greedy_node_cov.h

/*
 * SPDX-FileCopyrightText: 2023 The P4 Language Consortium
 *
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef BACKENDS_P4TOOLS_MODULES_TESTGEN_CORE_SYMBOLIC_EXECUTOR_GREEDY_NODE_COV_H_
#define BACKENDS_P4TOOLS_MODULES_TESTGEN_CORE_SYMBOLIC_EXECUTOR_GREEDY_NODE_COV_H_
 
#include <cstdint>
#include <optional>
#include <vector>
 
#include "ir/solver.h"
#include "midend/coverage.h"
 
#include "backends/p4tools/modules/testgen/core/program_info.h"
#include "backends/p4tools/modules/testgen/core/symbolic_executor/symbolic_executor.h"
 
namespace P4::P4Tools::P4Testgen {

class GreedyNodeSelection : public SymbolicExecutor {
 public:
    void runImpl(const Callback &callBack, ExecutionStateReference state) override;

    GreedyNodeSelection(AbstractSolver &solver, const ProgramInfo &programInfo);
 
 private:
    uint64_t stepsWithoutTest = 0;

    static const uint64_t MAX_STEPS_WITHOUT_TEST = 1000;

    std::vector<Branch> potentialBranches;

    // Each element on this vector represents a set of alternative choices that could have been
    std::vector<Branch> unexploredBranches;

    static std::optional<SymbolicExecutor::Branch> popPotentialBranch(
        const P4::Coverage::CoverageSet &coverednodes,
        std::vector<SymbolicExecutor::Branch> &candidateBranches);

    [[nodiscard]] std::optional<ExecutionStateReference> pickSuccessor(StepResult successors);
};
 
}  // namespace P4::P4Tools::P4Testgen
 
#endif /* BACKENDS_P4TOOLS_MODULES_TESTGEN_CORE_SYMBOLIC_EXECUTOR_GREEDY_NODE_COV_H_ */