/// removeDeadFunctions - Remove dead functions that are not included in /// DNR (Do Not Remove) list. bool Inliner::removeDeadFunctions(CallGraph &CG, bool AlwaysInlineOnly) { SmallVector<CallGraphNode*, 16> FunctionsToRemove; // Scan for all of the functions, looking for ones that should now be removed // from the program. Insert the dead ones in the FunctionsToRemove set. for (CallGraph::iterator I = CG.begin(), E = CG.end(); I != E; ++I) { CallGraphNode *CGN = I->second; Function *F = CGN->getFunction(); if (!F || F->isDeclaration()) continue; // Handle the case when this function is called and we only want to care // about always-inline functions. This is a bit of a hack to share code // between here and the InlineAlways pass. if (AlwaysInlineOnly && !F->getFnAttributes().hasAttribute(Attribute::AlwaysInline)) continue; // If the only remaining users of the function are dead constants, remove // them. F->removeDeadConstantUsers(); if (!F->isDefTriviallyDead()) continue; // Remove any call graph edges from the function to its callees. CGN->removeAllCalledFunctions(); // Remove any edges from the external node to the function's call graph // node. These edges might have been made irrelegant due to // optimization of the program. CG.getExternalCallingNode()->removeAnyCallEdgeTo(CGN); // Removing the node for callee from the call graph and delete it. FunctionsToRemove.push_back(CGN); } if (FunctionsToRemove.empty()) return false; // Now that we know which functions to delete, do so. We didn't want to do // this inline, because that would invalidate our CallGraph::iterator // objects. :( // // Note that it doesn't matter that we are iterating over a non-stable order // here to do this, it doesn't matter which order the functions are deleted // in. array_pod_sort(FunctionsToRemove.begin(), FunctionsToRemove.end()); FunctionsToRemove.erase(std::unique(FunctionsToRemove.begin(), FunctionsToRemove.end()), FunctionsToRemove.end()); for (SmallVectorImpl<CallGraphNode *>::iterator I = FunctionsToRemove.begin(), E = FunctionsToRemove.end(); I != E; ++I) { delete CG.removeFunctionFromModule(*I); ++NumDeleted; } return true; }
/// removeDeadFunctions - Remove dead functions that are not included in /// DNR (Do Not Remove) list. bool Inliner::removeDeadFunctions(CallGraph &CG, SmallPtrSet<const Function *, 16> *DNR) { SmallPtrSet<CallGraphNode*, 16> FunctionsToRemove; // Scan for all of the functions, looking for ones that should now be removed // from the program. Insert the dead ones in the FunctionsToRemove set. for (CallGraph::iterator I = CG.begin(), E = CG.end(); I != E; ++I) { CallGraphNode *CGN = I->second; if (CGN->getFunction() == 0) continue; Function *F = CGN->getFunction(); // If the only remaining users of the function are dead constants, remove // them. F->removeDeadConstantUsers(); if (DNR && DNR->count(F)) continue; if (!F->hasLinkOnceLinkage() && !F->hasLocalLinkage() && !F->hasAvailableExternallyLinkage()) continue; if (!F->use_empty()) continue; // Remove any call graph edges from the function to its callees. CGN->removeAllCalledFunctions(); // Remove any edges from the external node to the function's call graph // node. These edges might have been made irrelegant due to // optimization of the program. CG.getExternalCallingNode()->removeAnyCallEdgeTo(CGN); // Removing the node for callee from the call graph and delete it. FunctionsToRemove.insert(CGN); } // Now that we know which functions to delete, do so. We didn't want to do // this inline, because that would invalidate our CallGraph::iterator // objects. :( // // Note that it doesn't matter that we are iterating over a non-stable set // here to do this, it doesn't matter which order the functions are deleted // in. bool Changed = false; for (SmallPtrSet<CallGraphNode*, 16>::iterator I = FunctionsToRemove.begin(), E = FunctionsToRemove.end(); I != E; ++I) { resetCachedCostInfo((*I)->getFunction()); delete CG.removeFunctionFromModule(*I); ++NumDeleted; Changed = true; } return Changed; }
void AnalysisConsumer::HandleDeclsCallGraph(const unsigned LocalTUDeclsSize) { // Build the Call Graph by adding all the top level declarations to the graph. // Note: CallGraph can trigger deserialization of more items from a pch // (though HandleInterestingDecl); triggering additions to LocalTUDecls. // We rely on random access to add the initially processed Decls to CG. CallGraph CG; for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) { CG.addToCallGraph(LocalTUDecls[i]); } // Walk over all of the call graph nodes in topological order, so that we // analyze parents before the children. Skip the functions inlined into // the previously processed functions. Use external Visited set to identify // inlined functions. The topological order allows the "do not reanalyze // previously inlined function" performance heuristic to be triggered more // often. SetOfConstDecls Visited; SetOfConstDecls VisitedAsTopLevel; llvm::ReversePostOrderTraversal<clang::CallGraph*> RPOT(&CG); for (llvm::ReversePostOrderTraversal<clang::CallGraph*>::rpo_iterator I = RPOT.begin(), E = RPOT.end(); I != E; ++I) { NumFunctionTopLevel++; CallGraphNode *N = *I; Decl *D = N->getDecl(); string ssStart = D->getLocStart().printToString(Mgr->getASTContext().getSourceManager()); // Skip the abstract root node. if (!D) continue; // Skip the functions which have been processed already or previously // inlined. if (shouldSkipFunction(D, Visited, VisitedAsTopLevel)) continue; // Analyze the function. SetOfConstDecls VisitedCallees; HandleCode(D, AM_Path, (Mgr->options.InliningMode == All ? nullptr : &VisitedCallees)); // Add the visited callees to the global visited set. for (SetOfConstDecls::iterator I = VisitedCallees.begin(), E = VisitedCallees.end(); I != E; ++I) { Visited.insert(*I); } VisitedAsTopLevel.insert(D); } }
// FIXME: This code is stolen from CallGraph::addToCallGraph(Function *F), which // happens to be private. It is better for this functionality exposed by the // CallGraph. static void buildCGN(CallGraph &CG, CallGraphNode *Node) { Function *F = Node->getFunction(); // Look for calls by this function. for (Instruction &I : instructions(F)) if (CallSite CS = CallSite(cast<Value>(&I))) { 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, CG.getCallsExternalNode()); else if (!Callee->isIntrinsic()) Node->addCalledFunction(CS, CG.getOrInsertFunction(Callee)); } }
// InlineCallIfPossible - If it is possible to inline the specified call site, // do so and update the CallGraph for this operation. static bool InlineCallIfPossible(CallSite CS, CallGraph &CG, const std::set<Function*> &SCCFunctions, const TargetData &TD) { Function *Callee = CS.getCalledFunction(); Function *Caller = CS.getCaller(); if (!InlineFunction(CS, &CG, &TD)) return false; // If the inlined function had a higher stack protection level than the // calling function, then bump up the caller's stack protection level. if (Callee->hasFnAttr(Attribute::StackProtectReq)) Caller->addFnAttr(Attribute::StackProtectReq); else if (Callee->hasFnAttr(Attribute::StackProtect) && !Caller->hasFnAttr(Attribute::StackProtectReq)) Caller->addFnAttr(Attribute::StackProtect); // If we inlined the last possible call site to the function, delete the // function body now. if (Callee->use_empty() && Callee->hasLocalLinkage() && !SCCFunctions.count(Callee)) { DOUT << " -> Deleting dead function: " << Callee->getName() << "\n"; CallGraphNode *CalleeNode = CG[Callee]; // Remove any call graph edges from the callee to its callees. CalleeNode->removeAllCalledFunctions(); // Removing the node for callee from the call graph and delete it. delete CG.removeFunctionFromModule(CalleeNode); ++NumDeleted; } return true; }
bool PrintCgTree::runOnModule(Module &M) { #if LLVM_VERSION_MAJOR == 3 && LLVM_VERSION_MINOR == 4 CallGraph CG; CG.runOnModule(M); CallGraphNode* root = CG.getRoot(); #else CallGraph CG(M); Function* Main = M.getFunction("main"); CallGraphNode* root = Main?CG[Main]:CG.getExternalCallingNode(); #endif Assert(root->getFunction()==Main, ""); errs()<<root->getFunction()->getName()<<"\n"; print_cg(root); return false; }
std::vector<Error> Recursivity::check(const super_ast::Block* ast, std::vector<struct RecursivityCheck> checks) { FunctionIds fids; ast->Accept(fids); std::map<std::string, struct FunctionInfo> ids = fids.get_ids(); CallGraph cg; cg.set_ids(ids); ast->Accept(cg); call_graph_ = cg.get_graph(); call_count_ = cg.get_num_calls(); call_count_.resize(call_graph_.size()); std::vector<int> recursivity = get_recursivity(); //for (int i = 0; i < call_graph_.size(); ++i) { // std::cout << "[" << i << "] "; // for (int j = 0; j < call_graph_[i].size(); ++j) { // std::cout << " " << call_graph_[i][j]; // } // std::cout << std::endl; //} //for (int i = 0; i < recursivity.size(); ++i) { // std::cout << "[" << i << "] " << recursivity[i] << std::endl; //} //Error checking std::vector<Error> errors; for (struct RecursivityCheck c : checks) { struct FunctionInfo finf = ids[c.signature]; if (c.depth != -1 and recursivity[finf.id] != c.depth) { // Error encountered std::ostringstream ss; ss << "expected depth " << c.depth << " found " << recursivity[finf.id]; std::string detail = ss.str(); struct Error e(finf.line, c.signature, "RECURSIVITY ERROR", detail); errors.push_back(e); } } return errors; }
// doInitialization - Initializes the vector of functions that have not // been annotated with the "always inline" attribute. bool AlwaysInliner::doInitialization(CallGraph &CG) { Module &M = CG.getModule(); for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) if (!I->isDeclaration() && !I->hasFnAttr(Attribute::AlwaysInline)) NeverInline.insert(I); return false; }
// doFinalization - Remove now-dead linkonce functions at the end of // processing to avoid breaking the SCC traversal. bool Inliner::doFinalization(CallGraph &CG) { std::set<CallGraphNode*> FunctionsToRemove; // Scan for all of the functions, looking for ones that should now be removed // from the program. Insert the dead ones in the FunctionsToRemove set. for (CallGraph::iterator I = CG.begin(), E = CG.end(); I != E; ++I) { CallGraphNode *CGN = I->second; if (Function *F = CGN ? CGN->getFunction() : 0) { // If the only remaining users of the function are dead constants, remove // them. F->removeDeadConstantUsers(); if ((F->hasLinkOnceLinkage() || F->hasInternalLinkage()) && F->use_empty()) { // Remove any call graph edges from the function to its callees. while (!CGN->empty()) CGN->removeCallEdgeTo((CGN->end()-1)->second); // Remove any edges from the external node to the function's call graph // node. These edges might have been made irrelegant due to // optimization of the program. CG.getExternalCallingNode()->removeAnyCallEdgeTo(CGN); // Removing the node for callee from the call graph and delete it. FunctionsToRemove.insert(CGN); } } } // Now that we know which functions to delete, do so. We didn't want to do // this inline, because that would invalidate our CallGraph::iterator // objects. :( bool Changed = false; for (std::set<CallGraphNode*>::iterator I = FunctionsToRemove.begin(), E = FunctionsToRemove.end(); I != E; ++I) { delete CG.removeFunctionFromModule(*I); ++NumDeleted; Changed = true; } return Changed; }
// Make sure that there is a devirtualization trigger function that CoroSplit // pass uses the force restart CGSCC pipeline. If devirt trigger function is not // found, we will create one and add it to the current SCC. static void createDevirtTriggerFunc(CallGraph &CG, CallGraphSCC &SCC) { Module &M = CG.getModule(); if (M.getFunction(CORO_DEVIRT_TRIGGER_FN)) return; LLVMContext &C = M.getContext(); auto *FnTy = FunctionType::get(Type::getVoidTy(C), Type::getInt8PtrTy(C), /*IsVarArgs=*/false); Function *DevirtFn = Function::Create(FnTy, GlobalValue::LinkageTypes::PrivateLinkage, CORO_DEVIRT_TRIGGER_FN, &M); DevirtFn->addFnAttr(Attribute::AlwaysInline); auto *Entry = BasicBlock::Create(C, "entry", DevirtFn); ReturnInst::Create(C, Entry); auto *Node = CG.getOrInsertFunction(DevirtFn); SmallVector<CallGraphNode *, 8> Nodes(SCC.begin(), SCC.end()); Nodes.push_back(Node); SCC.initialize(Nodes); }
void benchAnalyzingEdges(CallGraph& graph) { Infos infos; Analyzer analyzer(graph, infos); Timer timer; CallSiteIterator cit, cend; for (boost::tie(cit, cend) = graph.callSites(); cit != cend; ++cit) { analyzer.computeCallSiteTemperature(*cit); } analyzeEdges += timer.elapsed(); }
void benchAnalyzingVertices(CallGraph& graph) { Infos infos; Analyzer analyzer(graph, infos); Timer timer; FunctionIterator fit, fend; for (boost::tie(fit, fend) = graph.functions(); fit != fend; ++fit) { analyzer.computeFunctionTemperature(*fit); } analyzeVertices += timer.elapsed(); }
bool CallGraphCFG::runOnModule(Module &M) { CallGraph *CG = &getAnalysis<CallGraph>(); CallGraphNode *root = CG->getRoot(); if (root == NULL) return true; getDefectList(defectFile, &dl); if (dl.size()==0) return true; for (defectList::iterator dit=dl.begin(); dit != dl.end(); ++dit) { std::string file = dit->first; std::vector<int> lines = dit->second; for (std::vector<int>::iterator lit=lines.begin(); lit != lines.end(); ++lit) { std::cerr << "Mapping defect to BBs " << file << ":" << *lit << "\n"; std::vector<BasicBlock*> tpath; findBBPath(root, tpath, file, *lit); if (tpath.size() == 0) std::cerr << "! unreachable " << file << ":" << *lit << "\n"; else bbpaths->push_back(tpath); } } return false; }
void benchForeachEdges(const CallGraph& graph) { double sum = 0; Timer timer; CallSiteIterator first, last; for (boost::tie(first, last) = graph.callSites(); first != last; ++first) { sum += graph[*first].temperature; } foreachEdges += timer.elapsed(); fakeSum += sum; }
/// Finalize CG bool CGPassManager::doFinalization(CallGraph &CG) { bool Changed = false; for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) { Pass *P = getContainedPass(Index); if (CallGraphSCCPass *CGSP = dynamic_cast<CallGraphSCCPass *>(P)) { Changed |= CGSP->doFinalization(CG); } else { FPPassManager *FP = dynamic_cast<FPPassManager *>(P); assert (FP && "Invalid CGPassManager member"); Changed |= FP->doFinalization(CG.getModule()); } } return Changed; }
pdvector<const resource*> MagnifyManager::getChildren(const resource *rh, magnifyType type) { pdvector<const resource*> ret; if(type == OriginalSearch) { ret = rh->getChildren(); } else { assert(type == CallGraphSearch); //It doesn't make sense to expand the call graph down all of //the resource hierarchies. if(!rh->MagnifyTypeApplies(type)) ret = rh->getChildren(true); else{ CallGraph* cg = CallGraph::FindCallGraph(); assert(cg); ret = cg->getChildren(rh); } } return ret; }
// Rebuild CGN after we extracted parts of the code from ParentFunc into // NewFuncs. Builds CGNs for the NewFuncs and adds them to the current SCC. void coro::updateCallGraph(Function &ParentFunc, ArrayRef<Function *> NewFuncs, CallGraph &CG, CallGraphSCC &SCC) { // Rebuild CGN from scratch for the ParentFunc auto *ParentNode = CG[&ParentFunc]; ParentNode->removeAllCalledFunctions(); buildCGN(CG, ParentNode); SmallVector<CallGraphNode *, 8> Nodes(SCC.begin(), SCC.end()); for (Function *F : NewFuncs) { CallGraphNode *Callee = CG.getOrInsertFunction(F); Nodes.push_back(Callee); buildCGN(CG, Callee); } SCC.initialize(Nodes); }
// doInitialization - Initializes the vector of functions that have been // annotated with the noinline attribute. bool SimpleInliner::doInitialization(CallGraph &CG) { CA.setTargetData(getAnalysisIfAvailable<TargetData>()); Module &M = CG.getModule(); for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) if (!I->isDeclaration() && I->hasFnAttr(Attribute::NoInline)) NeverInline.insert(I); // Get llvm.noinline GlobalVariable *GV = M.getNamedGlobal("llvm.noinline"); if (GV == 0) return false; // Don't crash on invalid code if (!GV->hasDefinitiveInitializer()) return false; const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer()); if (InitList == 0) return false; // Iterate over each element and add to the NeverInline set for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { // Get Source const Constant *Elt = InitList->getOperand(i); if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(Elt)) if (CE->getOpcode() == Instruction::BitCast) Elt = CE->getOperand(0); // Insert into set of functions to never inline if (const Function *F = dyn_cast<Function>(Elt)) NeverInline.insert(F); } return false; }
// InlineCallIfPossible - If it is possible to inline the specified call site, // do so and update the CallGraph for this operation. static bool InlineCallIfPossible(CallSite CS, CallGraph &CG, const std::set<Function*> &SCCFunctions, const TargetData &TD) { Function *Callee = CS.getCalledFunction(); if (!InlineFunction(CS, &CG, &TD)) return false; // If we inlined the last possible call site to the function, delete the // function body now. if (Callee->use_empty() && Callee->hasInternalLinkage() && !SCCFunctions.count(Callee)) { DOUT << " -> Deleting dead function: " << Callee->getName() << "\n"; // Remove any call graph edges from the callee to its callees. CallGraphNode *CalleeNode = CG[Callee]; while (!CalleeNode->empty()) CalleeNode->removeCallEdgeTo((CalleeNode->end()-1)->second); // Removing the node for callee from the call graph and delete it. delete CG.removeFunctionFromModule(CalleeNode); ++NumDeleted; } return true; }
// When we see the coroutine the first time, we insert an indirect call to a // devirt trigger function and mark the coroutine that it is now ready for // split. static void prepareForSplit(Function &F, CallGraph &CG) { Module &M = *F.getParent(); #ifndef NDEBUG Function *DevirtFn = M.getFunction(CORO_DEVIRT_TRIGGER_FN); assert(DevirtFn && "coro.devirt.trigger function not found"); #endif F.addFnAttr(CORO_PRESPLIT_ATTR, PREPARED_FOR_SPLIT); // Insert an indirect call sequence that will be devirtualized by CoroElide // pass: // %0 = call i8* @llvm.coro.subfn.addr(i8* null, i8 -1) // %1 = bitcast i8* %0 to void(i8*)* // call void %1(i8* null) coro::LowererBase Lowerer(M); Instruction *InsertPt = F.getEntryBlock().getTerminator(); auto *Null = ConstantPointerNull::get(Type::getInt8PtrTy(F.getContext())); auto *DevirtFnAddr = Lowerer.makeSubFnCall(Null, CoroSubFnInst::RestartTrigger, InsertPt); auto *IndirectCall = CallInst::Create(DevirtFnAddr, Null, "", InsertPt); // Update CG graph with an indirect call we just added. CG[&F]->addCalledFunction(IndirectCall, CG.getCallsExternalNode()); }
bool InternalizePass::runOnModule(Module &M) { CallGraph *CG = getAnalysisIfAvailable<CallGraph>(); CallGraphNode *ExternalNode = CG ? CG->getExternalCallingNode() : 0; if (ExternalNames.empty()) { // Return if we're not in 'all but main' mode and have no external api if (!AllButMain) return false; // If no list or file of symbols was specified, check to see if there is a // "main" symbol defined in the module. If so, use it, otherwise do not // internalize the module, it must be a library or something. // Function *MainFunc = M.getFunction("main"); if (MainFunc == 0 || MainFunc->isDeclaration()) return false; // No main found, must be a library... // Preserve main, internalize all else. ExternalNames.insert(MainFunc->getName()); } bool Changed = false; // Never internalize functions which code-gen might insert. ExternalNames.insert("__stack_chk_fail"); // Mark all functions not in the api as internal. // FIXME: maybe use private linkage? for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) if (!I->isDeclaration() && // Function must be defined here // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !I->hasLocalLinkage() && // Can't already have internal linkage !ExternalNames.count(I->getName())) {// Not marked to keep external? I->setLinkage(GlobalValue::InternalLinkage); // Remove a callgraph edge from the external node to this function. if (ExternalNode) ExternalNode->removeOneAbstractEdgeTo((*CG)[I]); Changed = true; ++NumFunctions; DEBUG(dbgs() << "Internalizing func " << I->getName() << "\n"); } // Never internalize the llvm.used symbol. It is used to implement // attribute((used)). // FIXME: Shouldn't this just filter on llvm.metadata section?? ExternalNames.insert("llvm.used"); ExternalNames.insert("llvm.compiler.used"); // Never internalize anchors used by the machine module info, else the info // won't find them. (see MachineModuleInfo.) ExternalNames.insert("llvm.global_ctors"); ExternalNames.insert("llvm.global_dtors"); ExternalNames.insert("llvm.global.annotations"); // Never internalize symbols code-gen inserts. ExternalNames.insert("__stack_chk_guard"); // Mark all global variables with initializers that are not in the api as // internal as well. // FIXME: maybe use private linkage? for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) if (!I->isDeclaration() && !I->hasLocalLinkage() && // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !ExternalNames.count(I->getName())) { I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumGlobals; DEBUG(dbgs() << "Internalized gvar " << I->getName() << "\n"); } // Mark all aliases that are not in the api as internal as well. for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end(); I != E; ++I) if (!I->isDeclaration() && !I->hasInternalLinkage() && // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !ExternalNames.count(I->getName())) { I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumAliases; DEBUG(dbgs() << "Internalized alias " << I->getName() << "\n"); } return Changed; }
/// Remove dead functions that are not included in DNR (Do Not Remove) list. bool Inliner::removeDeadFunctions(CallGraph &CG, bool AlwaysInlineOnly) { SmallVector<CallGraphNode*, 16> FunctionsToRemove; SmallVector<CallGraphNode *, 16> DeadFunctionsInComdats; SmallDenseMap<const Comdat *, int, 16> ComdatEntriesAlive; auto RemoveCGN = [&](CallGraphNode *CGN) { // Remove any call graph edges from the function to its callees. CGN->removeAllCalledFunctions(); // Remove any edges from the external node to the function's call graph // node. These edges might have been made irrelegant due to // optimization of the program. CG.getExternalCallingNode()->removeAnyCallEdgeTo(CGN); // Removing the node for callee from the call graph and delete it. FunctionsToRemove.push_back(CGN); }; // Scan for all of the functions, looking for ones that should now be removed // from the program. Insert the dead ones in the FunctionsToRemove set. for (CallGraph::iterator I = CG.begin(), E = CG.end(); I != E; ++I) { CallGraphNode *CGN = I->second; Function *F = CGN->getFunction(); if (!F || F->isDeclaration()) continue; // Handle the case when this function is called and we only want to care // about always-inline functions. This is a bit of a hack to share code // between here and the InlineAlways pass. if (AlwaysInlineOnly && !F->hasFnAttribute(Attribute::AlwaysInline)) continue; // If the only remaining users of the function are dead constants, remove // them. F->removeDeadConstantUsers(); if (!F->isDefTriviallyDead()) continue; // It is unsafe to drop a function with discardable linkage from a COMDAT // without also dropping the other members of the COMDAT. // The inliner doesn't visit non-function entities which are in COMDAT // groups so it is unsafe to do so *unless* the linkage is local. if (!F->hasLocalLinkage()) { if (const Comdat *C = F->getComdat()) { --ComdatEntriesAlive[C]; DeadFunctionsInComdats.push_back(CGN); continue; } } RemoveCGN(CGN); } if (!DeadFunctionsInComdats.empty()) { // Count up all the entities in COMDAT groups auto ComdatGroupReferenced = [&](const Comdat *C) { auto I = ComdatEntriesAlive.find(C); if (I != ComdatEntriesAlive.end()) ++(I->getSecond()); }; for (const Function &F : CG.getModule()) if (const Comdat *C = F.getComdat()) ComdatGroupReferenced(C); for (const GlobalVariable &GV : CG.getModule().globals()) if (const Comdat *C = GV.getComdat()) ComdatGroupReferenced(C); for (const GlobalAlias &GA : CG.getModule().aliases()) if (const Comdat *C = GA.getComdat()) ComdatGroupReferenced(C); for (CallGraphNode *CGN : DeadFunctionsInComdats) { Function *F = CGN->getFunction(); const Comdat *C = F->getComdat(); int NumAlive = ComdatEntriesAlive[C]; // We can remove functions in a COMDAT group if the entire group is dead. assert(NumAlive >= 0); if (NumAlive > 0) continue; RemoveCGN(CGN); } } if (FunctionsToRemove.empty()) return false; // Now that we know which functions to delete, do so. We didn't want to do // this inline, because that would invalidate our CallGraph::iterator // objects. :( // // Note that it doesn't matter that we are iterating over a non-stable order // here to do this, it doesn't matter which order the functions are deleted // in. array_pod_sort(FunctionsToRemove.begin(), FunctionsToRemove.end()); FunctionsToRemove.erase(std::unique(FunctionsToRemove.begin(), FunctionsToRemove.end()), FunctionsToRemove.end()); for (SmallVectorImpl<CallGraphNode *>::iterator I = FunctionsToRemove.begin(), E = FunctionsToRemove.end(); I != E; ++I) { delete CG.removeFunctionFromModule(*I); ++NumDeleted; } return true; }
bool LegacyInlinerBase::doInitialization(CallGraph &CG) { if (InlinerFunctionImportStats != InlinerFunctionImportStatsOpts::No) ImportedFunctionsStats.setModuleInfo(CG.getModule()); return false; // No changes to CallGraph. }
static bool inlineCallsImpl(CallGraphSCC &SCC, CallGraph &CG, std::function<AssumptionCache &(Function &)> GetAssumptionCache, ProfileSummaryInfo *PSI, TargetLibraryInfo &TLI, bool InsertLifetime, function_ref<InlineCost(CallSite CS)> GetInlineCost, function_ref<AAResults &(Function &)> AARGetter, ImportedFunctionsInliningStatistics &ImportedFunctionsStats) { SmallPtrSet<Function *, 8> SCCFunctions; LLVM_DEBUG(dbgs() << "Inliner visiting SCC:"); for (CallGraphNode *Node : SCC) { Function *F = Node->getFunction(); if (F) SCCFunctions.insert(F); LLVM_DEBUG(dbgs() << " " << (F ? F->getName() : "INDIRECTNODE")); } // Scan through and identify all call sites ahead of time so that we only // inline call sites in the original functions, not call sites that result // from inlining other functions. SmallVector<std::pair<CallSite, int>, 16> CallSites; // When inlining a callee produces new call sites, we want to keep track of // the fact that they were inlined from the callee. This allows us to avoid // infinite inlining in some obscure cases. To represent this, we use an // index into the InlineHistory vector. SmallVector<std::pair<Function *, int>, 8> InlineHistory; for (CallGraphNode *Node : SCC) { Function *F = Node->getFunction(); if (!F || F->isDeclaration()) continue; OptimizationRemarkEmitter ORE(F); for (BasicBlock &BB : *F) for (Instruction &I : BB) { CallSite CS(cast<Value>(&I)); // If this isn't a call, or it is a call to an intrinsic, it can // never be inlined. if (!CS || isa<IntrinsicInst>(I)) continue; // If this is a direct call to an external function, we can never inline // it. If it is an indirect call, inlining may resolve it to be a // direct call, so we keep it. if (Function *Callee = CS.getCalledFunction()) if (Callee->isDeclaration()) { using namespace ore; ORE.emit([&]() { return OptimizationRemarkMissed(DEBUG_TYPE, "NoDefinition", &I) << NV("Callee", Callee) << " will not be inlined into " << NV("Caller", CS.getCaller()) << " because its definition is unavailable" << setIsVerbose(); }); continue; } CallSites.push_back(std::make_pair(CS, -1)); } } LLVM_DEBUG(dbgs() << ": " << CallSites.size() << " call sites.\n"); // If there are no calls in this function, exit early. if (CallSites.empty()) return false; // Now that we have all of the call sites, move the ones to functions in the // current SCC to the end of the list. unsigned FirstCallInSCC = CallSites.size(); for (unsigned i = 0; i < FirstCallInSCC; ++i) if (Function *F = CallSites[i].first.getCalledFunction()) if (SCCFunctions.count(F)) std::swap(CallSites[i--], CallSites[--FirstCallInSCC]); InlinedArrayAllocasTy InlinedArrayAllocas; InlineFunctionInfo InlineInfo(&CG, &GetAssumptionCache, PSI); // Now that we have all of the call sites, loop over them and inline them if // it looks profitable to do so. bool Changed = false; bool LocalChange; do { LocalChange = false; // Iterate over the outer loop because inlining functions can cause indirect // calls to become direct calls. // CallSites may be modified inside so ranged for loop can not be used. for (unsigned CSi = 0; CSi != CallSites.size(); ++CSi) { CallSite CS = CallSites[CSi].first; Function *Caller = CS.getCaller(); Function *Callee = CS.getCalledFunction(); // We can only inline direct calls to non-declarations. if (!Callee || Callee->isDeclaration()) continue; Instruction *Instr = CS.getInstruction(); bool IsTriviallyDead = isInstructionTriviallyDead(Instr, &TLI); int InlineHistoryID; if (!IsTriviallyDead) { // If this call site was obtained by inlining another function, verify // that the include path for the function did not include the callee // itself. If so, we'd be recursively inlining the same function, // which would provide the same callsites, which would cause us to // infinitely inline. InlineHistoryID = CallSites[CSi].second; if (InlineHistoryID != -1 && InlineHistoryIncludes(Callee, InlineHistoryID, InlineHistory)) continue; } // FIXME for new PM: because of the old PM we currently generate ORE and // in turn BFI on demand. With the new PM, the ORE dependency should // just become a regular analysis dependency. OptimizationRemarkEmitter ORE(Caller); Optional<InlineCost> OIC = shouldInline(CS, GetInlineCost, ORE); // If the policy determines that we should inline this function, // delete the call instead. if (!OIC) continue; // If this call site is dead and it is to a readonly function, we should // just delete the call instead of trying to inline it, regardless of // size. This happens because IPSCCP propagates the result out of the // call and then we're left with the dead call. if (IsTriviallyDead) { LLVM_DEBUG(dbgs() << " -> Deleting dead call: " << *Instr << "\n"); // Update the call graph by deleting the edge from Callee to Caller. CG[Caller]->removeCallEdgeFor(CS); Instr->eraseFromParent(); ++NumCallsDeleted; } else { // Get DebugLoc to report. CS will be invalid after Inliner. DebugLoc DLoc = CS->getDebugLoc(); BasicBlock *Block = CS.getParent(); // Attempt to inline the function. using namespace ore; if (!InlineCallIfPossible(CS, InlineInfo, InlinedArrayAllocas, InlineHistoryID, InsertLifetime, AARGetter, ImportedFunctionsStats)) { ORE.emit([&]() { return OptimizationRemarkMissed(DEBUG_TYPE, "NotInlined", DLoc, Block) << NV("Callee", Callee) << " will not be inlined into " << NV("Caller", Caller); }); continue; } ++NumInlined; ORE.emit([&]() { bool AlwaysInline = OIC->isAlways(); StringRef RemarkName = AlwaysInline ? "AlwaysInline" : "Inlined"; OptimizationRemark R(DEBUG_TYPE, RemarkName, DLoc, Block); R << NV("Callee", Callee) << " inlined into "; R << NV("Caller", Caller); if (AlwaysInline) R << " with cost=always"; else { R << " with cost=" << NV("Cost", OIC->getCost()); R << " (threshold=" << NV("Threshold", OIC->getThreshold()); R << ")"; } return R; }); // If inlining this function gave us any new call sites, throw them // onto our worklist to process. They are useful inline candidates. if (!InlineInfo.InlinedCalls.empty()) { // Create a new inline history entry for this, so that we remember // that these new callsites came about due to inlining Callee. int NewHistoryID = InlineHistory.size(); InlineHistory.push_back(std::make_pair(Callee, InlineHistoryID)); for (Value *Ptr : InlineInfo.InlinedCalls) CallSites.push_back(std::make_pair(CallSite(Ptr), NewHistoryID)); } } // If we inlined or deleted the last possible call site to the function, // delete the function body now. if (Callee && Callee->use_empty() && Callee->hasLocalLinkage() && // TODO: Can remove if in SCC now. !SCCFunctions.count(Callee) && // The function may be apparently dead, but if there are indirect // callgraph references to the node, we cannot delete it yet, this // could invalidate the CGSCC iterator. CG[Callee]->getNumReferences() == 0) { LLVM_DEBUG(dbgs() << " -> Deleting dead function: " << Callee->getName() << "\n"); CallGraphNode *CalleeNode = CG[Callee]; // Remove any call graph edges from the callee to its callees. CalleeNode->removeAllCalledFunctions(); // Removing the node for callee from the call graph and delete it. delete CG.removeFunctionFromModule(CalleeNode); ++NumDeleted; } // Remove this call site from the list. If possible, use // swap/pop_back for efficiency, but do not use it if doing so would // move a call site to a function in this SCC before the // 'FirstCallInSCC' barrier. if (SCC.isSingular()) { CallSites[CSi] = CallSites.back(); CallSites.pop_back(); } else { CallSites.erase(CallSites.begin() + CSi); } --CSi; Changed = true; LocalChange = true; } } while (LocalChange); return Changed; }
bool ArgPromotion::doInitialization(CallGraph &CG) { FunctionDIs = makeSubprogramMap(CG.getModule()); return CallGraphSCCPass::doInitialization(CG); }
/// Remove dead functions that are not included in DNR (Do Not Remove) list. bool LegacyInlinerBase::removeDeadFunctions(CallGraph &CG, bool AlwaysInlineOnly) { SmallVector<CallGraphNode *, 16> FunctionsToRemove; SmallVector<Function *, 16> DeadFunctionsInComdats; auto RemoveCGN = [&](CallGraphNode *CGN) { // Remove any call graph edges from the function to its callees. CGN->removeAllCalledFunctions(); // Remove any edges from the external node to the function's call graph // node. These edges might have been made irrelegant due to // optimization of the program. CG.getExternalCallingNode()->removeAnyCallEdgeTo(CGN); // Removing the node for callee from the call graph and delete it. FunctionsToRemove.push_back(CGN); }; // Scan for all of the functions, looking for ones that should now be removed // from the program. Insert the dead ones in the FunctionsToRemove set. for (const auto &I : CG) { CallGraphNode *CGN = I.second.get(); Function *F = CGN->getFunction(); if (!F || F->isDeclaration()) continue; // Handle the case when this function is called and we only want to care // about always-inline functions. This is a bit of a hack to share code // between here and the InlineAlways pass. if (AlwaysInlineOnly && !F->hasFnAttribute(Attribute::AlwaysInline)) continue; // If the only remaining users of the function are dead constants, remove // them. F->removeDeadConstantUsers(); if (!F->isDefTriviallyDead()) continue; // It is unsafe to drop a function with discardable linkage from a COMDAT // without also dropping the other members of the COMDAT. // The inliner doesn't visit non-function entities which are in COMDAT // groups so it is unsafe to do so *unless* the linkage is local. if (!F->hasLocalLinkage()) { if (F->hasComdat()) { DeadFunctionsInComdats.push_back(F); continue; } } RemoveCGN(CGN); } if (!DeadFunctionsInComdats.empty()) { // Filter out the functions whose comdats remain alive. filterDeadComdatFunctions(CG.getModule(), DeadFunctionsInComdats); // Remove the rest. for (Function *F : DeadFunctionsInComdats) RemoveCGN(CG[F]); } if (FunctionsToRemove.empty()) return false; // Now that we know which functions to delete, do so. We didn't want to do // this inline, because that would invalidate our CallGraph::iterator // objects. :( // // Note that it doesn't matter that we are iterating over a non-stable order // here to do this, it doesn't matter which order the functions are deleted // in. array_pod_sort(FunctionsToRemove.begin(), FunctionsToRemove.end()); FunctionsToRemove.erase( std::unique(FunctionsToRemove.begin(), FunctionsToRemove.end()), FunctionsToRemove.end()); for (CallGraphNode *CGN : FunctionsToRemove) { delete CG.removeFunctionFromModule(CGN); ++NumDeleted; } return true; }
bool CGPassManager::RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC, CallGraph &CG, bool &CallGraphUpToDate, bool &DevirtualizedCall) { bool Changed = false; PMDataManager *PM = P->getAsPMDataManager(); Module &M = CG.getModule(); if (!PM) { CallGraphSCCPass *CGSP = (CallGraphSCCPass *)P; if (!CallGraphUpToDate) { DevirtualizedCall |= RefreshCallGraph(CurSCC, CG, false); CallGraphUpToDate = true; } { unsigned InstrCount, SCCCount = 0; bool EmitICRemark = M.shouldEmitInstrCountChangedRemark(); TimeRegion PassTimer(getPassTimer(CGSP)); if (EmitICRemark) InstrCount = initSizeRemarkInfo(M); Changed = CGSP->runOnSCC(CurSCC); if (EmitICRemark) { // FIXME: Add getInstructionCount to CallGraphSCC. SCCCount = M.getInstructionCount(); // Is there a difference in the number of instructions in the module? if (SCCCount != InstrCount) { // Yep. Emit a remark and update InstrCount. int64_t Delta = static_cast<int64_t>(SCCCount) - static_cast<int64_t>(InstrCount); emitInstrCountChangedRemark(P, M, Delta, InstrCount); InstrCount = SCCCount; } } } // After the CGSCCPass is done, when assertions are enabled, use // RefreshCallGraph to verify that the callgraph was correctly updated. #ifndef NDEBUG if (Changed) RefreshCallGraph(CurSCC, CG, true); #endif return Changed; } assert(PM->getPassManagerType() == PMT_FunctionPassManager && "Invalid CGPassManager member"); FPPassManager *FPP = (FPPassManager*)P; // Run pass P on all functions in the current SCC. for (CallGraphNode *CGN : CurSCC) { if (Function *F = CGN->getFunction()) { dumpPassInfo(P, EXECUTION_MSG, ON_FUNCTION_MSG, F->getName()); { TimeRegion PassTimer(getPassTimer(FPP)); Changed |= FPP->runOnFunction(*F); } F->getContext().yield(); } } // The function pass(es) modified the IR, they may have clobbered the // callgraph. if (Changed && CallGraphUpToDate) { LLVM_DEBUG(dbgs() << "CGSCCPASSMGR: Pass Dirtied SCC: " << P->getPassName() << '\n'); CallGraphUpToDate = false; } return Changed; }
bool InternalizePass::runOnModule(Module &M) { CallGraph *CG = getAnalysisIfAvailable<CallGraph>(); CallGraphNode *ExternalNode = CG ? CG->getExternalCallingNode() : 0; bool Changed = false; // Never internalize functions which code-gen might insert. // FIXME: We should probably add this (and the __stack_chk_guard) via some // type of call-back in CodeGen. ExternalNames.insert("__stack_chk_fail"); // Mark all functions not in the api as internal. // FIXME: maybe use private linkage? for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) if (!I->isDeclaration() && // Function must be defined here // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !I->hasLocalLinkage() && // Can't already have internal linkage !ExternalNames.count(I->getName())) {// Not marked to keep external? I->setLinkage(GlobalValue::InternalLinkage); // Remove a callgraph edge from the external node to this function. if (ExternalNode) ExternalNode->removeOneAbstractEdgeTo((*CG)[I]); Changed = true; ++NumFunctions; DEBUG(dbgs() << "Internalizing func " << I->getName() << "\n"); } // Never internalize the llvm.used symbol. It is used to implement // attribute((used)). // FIXME: Shouldn't this just filter on llvm.metadata section?? ExternalNames.insert("llvm.used"); ExternalNames.insert("llvm.compiler.used"); // Never internalize anchors used by the machine module info, else the info // won't find them. (see MachineModuleInfo.) ExternalNames.insert("llvm.global_ctors"); ExternalNames.insert("llvm.global_dtors"); ExternalNames.insert("llvm.global.annotations"); // Never internalize symbols code-gen inserts. ExternalNames.insert("__stack_chk_guard"); // Mark all global variables with initializers that are not in the api as // internal as well. // FIXME: maybe use private linkage? for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) if (!I->isDeclaration() && !I->hasLocalLinkage() && // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !ExternalNames.count(I->getName())) { I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumGlobals; DEBUG(dbgs() << "Internalized gvar " << I->getName() << "\n"); } // Mark all aliases that are not in the api as internal as well. for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end(); I != E; ++I) if (!I->isDeclaration() && !I->hasInternalLinkage() && // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !ExternalNames.count(I->getName())) { I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumAliases; DEBUG(dbgs() << "Internalized alias " << I->getName() << "\n"); } return Changed; }
bool InternalizePass::runOnModule(Module &M) { CallGraphWrapperPass *CGPass = getAnalysisIfAvailable<CallGraphWrapperPass>(); CallGraph *CG = CGPass ? &CGPass->getCallGraph() : 0; CallGraphNode *ExternalNode = CG ? CG->getExternalCallingNode() : 0; bool Changed = false; SmallPtrSet<GlobalValue *, 8> Used; collectUsedGlobalVariables(M, Used, false); // We must assume that globals in llvm.used have a reference that not even // the linker can see, so we don't internalize them. // For llvm.compiler.used the situation is a bit fuzzy. The assembler and // linker can drop those symbols. If this pass is running as part of LTO, // one might think that it could just drop llvm.compiler.used. The problem // is that even in LTO llvm doesn't see every reference. For example, // we don't see references from function local inline assembly. To be // conservative, we internalize symbols in llvm.compiler.used, but we // keep llvm.compiler.used so that the symbol is not deleted by llvm. for (SmallPtrSet<GlobalValue *, 8>::iterator I = Used.begin(), E = Used.end(); I != E; ++I) { GlobalValue *V = *I; ExternalNames.insert(V->getName()); } // Mark all functions not in the api as internal. for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) { if (!shouldInternalize(*I, ExternalNames, OnlyHidden)) continue; I->setLinkage(GlobalValue::InternalLinkage); if (ExternalNode) // Remove a callgraph edge from the external node to this function. ExternalNode->removeOneAbstractEdgeTo((*CG)[I]); Changed = true; ++NumFunctions; DEBUG(dbgs() << "Internalizing func " << I->getName() << "\n"); } // Never internalize the llvm.used symbol. It is used to implement // attribute((used)). // FIXME: Shouldn't this just filter on llvm.metadata section?? ExternalNames.insert("llvm.used"); ExternalNames.insert("llvm.compiler.used"); // Never internalize anchors used by the machine module info, else the info // won't find them. (see MachineModuleInfo.) ExternalNames.insert("llvm.global_ctors"); ExternalNames.insert("llvm.global_dtors"); ExternalNames.insert("llvm.global.annotations"); // Never internalize symbols code-gen inserts. // FIXME: We should probably add this (and the __stack_chk_guard) via some // type of call-back in CodeGen. ExternalNames.insert("__stack_chk_fail"); ExternalNames.insert("__stack_chk_guard"); // Mark all global variables with initializers that are not in the api as // internal as well. for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) { if (!shouldInternalize(*I, ExternalNames, OnlyHidden)) continue; I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumGlobals; DEBUG(dbgs() << "Internalized gvar " << I->getName() << "\n"); } // Mark all aliases that are not in the api as internal as well. for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end(); I != E; ++I) { if (!shouldInternalize(*I, ExternalNames, OnlyHidden)) continue; I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumAliases; DEBUG(dbgs() << "Internalized alias " << I->getName() << "\n"); } return Changed; }
int main(int argc, const char* argv[]) { if (argc < 2) { cout << "Not enough arguments. Provide at least the dot file to read" << endl; return 1; } Parameters::init(); Infos infos; GraphReader reader(infos); CallGraph* graph = reader.read(argv[1]); ofstream stream; stream.open("main.cpp"); stream << "//Auto generated by inlining analyzer" << endl; stream << "#include <iostream>" << endl << endl; stream << "using std::cout;" << endl; stream << "using std::endl;" << endl << endl; string mainFunction = ""; //Print the declarations FunctionIterator first, last; for (boost::tie(first, last) = graph->functions(); first != last; ++first) { string name = (*graph)[*first].name; transform(name); if (filter(name)) { continue; } if ((*graph)[*first].calls == 0) { mainFunction = name; } //Declaration stream << "void FFF" << name << "() __attribute__ ((noinline));" << endl; } //Print the definitions for (boost::tie(first, last) = graph->functions(); first != last; ++first) { string name = (*graph)[*first].name; transform(name); if (filter(name)) { continue; } //Definition stream << "void FFF" << name << "() {" << endl; stream << "\tcout << \"I'm in " << name << "\" << endl;" << endl; OutCallSiteIterator it, end; for (boost::tie(it, end) = boost::out_edges(*first, *graph->getGraph()); it != end; ++it) { string called = (*graph)[boost::target(*it, *graph->getGraph())].name; transform(called); if (filter(called)) { continue; } stream << "\tFFF" << called << "();" << endl; } stream << "}" << endl << endl; } //Write main function stream << "int main(){" << endl; stream << "\tcout << \"I'm in main()\" << endl;" << endl; stream << "\tFFF" << mainFunction << "();" << endl; stream << "\treturn 0;" << endl; stream << "}" << endl; stream.close(); delete graph; return 0; }