761 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			761 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===- CallGraphSCCPass.cpp - Pass that operates BU on call graph ---------===//
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| //
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| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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| // See https://llvm.org/LICENSE.txt for license information.
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| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // This file implements the CallGraphSCCPass class, which is used for passes
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| // which are implemented as bottom-up traversals on the call graph.  Because
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| // there may be cycles in the call graph, passes of this type operate on the
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| // call-graph in SCC order: that is, they process function bottom-up, except for
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| // recursive functions, which they process all at once.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "llvm/Analysis/CallGraphSCCPass.h"
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| #include "llvm/ADT/DenseMap.h"
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| #include "llvm/ADT/SCCIterator.h"
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| #include "llvm/ADT/Statistic.h"
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| #include "llvm/Analysis/CallGraph.h"
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| #include "llvm/IR/AbstractCallSite.h"
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| #include "llvm/IR/Function.h"
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| #include "llvm/IR/Intrinsics.h"
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| #include "llvm/IR/LLVMContext.h"
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| #include "llvm/IR/LegacyPassManagers.h"
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| #include "llvm/IR/Module.h"
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| #include "llvm/IR/OptBisect.h"
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| #include "llvm/IR/PassTimingInfo.h"
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| #include "llvm/IR/PrintPasses.h"
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| #include "llvm/Pass.h"
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| #include "llvm/Support/CommandLine.h"
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| #include "llvm/Support/Debug.h"
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| #include "llvm/Support/Timer.h"
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| #include "llvm/Support/raw_ostream.h"
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| #include <cassert>
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| #include <string>
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| #include <utility>
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| #include <vector>
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| 
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| using namespace llvm;
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| 
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| #define DEBUG_TYPE "cgscc-passmgr"
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| 
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| namespace llvm {
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| cl::opt<unsigned> MaxDevirtIterations("max-devirt-iterations", cl::ReallyHidden,
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|                                       cl::init(4));
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| }
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| 
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| STATISTIC(MaxSCCIterations, "Maximum CGSCCPassMgr iterations on one SCC");
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| 
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| //===----------------------------------------------------------------------===//
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| // CGPassManager
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| //
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| /// CGPassManager manages FPPassManagers and CallGraphSCCPasses.
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| 
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| namespace {
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| 
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| class CGPassManager : public ModulePass, public PMDataManager {
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| public:
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|   static char ID;
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| 
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|   explicit CGPassManager() : ModulePass(ID) {}
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| 
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|   /// Execute all of the passes scheduled for execution.  Keep track of
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|   /// whether any of the passes modifies the module, and if so, return true.
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|   bool runOnModule(Module &M) override;
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| 
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|   using ModulePass::doInitialization;
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|   using ModulePass::doFinalization;
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| 
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|   bool doInitialization(CallGraph &CG);
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|   bool doFinalization(CallGraph &CG);
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| 
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|   /// Pass Manager itself does not invalidate any analysis info.
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|   void getAnalysisUsage(AnalysisUsage &Info) const override {
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|     // CGPassManager walks SCC and it needs CallGraph.
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|     Info.addRequired<CallGraphWrapperPass>();
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|     Info.setPreservesAll();
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|   }
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| 
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|   StringRef getPassName() const override { return "CallGraph Pass Manager"; }
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| 
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|   PMDataManager *getAsPMDataManager() override { return this; }
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|   Pass *getAsPass() override { return this; }
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| 
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|   // Print passes managed by this manager
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|   void dumpPassStructure(unsigned Offset) override {
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|     errs().indent(Offset*2) << "Call Graph SCC Pass Manager\n";
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|     for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
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|       Pass *P = getContainedPass(Index);
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|       P->dumpPassStructure(Offset + 1);
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|       dumpLastUses(P, Offset+1);
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|     }
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|   }
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| 
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|   Pass *getContainedPass(unsigned N) {
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|     assert(N < PassVector.size() && "Pass number out of range!");
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|     return static_cast<Pass *>(PassVector[N]);
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|   }
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| 
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|   PassManagerType getPassManagerType() const override {
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|     return PMT_CallGraphPassManager;
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|   }
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| 
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| private:
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|   bool RunAllPassesOnSCC(CallGraphSCC &CurSCC, CallGraph &CG,
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|                          bool &DevirtualizedCall);
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| 
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|   bool RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC,
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|                     CallGraph &CG, bool &CallGraphUpToDate,
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|                     bool &DevirtualizedCall);
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|   bool RefreshCallGraph(const CallGraphSCC &CurSCC, CallGraph &CG,
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|                         bool IsCheckingMode);
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| };
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| 
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| } // end anonymous namespace.
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| 
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| char CGPassManager::ID = 0;
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| 
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| bool CGPassManager::RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC,
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|                                  CallGraph &CG, bool &CallGraphUpToDate,
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|                                  bool &DevirtualizedCall) {
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|   bool Changed = false;
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|   PMDataManager *PM = P->getAsPMDataManager();
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|   Module &M = CG.getModule();
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| 
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|   if (!PM) {
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|     CallGraphSCCPass *CGSP = (CallGraphSCCPass *)P;
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|     if (!CallGraphUpToDate) {
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|       DevirtualizedCall |= RefreshCallGraph(CurSCC, CG, false);
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|       CallGraphUpToDate = true;
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|     }
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| 
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|     {
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|       unsigned InstrCount, SCCCount = 0;
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|       StringMap<std::pair<unsigned, unsigned>> FunctionToInstrCount;
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|       bool EmitICRemark = M.shouldEmitInstrCountChangedRemark();
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|       TimeRegion PassTimer(getPassTimer(CGSP));
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|       if (EmitICRemark)
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|         InstrCount = initSizeRemarkInfo(M, FunctionToInstrCount);
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|       Changed = CGSP->runOnSCC(CurSCC);
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| 
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|       if (EmitICRemark) {
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|         // FIXME: Add getInstructionCount to CallGraphSCC.
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|         SCCCount = M.getInstructionCount();
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|         // Is there a difference in the number of instructions in the module?
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|         if (SCCCount != InstrCount) {
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|           // Yep. Emit a remark and update InstrCount.
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|           int64_t Delta =
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|               static_cast<int64_t>(SCCCount) - static_cast<int64_t>(InstrCount);
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|           emitInstrCountChangedRemark(P, M, Delta, InstrCount,
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|                                       FunctionToInstrCount);
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|           InstrCount = SCCCount;
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|         }
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|       }
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|     }
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| 
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|     // After the CGSCCPass is done, when assertions are enabled, use
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|     // RefreshCallGraph to verify that the callgraph was correctly updated.
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| #ifndef NDEBUG
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|     if (Changed)
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|       RefreshCallGraph(CurSCC, CG, true);
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| #endif
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| 
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|     return Changed;
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|   }
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| 
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|   assert(PM->getPassManagerType() == PMT_FunctionPassManager &&
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|          "Invalid CGPassManager member");
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|   FPPassManager *FPP = (FPPassManager*)P;
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| 
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|   // Run pass P on all functions in the current SCC.
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|   for (CallGraphNode *CGN : CurSCC) {
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|     if (Function *F = CGN->getFunction()) {
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|       dumpPassInfo(P, EXECUTION_MSG, ON_FUNCTION_MSG, F->getName());
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|       {
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|         TimeRegion PassTimer(getPassTimer(FPP));
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|         Changed |= FPP->runOnFunction(*F);
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|       }
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|       F->getContext().yield();
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|     }
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|   }
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| 
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|   // The function pass(es) modified the IR, they may have clobbered the
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|   // callgraph.
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|   if (Changed && CallGraphUpToDate) {
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|     LLVM_DEBUG(dbgs() << "CGSCCPASSMGR: Pass Dirtied SCC: " << P->getPassName()
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|                       << '\n');
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|     CallGraphUpToDate = false;
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|   }
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|   return Changed;
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| }
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| 
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| /// Scan the functions in the specified CFG and resync the
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| /// callgraph with the call sites found in it.  This is used after
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| /// FunctionPasses have potentially munged the callgraph, and can be used after
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| /// CallGraphSCC passes to verify that they correctly updated the callgraph.
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| ///
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| /// This function returns true if it devirtualized an existing function call,
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| /// meaning it turned an indirect call into a direct call.  This happens when
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| /// a function pass like GVN optimizes away stuff feeding the indirect call.
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| /// This never happens in checking mode.
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| bool CGPassManager::RefreshCallGraph(const CallGraphSCC &CurSCC, CallGraph &CG,
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|                                      bool CheckingMode) {
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|   DenseMap<Value *, CallGraphNode *> Calls;
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| 
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|   LLVM_DEBUG(dbgs() << "CGSCCPASSMGR: Refreshing SCC with " << CurSCC.size()
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|                     << " nodes:\n";
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|              for (CallGraphNode *CGN
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|                   : CurSCC) CGN->dump(););
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| 
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|   bool MadeChange = false;
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|   bool DevirtualizedCall = false;
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| 
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|   // Scan all functions in the SCC.
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|   unsigned FunctionNo = 0;
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|   for (CallGraphSCC::iterator SCCIdx = CurSCC.begin(), E = CurSCC.end();
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|        SCCIdx != E; ++SCCIdx, ++FunctionNo) {
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|     CallGraphNode *CGN = *SCCIdx;
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|     Function *F = CGN->getFunction();
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|     if (!F || F->isDeclaration()) continue;
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| 
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|     // Walk the function body looking for call sites.  Sync up the call sites in
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|     // CGN with those actually in the function.
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| 
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|     // Keep track of the number of direct and indirect calls that were
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|     // invalidated and removed.
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|     unsigned NumDirectRemoved = 0, NumIndirectRemoved = 0;
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| 
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|     CallGraphNode::iterator CGNEnd = CGN->end();
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| 
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|     auto RemoveAndCheckForDone = [&](CallGraphNode::iterator I) {
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|       // Just remove the edge from the set of callees, keep track of whether
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|       // I points to the last element of the vector.
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|       bool WasLast = I + 1 == CGNEnd;
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|       CGN->removeCallEdge(I);
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| 
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|       // If I pointed to the last element of the vector, we have to bail out:
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|       // iterator checking rejects comparisons of the resultant pointer with
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|       // end.
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|       if (WasLast)
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|         return true;
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| 
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|       CGNEnd = CGN->end();
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|       return false;
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|     };
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| 
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|     // Get the set of call sites currently in the function.
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|     for (CallGraphNode::iterator I = CGN->begin(); I != CGNEnd;) {
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|       // Delete "reference" call records that do not have call instruction. We
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|       // reinsert them as needed later. However, keep them in checking mode.
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|       if (!I->first) {
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|         if (CheckingMode) {
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|           ++I;
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|           continue;
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|         }
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|         if (RemoveAndCheckForDone(I))
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|           break;
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|         continue;
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|       }
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| 
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|       // If this call site is null, then the function pass deleted the call
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|       // entirely and the WeakTrackingVH nulled it out.
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|       auto *Call = dyn_cast_or_null<CallBase>(*I->first);
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|       if (!Call ||
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|           // If we've already seen this call site, then the FunctionPass RAUW'd
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|           // one call with another, which resulted in two "uses" in the edge
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|           // list of the same call.
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|           Calls.count(Call) ||
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| 
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|           // If the call edge is not from a call or invoke, or it is a
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|           // intrinsic call, then the function pass RAUW'd a call with
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|           // another value. This can happen when constant folding happens
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|           // of well known functions etc.
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|           (Call->getCalledFunction() &&
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|            Call->getCalledFunction()->isIntrinsic() &&
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|            Intrinsic::isLeaf(Call->getCalledFunction()->getIntrinsicID()))) {
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|         assert(!CheckingMode &&
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|                "CallGraphSCCPass did not update the CallGraph correctly!");
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| 
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|         // If this was an indirect call site, count it.
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|         if (!I->second->getFunction())
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|           ++NumIndirectRemoved;
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|         else
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|           ++NumDirectRemoved;
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| 
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|         if (RemoveAndCheckForDone(I))
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|           break;
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|         continue;
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|       }
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| 
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|       assert(!Calls.count(Call) && "Call site occurs in node multiple times");
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| 
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|       if (Call) {
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|         Function *Callee = Call->getCalledFunction();
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|         // Ignore intrinsics because they're not really function calls.
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|         if (!Callee || !(Callee->isIntrinsic()))
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|           Calls.insert(std::make_pair(Call, I->second));
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|       }
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|       ++I;
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|     }
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| 
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|     // Loop over all of the instructions in the function, getting the callsites.
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|     // Keep track of the number of direct/indirect calls added.
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|     unsigned NumDirectAdded = 0, NumIndirectAdded = 0;
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| 
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|     for (BasicBlock &BB : *F)
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|       for (Instruction &I : BB) {
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|         auto *Call = dyn_cast<CallBase>(&I);
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|         if (!Call)
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|           continue;
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|         Function *Callee = Call->getCalledFunction();
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|         if (Callee && Callee->isIntrinsic())
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|           continue;
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| 
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|         // If we are not in checking mode, insert potential callback calls as
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|         // references. This is not a requirement but helps to iterate over the
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|         // functions in the right order.
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|         if (!CheckingMode) {
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|           forEachCallbackFunction(*Call, [&](Function *CB) {
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|             CGN->addCalledFunction(nullptr, CG.getOrInsertFunction(CB));
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|           });
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|         }
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| 
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|         // If this call site already existed in the callgraph, just verify it
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|         // matches up to expectations and remove it from Calls.
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|         DenseMap<Value *, CallGraphNode *>::iterator ExistingIt =
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|             Calls.find(Call);
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|         if (ExistingIt != Calls.end()) {
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|           CallGraphNode *ExistingNode = ExistingIt->second;
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| 
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|           // Remove from Calls since we have now seen it.
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|           Calls.erase(ExistingIt);
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| 
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|           // Verify that the callee is right.
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|           if (ExistingNode->getFunction() == Call->getCalledFunction())
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|             continue;
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| 
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|           // If we are in checking mode, we are not allowed to actually mutate
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|           // the callgraph.  If this is a case where we can infer that the
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|           // callgraph is less precise than it could be (e.g. an indirect call
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|           // site could be turned direct), don't reject it in checking mode, and
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|           // don't tweak it to be more precise.
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|           if (CheckingMode && Call->getCalledFunction() &&
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|               ExistingNode->getFunction() == nullptr)
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|             continue;
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| 
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|           assert(!CheckingMode &&
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|                  "CallGraphSCCPass did not update the CallGraph correctly!");
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| 
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|           // If not, we either went from a direct call to indirect, indirect to
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|           // direct, or direct to different direct.
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|           CallGraphNode *CalleeNode;
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|           if (Function *Callee = Call->getCalledFunction()) {
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|             CalleeNode = CG.getOrInsertFunction(Callee);
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|             // Keep track of whether we turned an indirect call into a direct
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|             // one.
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|             if (!ExistingNode->getFunction()) {
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|               DevirtualizedCall = true;
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|               LLVM_DEBUG(dbgs() << "  CGSCCPASSMGR: Devirtualized call to '"
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|                                 << Callee->getName() << "'\n");
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|             }
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|           } else {
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|             CalleeNode = CG.getCallsExternalNode();
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|           }
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| 
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|           // Update the edge target in CGN.
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|           CGN->replaceCallEdge(*Call, *Call, CalleeNode);
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|           MadeChange = true;
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|           continue;
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|         }
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| 
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|         assert(!CheckingMode &&
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|                "CallGraphSCCPass did not update the CallGraph correctly!");
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| 
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|         // If the call site didn't exist in the CGN yet, add it.
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|         CallGraphNode *CalleeNode;
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|         if (Function *Callee = Call->getCalledFunction()) {
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|           CalleeNode = CG.getOrInsertFunction(Callee);
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|           ++NumDirectAdded;
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|         } else {
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|           CalleeNode = CG.getCallsExternalNode();
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|           ++NumIndirectAdded;
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|         }
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| 
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|         CGN->addCalledFunction(Call, CalleeNode);
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|         MadeChange = true;
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|       }
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| 
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|     // We scanned the old callgraph node, removing invalidated call sites and
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|     // then added back newly found call sites.  One thing that can happen is
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|     // that an old indirect call site was deleted and replaced with a new direct
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|     // call.  In this case, we have devirtualized a call, and CGSCCPM would like
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|     // to iteratively optimize the new code.  Unfortunately, we don't really
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|     // have a great way to detect when this happens.  As an approximation, we
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|     // just look at whether the number of indirect calls is reduced and the
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|     // number of direct calls is increased.  There are tons of ways to fool this
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|     // (e.g. DCE'ing an indirect call and duplicating an unrelated block with a
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|     // direct call) but this is close enough.
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|     if (NumIndirectRemoved > NumIndirectAdded &&
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|         NumDirectRemoved < NumDirectAdded)
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|       DevirtualizedCall = true;
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| 
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|     // After scanning this function, if we still have entries in callsites, then
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|     // they are dangling pointers.  WeakTrackingVH should save us for this, so
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|     // abort if
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|     // this happens.
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|     assert(Calls.empty() && "Dangling pointers found in call sites map");
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| 
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|     // Periodically do an explicit clear to remove tombstones when processing
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|     // large scc's.
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|     if ((FunctionNo & 15) == 15)
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|       Calls.clear();
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|   }
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| 
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|   LLVM_DEBUG(if (MadeChange) {
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|     dbgs() << "CGSCCPASSMGR: Refreshed SCC is now:\n";
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|     for (CallGraphNode *CGN : CurSCC)
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|       CGN->dump();
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|     if (DevirtualizedCall)
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|       dbgs() << "CGSCCPASSMGR: Refresh devirtualized a call!\n";
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|   } else {
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|     dbgs() << "CGSCCPASSMGR: SCC Refresh didn't change call graph.\n";
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|   });
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|   (void)MadeChange;
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| 
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|   return DevirtualizedCall;
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| }
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| 
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| /// Execute the body of the entire pass manager on the specified SCC.
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| /// This keeps track of whether a function pass devirtualizes
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| /// any calls and returns it in DevirtualizedCall.
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| bool CGPassManager::RunAllPassesOnSCC(CallGraphSCC &CurSCC, CallGraph &CG,
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|                                       bool &DevirtualizedCall) {
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|   bool Changed = false;
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| 
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|   // Keep track of whether the callgraph is known to be up-to-date or not.
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|   // The CGSSC pass manager runs two types of passes:
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|   // CallGraphSCC Passes and other random function passes.  Because other
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|   // random function passes are not CallGraph aware, they may clobber the
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|   // call graph by introducing new calls or deleting other ones.  This flag
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|   // is set to false when we run a function pass so that we know to clean up
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|   // the callgraph when we need to run a CGSCCPass again.
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|   bool CallGraphUpToDate = true;
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| 
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|   // Run all passes on current SCC.
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|   for (unsigned PassNo = 0, e = getNumContainedPasses();
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|        PassNo != e; ++PassNo) {
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|     Pass *P = getContainedPass(PassNo);
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| 
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|     // If we're in -debug-pass=Executions mode, construct the SCC node list,
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|     // otherwise avoid constructing this string as it is expensive.
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|     if (isPassDebuggingExecutionsOrMore()) {
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|       std::string Functions;
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|   #ifndef NDEBUG
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|       raw_string_ostream OS(Functions);
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|       ListSeparator LS;
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|       for (const CallGraphNode *CGN : CurSCC) {
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|         OS << LS;
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|         CGN->print(OS);
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|       }
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|       OS.flush();
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|   #endif
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|       dumpPassInfo(P, EXECUTION_MSG, ON_CG_MSG, Functions);
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|     }
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|     dumpRequiredSet(P);
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| 
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|     initializeAnalysisImpl(P);
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| 
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| #ifdef EXPENSIVE_CHECKS
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|     uint64_t RefHash = P->structuralHash(CG.getModule());
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| #endif
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| 
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|     // Actually run this pass on the current SCC.
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|     bool LocalChanged =
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|         RunPassOnSCC(P, CurSCC, CG, CallGraphUpToDate, DevirtualizedCall);
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| 
 | |
|     Changed |= LocalChanged;
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| 
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| #ifdef EXPENSIVE_CHECKS
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|     if (!LocalChanged && (RefHash != P->structuralHash(CG.getModule()))) {
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|       llvm::errs() << "Pass modifies its input and doesn't report it: "
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|                    << P->getPassName() << "\n";
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|       llvm_unreachable("Pass modifies its input and doesn't report it");
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|     }
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| #endif
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|     if (LocalChanged)
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|       dumpPassInfo(P, MODIFICATION_MSG, ON_CG_MSG, "");
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|     dumpPreservedSet(P);
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| 
 | |
|     verifyPreservedAnalysis(P);
 | |
|     if (LocalChanged)
 | |
|       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++ < MaxDevirtIterations && DevirtualizedCall);
 | |
| 
 | |
|     if (DevirtualizedCall)
 | |
|       LLVM_DEBUG(dbgs() << "  CGSCCPASSMGR: Stopped iteration after "
 | |
|                         << Iteration
 | |
|                         << " times, due to -max-devirt-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;
 | |
|     if (New)
 | |
|       Nodes[i] = New;
 | |
|     else
 | |
|       Nodes.erase(Nodes.begin() + i);
 | |
|     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);
 | |
| }
 | |
| 
 | |
| void CallGraphSCC::DeleteNode(CallGraphNode *Old) {
 | |
|   ReplaceNode(Old, /*New=*/nullptr);
 | |
| }
 | |
| 
 | |
| //===----------------------------------------------------------------------===//
 | |
| // 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 (";
 | |
|   ListSeparator LS;
 | |
|   for (CallGraphNode *CGN : SCC) {
 | |
|     Desc += LS;
 | |
|     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)
 |