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

Prism next state generator now deals with unbounded integer variables.

tempestpy_adaptions
Tim Quatmann 4 years ago
parent
1fe0254f5d
commit
bdd89d87b2
No known key found for this signature in database GPG Key ID: 6EDE19592731EEC3
4 changed files with 81 additions and 43 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. 2
      src/storm/generator/PrismNextStateGenerator.cpp
  2. 106
      src/storm/generator/VariableInformation.cpp
  3. 2
      src/storm/generator/VariableInformation.h
  4. 12
      src/test/storm/builder/ExplicitPrismModelBuilderTest.cpp

2
src/storm/generator/PrismNextStateGenerator.cpp
View File

@ -33,7 +33,7 @@ namespace storm {
// Only after checking validity of the program, we initialize the variable information.
this->checkValid();
this->variableInformation = VariableInformation(program, options.isAddOutOfBoundsStateSet());
this->variableInformation = VariableInformation(program, options.getReservedBitsForUnboundedVariables(), options.isAddOutOfBoundsStateSet());
// Create a proper evalator.
this->evaluator = std::make_unique<storm::expressions::ExpressionEvaluator<ValueType>>(program.getManager());

106
src/storm/generator/VariableInformation.cpp
View File

@ -34,7 +34,47 @@ namespace storm {
// Intentionally left empty.
}
VariableInformation::VariableInformation(storm::prism::Program const& program, bool outOfBoundsState) : totalBitOffset(0) {
/*!
* Small helper function that sets unspecified lower/upper bounds for an integer variable based on the provided reservedBitsForUnboundedVariables and returns the number of bits required to represent the final variable range
* @pre If has[Lower,Upper]Bound is true, [lower,upper]Bound must be set to the corresponding bound.
* @post lowerBound and upperBound are set to the considered bound for this variable
* @param hasLowerBound shall be true iff there is a lower bound given
* @param lowerBound a reference to the lower bound value
* @param hasUpperBound shall be true iff there is an upper bound given
* @param upperBound a reference to the upper bound
* @param reservedBitsForUnboundedVariables the number of bits that shall be used to represent unbounded variables
* @return the number of bits required to represent the final variable range
*/
uint64_t getBitWidthLowerUpperBound(bool const& hasLowerBound, int64_t& lowerBound, bool const& hasUpperBound, int64_t& upperBound, uint64_t const& reservedBitsForUnboundedVariables) {
if (hasLowerBound) {
if (hasUpperBound) {
STORM_LOG_THROW(lowerBound <= upperBound, storm::exceptions::WrongFormatException, "Lower bound must not be above upper bound");
// We do not have to set any bounds in this case.
// Return the number of bits required to store all the values between lower and upper bound
return static_cast<uint64_t>(std::ceil(std::log2(upperBound - lowerBound + 1)));
} else {
// We only have a lower bound. Find the largest upper bound we can store with the given number of bits.
upperBound = lowerBound + ((1ll << reservedBitsForUnboundedVariables) - 1);
}
} else {
if (hasUpperBound) {
// We only have an upper bound. Find the smallest lower bound we can store with the given number of bits
lowerBound = upperBound - ((1ll << reservedBitsForUnboundedVariables) - 1);
} else {
// We neither have a lower nor an upper bound. Take the usual n-bit integer values for lower/upper bounds
lowerBound = -(1ll << (reservedBitsForUnboundedVariables - 1)); // = -2^(reservedBits-1)
upperBound = (1ll << (reservedBitsForUnboundedVariables - 1)) - 1; // = 2^(reservedBits-1) - 1
}
}
// If we reach this point, it means that the variable is unbounded.
// Lets check for potential overflows.
STORM_LOG_THROW(lowerBound <= upperBound, storm::exceptions::WrongFormatException, "Lower bound must not be above upper bound. Has there been an integer over-/underflow?");
// By choice of the lower/upper bound, the number of reserved bits must coincide with the bitwidth
STORM_LOG_ASSERT(reservedBitsForUnboundedVariables == static_cast<uint64_t>(std::ceil(std::log2(upperBound - lowerBound + 1))), "Unexpected bitwidth for unbounded variable.");
return reservedBitsForUnboundedVariables;
}
VariableInformation::VariableInformation(storm::prism::Program const& program, uint64_t reservedBitsForUnboundedVariables, bool outOfBoundsState) : totalBitOffset(0) {
if (outOfBoundsState) {
outOfBoundsBit = 0;
++totalBitOffset;
@ -47,11 +87,15 @@ namespace storm {
++totalBitOffset;
}
for (auto const& integerVariable : program.getGlobalIntegerVariables()) {
int_fast64_t lowerBound = integerVariable.getLowerBoundExpression().evaluateAsInt();
int_fast64_t upperBound = integerVariable.getUpperBoundExpression().evaluateAsInt();
STORM_LOG_THROW(lowerBound <= upperBound, storm::exceptions::WrongFormatException, "Lower bound must not be above upper bound");
uint_fast64_t bitwidth = static_cast<uint_fast64_t>(std::ceil(std::log2(upperBound - lowerBound + 1)));
integerVariables.emplace_back(integerVariable.getExpressionVariable(), lowerBound, upperBound, totalBitOffset, bitwidth, true, integerVariable.isObservable());
int64_t lowerBound, upperBound;
if (integerVariable.hasLowerBoundExpression()) {
lowerBound = integerVariable.getLowerBoundExpression().evaluateAsInt();
}
if (integerVariable.hasUpperBoundExpression()) {
upperBound = integerVariable.getUpperBoundExpression().evaluateAsInt();
}
uint64_t bitwidth = getBitWidthLowerUpperBound(integerVariable.hasLowerBoundExpression(), lowerBound, integerVariable.hasUpperBoundExpression(), upperBound, reservedBitsForUnboundedVariables);
integerVariables.emplace_back(integerVariable.getExpressionVariable(), lowerBound, upperBound, totalBitOffset, bitwidth, true, integerVariable.isObservable(), !integerVariable.hasLowerBoundExpression() || !integerVariable.hasUpperBoundExpression());
totalBitOffset += bitwidth;
}
for (auto const& module : program.getModules()) {
@ -60,11 +104,15 @@ namespace storm {
++totalBitOffset;
}
for (auto const& integerVariable : module.getIntegerVariables()) {
int_fast64_t lowerBound = integerVariable.getLowerBoundExpression().evaluateAsInt();
int_fast64_t upperBound = integerVariable.getUpperBoundExpression().evaluateAsInt();
STORM_LOG_THROW(lowerBound <= upperBound, storm::exceptions::WrongFormatException, "Lower bound must not be above upper bound");
uint_fast64_t bitwidth = static_cast<uint_fast64_t>(std::ceil(std::log2(upperBound - lowerBound + 1)));
integerVariables.emplace_back(integerVariable.getExpressionVariable(), lowerBound, upperBound, totalBitOffset, bitwidth, false, integerVariable.isObservable());
int64_t lowerBound, upperBound;
if (integerVariable.hasLowerBoundExpression()) {
lowerBound = integerVariable.getLowerBoundExpression().evaluateAsInt();
}
if (integerVariable.hasUpperBoundExpression()) {
upperBound = integerVariable.getUpperBoundExpression().evaluateAsInt();
}
uint64_t bitwidth = getBitWidthLowerUpperBound(integerVariable.hasLowerBoundExpression(), lowerBound, integerVariable.hasUpperBoundExpression(), upperBound, reservedBitsForUnboundedVariables);
integerVariables.emplace_back(integerVariable.getExpressionVariable(), lowerBound, upperBound, totalBitOffset, bitwidth, false, integerVariable.isObservable(), !integerVariable.hasLowerBoundExpression() || !integerVariable.hasUpperBoundExpression());
totalBitOffset += bitwidth;
}
}
@ -81,22 +129,6 @@ namespace storm {
for (auto const& automaton : model.getAutomata()) {
STORM_LOG_THROW(!automaton.getVariables().containsNonTransientRealVariables(), storm::exceptions::InvalidArgumentException, "Cannot build model from JANI model that contains non-transient real variables in automaton '" << automaton.getName() << "'.");
}
//
// for (auto const& variable : model.getGlobalVariables().getBooleanVariables()) {
// if (!variable.isTransient()) {
// booleanVariables.emplace_back(variable.getExpressionVariable(), totalBitOffset, true, true);
// ++totalBitOffset;
// }
// }
// for (auto const& variable : model.getGlobalVariables().getBoundedIntegerVariables()) {
// if (!variable.isTransient()) {
// int_fast64_t lowerBound = variable.getLowerBound().evaluateAsInt();
// int_fast64_t upperBound = variable.getUpperBound().evaluateAsInt();
// uint_fast64_t bitwidth = static_cast<uint_fast64_t>(std::ceil(std::log2(upperBound - lowerBound + 1)));
// integerVariables.emplace_back(variable.getExpressionVariable(), lowerBound, upperBound, totalBitOffset, bitwidth, true, true);
// totalBitOffset += bitwidth;
// }
// }
if (outOfBoundsState) {
outOfBoundsBit = 0;
@ -181,30 +213,24 @@ namespace storm {
}
for (auto const& variable : variableSet.getBoundedIntegerVariables()) {
if (!variable.isTransient()) {
int64_t lowerBound;
int64_t upperBound;
int64_t lowerBound, upperBound;
STORM_LOG_ASSERT(variable.hasLowerBound() || variable.hasUpperBound(), "Bounded integer variable has neither a lower nor an upper bound.");
if (variable.hasLowerBound()) {
lowerBound = variable.getLowerBound().evaluateAsInt();
if (variable.hasUpperBound()) {
upperBound = variable.getUpperBound().evaluateAsInt();
} else {
upperBound = lowerBound + ((1ll << reservedBitsForUnboundedVariables) - 1);
}
} else {
STORM_LOG_THROW(variable.hasUpperBound(), storm::exceptions::WrongFormatException, "Bounded integer variable has neither a lower nor an upper bound.");
if (variable.hasUpperBound()) {
upperBound = variable.getUpperBound().evaluateAsInt();
lowerBound = upperBound - ((1ll << reservedBitsForUnboundedVariables) - 1);
}
uint_fast64_t bitwidth = static_cast<uint_fast64_t>(std::ceil(std::log2(upperBound - lowerBound + 1)));
uint64_t bitwidth = getBitWidthLowerUpperBound(variable.hasLowerBound(), lowerBound, variable.hasUpperBound(), upperBound, reservedBitsForUnboundedVariables);
integerVariables.emplace_back(variable.getExpressionVariable(), lowerBound, upperBound, totalBitOffset, bitwidth, global, true, !variable.hasLowerBound() || !variable.hasUpperBound());
totalBitOffset += bitwidth;
}
}
for (auto const& variable : variableSet.getUnboundedIntegerVariables()) {
if (!variable.isTransient()) {
int64_t lowerBound = -(1ll << (reservedBitsForUnboundedVariables - 1));
int64_t upperBound = (1ll << (reservedBitsForUnboundedVariables - 1)) - 1;
integerVariables.emplace_back(variable.getExpressionVariable(), lowerBound, upperBound, totalBitOffset, reservedBitsForUnboundedVariables, global, true, true);
int64_t lowerBound, upperBound;
uint64_t bitwidth = getBitWidthLowerUpperBound(false, lowerBound, false, upperBound, reservedBitsForUnboundedVariables);
integerVariables.emplace_back(variable.getExpressionVariable(), lowerBound, upperBound, totalBitOffset, bitwidth, global, true, true);
totalBitOffset += reservedBitsForUnboundedVariables;
}
}

2
src/storm/generator/VariableInformation.h
View File

@ -98,7 +98,7 @@ namespace storm {
// A structure storing information about the used variables of the program.
struct VariableInformation {
VariableInformation(storm::prism::Program const& program, bool outOfBoundsState = false);
VariableInformation(storm::prism::Program const& program, uint64_t reservedBitsForUnboundedVariables, bool outOfBoundsState = false);
VariableInformation(storm::jani::Model const& model, std::vector<std::reference_wrapper<storm::jani::Automaton const>> const& parallelAutomata, uint64_t reservedBitsForUnboundedVariables, bool outOfBoundsState);
VariableInformation() = default;

12
src/test/storm/builder/ExplicitPrismModelBuilderTest.cpp
View File

@ -94,6 +94,12 @@ TEST(ExplicitPrismModelBuilderTest, Mdp) {
model = storm::builder::ExplicitModelBuilder<double>(program).build();
EXPECT_EQ(37ul, model->getNumberOfStates());
EXPECT_EQ(59ul, model->getNumberOfTransitions());
storm::storage::SymbolicModelDescription modelDescription = storm::parser::PrismParser::parse(STORM_TEST_RESOURCES_DIR "/mdp/unbounded.nm");
program = modelDescription.preprocess("N=-7").asPrismProgram();
model = storm::builder::ExplicitModelBuilder<double>(program).build();
EXPECT_EQ(9ul, model->getNumberOfStates());
EXPECT_EQ(9ul, model->getNumberOfTransitions());
}
TEST(ExplicitPrismModelBuilderTest, Ma) {
@ -125,3 +131,9 @@ TEST(ExplicitPrismModelBuilderTest, FailComposition) {
STORM_SILENT_ASSERT_THROW(storm::builder::ExplicitModelBuilder<double>(program).build(), storm::exceptions::WrongFormatException);
}
TEST(ExplicitPrismModelBuilderTest, FailUnbounded) {
storm::storage::SymbolicModelDescription modelDescription = storm::parser::PrismParser::parse(STORM_TEST_RESOURCES_DIR "/mdp/unbounded.nm");
storm::prism::Program program = modelDescription.preprocess("N=7").asPrismProgram();
STORM_SILENT_ASSERT_THROW(storm::builder::ExplicitModelBuilder<double>(program).build(), storm::exceptions::WrongFormatException);
}
Write Preview
Loading…
Cancel
Save