sp
/
tempest
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
Browse Source

Added SMT function to calculate lower bound for number of DFT failures needed for failure of TLE

main
Alexander Bork 7 years ago
parent
efcff20017
commit
d06cf59eba
4 changed files with 113 additions and 17 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 7
      src/storm-dft/api/storm-dft.cpp
  2. 55
      src/storm-dft/modelchecker/dft/DFTASFChecker.cpp
  3. 49
      src/storm-dft/modelchecker/dft/DFTASFChecker.h
  4. 19
      src/test/storm-dft/api/DftModelCheckerTest.cpp

7
src/storm-dft/api/storm-dft.cpp
View File

@ -51,11 +51,11 @@ namespace storm {
std::vector<storm::solver::SmtSolver::CheckResult> results;
results.push_back(smtChecker.checkTleNeverFailedQuery());
uint64_t lower_bound = smtChecker.getLeastFailureBound();
if (printOutput) {
// TODO add suitable output function, maybe add query descriptions for better readability
//TODO add suitable output function, maybe add query descriptions for better readability
for (size_t i = 0; i < results.size(); ++i) {
std::string tmp = "unknonwn";
std::string tmp = "unknown";
if (results.at(i) == storm::solver::SmtSolver::CheckResult::Sat) {
tmp = "SAT";
} else if (results.at(i) == storm::solver::SmtSolver::CheckResult::Unsat) {
@ -63,6 +63,7 @@ namespace storm {
}
std::cout << "Query " << std::to_string(i) << " : " << tmp << std::endl;
}
std::cout << "Lower bound: " << std::to_string(lower_bound) << std::endl;
}
return results;
}

55
src/storm-dft/modelchecker/dft/DFTASFChecker.cpp
View File

@ -459,19 +459,66 @@ namespace storm {
}
storm::solver::SmtSolver::CheckResult DFTASFChecker::checkTleNeverFailedQuery() {
STORM_LOG_ERROR_COND(!solver, "SMT Solver was not initialized, call toSolver() before checking queries");
// STORM_LOG_ERROR_COND(!solver, "SMT Solver was not initialized, call toSolver() before checking queries");
// Set backtracking marker to check several properties without reconstructing DFT encoding
solver->push();
// Constraint that toplevel element will not fail (part of constraint 13)
std::shared_ptr<SmtConstraint> tleNeverFailedConstr = std::make_shared<IsConstantValue>(
timePointVariables.at(dft.getTopLevelIndex()), notFailed);
solver->add(tleNeverFailedConstr->toExpression(varNames,
std::make_shared<storm::expressions::ExpressionManager>(
solver->getManager())));
std::shared_ptr<storm::expressions::ExpressionManager> manager = solver->getManager().getSharedPointer();
solver->add(tleNeverFailedConstr->toExpression(varNames, manager));
storm::solver::SmtSolver::CheckResult res = solver->check();
solver->pop();
return res;
}
storm::solver::SmtSolver::CheckResult DFTASFChecker::checkTleFailsWithLeq(uint64_t bound) {
//STORM_LOG_ERROR_COND(!solver, "SMT Solver was not initialized, call toSolver() before checking queries");
// Set backtracking marker to check several properties without reconstructing DFT encoding
solver->push();
// Constraint that toplevel element can fail with less or equal 'bound' failures
std::shared_ptr<SmtConstraint> tleNeverFailedConstr = std::make_shared<IsLessEqualConstant>(
timePointVariables.at(dft.getTopLevelIndex()), bound);
std::shared_ptr<storm::expressions::ExpressionManager> manager = solver->getManager().getSharedPointer();
solver->add(tleNeverFailedConstr->toExpression(varNames, manager));
storm::solver::SmtSolver::CheckResult res = solver->check();
solver->pop();
return res;
}
void DFTASFChecker::setSolverTimeout(uint_fast64_t milliseconds) {
if (!solver) {
STORM_LOG_WARN("SMT Solver was not initialized, timeout setting ignored");
} else {
solver->setTimeout(milliseconds);
}
}
void DFTASFChecker::unsetSolverTimeout() {
if (!solver) {
STORM_LOG_WARN("SMT Solver was not initialized, timeout unsetting ignored");
} else {
solver->unsetTimeout();
}
}
uint64_t DFTASFChecker::getLeastFailureBound() {
//STORM_LOG_ERROR_COND(!solver, "SMT Solver was not initialized, call toSolver() before checking queries");
uint64_t bound = 0;
while (bound < notFailed) {
setSolverTimeout(10000);
storm::solver::SmtSolver::CheckResult tmp_res = checkTleFailsWithLeq(bound);
unsetSolverTimeout();
if (tmp_res == storm::solver::SmtSolver::CheckResult::Sat ||
tmp_res == storm::solver::SmtSolver::CheckResult::Unknown) {
return bound;
}
++bound;
}
return bound;
}
}
}

49
src/storm-dft/modelchecker/dft/DFTASFChecker.h
View File

@ -37,7 +37,44 @@ namespace storm {
void convert();
void toFile(std::string const&);
/**
* Generates a new solver instance and prepares it for SMT checking of the DFT. Needs to be called before all queries to the solver
*/
void toSolver();
/**
* Check if the TLE of the DFT never fails
*
* @return "Sat" if TLE never fails, "Unsat" if it does, otherwise "Unknown"
*/
storm::solver::SmtSolver::CheckResult checkTleNeverFailedQuery();
/**
* Check if there exists a sequence of BE failures of given length such that the TLE of the DFT fails
*
* @param bound the length of the sequene
* @return "Sat" if such a sequence exists, "Unsat" if it does not, otherwise "Unknown"
*/
storm::solver::SmtSolver::CheckResult checkTleFailsWithLeq(uint64_t bound);
/**
* Get the minimal number of BEs necessary for the TLE to fail
*
* @return the minimal number
*/
uint64_t getLeastFailureBound();
/**
* Set the timeout of the solver
*
* @param milliseconds the timeout in milliseconds
*/
void setSolverTimeout(uint_fast64_t milliseconds);
/**
* Unset the timeout for the solver
*/
void unsetSolverTimeout();
private:
uint64_t getClaimVariableIndex(uint64_t spareIndex, uint64_t childIndex) const;
@ -72,7 +109,6 @@ namespace storm {
/**
* Add constraints encoding VOT gates.
*/
void generateVotConstraint(size_t i, std::vector<uint64_t> childVarIndices,
std::shared_ptr<storm::storage::DFTElement<ValueType> const> element);
@ -107,7 +143,7 @@ namespace storm {
/**
* Add constraints encoding claiming rules.
* This corresponds to constraint (8) and addition
*/
*/
void addClaimingConstraints();
/**
@ -115,16 +151,9 @@ namespace storm {
* This corresponds to constraints (9), (10) and (11)
*/
void addMarkovianConstraints();
/**
* Check if the TLE of the DFT never fails
*
* @return "Sat" if TLE never fails, "Unsat" if it does, otherwise "Unknown"
*/
storm::solver::SmtSolver::CheckResult checkTleNeverFailedQuery();
storm::storage::DFT<ValueType> const& dft;
std::shared_ptr<storm::solver::SmtSolver> solver = 0;
std::shared_ptr<storm::solver::SmtSolver> solver = NULL;
std::vector<std::string> varNames;
std::unordered_map<uint64_t, uint64_t> timePointVariables;
std::vector<std::shared_ptr<SmtConstraint>> constraints;

19
src/test/storm-dft/api/DftModelCheckerTest.cpp
View File

@ -2,6 +2,7 @@
#include "storm-config.h"
#include "storm-dft/api/storm-dft.h"
#include "storm-dft/modelchecker/dft/DFTASFChecker.h"
#include "storm-parsers/api/storm-parsers.h"
namespace {
@ -71,6 +72,17 @@ namespace {
return boost::get<double>(results[0]);
}
storm::solver::SmtSolver::CheckResult analyzeSMT(std::string const &file) {
std::shared_ptr<storm::storage::DFT<double>> dft = storm::api::loadDFTGalileoFile<double>(file);
EXPECT_TRUE(storm::api::isWellFormed(*dft));
storm::modelchecker::DFTASFChecker smtChecker(*dft);
smtChecker.convert();
smtChecker.toSolver();
std::vector<storm::solver::SmtSolver::CheckResult> results;
return smtChecker.checkTleNeverFailedQuery();
}
double analyzeReliability(std::string const &file, double bound) {
std::shared_ptr<storm::storage::DFT<double>> dft = storm::api::loadDFTGalileoFile<double>(file);
EXPECT_TRUE(storm::api::isWellFormed(*dft));
@ -199,4 +211,11 @@ namespace {
double result = this->analyzeReliability(STORM_TEST_RESOURCES_DIR "/dft/hecs_2_2.dft", 1.0);
EXPECT_FLOAT_EQ(result, 0.00021997582);
}
TYPED_TEST(DftModelCheckerTest, SmtTest) {
storm::solver::SmtSolver::CheckResult result = this->analyzeSMT(STORM_TEST_RESOURCES_DIR "/dft/and.dft");
EXPECT_EQ(result, storm::solver::SmtSolver::CheckResult::Unsat);
result = this->analyzeSMT(STORM_TEST_RESOURCES_DIR "/dft/pand.dft");
EXPECT_EQ(result, storm::solver::SmtSolver::CheckResult::Sat);
}
}
Write Preview
Loading…
Cancel
Save