1 // Copyright 2006-2007 all rights reserved; see LICENSE file for BSD-style license
3 package edu.berkeley.sbp;
4 import edu.berkeley.sbp.*;
5 import edu.berkeley.sbp.util.*;
6 import edu.berkeley.sbp.Parser.Table.*;
7 import edu.berkeley.sbp.Sequence.Pos;
8 import edu.berkeley.sbp.Sequence.Pos;
11 import java.lang.reflect.*;
13 /** a node in the GSS */
16 implements Invokable<Pos, ResultNode, Object>,
19 Iterable<ResultNode> {
21 /** which GSS.Phase this StateNode belongs to */
22 public GSS.Phase phase() { return phase; }
23 public Iterator<ResultNode> iterator() { return results.iterator(); }
24 public Parser.Table.State state() { return state; }
26 public int toInt() { return idx; }
28 boolean destroyed = false;
31 if (destroyed) return;
33 // - all nodes must have a predecessor
34 // - non-doomed nodes must either:
35 // - be on the frontier or
36 // - have a non-doomed node closer to the frontier than themself
37 if (phase.isFrontier()) dead = false;
38 else for(ResultNode r : successors)
39 if (state.doomed) { if (r.usedByAnyNode()) { dead = false; break; } }
40 else { if (r.usedByNonDoomedNode()) { dead = false; break; } }
41 dead |= results.size()==0;
44 if (phase() != null && phase().hash != null)
45 phase().hash.remove(state, predPhase);
46 while(successors.size()>0)
47 for(ResultNode r : successors) {
52 while(results.size()>0)
53 for(ResultNode r : results) {
62 //////////////////////////////////////////////////////////////////////
64 private static int node_idx = 0;
65 private final int idx = node_idx++;
67 private final GSS.Phase phase;
68 private final GSS.Phase predPhase;
69 private final Parser.Table.State state;
70 private boolean fromEmptyReduction;
71 private FastSet<ResultNode> results = new FastSet<ResultNode>();
72 private FastSet<ResultNode> successors = new FastSet<ResultNode>();
73 //private HashSet<ResultNode> results = new HashSet<ResultNode>();
74 //private HashSet<ResultNode> successors = new HashSet<ResultNode>();
76 public final void invoke(Pos r, ResultNode only, Object o) {
77 boolean emptyProductions = only==null;
78 if (emptyProductions != (r.numPops()==0)) return;
79 if (r.numPops()!=0) reduce(r, r.numPops()-1, phase(), only);
81 Input.Region region = phase().getLocation().createRegion(phase().getLocation());
82 phase().newNodeFromReduction(r.rewrite(region), r, this);
86 private void reduce(Pos r, int pos, GSS.Phase target, ResultNode only) {
87 for(ResultNode res : results)
88 if (only == null || res == only)
89 for(StateNode pred : res.getPreds())
90 reduce2(r, pos, target, pred, res.getForest());
93 void reduce2(Pos r, int pos, GSS.Phase target, StateNode pred, Forest f) {
94 Forest[] holder = r.holder;
95 Forest old = pos >= holder.length ? null : holder[pos];
96 if (pos < holder.length) holder[pos] = f;
97 if (pos>0) pred.reduce(r, pos-1, target, null);
99 Input.Region region = pred.phase().getLocation().createRegion(target.getLocation());
100 new Reduction(pred, r, r.rewrite(region), target);
102 if (pos < holder.length) holder[pos] = old;
105 StateNode(GSS.Phase phase, Forest f, Pos reduction, StateNode pred, State state, boolean fromEmptyReduction) {
106 this(phase, new ResultNode(f, reduction, pred), state, fromEmptyReduction);
108 StateNode(GSS.Phase phase, ResultNode pred, State state, boolean fromEmptyReduction) {
111 this.fromEmptyReduction = fromEmptyReduction;
112 if (phase.hash.get(state, pred.phase()) != null) throw new Error("severe problem!");
113 this.predPhase = pred.phase();
114 phase.hash.put(state, pred.phase(), this);
118 if (!fromEmptyReduction)
119 state.invokeReductions(phase().getToken(), this, pred);
121 state.invokeEpsilonReductions(phase().token, this);
124 // Add/Remove Successors/Results //////////////////////////////////////////////////////////////////////////////
126 public void removeSucc(ResultNode succ) {
127 successors.remove(succ);
130 public void removeResult(ResultNode result) {
131 results.remove(result);
134 public void addSucc(ResultNode succ) {
135 successors.add(succ);
137 public void addResult(Forest f, Pos reduction, StateNode pred) {
138 for(ResultNode r : results)
139 if (r.predecessorsContains(pred)) {
143 ResultNode result = new ResultNode(f, reduction, pred);
145 result.addSucc(this);
146 if (!this.fromEmptyReduction) state.invokeReductions(phase().getToken(), this, result);
149 // GraphViz //////////////////////////////////////////////////////////////////////////////
151 public GraphViz.StateNode toGraphViz(GraphViz gv) {
152 if (results.size()==0) return null;
153 if (gv.hasNode(this)) return gv.createNode(this);
154 GraphViz.StateNode n = gv.createNode(this);
155 n.label = "state["+state.toInt()+"]";
156 n.shape = "rectangle";
157 boolean haspreds = false;
158 for(ResultNode r : results) n.edge(r, "");
159 n.color = state.doomed ? "red" : "green";
160 ((GraphViz.Group)phase().toGraphViz(gv)).add(n);
163 public boolean isTransparent() { return false; }
164 public boolean isHidden() { return false; }