public override WExpr InterpretModel(Context context, Model model, ProgramBuilder builder)
{
int opChoice = GetConcChoice(context, model);
WCComparison.CompareType op = (opChoice == 0) ? WCComparison.CompareType.eq : WCComparison.CompareType.neq;
WExpr rv = new WCComparison((WEVar)x.InterpretModel(context, model, builder), op, new WEConst(0));
builder.CheckExpr(rv);
return(rv);
}
public override WExpr InterpretModel(Context context, Model model, ProgramBuilder builder)
{
WEVar arg1Conc = (WEVar)arg1.InterpretModel(context, model, builder);
WCComparison.CompareType comp = (WCComparison.CompareType) this.GetConcChoice(context, model);
WEOperand arg2Conc = (WEOperand)arg2.InterpretModel(context, model, builder);
WExpr rv = new WCComparison(arg1Conc, comp, arg2Conc);
builder.CheckExpr(rv);
return(rv);
}
public override bool KeepProgram(WExpr expr)
{
#region filter out: x_i = x_i
if (expr is WEArith)
{
WEArith e = (WEArith)expr;
if (e.op == WEArith.ArithOp.plus || e.op == WEArith.ArithOp.minus)
{
if (e.arg1 is WEVar && e.arg2 is WEConst)
{
if (e.lhs.id == ((WEVar)e.arg1).id && ((WEConst)e.arg2).value == 0)
{
return(false);
}
}
if (e.arg2 is WEVar && e.arg1 is WEConst)
{
if (e.lhs.id == ((WEVar)e.arg2).id && ((WEConst)e.arg1).value == 0)
{
return(false);
}
}
}
}
#endregion
#region filter out: x = x_i - x_i
if (expr is WEArith)
{
WEArith e = (WEArith)expr;
if (e.op == WEArith.ArithOp.minus)
{
if (e.arg1 is WEVar && e.arg2 is WEVar)
{
if (((WEVar)e.arg1).id == ((WEVar)e.arg2).id)
{
return(false);
}
}
}
}
#endregion
#region filter out: unsatisfiable and tautological comparisons
if (expr is WCComparison)
{
WCComparison e = (WCComparison)expr;
if (e.arg2 is WEVar)
{
if (e.arg1.id == ((WEVar)e.arg2).id)
{
return(false);
}
}
else
{
if (e.arg2.IsZero() && e.op == WCComparison.CompareType.l)
{
return(false);
}
}
}
#endregion
#region filter out: if statements where the <then> and <else> parts are the same
if (expr is WEIf)
{
WEIf e = (WEIf)expr;
if (e.elseBody != null)
{
if (e.thenBody.ToString() == e.elseBody.ToString())
{
return(false);
}
}
}
#endregion
#region filter out: compound conditions of the form C_i op C_i
if (expr is WCCompound)
{
WCCompound e = (WCCompound)expr;
if (e.cond1.ToString() == e.cond2.ToString())
{
return(false);
}
}
#endregion
return(true);
}
