//===-- AVRSubtarget.h - Define Subtarget for the AVR -----------*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This file declares the AVR specific subclass of TargetSubtargetInfo.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_AVR_SUBTARGET_H
#define LLVM_AVR_SUBTARGET_H

#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/Target/TargetMachine.h"

#include "AVRFrameLowering.h"
#include "AVRISelLowering.h"
#include "AVRInstrInfo.h"
#include "AVRSelectionDAGInfo.h"
#include "MCTargetDesc/AVRMCTargetDesc.h"

#define GET_SUBTARGETINFO_HEADER
#include "AVRGenSubtargetInfo.inc"

namespace llvm {

/// A specific AVR target MCU.
class AVRSubtarget : public AVRGenSubtargetInfo {
public:
  //! Creates an AVR subtarget.
  //! \param TT  The target triple.
  //! \param CPU The CPU to target.
  //! \param FS  The feature string.
  //! \param TM  The target machine.
  AVRSubtarget(const Triple &TT, const std::string &CPU, const std::string &FS,
               const AVRTargetMachine &TM);

  const AVRInstrInfo *getInstrInfo() const override { return &InstrInfo; }
  const TargetFrameLowering *getFrameLowering() const override {
    return &FrameLowering;
  }
  const AVRTargetLowering *getTargetLowering() const override {
    return &TLInfo;
  }
  const AVRSelectionDAGInfo *getSelectionDAGInfo() const override {
    return &TSInfo;
  }
  const AVRRegisterInfo *getRegisterInfo() const override {
    return &InstrInfo.getRegisterInfo();
  }

  /// Parses a subtarget feature string, setting appropriate options.
  /// \note Definition of function is auto generated by `tblgen`.
  void ParseSubtargetFeatures(StringRef CPU, StringRef TuneCPU, StringRef FS);

  AVRSubtarget &initializeSubtargetDependencies(StringRef CPU, StringRef FS,
                                                const TargetMachine &TM);

  // Subtarget feature getters.
  // See AVR.td for details.
  bool hasSRAM() const { return m_hasSRAM; }
  bool hasJMPCALL() const { return m_hasJMPCALL; }
  bool hasIJMPCALL() const { return m_hasIJMPCALL; }
  bool hasEIJMPCALL() const { return m_hasEIJMPCALL; }
  bool hasADDSUBIW() const { return m_hasADDSUBIW; }
  bool hasSmallStack() const { return m_hasSmallStack; }
  bool hasMOVW() const { return m_hasMOVW; }
  bool hasLPM() const { return m_hasLPM; }
  bool hasLPMX() const { return m_hasLPMX; }
  bool hasELPM() const { return m_hasELPM; }
  bool hasELPMX() const { return m_hasELPMX; }
  bool hasSPM() const { return m_hasSPM; }
  bool hasSPMX() const { return m_hasSPMX; }
  bool hasDES() const { return m_hasDES; }
  bool supportsRMW() const { return m_supportsRMW; }
  bool supportsMultiplication() const { return m_supportsMultiplication; }
  bool hasBREAK() const { return m_hasBREAK; }
  bool hasTinyEncoding() const { return m_hasTinyEncoding; }
  bool hasMemMappedGPR() const { return m_hasMemMappedGPR; }
  bool hasLowByteFirst() const { return m_hasLowByteFirst; }

  uint8_t getIORegisterOffset() const { return hasMemMappedGPR() ? 0x20 : 0x0; }

  bool enableSubRegLiveness() const override { return true; }

  /// Gets the ELF architecture for the e_flags field
  /// of an ELF object file.
  unsigned getELFArch() const {
    assert(ELFArch != 0 &&
           "every device must have an associate ELF architecture");
    return ELFArch;
  }

  /// Get I/O register addresses.
  int getIORegRAMPZ() const { return hasELPM() ? 0x3b : -1; }
  int getIORegEIND() const { return hasEIJMPCALL() ? 0x3c : -1; }
  int getIORegSPL() const { return 0x3d; }
  int getIORegSPH() const { return hasSmallStack() ? -1 : 0x3e; }
  int getIORegSREG() const { return 0x3f; }

  /// Get GPR aliases.
  int getRegTmpIndex() const { return hasTinyEncoding() ? 16 : 0; }
  int getRegZeroIndex() const { return hasTinyEncoding() ? 17 : 1; }

  Register getTmpRegister() const {
    return hasTinyEncoding() ? AVR::R16 : AVR::R0;
  }
  Register getZeroRegister() const {
    return hasTinyEncoding() ? AVR::R17 : AVR::R1;
  }

private:
  /// The ELF e_flags architecture.
  unsigned ELFArch = 0;

  // Subtarget feature settings
  // See AVR.td for details.
  bool m_hasSRAM = false;
  bool m_hasJMPCALL = false;
  bool m_hasIJMPCALL = false;
  bool m_hasEIJMPCALL = false;
  bool m_hasADDSUBIW = false;
  bool m_hasSmallStack = false;
  bool m_hasMOVW = false;
  bool m_hasLPM = false;
  bool m_hasLPMX = false;
  bool m_hasELPM = false;
  bool m_hasELPMX = false;
  bool m_hasSPM = false;
  bool m_hasSPMX = false;
  bool m_hasDES = false;
  bool m_supportsRMW = false;
  bool m_supportsMultiplication = false;
  bool m_hasBREAK = false;
  bool m_hasTinyEncoding = false;
  bool m_hasLowByteFirst = false;
  bool m_hasMemMappedGPR = false;

  // Dummy member, used by FeatureSet's. We cannot have a SubtargetFeature with
  // no variable, so we instead bind pseudo features to this variable.
  bool m_FeatureSetDummy = false;

  AVRInstrInfo InstrInfo;
  AVRFrameLowering FrameLowering;
  AVRTargetLowering TLInfo;
  AVRSelectionDAGInfo TSInfo;
};

} // end namespace llvm

#endif // LLVM_AVR_SUBTARGET_H