//===- ReachableCode.h -----------------------------------------*- 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

//

//===----------------------------------------------------------------------===//

//

// A flow-sensitive, path-insensitive analysis of unreachable code.

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_ANALYSIS_ANALYSES_REACHABLECODE_H

#define LLVM_CLANG_ANALYSIS_ANALYSES_REACHABLECODE_H

#include "clang/Basic/SourceLocation.h"

//===----------------------------------------------------------------------===//

// Forward declarations.

//===----------------------------------------------------------------------===//

namespace llvm {

  class BitVector;

}

namespace clang {

  class AnalysisDeclContext;

  class CFGBlock;

  class Preprocessor;

}

//===----------------------------------------------------------------------===//

// API.

//===----------------------------------------------------------------------===//

namespace clang {

namespace reachable_code {

/// Classifications of unreachable code.

enum UnreachableKind {

  UK_Return,

  UK_Break,

  UK_Loop_Increment,

  UK_Other

};

class Callback {

  virtual void anchor();

public:

  virtual ~Callback() {}

  virtual void HandleUnreachable(UnreachableKind UK,

                                 SourceLocation L,

                                 SourceRange ConditionVal,

                                 SourceRange R1,

                                 SourceRange R2) = 0;

};

/// ScanReachableFromBlock - Mark all blocks reachable from Start.

/// Returns the total number of blocks that were marked reachable.

unsigned ScanReachableFromBlock(const CFGBlock *Start,

                                llvm::BitVector &Reachable);

void FindUnreachableCode(AnalysisDeclContext &AC, Preprocessor &PP,

                         Callback &CB);

}} // end namespace clang::reachable_code

#endif