/// <summary>
/// Returns a valueset whose values are the truncation of this valueset's
/// values.
/// </summary>
/// <param name="dt"></param>
/// <returns></returns>
public override ValueSet Truncate(DataType dt)
{
if (SI.Stride < 0)
{
return(this);
}
var mask = (1 << dt.BitSize) - 1;
StridedInterval siNew;
if (SI.Low == SI.High)
{
siNew = StridedInterval.Constant(
Constant.Create(dt, SI.Low & mask));
}
else
{
siNew = StridedInterval.Create(
SI.Stride, 0, Math.Min(mask, SI.High));
}
return(new IntervalValueSet(dt, siNew));
}
public ValueSet VisitBinaryExpression(BinaryExpression binExp)
{
var cLeft = binExp.Left as Constant;
var cRight = binExp.Right as Constant;
//$TODO: it would be great if Address were simply a Constant.
// but we have segmented addresses which need special treatment
// everywhere.
if (binExp.Left is Address aLeft)
{
cLeft = aLeft.ToConstant();
}
if (binExp.Right is Address aRight)
{
cRight = aRight.ToConstant();
}
if (cLeft != null && cRight != null)
{
return(new IntervalValueSet(
cLeft.DataType,
StridedInterval.Constant(
binExp.Operator.ApplyConstants(cLeft, cRight))));
}
if (cLeft == null && cRight != null)
{
var left = binExp.Left.Accept(this);
if (binExp.Operator == Operator.IAdd)
{
return(left.Add(cRight));
}
else if (binExp.Operator == Operator.And)
{
return(left.And(cRight));
}
else if (binExp.Operator == Operator.Shl)
{
return(left.Shl(cRight));
}
else if (binExp.Operator == Operator.IMul)
{
return(left.IMul(cRight));
}
else if (binExp.Operator == Operator.ISub)
{
return(left.Sub(cRight));
}
}
if (cRight == null && cLeft != null)
{
var right = binExp.Right.Accept(this);
if (binExp.Operator == Operator.IAdd)
{
return(right.Add(cLeft));
}
else if (binExp.Operator == Operator.And)
{
return(right.And(cLeft));
}
}
if (binExp.Operator == Operator.IAdd)
{
if (cmp.Equals(binExp.Left, binExp.Right))
{
var left = binExp.Left.Accept(this);
return(left.Shl(Constant.Int32(1)));
}
}
return(IntervalValueSet.Any);
}
