/// <summary>
/// This is a version of the join which causes a partial propagation of the information from Intervals to Symbolic upper bounds
/// </summary>
/// <param name="a">The other element</param>
public override IAbstractDomain Join(IAbstractDomain a)
{
if (this.IsBottom)
{
return(a);
}
if (a.IsBottom)
{
return(this);
}
if (this.IsTop)
{
return(this);
}
if (a.IsTop)
{
return(a);
}
//^ assert a is ReducedCartesianAbstractDomain<LeftDomain, RightDomain>;
Pentagons < Rational, Expression> r = a as Pentagons < Rational, Expression>;
if (a == null)
{
Debug.Assert(false, "Error cannot compare a cartesian abstract element with a " + a.GetType());
}
IntervalEnvironment < Rational, Expression> joinLeftPart;
WeakUpperBounds <Expression, Rational> joinRightPart;
{
// These two lines have a weak notion of closure, which essentially avoids dropping "x < y" if it is implied by the intervals abstract domain
// It seems that it is as precise as the expensive join
joinRightPart = this.Right.Join(r.Right, this.Left, r.Left);
joinLeftPart = (IntervalEnvironment < Rational, Expression>) this.Left.Join(r.Left);
}
return(this.Factory(joinLeftPart, joinRightPart));
}
/// <summary>
/// The pairwise widening
/// </summary>
public override IAbstractDomain Widening(IAbstractDomain prev)
{
if (this.IsBottom)
{
return(prev);
}
if (prev.IsBottom)
{
return(this);
}
Debug.Assert(prev is Pentagons < Rational, Expression>, "Wrong type of the domain for the widening...");
Pentagons < Rational, Expression> asIntWSUB = (Pentagons < Rational, Expression>)prev;
IntervalEnvironment < Rational, Expression> widenLeft = (IntervalEnvironment < Rational, Expression>) this.Left.Widening(asIntWSUB.Left);
WeakUpperBounds <Expression, Rational> widenRight = (WeakUpperBounds <Expression, Rational>) this.Right.Widening(asIntWSUB.Right);
Pentagons < Rational, Expression> result = (Pentagons < Rational, Expression>) this.Factory(widenLeft, widenRight);
return(result);
}
override public bool LessEqual(IAbstractDomain /*!*/ a)
{
if (this == a)
{
return(true);
}
if (this.IsBottom)
{
return(true);
}
if (this.IsTop)
{
return(a.IsTop);
}
if (a.IsBottom)
{
return(false);
}
if (a.IsTop)
{
return(true);
}
Pentagons < Rational, Expression> r = a as Pentagons < Rational, Expression>;
bool b1 = this.Left.LessEqual(r.Left);
if (!b1)
{
return(false);
}
bool b2 = this.Right.LessEqual(r.Right);
return(b2);
}
