Mercurial > lcfOS
view python/interferencegraph.py @ 288:a747a45dcd78
Various styling work
author | Windel Bouwman |
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date | Thu, 21 Nov 2013 14:26:13 +0100 |
parents | 02385f62f250 |
children |
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import graph class InterferenceGraphNode(graph.Node): def __init__(self, g, varname): super().__init__(g) self.temps = [varname] self.moves = set() self.color = None def __repr__(self): return '{}({})'.format(self.temps, self.color) class InterferenceGraph(graph.Graph): """ Interference graph. """ def __init__(self, flowgraph): """ Create a new interference graph from a flowgraph """ super().__init__() # Calculate liveness in CFG: ### # Liveness: # in[n] = use[n] UNION (out[n] - def[n]) # out[n] = for s in n.succ in union in[s] ### for n in flowgraph.nodes: n.live_in = set() n.live_out = set() # Dataflow fixed point iteration: change = True while change: change = False for n in flowgraph.nodes: _in = n.live_in _out = n.live_out n.live_in = n.uses | (n.live_out - n.defs) if n.Succ: n.live_out = set.union(*(s.live_in for s in n.Succ)) else: n.live_out = set() change = change or (_in != n.live_in) or (_out != n.live_out) # Construct interference graph: for n in flowgraph.nodes: for tmp in n.live_out: n1 = self.getNode(tmp) for tmp2 in (n.live_out - {tmp}): n2 = self.getNode(tmp2) self.addEdge(n1, n2) def to_dot(self, f): """ Generate graphviz dot representation """ for node in self.nodes: print('{} [label="{}" shape=box3d];'.format(id(node), node), file=f) for n, m in self.edges: print('{} -> {};'.format(id(n), id(m)), file=f) def to_txt(self): for node in self.nodes: print('{} interferes: {}'.format(node, node.Adjecent)) def getNode(self, tmp): # Linear search # TODO: can be improved for speed! for n in self.nodes: if tmp in n.temps: return n n = InterferenceGraphNode(self, tmp) self.addNode(n) return n def Combine(self, n, m): """ Combine n and m into n """ n.temps.extend(m.temps) n.moves.update(m.moves) # Reroute all edges: e1 = [e for e in self.edges if e[0] is m] e2 = [e for e in self.edges if e[1] is m] for e in e1: self.edges.remove(e) self.addEdge(n, e[1]) for e in e2: self.edges.remove(e) self.addEdge(n, e[0]) # Remove node m: self.delNode(m)