is not defined in this translation unit, it could call - // anything. - if (F->isExternal() && !F->getIntrinsicID()) - Node->addCalledFunction(CallsExternalNode); + /// dump - Print out this call graph. + /// + inline void dump() const { + print(cerr, Mod); + } - // Loop over all of the users of the function... looking for callers... + 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. // - bool isUsedExternally = false; - for (Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E; ++I) { - if (Instruction *Inst = dyn_cast(*I)) { - if (isOnlyADirectCall(F, CallSite::get(Inst))) - getNodeFor(Inst->getParent()->getParent())->addCalledFunction(Node); - else - isUsedExternally = true; - } else if (ConstantPointerRef *CPR = dyn_cast(*I)) { - // THIS IS A DISGUSTING HACK. Brought to you by the power of - // ConstantPointerRefs! - for (Value::use_iterator I = CPR->use_begin(), E = CPR->use_end(); - I != E; ++I) - if (Instruction *Inst = dyn_cast(*I)) { - if (isOnlyADirectCall(F, CallSite::get(Inst))) - getNodeFor(Inst->getParent()->getParent())->addCalledFunction(Node); - else - isUsedExternally = true; - } else { + 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->hasInternalLinkage()) { + 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 is not defined in this translation unit, it could call + // anything. + if (F->isDeclaration() && !F->getIntrinsicID()) + Node->addCalledFunction(CallSite(), CallsExternalNode); + + // Loop over all of the users of the function... looking for callers... + // + bool isUsedExternally = false; + for (Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E; ++I){ + if (Instruction *Inst = dyn_cast(*I)) { + CallSite CS = CallSite::get(Inst); + if (isOnlyADirectCall(F, CS)) + getOrInsertFunction(Inst->getParent()->getParent()) + ->addCalledFunction(CS, Node); + else isUsedExternally = true; - } - } else { // Can't classify the user! - isUsedExternally = true; + } else if (GlobalValue *GV = dyn_cast(*I)) { + for (Value::use_iterator I = GV->use_begin(), E = GV->use_end(); + I != E; ++I) + if (Instruction *Inst = dyn_cast(*I)) { + CallSite CS = CallSite::get(Inst); + if (isOnlyADirectCall(F, CS)) + getOrInsertFunction(Inst->getParent()->getParent()) + ->addCalledFunction(CS, Node); + else + isUsedExternally = true; + } else { + isUsedExternally = true; + } + } else { // Can't classify the user! + isUsedExternally = true; + } } - } - if (isUsedExternally) - ExternalCallingNode->addCalledFunction(Node); + if (isUsedExternally) + ExternalCallingNode->addCalledFunction(CallSite(), Node); - // Look for an indirect function call... - for (Function::iterator BB = F->begin(), BBE = F->end(); BB != BBE; ++BB) - for (BasicBlock::iterator II = BB->begin(), IE = BB->end(); II != IE; ++II){ + // Look for an indirect function call. + 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 = CallSite::get(II); if (CS.getInstruction() && !CS.getCalledFunction()) - Node->addCalledFunction(CallsExternalNode); - } -} + Node->addCalledFunction(CS, CallsExternalNode); + } + } -bool CallGraph::run(Module &M) { - destroy(); + // + // destroy - Release memory for the call graph + virtual void destroy() { + /// CallsExternalNode is not in the function map, delete it explicitly. + delete CallsExternalNode; + CallsExternalNode = 0; + CallGraph::destroy(); + } +}; - Mod = &M; - ExternalCallingNode = getNodeFor(0); - CallsExternalNode = new CallGraphNode(0); - Root = 0; +RegisterAnalysisGroup X("Call Graph"); +RegisterPass Y("basiccg", "Basic CallGraph Construction"); +RegisterAnalysisGroup Z(Y); - // Add every function to the call graph... - for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) - addToCallGraph(I); +} //End anonymous namespace - // If we didn't find a main function, use the external call graph node - if (Root == 0) Root = ExternalCallingNode; - - return false; -} +char CallGraph::ID = 0; +char BasicCallGraph::ID = 0; -void CallGraph::destroy() { - for (FunctionMapTy::iterator I = FunctionMap.begin(), E = FunctionMap.end(); - I != E; ++I) - delete I->second; - FunctionMap.clear(); +void CallGraph::initialize(Module &M) { + Mod = &M; } -static void WriteToOutput(const CallGraphNode *CGN, std::ostream &o) { - if (CGN->getFunction()) - o << "Call graph node for function: '" - << CGN->getFunction()->getName() <<"'\n"; - else - o << "Call graph node <>:\n"; - - for (unsigned i = 0; i < CGN->size(); ++i) - if ((*CGN)[i]->getFunction()) - o << " Calls function '" << (*CGN)[i]->getFunction()->getName() << "'\n"; - else - o << " Calls external node\n"; - o << "\n"; +void CallGraph::destroy() { + if (!FunctionMap.empty()) { + for (FunctionMapTy::iterator I = FunctionMap.begin(), E = FunctionMap.end(); + I != E; ++I) + delete I->second; + FunctionMap.clear(); + } } -void CallGraph::print(std::ostream &o, const Module *M) const { - o << "CallGraph Root is: "; - if (getRoot()->getFunction()) - o << getRoot()->getFunction()->getName() << "\n"; - else - o << "<>\n"; - +void CallGraph::print(std::ostream &OS, const Module *M) const { for (CallGraph::const_iterator I = begin(), E = end(); I != E; ++I) - WriteToOutput(I->second, o); + I->second->print(OS); } +void CallGraph::dump() const { + print(cerr, 0); +} //===----------------------------------------------------------------------===// // Implementations of public modification methods // -// Functions to keep a call graph up to date with a function that has been -// modified -// -void CallGraph::addFunctionToModule(Function *F) { - assert(0 && "not implemented"); - abort(); -} - // 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 @@ -183,14 +242,68 @@ Function *CallGraph::removeFunctionFromModule(CallGraphNode *CGN) { return F; } -void CallGraph::stub() {} +// changeFunction - This method changes the function associated with this +// CallGraphNode, for use by transformations that need to change the prototype +// of a Function (thus they must create a new Function and move the old code +// over). +void CallGraph::changeFunction(Function *OldF, Function *NewF) { + iterator I = FunctionMap.find(OldF); + CallGraphNode *&New = FunctionMap[NewF]; + assert(I != FunctionMap.end() && I->second && !New && + "OldF didn't exist in CG or NewF already does!"); + New = I->second; + New->F = NewF; + 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) { + CallGraphNode *&CGN = FunctionMap[F]; + if (CGN) return CGN; + + assert((!F || F->getParent() == Mod) && "Function not in current module!"); + return CGN = new CallGraphNode(const_cast(F)); +} + +void CallGraphNode::print(std::ostream &OS) const { + if (Function *F = getFunction()) + OS << "Call graph node for function: '" << F->getName() <<"'\n"; + else + OS << "Call graph node <>:\n"; + + for (const_iterator I = begin(), E = end(); I != E; ++I) + if (I->second->getFunction()) + OS << " Calls function '" << I->second->getFunction()->getName() <<"'\n"; + else + OS << " Calls external node\n"; + OS << "\n"; +} + +void CallGraphNode::dump() const { print(cerr); } void CallGraphNode::removeCallEdgeTo(CallGraphNode *Callee) { for (unsigned i = CalledFunctions.size(); ; --i) { assert(i && "Cannot find callee to remove!"); - if (CalledFunctions[i-1] == Callee) { + if (CalledFunctions[i-1].second == Callee) { CalledFunctions.erase(CalledFunctions.begin()+i-1); 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) { + CalledFunctions[i] = CalledFunctions.back(); + CalledFunctions.pop_back(); + --i; --e; + } +} + +// Enuse that users of CallGraph.h also link with this file +DEFINING_FILE_FOR(CallGraph)