private void PrepareMainBlock()
{
RootBlock = new SimanticsBlock()
{
BlockType = SimanticsBlockType.BlockSequence,
//IBody = Instructions.Values.ToList()
};
}
private void ResetBlock(SimanticsBlock block)
{
block.VisitCount = 0;
foreach (var sblock in block.Body)
{
ResetBlock(sblock);
}
}
private void IdentifySequences()
{
//O(n) scan through instructions
//keep track of a "start" instruction, initially the first instruction.
//and build a list of instructions following it.
//whenever the new instruction has more than one input (or yields), complete the sequence (minus new) and start a new one on this instruction
//whenever the new instruction has more than one output, complete the sequence (including new) and start on the following
var firstSequence = new SimanticsBlock()
{
BlockType = SimanticsBlockType.InstructionSequence,
Parent = RootBlock,
StartInstructionIndex = 0,
};
var toProcess = new Queue <Tuple <byte, SimanticsBlock> >();
toProcess.Enqueue(new Tuple <byte, SimanticsBlock>(0, firstSequence));
Instructions[0].VisitCount = 1;
while (toProcess.Count > 0)
{
var process = toProcess.Dequeue();
var inst = Instructions[process.Item1];
var currentSequence = process.Item2;
if (currentSequence != null && (inst.From.Count > 1 || inst.Yields))
{
//something jumps back in here, likely a loop or yield.
if (currentSequence.IBody.Count > 0)
{
RootBlock.Body.Add(currentSequence);
currentSequence.LastInstructionIndex = currentSequence.IBody.Last().Index;
currentSequence = null;
/*
* currentSequence = new SimanticsBlock()
* {
* BlockType = SimanticsBlockType.InstructionSequence,
* Parent = RootBlock,
* StartInstructionIndex = inst.Index,
* };
*/
}
}
if (currentSequence == null)
{
currentSequence = new SimanticsBlock()
{
BlockType = SimanticsBlockType.InstructionSequence,
Parent = RootBlock,
StartInstructionIndex = inst.Index,
};
}
currentSequence.IBody.Add(inst);
var nextSequence = currentSequence;
if (inst.To.Count > 1 || inst.ReturnType == PrimitiveReturnType.SimanticsSubroutine)
{
RootBlock.Body.Add(currentSequence);
currentSequence.LastInstructionIndex = currentSequence.IBody.Last().Index;
nextSequence = null;
}
var hadDest = false;
foreach (var dest in inst.To)
{
if (dest != null && dest.VisitCount == 0)
{
toProcess.Enqueue(new Tuple <byte, SimanticsBlock>(dest.Index, nextSequence));
dest.VisitCount++;
hadDest = true;
}
}
if (!hadDest && nextSequence != null)
{
RootBlock.Body.Add(currentSequence);
currentSequence.LastInstructionIndex = currentSequence.IBody.Last().Index;
}
}
foreach (var sequence in RootBlock.Body)
{
var firstInst = sequence.IBody.First();
var lastInst = sequence.IBody.Last();
sequence.FromBlocks = RootBlock.Body.Where(x => firstInst.From.Contains(x.IBody.Last())).ToList();
sequence.NextBlocks = lastInst.To.Select(x => (x == null) ? null : RootBlock.Body.First(y => y.StartInstructionIndex == x.Index)).ToList();
}
}
