public RegionGraphBuilder(Procedure proc)
{
this.proc = proc;
this.btor = new Dictionary <Block, Region>();
this.graph = new DiGraph <Region>();
this.regionFactory = new RegionFactory();
this.switchPads = new Dictionary <Block, Dictionary <Block, Region> >();
}
/// <summary>
/// Builds a graph of regions based on the basic blocks of the code.
/// </summary>
/// <param name="proc"></param>
/// <returns></returns>
public Tuple<DirectedGraph<Region>, Region> BuildRegionGraph(Procedure proc)
{
var btor = new Dictionary<Block, Region>();
var regs = new DiGraph<Region>();
var regionFactory = new RegionFactory();
foreach (var b in proc.ControlGraph.Blocks)
{
if (b.Pred.Count == 0 && b != proc.EntryBlock ||
b == proc.ExitBlock)
continue;
var reg = regionFactory.Create(b);
btor.Add(b, reg);
regs.AddNode(reg);
}
foreach (var b in proc.ControlGraph.Blocks)
{
if (b.Pred.Count == 0 && b != proc.EntryBlock)
continue;
Region from;
btor.TryGetValue(b, out from);
foreach (var s in b.Succ)
{
if (s == proc.ExitBlock)
continue;
var to = btor[s];
regs.AddEdge(from, to);
}
if (from != null)
{
if (regs.Successors(from).Count == 0)
from.Type = RegionType.Tail;
}
}
foreach (var reg in regs.Nodes.ToList())
{
if (regs.Predecessors(reg).Count == 0 && reg != btor[proc.EntryBlock])
{
regs.Nodes.Remove(reg);
}
}
return new Tuple<DirectedGraph<Region>, Region>(regs, btor[proc.EntryBlock]);
}