public override void Lower(InstructionBuilder builder)
{
var table = new JumpTableBuilder()
{
Depth = Depth,
};
var index = builder.AddJumpTable(table);
builder.AddInstruction(new Instruction()
{
Code = InstructionCode.Branch, Payload = index
});
builder.BeginBlock();
for (var i = 0; i < Children.Count; i++)
{
table.AddEntry(Literals[i], builder.Next);
Children[i].Lower(builder);
builder.AddInstruction(new Instruction()
{
Code = InstructionCode.Pop,
});
}
builder.EndBlock();
table.Exit = builder.Next;
}
private static int AddNode(Node node, List <State> states, List <JumpTableBuilder> tables)
{
Sort(node.Matches);
var index = states.Count;
states.Add(new State()
{
Matches = node.Matches.Select(CreateCandidate).ToArray(),
IsAccepting = node.Matches.Count > 0,
});
var table = new JumpTableBuilder()
{
Depth = node.Depth,
};
tables.Add(table);
foreach (var kvp in node.Literals)
{
if (kvp.Key == "*")
{
continue;
}
var transition = AddNode(kvp.Value, states, tables);
table.AddEntry(kvp.Key, transition);
}
var exitIndex = -1;
if (node.Literals.TryGetValue("*", out var exit))
{
exitIndex = AddNode(exit, states, tables);
}
table.Exit = exitIndex;
return(index);
}
public int AddJumpTable(JumpTableBuilder table)
{
_tables.Add(table);
return(_tables.Count - 1);
}