/// <summary>
/// Retrieves the value of the expression
/// </summary>
/// <param name="evalContext">Evaluation context</param>
/// <param name="checkOnly"></param>
/// <returns>Evaluated expression value</returns>
public override ExpressionValue Evaluate(IExpressionEvaluationContext evalContext, bool checkOnly = false)
{
// --- Test for operand errors
var addrValue = StartAddress.Evaluate(evalContext);
if (addrValue.Type == ExpressionValueType.Error)
{
EvaluationError = StartAddress.EvaluationError;
return(ExpressionValue.Error);
}
var endValue = EndAddress == null ? new ExpressionValue(1) : EndAddress.Evaluate(evalContext);
if (endValue.Type == ExpressionValueType.Error)
{
EvaluationError = EndAddress?.EvaluationError;
return(ExpressionValue.Error);
}
if (checkOnly)
{
return(ExpressionValue.NonEvaluated);
}
if (addrValue.Type == ExpressionValueType.ByteArray || endValue.Type == ExpressionValueType.ByteArray)
{
EvaluationError = "Memory address operator cannot be applied on a byte array";
return(ExpressionValue.Error);
}
return(new ExpressionValue(evalContext.GetMachineContext().GetMemorySection(addrValue.AsWord(),
endValue.AsWord())));
}
/// <summary>
/// Retrieves the value of the expression
/// </summary>
/// <param name="evalContext">Evaluation context</param>
/// <param name="checkOnly"></param>
/// <returns>Evaluated expression value</returns>
public override ExpressionValue Evaluate(IExpressionEvaluationContext evalContext, bool checkOnly = false)
{
if (checkOnly)
{
return(ExpressionValue.NonEvaluated);
}
var regValue = evalContext.GetMachineContext().GetRegisterValue(RegisterName);
return(new ExpressionValue(regValue));
}
/// <summary> /// Evaluates a memory touch expression /// </summary> /// <param name="evalContext">Evaluation context</param> /// <param name="start">Start address (inclusive)</param> /// <param name="end">End address (inclusive)</param> /// <returns>True, if all bytes within the section has been touched</returns> public override byte[] EvalTouch(IExpressionEvaluationContext evalContext, ushort start, ushort end) => evalContext.GetMachineContext().GetMemoryWriteSection(start, end);
/// <summary> /// This property signs if an expression is ready to be evaluated, /// namely, all subexpression values are known /// </summary> /// <param name="evalContext">Evaluation context</param> /// <returns>True, if the expression is ready; otherwise, false</returns> public override bool ReadyToEvaluate(IExpressionEvaluationContext evalContext) => evalContext.GetMachineContext() != null;
/// <summary> /// This property signs if an expression is ready to be evaluated, /// namely, all subexpression values are known /// </summary> /// <param name="evalContext">Evaluation context</param> /// <returns>True, if the expression is ready; otherwise, false</returns> public override bool ReadyToEvaluate(IExpressionEvaluationContext evalContext) => StartAddress.ReadyToEvaluate(evalContext) && (EndAddress == null || EndAddress.ReadyToEvaluate(evalContext)) && evalContext.GetMachineContext() != null;
