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//===-------------- llvm/CodeGen/ProcessImplicitDefs.h ----------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//


#ifndef LLVM_CODEGEN_PROCESSIMPLICITDEFS_H
#define LLVM_CODEGEN_PROCESSIMPLICITDEFS_H

#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/ADT/SmallSet.h"

namespace llvm {

  class MachineInstr;
  class TargetInstrInfo;
  class TargetRegisterInfo;
  class MachineRegisterInfo;
  class LiveVariables;

  /// Process IMPLICIT_DEF instructions and make sure there is one implicit_def
  /// for each use. Add isUndef marker to implicit_def defs and their uses.
  class ProcessImplicitDefs : public MachineFunctionPass {
    const TargetInstrInfo *TII;
    const TargetRegisterInfo *TRI;
    MachineRegisterInfo *MRI;
    LiveVariables *LV;

    bool CanTurnIntoImplicitDef(MachineInstr *MI, unsigned Reg,
                                unsigned OpIdx,
                                SmallSet<unsigned, 8> &ImpDefRegs);

  public:
    static char ID;

    ProcessImplicitDefs() : MachineFunctionPass(ID) {
      initializeProcessImplicitDefsPass(*PassRegistry::getPassRegistry());
    }

    virtual void getAnalysisUsage(AnalysisUsage &au) const;

    virtual bool runOnMachineFunction(MachineFunction &fn);
  };

}

#endif // LLVM_CODEGEN_PROCESSIMPLICITDEFS_H