//===- LazyLiveness.h - Lazy, CFG-invariant liveness information ----------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This pass implements a lazy liveness analysis as per "Fast Liveness Checking // for SSA-form Programs," by Boissinot, et al. // //===----------------------------------------------------------------------===// #ifndef LLVM_CODEGEN_LAZYLIVENESS_H #define LLVM_CODEGEN_LAZYLIVENESS_H #include "llvm/CodeGen/MachineFunctionPass.h" #include "llvm/CodeGen/MachineDominators.h" #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/DenseSet.h" #include "llvm/ADT/SparseBitVector.h" #include <vector> namespace llvm { class MachineRegisterInfo; class LazyLiveness : public MachineFunctionPass { public: static char ID; // Pass identification, replacement for typeid LazyLiveness() : MachineFunctionPass(&ID) { } void getAnalysisUsage(AnalysisUsage &AU) const { AU.setPreservesAll(); AU.addRequired<MachineDominatorTree>(); } bool runOnMachineFunction(MachineFunction &mf); bool vregLiveIntoMBB(unsigned vreg, MachineBasicBlock* MBB); private: void computeBackedgeChain(MachineFunction& mf, MachineBasicBlock* MBB); typedef std::pair<MachineBasicBlock*, MachineBasicBlock*> edge_t; MachineRegisterInfo* MRI; DenseMap<MachineBasicBlock*, unsigned> preorder; std::vector<MachineBasicBlock*> rev_preorder; DenseMap<MachineBasicBlock*, SparseBitVector<128> > rv; DenseMap<MachineBasicBlock*, SparseBitVector<128> > tv; DenseSet<edge_t> backedges; SparseBitVector<128> backedge_source; SparseBitVector<128> backedge_target; SparseBitVector<128> calculated; }; } #endif