public static InstructionNode UncodifyInstructionFormat(
int number,
Var var)
{
if (number < 0)
{
throw new InvalidOperationException();
}
InstructionNode fakeInstruction;
if (number == 0)
{
fakeInstruction = new UnaryExpressionInstructionNode(
var.ToString(),
-1);
}
else if (number == 1 || number == 2)
{
fakeInstruction = new BinaryExpressionInstructionNode(
var.ToString(),
number == 1 ? "+" : "-");
}
else
{
var codifiedLabel = number - 2;
var label = UncodifyLabel(codifiedLabel);
fakeInstruction = new ConditionalInstructionNode(
var.ToString(),
label.ToString(),
-1);
}
return(fakeInstruction);
}
private static int StepConditional(
ConditionalInstructionNode conditional,
int instructionPointer,
IEnumerable <InstructionNode> instructions)
{
int newInstructionPointer;
var targetVar = GetTargetVar(conditional.Var.Type);
int index = GetNormalizedIndex(conditional);
if (targetVar[index] != 0)
{
var goToInstruction = instructions.FirstOrDefault(item => item.Label == conditional.TargetLabel);
if (goToInstruction != null)
{
// TODO avoid array conversion
newInstructionPointer = Array.IndexOf(instructions.ToArray(), goToInstruction);
}
else
{
// We suppose it's the exit label
newInstructionPointer = instructions.Count();
}
}
else
{
newInstructionPointer = instructionPointer + 1;
}
return(newInstructionPointer);
}
public void Instruction2()
{
var instruction = new ConditionalInstructionNode("Y", "A", 0)
{
Label = new Label("A")
};
AssertEqualCodified(instruction, 29);
}
public void ConditionalInstructionFormat()
{
const string rawLabel = "A";
var instruction = new ConditionalInstructionNode("X", rawLabel, 0);
var label = new Label(rawLabel);
var codifiedLabel = Codifier.Codify(label);
AssertEqualCodifiedFormat(instruction, codifiedLabel + 2);
}
public void Instruction3()
{
var instruction = new ConditionalInstructionNode("X", "A", 0);
AssertEqualCodified(instruction, 46);
}
