(MDP-LTL) SparseMdpPrctlHelper: computeSurelyAcceptingPmaxStates

5 years ago · 615b2b5399
2 changed files with 119 additions and 0 deletions
--- a/src/storm/modelchecker/prctl/helper/SparseMdpPrctlHelper.cpp
+++ b/src/storm/modelchecker/prctl/helper/SparseMdpPrctlHelper.cpp
@ -745,6 +745,112 @@ namespace storm {
                    return result;
                }
            }
+
+            template<typename ValueType>
+            storm::storage::BitVector SparseMdpPrctlHelper<ValueType>::computeSurelyAcceptingPmaxStates(automata::AcceptanceCondition const& acceptance, storm::storage::SparseMatrix<ValueType> const& transitionMatrix, storm::storage::SparseMatrix<ValueType> const& backwardTransitions) {
+                STORM_LOG_INFO("Computing accepting states for acceptance condition " << *acceptance.getAcceptanceExpression());
+                std::cout << transitionMatrix.getRowGroupCount() << std::endl;
+                if (acceptance.getAcceptanceExpression()->isTRUE()) {
+                    STORM_LOG_INFO(" TRUE -> all states accepting (assumes no deadlock in the model)");
+                    return storm::storage::BitVector(transitionMatrix.getRowGroupCount(), true);
+                } else if (acceptance.getAcceptanceExpression()->isFALSE()) {
+                    STORM_LOG_INFO(" FALSE -> all states rejecting");
+                    return storm::storage::BitVector(transitionMatrix.getRowGroupCount(), false);
+                }
+
+                std::vector<std::vector<automata::AcceptanceCondition::acceptance_expr::ptr>> dnf = acceptance.extractFromDNF();
+
+                storm::storage::BitVector acceptingStates(transitionMatrix.getRowGroupCount(), false);
+
+                std::size_t i = 0;
+                for (auto const& conjunction : dnf) {
+                    // determine the set of states of the subMDP that can satisfy the condition
+                    //  => remove all states that would violate Fins in the conjunction
+                    storm::storage::BitVector allowed(transitionMatrix.getRowGroupCount(), true);
+
+                    STORM_LOG_INFO("Handle conjunction " << i);
+
+                    for (auto const& literal : conjunction) {
+                        STORM_LOG_INFO(" " << *literal);
+                        if (literal->isTRUE()) {
+                            // skip
+                        } else if (literal->isFALSE()) {
+                            allowed.clear();
+                            break;
+                        } else if (literal->isAtom()) {
+                            const cpphoafparser::AtomAcceptance& atom = literal->getAtom();
+                            if (atom.getType() == cpphoafparser::AtomAcceptance::TEMPORAL_FIN) {
+                                // only deal with FIN, ignore INF here
+                                const storm::storage::BitVector& accSet = acceptance.getAcceptanceSet(atom.getAcceptanceSet());
+                                if (atom.isNegated()) {
+                                    // allowed = allowed \ ~accSet = allowed & accSet
+                                    allowed &= accSet;
+                                } else {
+                                    // allowed = allowed \ accSet = allowed & ~accSet
+                                    allowed &= ~accSet;
+                                }
+                            }
+                        }
+                    }
+
+                    if (allowed.empty()) {
+                        // skip
+                        continue;
+                    }
+
+                    STORM_LOG_INFO(" Allowed states: " << allowed);
+
+                    // compute MECs in the allowed fragment
+                    storm::storage::MaximalEndComponentDecomposition<ValueType> mecs(transitionMatrix, backwardTransitions, allowed);
+                    for (const auto& mec : mecs) {
+                        STORM_LOG_INFO("Inspect MEC: " << mec);
+
+                        bool accepting = true;
+                        for (auto const& literal : conjunction) {
+                            if (literal->isTRUE()) {
+                                // skip
+                            } else if (literal->isFALSE()) {
+                                accepting = false;
+                                break;
+                            } else if (literal->isAtom()) {
+                                const cpphoafparser::AtomAcceptance& atom = literal->getAtom();
+                                const storm::storage::BitVector& accSet = acceptance.getAcceptanceSet(atom.getAcceptanceSet());
+                                if (atom.getType() == cpphoafparser::AtomAcceptance::TEMPORAL_INF) {
+                                    if (atom.isNegated()) {
+                                        STORM_LOG_INFO("Checking against " << ~accSet);
+                                        if (!mec.containsAnyState(~accSet)) {
+                                            STORM_LOG_INFO("  -> not satisfied");
+                                            accepting = false;
+                                            break;
+                                        }
+                                    } else {
+                                        STORM_LOG_INFO("Checking against " << accSet);
+                                        if (!mec.containsAnyState(accSet)) {
+                                            STORM_LOG_INFO("  -> not satisfied");
+                                            accepting = false;
+                                            break;
+                                        }
+                                    }
+                                } else if (atom.getType() == cpphoafparser::AtomAcceptance::TEMPORAL_FIN) {
+                                    // do only sanity checks here
+                                    STORM_LOG_ASSERT(atom.isNegated() ? !mec.containsAnyState(~accSet) : !mec.containsAnyState(accSet), "MEC contains Fin-states, which should have been removed");
+                                }
+                            }
+                        }
+
+                        if (accepting) {
+                            STORM_LOG_INFO("MEC is accepting");
+                            for (auto const& stateChoicePair : mec) {
+                                acceptingStates.set(stateChoicePair.first);
+                            }
+                        }
+
+                    }
+                }
+
+                STORM_LOG_INFO("Accepting states: " << acceptingStates);
+                return acceptingStates;
+            }
            
            template<typename ValueType>
            template<typename RewardModelType>
--- a/src/storm/modelchecker/prctl/helper/SparseMdpPrctlHelper.h
+++ b/src/storm/modelchecker/prctl/helper/SparseMdpPrctlHelper.h
@ -10,6 +10,8 @@
 #include "storm/modelchecker/prctl/helper/rewardbounded/MultiDimensionalRewardUnfolding.h"
 #include "MDPModelCheckingHelperReturnType.h"

+#include "storm/automata/AcceptanceCondition.h"
+
 #include "storm/utility/solver.h"
 #include "storm/solver/SolveGoal.h"

@ -47,6 +49,17 @@ namespace storm {
                
                static MDPSparseModelCheckingHelperReturnType<ValueType> computeGloballyProbabilities(Environment const& env, storm::solver::SolveGoal<ValueType>&& goal, storm::storage::SparseMatrix<ValueType> const& transitionMatrix, storm::storage::SparseMatrix<ValueType> const& backwardTransitions, storm::storage::BitVector const& psiStates, bool qualitative, bool produceScheduler, bool useMecBasedTechnique = false);
                
+                /*!
+                 * Compute a set S of states that admit a probability 1 strategy of satisfying the given acceptance conditon.
+                 * More precisely, let
+                 *   accEC be the set of states that are contained in end components that satisfy the acceptance condition
+                 *  and let
+                 *   P1acc be the set of states that satisfy Pmax=1[ F accEC ].
+                 * This function then computes a set that contains accEC and is contained by P1acc.
+                 * However, if the acceptance condition consists of 'true', the whole state space can be returned.
+                 */
+                static storm::storage::BitVector computeSurelyAcceptingPmaxStates(automata::AcceptanceCondition const& acceptance, storm::storage::SparseMatrix<ValueType> const& transitionMatrix, storm::storage::SparseMatrix<ValueType> const& backwardTransitions);
+
                template<typename RewardModelType>
                static std::vector<ValueType> computeInstantaneousRewards(Environment const& env, storm::solver::SolveGoal<ValueType>&& goal, storm::storage::SparseMatrix<ValueType> const& transitionMatrix, RewardModelType const& rewardModel, uint_fast64_t stepCount);