de.uka.ilkd.key.rule.join.procedures

Class JoinIfThenElseAntecedent

java.lang.Object

de.uka.ilkd.key.rule.join.JoinProcedure

de.uka.ilkd.key.rule.join.procedures.JoinIfThenElseAntecedent

public class JoinIfThenElseAntecedent
extends JoinProcedure

Rule that joins two sequents based on the if-then-else construction: If two locations are assigned different values in the states, the value in the joined state is chosen based on the path condition. This rule retains total precision. In contrast to the JoinIfThenElse rule, the distinction is not realized in the update / symbolic state, but in the antecedent / path condition. This can be much more efficient.

Author:

Dominic Scheurer

See Also:

JoinIfThenElse, JoinRule

Field Summary

Fields

Modifier and Type	Field and Description
private static String	DISPLAY_NAME
private static JoinIfThenElseAntecedent	INSTANCE

Constructor Summary

Constructors

Constructor and Description
JoinIfThenElseAntecedent()

Method Summary

Modifier and Type	Method and Description
private static ImmutableSet<Term>	getIfThenElseConstraints(Term constrained, Term ifTerm, Term elseTerm, SymbolicExecutionState state1, SymbolicExecutionState state2, Term distinguishingFormula, Services services) Returns a list of if-then-else constraints for the given constrained term, states and if/else terms.
static JoinIfThenElseAntecedent	instance()
Triple<ImmutableSet<Term>,Term,ImmutableSet<Name>>	joinValuesInStates(Term v, SymbolicExecutionState state1, Term valueInState1, SymbolicExecutionState state2, Term valueInState2, Term distinguishingFormula, Services services) Joins two values valueInState1 and valueInState2 of corresponding SE states state1 and state2 to a new value of a join state.
boolean	requiresDistinguishablePathConditions()
String	toString()

Methods inherited from class de.uka.ilkd.key.rule.join.JoinProcedure

getJoinProcedures, getProcedureByName

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

INSTANCE

private static JoinIfThenElseAntecedent INSTANCE

DISPLAY_NAME

private static final String DISPLAY_NAME

See Also:

Constant Field Values

Constructor Detail

JoinIfThenElseAntecedent

public JoinIfThenElseAntecedent()

Method Detail

instance

public static JoinIfThenElseAntecedent instance()

joinValuesInStates

public Triple<ImmutableSet<Term>,Term,ImmutableSet<Name>> joinValuesInStates(Term v,
                                                                             SymbolicExecutionState state1,
                                                                             Term valueInState1,
                                                                             SymbolicExecutionState state2,
                                                                             Term valueInState2,
                                                                             Term distinguishingFormula,
                                                                             Services services)

Description copied from class: JoinProcedure

Joins two values valueInState1 and valueInState2 of corresponding SE states state1 and state2 to a new value of a join state.

Specified by:

joinValuesInStates in class JoinProcedure

Parameters:

v - The variable for which the values should be joined

state1 - First SE state.

valueInState1 - Value in state1.

state2 - Second SE state.

valueInState2 - Value in state2.

distinguishingFormula - The user-specified distinguishing formula. May be null (for automatic generation).

services - The services object.

Returns:

A joined value for valueInState1 and valueInState2, that is a triple consisting of new constraints, the actual value and new names introduced.

requiresDistinguishablePathConditions

public boolean requiresDistinguishablePathConditions()

Specified by:

requiresDistinguishablePathConditions in class JoinProcedure

Returns:

true iff the join procedure requires distinguishable path conditions. This is usually the case for procedures working with concrete values of input states, and can be false for abstraction methods.

getIfThenElseConstraints

private static ImmutableSet<Term> getIfThenElseConstraints(Term constrained,
                                                           Term ifTerm,
                                                           Term elseTerm,
                                                           SymbolicExecutionState state1,
                                                           SymbolicExecutionState state2,
                                                           Term distinguishingFormula,
                                                           Services services)

Returns a list of if-then-else constraints for the given constrained term, states and if/else terms.

Parameters:

constrained - The constrained term.

ifTerm - The value for the if case.

elseTerm - The value for the else case.

state1 - First SE state ("if").

state2 - Second SE state ("else").

distinguishingFormula - The user-specified distinguishing formula. May be null (for automatic generation).

services - The services object.

Returns:

A list of if-then-else constraints for the given constrained term, states and if/else terms.

toString

public String toString()

Overrides:

toString in class Object