//===- CFGReachabilityAnalysis.h - Basic reachability analysis --*- 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 defines a flow-sensitive, (mostly) path-insensitive reachability
// analysis based on Clang's CFGs. Clients can query if a given basic block
// is reachable within the CFG.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_ANALYSIS_ANALYSES_CFGREACHABILITYANALYSIS_H
#define LLVM_CLANG_ANALYSIS_ANALYSES_CFGREACHABILITYANALYSIS_H
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/DenseMap.h"
namespace clang {
class CFG;
class CFGBlock;
// A class that performs reachability queries for CFGBlocks. Several internal
// checks in this checker require reachability information. The requests all
// tend to have a common destination, so we lazily do a predecessor search
// from the destination node and cache the results to prevent work
// duplication.
class CFGReverseBlockReachabilityAnalysis {
using ReachableSet = llvm::BitVector;
using ReachableMap = llvm::DenseMap<unsigned, ReachableSet>;
ReachableSet analyzed;
ReachableMap reachable;
public:
CFGReverseBlockReachabilityAnalysis(const CFG &cfg);
/// Returns true if the block 'Dst' can be reached from block 'Src'.
bool isReachable(const CFGBlock *Src, const CFGBlock *Dst);
private:
void mapReachability(const CFGBlock *Dst);
};
} // namespace clang
#endif // LLVM_CLANG_ANALYSIS_ANALYSES_CFGREACHABILITYANALYSIS_H