public bool TryInlineCode(Decision decision)
{
int index = knownDecisions.IndexOf(decision);
if (index < 0)
{
knownDecisions.Insert(generationIndex++, decision);
decision.Accept(visitor);
return true;
}
else if (index >= generationIndex)
{
if (index != generationIndex)
{
// Swap next planned element and just generated element
knownDecisions[index] = knownDecisions[generationIndex];
knownDecisions[generationIndex] = decision;
}
++generationIndex;
decision.Accept(visitor);
return true;
}
return false;
}
public void PlanCode(Decision decision)
{
if (!knownDecisions.Contains(decision))
{
knownDecisions.Add(decision);
}
}
private Ref<Labels> GetNodeLabel(Decision decision)
{
if (!decision.Label.HasValue)
{
decision.Label = labels.Count;
labels.Add(emit.Labels.Generate().GetRef());
strategy.PlanCode(decision);
}
return labels[decision.Label.Value];
}
private void GenerateCodeOrJump(Decision decision)
{
if (!strategy.TryInlineCode(decision))
{
emit.Br(GetNodeLabel(decision));
}
}
private int Eval(Decision node, int input)
{
return node.Decide(input);
}
private void PrintProgram(Decision nodes, Decision defaultDecision = null)
{
if (defaultDecision == null)
{
defaultDecision = new ActionDecision(-1);
}
StringBuilder output = new StringBuilder();
var writer = new DecisionProgramWriter(output);
writer.Build(nodes, defaultDecision);
Debug.WriteLine(output);
}
private string GetLabelText(Decision node)
{
return(FormatLabel(GetLabel(node)));
}
private void PutLabel(Decision labelNode)
{
output.Append(GetLabelText(labelNode)).Append(": ");
}
public void Build(Decision root, Decision defaultDecision)
{
this.defaultDecision = defaultDecision;
strategy.PlanCode(root);
strategy.GenerateCode();
}
private int GetLabel(Decision decision)
{
if (decision.Label.HasValue)
{
return decision.Label.Value;
}
strategy.PlanCode(decision);
decision.Label = labelGen++;
return decision.Label.Value;
}
private void GenerateCodeOrJump(Decision decision)
{
if (!strategy.TryInlineCode(decision))
{
output.Append("goto ").Append(GetLabelText(decision)).AppendLine();
}
}
public void Build(Decision root, Decision defaultDecision)
{
this.defaultDecision = defaultDecision;
strategy.PlanCode(root);
strategy.GenerateCode();
}
private void PutLabel(Decision labelNode)
{
output.Append(GetLabelText(labelNode)).Append(": ");
}
private string GetLabelText(Decision node)
{
return FormatLabel(GetLabel(node));
}
private Decision Build(
int first,
int last,
KeyValuePair <int, int>[] upperBounds)
{
int size = last - first;
if (size > platform.MaxLinearCount)
{
// binary search nodes
int middle = first + (size - 1) / 2;
var branch = new RelationalBranchDecision(
RelationalOperator.LessOrEqual,
upperBounds[middle].Key);
// positive branch
branch.Left = Build(first, middle + 1, upperBounds);
// negative branch
branch.Right = Build(middle + 1, last, upperBounds);
return(branch);
}
else
{
Decision result = null;
RelationalBranchDecision lastBranch = null;
// linear search nodes
for (; first != last; ++first)
{
int key = upperBounds[first].Key;
RelationalBranchDecision branch;
if (first > 0 && (key - upperBounds[first - 1].Key) == 1)
{
branch = new RelationalBranchDecision(RelationalOperator.Equal, key);
}
else
{
branch = new RelationalBranchDecision(RelationalOperator.LessOrEqual, key);
}
branch.Left = new ActionDecision(upperBounds[first].Value);
branch.Right = null;
if (lastBranch != null)
{
lastBranch.Right = branch;
}
else
{
result = branch;
}
lastBranch = branch;
}
if (lastBranch != null)
{
lastBranch.Right = new ActionDecision(defaultAction);
}
else
{
result = new ActionDecision(defaultAction);
}
return(result);
}
}
private bool TryBuildElementaryTree(IIntMap<int> map, out Decision result)
{
result = null;
int count = 0;
foreach (var arrow in map.Enumerate())
{
if (arrow.Value == map.DefaultValue)
{
continue;
}
++count;
if (count > platform.MaxLinearCount || arrow.Key.LongSize != 1)
{
return false;
}
}
RelationalBranchDecision lastParent = null;
foreach (var arrow in map.Enumerate())
{
if (arrow.Value == map.DefaultValue)
{
continue;
}
var node = new RelationalBranchDecision(RelationalOperator.Equal, arrow.Key.First);
node.Left = GetActionDecision(arrow.Value);
if (lastParent == null)
{
result = node;
}
else
{
lastParent.Right = node;
}
lastParent = node;
}
lastParent.Right = DefaultActionDecision;
return true;
}