//===-- ColossusCoissueUtil.h - Utilities for coissue -----------*- C++ -*-===//
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//===----------------------------------------------------------------------===//

#include "MCTargetDesc/ColossusMCInstrInfo.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunction.h"

namespace llvm {
namespace Colossus {

// Two instructions can be coissued when:
// (TSFlags >> 25) & 1 is true on both
// The two instructions are on different lanes
// There is no overlap in destination registers
// The M side is first, or they can be swapped without semantic change

class CoissueUtil {
  std::unique_ptr<MCInstrInfo> MII;
  int getLaneWithSigil(MachineInstr *) const;

public:
  CoissueUtil();
  bool isControl(MachineInstr *) const;
  bool isSystem(MachineInstr *) const;
  bool canCoissue(MachineInstr *) const;

  bool canBundleWithNextInstr(MachineFunction::iterator,
                              MachineBasicBlock::instr_iterator) const;

  MachineBasicBlock::instr_iterator
      findNextNonMetaInstr(MachineFunction::iterator MFI,
                           MachineBasicBlock::instr_iterator first) const;

  MachineBasicBlock::instr_iterator
  findNextNonMetaInstr(MachineBasicBlock::instr_iterator first,
                       MachineBasicBlock::instr_iterator last) const;

  MachineBasicBlock::instr_iterator
      bundleWithNop(MachineFunction::iterator,
                    MachineBasicBlock::instr_iterator) const;

  MachineBasicBlock::instr_iterator
      bundleWithNextInstr(MachineFunction::iterator,
                          MachineBasicBlock::instr_iterator) const;

  Optional<MachineBasicBlock::instr_iterator>
      queryNextInstrToBundle(MachineFunction::iterator MFI,
                             MachineBasicBlock::instr_iterator first) const;

  Optional<MachineBasicBlock::instr_iterator>
      queryNextInstrToBundle(MachineBasicBlock::instr_iterator first,
                             MachineBasicBlock::instr_iterator last) const;
};

} // namespace Colossus
} // namespace llvm