llvm/llvm/include/llvm/CodeGen/LiveRegMatrix.h

//===- LiveRegMatrix.h - Track register interference ----------*- 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
//
//===----------------------------------------------------------------------===//
//
// The LiveRegMatrix analysis pass keeps track of virtual register interference
// along two dimensions: Slot indexes and register units. The matrix is used by
// register allocators to ensure that no interfering virtual registers get
// assigned to overlapping physical registers.
//
// Register units are defined in MCRegisterInfo.h, they represent the smallest
// unit of interference when dealing with overlapping physical registers. The
// LiveRegMatrix is represented as a LiveIntervalUnion per register unit. When
// a virtual register is assigned to a physical register, the live range for
// the virtual register is inserted into the LiveIntervalUnion for each regunit
// in the physreg.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CODEGEN_LIVEREGMATRIX_H
#define LLVM_CODEGEN_LIVEREGMATRIX_H

#include "llvm/ADT/BitVector.h"
#include "llvm/CodeGen/LiveIntervalUnion.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include <memory>

namespace llvm {

class AnalysisUsage;
class LiveInterval;
class LiveIntervals;
class MachineFunction;
class TargetRegisterInfo;
class VirtRegMap;

class LiveRegMatrix : public MachineFunctionPass { … };

} // end namespace llvm

#endif // LLVM_CODEGEN_LIVEREGMATRIX_H