| //===- CallGraphSCCPass.cpp - Pass that operates BU on call graph ---------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the CallGraphSCCPass class, which is used for passes |
| // which are implemented as bottom-up traversals on the call graph. Because |
| // there may be cycles in the call graph, passes of this type operate on the |
| // call-graph in SCC order: that is, they process function bottom-up, except for |
| // recursive functions, which they process all at once. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Analysis/CallGraphSCCPass.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/SCCIterator.h" |
| #include "llvm/ADT/Statistic.h" |
| #include "llvm/Analysis/CallGraph.h" |
| #include "llvm/IR/Function.h" |
| #include "llvm/IR/IRPrintingPasses.h" |
| #include "llvm/IR/Intrinsics.h" |
| #include "llvm/IR/LLVMContext.h" |
| #include "llvm/IR/LegacyPassManagers.h" |
| #include "llvm/IR/Module.h" |
| #include "llvm/IR/OptBisect.h" |
| #include "llvm/IR/PassTimingInfo.h" |
| #include "llvm/Pass.h" |
| #include "llvm/Support/CommandLine.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/Timer.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include <cassert> |
| #include <string> |
| #include <utility> |
| #include <vector> |
| |
| using namespace llvm; |
| |
| #define DEBUG_TYPE "cgscc-passmgr" |
| |
| static cl::opt<unsigned> |
| MaxIterations("max-cg-scc-iterations", cl::ReallyHidden, cl::init(4)); |
| |
| STATISTIC(MaxSCCIterations, "Maximum CGSCCPassMgr iterations on one SCC"); |
| |
| //===----------------------------------------------------------------------===// |
| // CGPassManager |
| // |
| /// CGPassManager manages FPPassManagers and CallGraphSCCPasses. |
| |
| namespace { |
| |
| class CGPassManager : public ModulePass, public PMDataManager { |
| public: |
| static char ID; |
| |
| explicit CGPassManager() : ModulePass(ID), PMDataManager() {} |
| |
| /// Execute all of the passes scheduled for execution. Keep track of |
| /// whether any of the passes modifies the module, and if so, return true. |
| bool runOnModule(Module &M) override; |
| |
| using ModulePass::doInitialization; |
| using ModulePass::doFinalization; |
| |
| bool doInitialization(CallGraph &CG); |
| bool doFinalization(CallGraph &CG); |
| |
| /// Pass Manager itself does not invalidate any analysis info. |
| void getAnalysisUsage(AnalysisUsage &Info) const override { |
| // CGPassManager walks SCC and it needs CallGraph. |
| Info.addRequired<CallGraphWrapperPass>(); |
| Info.setPreservesAll(); |
| } |
| |
| StringRef getPassName() const override { return "CallGraph Pass Manager"; } |
| |
| PMDataManager *getAsPMDataManager() override { return this; } |
| Pass *getAsPass() override { return this; } |
| |
| // Print passes managed by this manager |
| void dumpPassStructure(unsigned Offset) override { |
| errs().indent(Offset*2) << "Call Graph SCC Pass Manager\n"; |
| for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) { |
| Pass *P = getContainedPass(Index); |
| P->dumpPassStructure(Offset + 1); |
| dumpLastUses(P, Offset+1); |
| } |
| } |
| |
| Pass *getContainedPass(unsigned N) { |
| assert(N < PassVector.size() && "Pass number out of range!"); |
| return static_cast<Pass *>(PassVector[N]); |
| } |
| |
| PassManagerType getPassManagerType() const override { |
| return PMT_CallGraphPassManager; |
| } |
| |
| private: |
| bool RunAllPassesOnSCC(CallGraphSCC &CurSCC, CallGraph &CG, |
| bool &DevirtualizedCall); |
| |
| bool RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC, |
| CallGraph &CG, bool &CallGraphUpToDate, |
| bool &DevirtualizedCall); |
| bool RefreshCallGraph(const CallGraphSCC &CurSCC, CallGraph &CG, |
| bool IsCheckingMode); |
| }; |
| |
| } // end anonymous namespace. |
| |
| char CGPassManager::ID = 0; |
| |
| 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; |
| StringMap<std::pair<unsigned, unsigned>> FunctionToInstrCount; |
| bool EmitICRemark = M.shouldEmitInstrCountChangedRemark(); |
| TimeRegion PassTimer(getPassTimer(CGSP)); |
| if (EmitICRemark) |
| InstrCount = initSizeRemarkInfo(M, FunctionToInstrCount); |
| 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, |
| FunctionToInstrCount); |
| 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; |
| } |
| |
| /// Scan the functions in the specified CFG and resync the |
| /// callgraph with the call sites found in it. This is used after |
| /// FunctionPasses have potentially munged the callgraph, and can be used after |
| /// CallGraphSCC passes to verify that they correctly updated the callgraph. |
| /// |
| /// This function returns true if it devirtualized an existing function call, |
| /// meaning it turned an indirect call into a direct call. This happens when |
| /// a function pass like GVN optimizes away stuff feeding the indirect call. |
| /// This never happens in checking mode. |
| bool CGPassManager::RefreshCallGraph(const CallGraphSCC &CurSCC, CallGraph &CG, |
| bool CheckingMode) { |
| DenseMap<Value *, CallGraphNode *> Calls; |
| |
| LLVM_DEBUG(dbgs() << "CGSCCPASSMGR: Refreshing SCC with " << CurSCC.size() |
| << " nodes:\n"; |
| for (CallGraphNode *CGN |
| : CurSCC) CGN->dump();); |
| |
| bool MadeChange = false; |
| bool DevirtualizedCall = false; |
| |
| // Scan all functions in the SCC. |
| unsigned FunctionNo = 0; |
| for (CallGraphSCC::iterator SCCIdx = CurSCC.begin(), E = CurSCC.end(); |
| SCCIdx != E; ++SCCIdx, ++FunctionNo) { |
| CallGraphNode *CGN = *SCCIdx; |
| Function *F = CGN->getFunction(); |
| if (!F || F->isDeclaration()) continue; |
| |
| // Walk the function body looking for call sites. Sync up the call sites in |
| // CGN with those actually in the function. |
| |
| // Keep track of the number of direct and indirect calls that were |
| // invalidated and removed. |
| unsigned NumDirectRemoved = 0, NumIndirectRemoved = 0; |
| |
| // Get the set of call sites currently in the function. |
| for (CallGraphNode::iterator I = CGN->begin(), E = CGN->end(); I != E; ) { |
| // If this call site is null, then the function pass deleted the call |
| // entirely and the WeakTrackingVH nulled it out. |
| auto *Call = dyn_cast_or_null<CallBase>(I->first); |
| if (!I->first || |
| // If we've already seen this call site, then the FunctionPass RAUW'd |
| // one call with another, which resulted in two "uses" in the edge |
| // list of the same call. |
| Calls.count(I->first) || |
| |
| // If the call edge is not from a call or invoke, or it is a |
| // instrinsic call, then the function pass RAUW'd a call with |
| // another value. This can happen when constant folding happens |
| // of well known functions etc. |
| !Call || |
| (Call->getCalledFunction() && |
| Call->getCalledFunction()->isIntrinsic() && |
| Intrinsic::isLeaf(Call->getCalledFunction()->getIntrinsicID()))) { |
| assert(!CheckingMode && |
| "CallGraphSCCPass did not update the CallGraph correctly!"); |
| |
| // If this was an indirect call site, count it. |
| if (!I->second->getFunction()) |
| ++NumIndirectRemoved; |
| else |
| ++NumDirectRemoved; |
| |
| // Just remove the edge from the set of callees, keep track of whether |
| // I points to the last element of the vector. |
| bool WasLast = I + 1 == E; |
| CGN->removeCallEdge(I); |
| |
| // If I pointed to the last element of the vector, we have to bail out: |
| // iterator checking rejects comparisons of the resultant pointer with |
| // end. |
| if (WasLast) |
| break; |
| E = CGN->end(); |
| continue; |
| } |
| |
| assert(!Calls.count(I->first) && |
| "Call site occurs in node multiple times"); |
| |
| if (Call) { |
| Function *Callee = Call->getCalledFunction(); |
| // Ignore intrinsics because they're not really function calls. |
| if (!Callee || !(Callee->isIntrinsic())) |
| Calls.insert(std::make_pair(I->first, I->second)); |
| } |
| ++I; |
| } |
| |
| // Loop over all of the instructions in the function, getting the callsites. |
| // Keep track of the number of direct/indirect calls added. |
| unsigned NumDirectAdded = 0, NumIndirectAdded = 0; |
| |
| for (BasicBlock &BB : *F) |
| for (Instruction &I : BB) { |
| auto *Call = dyn_cast<CallBase>(&I); |
| if (!Call) |
| continue; |
| Function *Callee = Call->getCalledFunction(); |
| if (Callee && Callee->isIntrinsic()) |
| continue; |
| |
| // If this call site already existed in the callgraph, just verify it |
| // matches up to expectations and remove it from Calls. |
| DenseMap<Value *, CallGraphNode *>::iterator ExistingIt = |
| Calls.find(Call); |
| if (ExistingIt != Calls.end()) { |
| CallGraphNode *ExistingNode = ExistingIt->second; |
| |
| // Remove from Calls since we have now seen it. |
| Calls.erase(ExistingIt); |
| |
| // Verify that the callee is right. |
| if (ExistingNode->getFunction() == Call->getCalledFunction()) |
| continue; |
| |
| // If we are in checking mode, we are not allowed to actually mutate |
| // the callgraph. If this is a case where we can infer that the |
| // callgraph is less precise than it could be (e.g. an indirect call |
| // site could be turned direct), don't reject it in checking mode, and |
| // don't tweak it to be more precise. |
| if (CheckingMode && Call->getCalledFunction() && |
| ExistingNode->getFunction() == nullptr) |
| continue; |
| |
| assert(!CheckingMode && |
| "CallGraphSCCPass did not update the CallGraph correctly!"); |
| |
| // If not, we either went from a direct call to indirect, indirect to |
| // direct, or direct to different direct. |
| CallGraphNode *CalleeNode; |
| if (Function *Callee = Call->getCalledFunction()) { |
| CalleeNode = CG.getOrInsertFunction(Callee); |
| // Keep track of whether we turned an indirect call into a direct |
| // one. |
| if (!ExistingNode->getFunction()) { |
| DevirtualizedCall = true; |
| LLVM_DEBUG(dbgs() << " CGSCCPASSMGR: Devirtualized call to '" |
| << Callee->getName() << "'\n"); |
| } |
| } else { |
| CalleeNode = CG.getCallsExternalNode(); |
| } |
| |
| // Update the edge target in CGN. |
| CGN->replaceCallEdge(*Call, *Call, CalleeNode); |
| MadeChange = true; |
| continue; |
| } |
| |
| assert(!CheckingMode && |
| "CallGraphSCCPass did not update the CallGraph correctly!"); |
| |
| // If the call site didn't exist in the CGN yet, add it. |
| CallGraphNode *CalleeNode; |
| if (Function *Callee = Call->getCalledFunction()) { |
| CalleeNode = CG.getOrInsertFunction(Callee); |
| ++NumDirectAdded; |
| } else { |
| CalleeNode = CG.getCallsExternalNode(); |
| ++NumIndirectAdded; |
| } |
| |
| CGN->addCalledFunction(Call, CalleeNode); |
| MadeChange = true; |
| } |
| |
| // We scanned the old callgraph node, removing invalidated call sites and |
| // then added back newly found call sites. One thing that can happen is |
| // that an old indirect call site was deleted and replaced with a new direct |
| // call. In this case, we have devirtualized a call, and CGSCCPM would like |
| // to iteratively optimize the new code. Unfortunately, we don't really |
| // have a great way to detect when this happens. As an approximation, we |
| // just look at whether the number of indirect calls is reduced and the |
| // number of direct calls is increased. There are tons of ways to fool this |
| // (e.g. DCE'ing an indirect call and duplicating an unrelated block with a |
| // direct call) but this is close enough. |
| if (NumIndirectRemoved > NumIndirectAdded && |
| NumDirectRemoved < NumDirectAdded) |
| DevirtualizedCall = true; |
| |
| // After scanning this function, if we still have entries in callsites, then |
| // they are dangling pointers. WeakTrackingVH should save us for this, so |
| // abort if |
| // this happens. |
| assert(Calls.empty() && "Dangling pointers found in call sites map"); |
| |
| // Periodically do an explicit clear to remove tombstones when processing |
| // large scc's. |
| if ((FunctionNo & 15) == 15) |
| Calls.clear(); |
| } |
| |
| LLVM_DEBUG(if (MadeChange) { |
| dbgs() << "CGSCCPASSMGR: Refreshed SCC is now:\n"; |
| for (CallGraphNode *CGN : CurSCC) |
| CGN->dump(); |
| if (DevirtualizedCall) |
| dbgs() << "CGSCCPASSMGR: Refresh devirtualized a call!\n"; |
| } else { |
| dbgs() << "CGSCCPASSMGR: SCC Refresh didn't change call graph.\n"; |
| }); |
| (void)MadeChange; |
| |
| return DevirtualizedCall; |
| } |
| |
| /// Execute the body of the entire pass manager on the specified SCC. |
| /// This keeps track of whether a function pass devirtualizes |
| /// any calls and returns it in DevirtualizedCall. |
| bool CGPassManager::RunAllPassesOnSCC(CallGraphSCC &CurSCC, CallGraph &CG, |
| bool &DevirtualizedCall) { |
| bool Changed = false; |
| |
| // Keep track of whether the callgraph is known to be up-to-date or not. |
| // The CGSSC pass manager runs two types of passes: |
| // CallGraphSCC Passes and other random function passes. Because other |
| // random function passes are not CallGraph aware, they may clobber the |
| // call graph by introducing new calls or deleting other ones. This flag |
| // is set to false when we run a function pass so that we know to clean up |
| // the callgraph when we need to run a CGSCCPass again. |
| bool CallGraphUpToDate = true; |
| |
| // Run all passes on current SCC. |
| for (unsigned PassNo = 0, e = getNumContainedPasses(); |
| PassNo != e; ++PassNo) { |
| Pass *P = getContainedPass(PassNo); |
| |
| // If we're in -debug-pass=Executions mode, construct the SCC node list, |
| // otherwise avoid constructing this string as it is expensive. |
| if (isPassDebuggingExecutionsOrMore()) { |
| std::string Functions; |
| #ifndef NDEBUG |
| raw_string_ostream OS(Functions); |
| for (CallGraphSCC::iterator I = CurSCC.begin(), E = CurSCC.end(); |
| I != E; ++I) { |
| if (I != CurSCC.begin()) OS << ", "; |
| (*I)->print(OS); |
| } |
| OS.flush(); |
| #endif |
| dumpPassInfo(P, EXECUTION_MSG, ON_CG_MSG, Functions); |
| } |
| dumpRequiredSet(P); |
| |
| initializeAnalysisImpl(P); |
| |
| // Actually run this pass on the current SCC. |
| Changed |= RunPassOnSCC(P, CurSCC, CG, |
| CallGraphUpToDate, DevirtualizedCall); |
| |
| if (Changed) |
| dumpPassInfo(P, MODIFICATION_MSG, ON_CG_MSG, ""); |
| dumpPreservedSet(P); |
| |
| verifyPreservedAnalysis(P); |
| removeNotPreservedAnalysis(P); |
| recordAvailableAnalysis(P); |
| removeDeadPasses(P, "", ON_CG_MSG); |
| } |
| |
| // If the callgraph was left out of date (because the last pass run was a |
| // functionpass), refresh it before we move on to the next SCC. |
| if (!CallGraphUpToDate) |
| DevirtualizedCall |= RefreshCallGraph(CurSCC, CG, false); |
| return Changed; |
| } |
| |
| /// Execute all of the passes scheduled for execution. Keep track of |
| /// whether any of the passes modifies the module, and if so, return true. |
| bool CGPassManager::runOnModule(Module &M) { |
| CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph(); |
| bool Changed = doInitialization(CG); |
| |
| // Walk the callgraph in bottom-up SCC order. |
| scc_iterator<CallGraph*> CGI = scc_begin(&CG); |
| |
| CallGraphSCC CurSCC(CG, &CGI); |
| while (!CGI.isAtEnd()) { |
| // Copy the current SCC and increment past it so that the pass can hack |
| // on the SCC if it wants to without invalidating our iterator. |
| const std::vector<CallGraphNode *> &NodeVec = *CGI; |
| CurSCC.initialize(NodeVec); |
| ++CGI; |
| |
| // At the top level, we run all the passes in this pass manager on the |
| // functions in this SCC. However, we support iterative compilation in the |
| // case where a function pass devirtualizes a call to a function. For |
| // example, it is very common for a function pass (often GVN or instcombine) |
| // to eliminate the addressing that feeds into a call. With that improved |
| // information, we would like the call to be an inline candidate, infer |
| // mod-ref information etc. |
| // |
| // Because of this, we allow iteration up to a specified iteration count. |
| // This only happens in the case of a devirtualized call, so we only burn |
| // compile time in the case that we're making progress. We also have a hard |
| // iteration count limit in case there is crazy code. |
| unsigned Iteration = 0; |
| bool DevirtualizedCall = false; |
| do { |
| LLVM_DEBUG(if (Iteration) dbgs() |
| << " SCCPASSMGR: Re-visiting SCC, iteration #" << Iteration |
| << '\n'); |
| DevirtualizedCall = false; |
| Changed |= RunAllPassesOnSCC(CurSCC, CG, DevirtualizedCall); |
| } while (Iteration++ < MaxIterations && DevirtualizedCall); |
| |
| if (DevirtualizedCall) |
| LLVM_DEBUG(dbgs() << " CGSCCPASSMGR: Stopped iteration after " |
| << Iteration |
| << " times, due to -max-cg-scc-iterations\n"); |
| |
| MaxSCCIterations.updateMax(Iteration); |
| } |
| Changed |= doFinalization(CG); |
| return Changed; |
| } |
| |
| /// Initialize CG |
| bool CGPassManager::doInitialization(CallGraph &CG) { |
| bool Changed = false; |
| for (unsigned i = 0, e = getNumContainedPasses(); i != e; ++i) { |
| if (PMDataManager *PM = getContainedPass(i)->getAsPMDataManager()) { |
| assert(PM->getPassManagerType() == PMT_FunctionPassManager && |
| "Invalid CGPassManager member"); |
| Changed |= ((FPPassManager*)PM)->doInitialization(CG.getModule()); |
| } else { |
| Changed |= ((CallGraphSCCPass*)getContainedPass(i))->doInitialization(CG); |
| } |
| } |
| return Changed; |
| } |
| |
| /// Finalize CG |
| bool CGPassManager::doFinalization(CallGraph &CG) { |
| bool Changed = false; |
| for (unsigned i = 0, e = getNumContainedPasses(); i != e; ++i) { |
| if (PMDataManager *PM = getContainedPass(i)->getAsPMDataManager()) { |
| assert(PM->getPassManagerType() == PMT_FunctionPassManager && |
| "Invalid CGPassManager member"); |
| Changed |= ((FPPassManager*)PM)->doFinalization(CG.getModule()); |
| } else { |
| Changed |= ((CallGraphSCCPass*)getContainedPass(i))->doFinalization(CG); |
| } |
| } |
| return Changed; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // CallGraphSCC Implementation |
| //===----------------------------------------------------------------------===// |
| |
| /// This informs the SCC and the pass manager that the specified |
| /// Old node has been deleted, and New is to be used in its place. |
| void CallGraphSCC::ReplaceNode(CallGraphNode *Old, CallGraphNode *New) { |
| assert(Old != New && "Should not replace node with self"); |
| for (unsigned i = 0; ; ++i) { |
| assert(i != Nodes.size() && "Node not in SCC"); |
| if (Nodes[i] != Old) continue; |
| Nodes[i] = New; |
| break; |
| } |
| |
| // Update the active scc_iterator so that it doesn't contain dangling |
| // pointers to the old CallGraphNode. |
| scc_iterator<CallGraph*> *CGI = (scc_iterator<CallGraph*>*)Context; |
| CGI->ReplaceNode(Old, New); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // CallGraphSCCPass Implementation |
| //===----------------------------------------------------------------------===// |
| |
| /// Assign pass manager to manage this pass. |
| void CallGraphSCCPass::assignPassManager(PMStack &PMS, |
| PassManagerType PreferredType) { |
| // Find CGPassManager |
| while (!PMS.empty() && |
| PMS.top()->getPassManagerType() > PMT_CallGraphPassManager) |
| PMS.pop(); |
| |
| assert(!PMS.empty() && "Unable to handle Call Graph Pass"); |
| CGPassManager *CGP; |
| |
| if (PMS.top()->getPassManagerType() == PMT_CallGraphPassManager) |
| CGP = (CGPassManager*)PMS.top(); |
| else { |
| // Create new Call Graph SCC Pass Manager if it does not exist. |
| assert(!PMS.empty() && "Unable to create Call Graph Pass Manager"); |
| PMDataManager *PMD = PMS.top(); |
| |
| // [1] Create new Call Graph Pass Manager |
| CGP = new CGPassManager(); |
| |
| // [2] Set up new manager's top level manager |
| PMTopLevelManager *TPM = PMD->getTopLevelManager(); |
| TPM->addIndirectPassManager(CGP); |
| |
| // [3] Assign manager to manage this new manager. This may create |
| // and push new managers into PMS |
| Pass *P = CGP; |
| TPM->schedulePass(P); |
| |
| // [4] Push new manager into PMS |
| PMS.push(CGP); |
| } |
| |
| CGP->add(this); |
| } |
| |
| /// For this class, we declare that we require and preserve the call graph. |
| /// If the derived class implements this method, it should |
| /// always explicitly call the implementation here. |
| void CallGraphSCCPass::getAnalysisUsage(AnalysisUsage &AU) const { |
| AU.addRequired<CallGraphWrapperPass>(); |
| AU.addPreserved<CallGraphWrapperPass>(); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // PrintCallGraphPass Implementation |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| /// PrintCallGraphPass - Print a Module corresponding to a call graph. |
| /// |
| class PrintCallGraphPass : public CallGraphSCCPass { |
| std::string Banner; |
| raw_ostream &OS; // raw_ostream to print on. |
| |
| public: |
| static char ID; |
| |
| PrintCallGraphPass(const std::string &B, raw_ostream &OS) |
| : CallGraphSCCPass(ID), Banner(B), OS(OS) {} |
| |
| void getAnalysisUsage(AnalysisUsage &AU) const override { |
| AU.setPreservesAll(); |
| } |
| |
| bool runOnSCC(CallGraphSCC &SCC) override { |
| bool BannerPrinted = false; |
| auto PrintBannerOnce = [&]() { |
| if (BannerPrinted) |
| return; |
| OS << Banner; |
| BannerPrinted = true; |
| }; |
| |
| bool NeedModule = llvm::forcePrintModuleIR(); |
| if (isFunctionInPrintList("*") && NeedModule) { |
| PrintBannerOnce(); |
| OS << "\n"; |
| SCC.getCallGraph().getModule().print(OS, nullptr); |
| return false; |
| } |
| bool FoundFunction = false; |
| for (CallGraphNode *CGN : SCC) { |
| if (Function *F = CGN->getFunction()) { |
| if (!F->isDeclaration() && isFunctionInPrintList(F->getName())) { |
| FoundFunction = true; |
| if (!NeedModule) { |
| PrintBannerOnce(); |
| F->print(OS); |
| } |
| } |
| } else if (isFunctionInPrintList("*")) { |
| PrintBannerOnce(); |
| OS << "\nPrinting <null> Function\n"; |
| } |
| } |
| if (NeedModule && FoundFunction) { |
| PrintBannerOnce(); |
| OS << "\n"; |
| SCC.getCallGraph().getModule().print(OS, nullptr); |
| } |
| return false; |
| } |
| |
| StringRef getPassName() const override { return "Print CallGraph IR"; } |
| }; |
| |
| } // end anonymous namespace. |
| |
| char PrintCallGraphPass::ID = 0; |
| |
| Pass *CallGraphSCCPass::createPrinterPass(raw_ostream &OS, |
| const std::string &Banner) const { |
| return new PrintCallGraphPass(Banner, OS); |
| } |
| |
| static std::string getDescription(const CallGraphSCC &SCC) { |
| std::string Desc = "SCC ("; |
| bool First = true; |
| for (CallGraphNode *CGN : SCC) { |
| if (First) |
| First = false; |
| else |
| Desc += ", "; |
| Function *F = CGN->getFunction(); |
| if (F) |
| Desc += F->getName(); |
| else |
| Desc += "<<null function>>"; |
| } |
| Desc += ")"; |
| return Desc; |
| } |
| |
| bool CallGraphSCCPass::skipSCC(CallGraphSCC &SCC) const { |
| OptPassGate &Gate = |
| SCC.getCallGraph().getModule().getContext().getOptPassGate(); |
| return Gate.isEnabled() && !Gate.shouldRunPass(this, getDescription(SCC)); |
| } |
| |
| char DummyCGSCCPass::ID = 0; |
| |
| INITIALIZE_PASS(DummyCGSCCPass, "DummyCGSCCPass", "DummyCGSCCPass", false, |
| false) |
