/// <summary>
/// Pops the value on the stack, converts it from one type to another, then pushes the
/// result onto the stack.
/// </summary>
/// <param name="il"> The IL generator. </param>
/// <param name="fromType"> The type to convert from. </param>
/// <param name="toType"> The type to convert to. </param>
private static void EmitTypeConversion(ILGenerator il, Type fromType, Type toType)
{
// If the source type equals the destination type, then there is nothing to do.
if (fromType == toType)
{
return;
}
// Emit for each type of argument we support.
if (toType == typeof(int))
{
EmitConversion.ToInteger(il, PrimitiveTypeUtilities.ToPrimitiveType(fromType));
}
else if (typeof(ObjectInstance).IsAssignableFrom(toType))
{
EmitConversion.Convert(il, PrimitiveTypeUtilities.ToPrimitiveType(fromType), PrimitiveType.Object);
if (toType != typeof(ObjectInstance))
{
// Convert to null if the from type isn't compatible with the to type.
// For example, if the target type is FunctionInstance and the from type is ArrayInstance, then pass null.
il.IsInstance(toType);
}
}
else
{
EmitConversion.Convert(il, PrimitiveTypeUtilities.ToPrimitiveType(fromType), PrimitiveTypeUtilities.ToPrimitiveType(toType));
}
}