private InstructionDependency[] Convert(InstructionDependency[] preds, TypeDescriptor from, TypeDescriptor to)
{
if (from.Equals(to))
{
// nothing to do
return preds;
}
else if (IsSFix(from) && IsUFix(to))
{
var fromFmt = SFix.GetFormat(from);
var toFmt = UFix.GetFormat(to);
int interIW = toFmt.IntWidth + 1;
int interFW = toFmt.FracWidth;
if (interIW != fromFmt.IntWidth ||
interFW != fromFmt.FracWidth)
{
var interType = SFix.MakeType(interIW, interFW);
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, interType));
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(1, interType, to));
}
else
{
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, to));
}
return new InstructionDependency[0];
}
else if (IsUFix(from) && IsSFix(to))
{
var fromFmt = UFix.GetFormat(from);
var toFmt = SFix.GetFormat(to);
int interIW = toFmt.IntWidth - 1;
int interFW = toFmt.FracWidth;
if (interIW != fromFmt.IntWidth ||
interFW != fromFmt.FracWidth)
{
var interType = UFix.MakeType(interIW, interFW);
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, interType));
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(1, interType, to));
}
else
{
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, to));
}
return new InstructionDependency[0];
}
else if (IsSLV(from))
{
int wfrom = TypeLowering.Instance.GetWireWidth(from);
int wto = TypeLowering.Instance.GetWireWidth(to);
if (wfrom == wto)
{
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, to));
}
else
{
var interType = StdLogicVector.MakeType(wto);
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, interType));
Convert(interType, to);
}
return new InstructionDependency[0];
}
else if (IsSLV(to))
{
int wfrom = TypeLowering.Instance.GetWireWidth(from);
int wto = TypeLowering.Instance.GetWireWidth(to);
if (wfrom == wto)
{
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, to));
}
else
{
var interType = StdLogicVector.MakeType(wfrom);
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, interType));
Convert(interType, to);
}
return new InstructionDependency[0];
}
else
{
Emit(DefaultInstructionSet.Instance.Convert().CreateStk(preds, 1, from, to));
return new InstructionDependency[0];
}
}
/// <summary>
/// Returns a type which is able to represent either of two given types without loss of precision
/// </summary>
/// <param name="td1">first given type</param>
/// <param name="td2">second given type</param>
/// <returns></returns>
private static TypeDescriptor GetCommonType(TypeDescriptor td1, TypeDescriptor td2)
{
if (td1.Equals(td2))
return td1;
if (IsSFix(td1) && IsUFix(td2))
{
var fmt1 = SFix.GetFormat(td1);
var fmt2 = UFix.GetFormat(td2);
return SFix.MakeType(
Math.Max(fmt1.IntWidth, fmt2.IntWidth + 1),
Math.Max(fmt1.FracWidth, fmt2.FracWidth));
}
else if (IsUFix(td1) && IsSFix(td2))
{
return GetCommonType(td2, td1);
}
else if (IsSFix(td1) && IsSFix(td2))
{
var fmt1 = SFix.GetFormat(td1);
var fmt2 = SFix.GetFormat(td2);
return SFix.MakeType(
Math.Max(fmt1.IntWidth, fmt2.IntWidth),
Math.Max(fmt1.FracWidth, fmt2.FracWidth));
}
else if (IsUFix(td1) && IsUFix(td2))
{
var fmt1 = UFix.GetFormat(td1);
var fmt2 = UFix.GetFormat(td2);
return UFix.MakeType(
Math.Max(fmt1.IntWidth, fmt2.IntWidth),
Math.Max(fmt1.FracWidth, fmt2.FracWidth));
}
else if (IsSigned(td1))
{
var fmt = SFix.GetFormat(td1);
var td1x = SFix.MakeType(fmt.IntWidth, fmt.FracWidth);
return GetCommonType(td1x, td2);
}
else if (IsSigned(td2))
{
return GetCommonType(td2, td1);
}
else if (IsUnsigned(td1))
{
var fmt = UFix.GetFormat(td1);
var td1x = UFix.MakeType(fmt.IntWidth, fmt.FracWidth);
return GetCommonType(td1x, td2);
}
else if (IsUnsigned(td2))
{
return GetCommonType(td2, td1);
}
else
{
throw new NotSupportedException(
"Cannot determine common type between " +
td1.ToString() + " and " + td2.ToString());
}
}
private string CheckStatic()
{
if (HasIntrinsicTypeOverride)
{
return(null);
}
if (CILType.IsArray)
{
TypeDescriptor tdref = GetElement0Type();
string innerCheck = tdref.CheckStatic();
if (innerCheck != null)
{
return(innerCheck);
}
if (_sample == null)
{
return("No sample - not able to determine whether type descriptor is static");
}
Array array = (Array)_sample;
int[] indices = new int[array.Rank];
do
{
object elem = array.GetValue(indices);
if (elem == null)
{
return("Null array element");
}
TypeDescriptor td = new TypeDescriptor(elem);
if (!tdref.Equals(td))
{
return("Different element types in array");
}
int dim;
for (dim = 0; dim < indices.Length; dim++)
{
++indices[dim];
if (indices[dim] < array.GetLength(dim))
{
break;
}
indices[dim] = 0;
}
if (dim == indices.Length)
{
break;
}
}while (true);
return(null);
}
else
{
if (!CILType.IsValueType && !CILType.IsPrimitive)
{
return("Type is neither primitive nor a value type");
}
TypeDescriptor[] deps = GetDependentTypes();
foreach (TypeDescriptor dep in deps)
{
string innerCheck = dep.CheckStatic();
if (innerCheck != null)
{
return(innerCheck);
}
}
return(null);
}
}
