peephole_ll.h

// Copyright (c) 2021-2023, David H. Hovemeyer <david.hovemeyer@gmail.com>
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
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// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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#ifndef PEEPHOLE_LL_H
#define PEEPHOLE_LL_H
 
#include <deque>
#include <vector>
#include "live_mregs.h"
#include "cfg_transform.h"
 
class PeepholeLowLevel : public ControlFlowGraphTransform {
private:
  // liveness info about machine registers
  LiveMregs m_live_mregs;
 
  // window of instructions from the original InstructionSequence
  std::deque<Instruction *> m_window;
 
  // number of patterns matched/transformations applied
  int m_num_matched;
 
public:
  PeepholeLowLevel(const std::shared_ptr<ControlFlowGraph> &cfg);
  virtual ~PeepholeLowLevel();
 
  virtual std::shared_ptr<InstructionSequence> transform_basic_block(std::shared_ptr<InstructionSequence> orig_bb);
 
  int get_num_matched() const { return m_num_matched; }
 
private:
  void emit_earliest_in_window(InstructionSequence *result_iseq);
};
 
#endif // PEEPHOLE_LL_H