MCLFIRewriter.h

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//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file declares the MCLFIRewriter class, an abstract class that
/// encapsulates the rewriting logic for MCInsts.
///
//===----------------------------------------------------------------------===//
 
#ifndef LLVM_MC_MCLFIREWRITER_H
#define LLVM_MC_MCLFIREWRITER_H
 
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/Support/Compiler.h"
 
namespace llvm {
class MCContext;
class MCInst;
class MCSubtargetInfo;
class MCStreamer;
class MCSymbol;
 
class MCLFIRewriter {
private:
  MCContext &Ctx;
 
protected:
  bool Enabled = true;
  std::unique_ptr<MCInstrInfo> InstInfo;
  std::unique_ptr<MCRegisterInfo> RegInfo;
 
public:
  MCLFIRewriter(MCContext &Ctx, std::unique_ptr<MCRegisterInfo> &&RI,
                std::unique_ptr<MCInstrInfo> &&II)
      : Ctx(Ctx), InstInfo(std::move(II)), RegInfo(std::move(RI)) {}
 
  LLVM_ABI void error(const MCInst &Inst, const char Msg[]);
 
  void disable() { Enabled = false; }
  void enable() { Enabled = true; }
 
  LLVM_ABI bool isCall(const MCInst &Inst) const;
  LLVM_ABI bool isBranch(const MCInst &Inst) const;
  LLVM_ABI bool isIndirectBranch(const MCInst &Inst) const;
  LLVM_ABI bool isReturn(const MCInst &Inst) const;
 
  LLVM_ABI bool mayLoad(const MCInst &Inst) const;
  LLVM_ABI bool mayStore(const MCInst &Inst) const;
 
  LLVM_ABI bool mayModifyRegister(const MCInst &Inst, MCRegister Reg) const;
 
  virtual ~MCLFIRewriter() = default;
  virtual bool rewriteInst(const MCInst &Inst, MCStreamer &Out,
                           const MCSubtargetInfo &STI) = 0;
 
  // Called when a label is emitted. Used for optimizations that require
  // information about jump targets, such as guard elimination.
  virtual void onLabel(const MCSymbol *Symbol) {}
};
 
} // namespace llvm
#endif