import java.lang.reflect.*;
/** a node in the GSS */
-final class Node implements Invokable<Position, Node, Node>, IntegerMappable, GraphViz.ToGraphViz {
-
- public static int node_idx = 0;
-
- private final GSS.Phase phase;
-
- public FastSet<Node> setx = new FastSet<Node>();
- public FastSet<Node> childs = new FastSet<Node>();
-
- private boolean allqueued = false;
-
- /** what state this node is in */
- public final Parser.Table.State state;
+final class Node
+ implements Invokable<Position, Result>,
+ IntegerMappable,
+ GraphViz.ToGraphViz,
+ Iterable<Result> {
+
+ /** which GSS.Phase this Node belongs to */
+ public GSS.Phase phase() { return phase; }
+ public Iterator<Result> iterator() { return results.iterator(); }
+ public Parser.Table.State state() { return state; }
- /** which GSS.Phase this Node belongs to (node that Node is also a non-static inner class of GSS.Phase) */
- public GSS.Phase phase() { return phase; }
+ public int toInt() { return idx; }
- private HashSet<Forest.Many> resultMap = new HashSet<Forest.Many>();
- public Iterable<Forest.Many> results() { return resultMap; }
- public Iterable<Node> parents() { return setx; }
- public void addParent(Node n, boolean b) {
- if (n==null) return;
- setx.add(n, b);
- n.childs.add(this, true);
- //else
- //System.out.println("************ evilstate: " + this);
- }
- public boolean merge(Node parent, Forest result) {
- // FIXME: inefficient!
- for(Forest.Many f : results()) {
- if (f.parents.contains(parent) /* UGLY: */ && f.parents.size()==1) {
- f.merge(result);
- return true;
+ boolean destroyed = false;
+
+ public void check() {
+ if (destroyed) return;
+ boolean dead = true;
+ // - all nodes must have a parent
+ // - non-doomed nodes must either:
+ // - be on the frontier or
+ // - have a non-doomed node closer to the frontier than themself
+ if (phase.isFrontier()) dead = false;
+ else for(Result r : children)
+ if (state.doomed) { if (r.usedByAnyNode()) { dead = false; break; } }
+ else { if (r.usedByNonDoomedNode()) { dead = false; break; } }
+ dead |= results.size()==0;
+ if (!dead) return;
+ destroyed = true;
+ while(children.size()>0)
+ for(Result r : children) {
+ children.remove(r);
+ r.destroy();
+ break;
}
- }
- Forest.Many f = new Forest.Many();
- f.parents.add(parent);
- f.merge(result);
- resultMap.add(f);
- addParent(parent, true);
- return false;
- }
-
- public void performReductions() {
- if (allqueued) return;
- allqueued = true;
- state.invokeReductions(phase().token(), this, this, null);
+ while(results.size()>0)
+ for(Result r : results) {
+ results.remove(r);
+ r.removeChild(this);
+ break;
+ }
+ results = null;
+ children = null;
}
- public void performReductions(Node n2) {
- if (!allqueued) phase().reductionQueue.add(this);//performReductions();
- else state.invokeReductions(phase().token(), this, this, n2);
- }
+ //////////////////////////////////////////////////////////////////////
- public Parser.Table.State state() { return state; }
+ private static int node_idx = 0;
+ private final int idx = node_idx++;
- public void performEmptyReductions() { state.invokeReductions(phase().token, this, null, null); }
- public final void invoke(Position r, Node n, Node n2) {
- //reductions++;
- //if (r.pos==1) single_newnode++;
- //if (r.pos>1) multi_newnode++;
- if (n==null || n2==null || r.pos==0) {
- if (r.pos==0) {
- if (n==null) n = this;
- else return;
- }
- if (n==null) return;
- Forest[] holder = new Forest[r.pos];
- if (r.pos==0) n.finish(r, r.zero(n.phase().getLocation().createRegion(n.phase().getLocation())), n.phase());
- else n.reduce(r, r.pos-1, n.phase(), null);
- } else {
- if (r.pos<=0) throw new Error("called wrong form of reduce()");
- int pos = r.pos-1;
- n.reduce(r, pos, n.phase(), n2);
+ private final GSS.Phase phase;
+ private final Parser.Table.State state;
+ private final boolean fromEmptyReduction;
+ //private FastSet<Result> results = new FastSet<Result>();
+ private HashSet<Result> results = new HashSet<Result>();
+ private HashSet<Result> children = new HashSet<Result>();
+
+ public final void invoke(Position r, Result only) {
+ boolean emptyProductions = only==null;
+ if (emptyProductions != (r.pos==0)) return;
+ if (r.pos!=0) reduce(r, r.pos-1, phase(), only);
+ else {
+ Input.Region region = phase().getLocation().createRegion(phase().getLocation());
+ new Result(r.rewrite(region, phase().parser().cache()), this, r, phase());
}
}
- public void reduce(Position r, int pos, GSS.Phase target, Node only) {
+ private void reduce(Position r, int pos, GSS.Phase target, Result only) {
Forest[] holder = r.holder;
Forest old = holder[pos];
-
- //toplevel_reductions++;
- HashSet<Forest> rr = new HashSet<Forest>();
- for(Forest result : results()) {
- rr.add(result);
- }
- //System.out.println(r);
- for(Forest result : rr) {
- for(Node child : ((Forest.Many<?>)result).parents) {
- if (only != null && child!=only) continue;
- holder[pos] = result;
- if (pos==0) child.finish(r, r.rewrite(child.phase().getLocation().createRegion(target.getLocation())), target);
- else child.reduce(r, pos-1, target, null);
+ if (results==null) return; // FIXME: this should not happen
+ for(Result res : results)
+ if (only == null || res == only) {
+ Node child = res.parent();
+ holder[pos] = res.getForest();
+ if (pos>0) child.reduce(r, pos-1, target, null);
+ else {
+ Input.Region region = child.phase().getLocation().createRegion(target.getLocation());
+ new Reduction(child, r, r.rewrite(region, phase().parser().cache()), target);
+ }
}
- }
holder[pos] = old;
}
- public void finish(Position r, Forest result, GSS.Phase target) {
- Parser.Table.State state0 = (Parser.Table.State)state.gotoSetNonTerminals.get(r.owner());
- if (result==null) throw new Error();
- if (state0!=null)
- target.newNode(this, result, state0, r.pos<=0, r);
- }
-
- Node(GSS.Phase phase, Node parent, Forest pending, State state) {
+ Node(GSS.Phase phase, Result result, State state, boolean fromEmptyReduction) {
this.phase = phase;
this.state = state;
- this.merge(parent, pending);
- GSS.Phase start = parent==null ? null : parent.phase();
- if (parent != null) addParent(parent, true);
- if (phase.hash.get(state, start) != null) throw new Error("severe problem!");
- phase.hash.put(state, start, this);
+ this.fromEmptyReduction = fromEmptyReduction;
+ if (phase.hash.get(state, result.phase()) != null) throw new Error("severe problem!");
+ phase.hash.put(state, result.phase(), this);
+ addResult(result);
+ state.invokeEpsilonReductions(phase().token, this);
+ }
+
+ // Add/Remove Children/Results //////////////////////////////////////////////////////////////////////////////
+
+ public void removeChild(Result child) {
+ if (children==null) return;
+ children.remove(child);
+ check();
+ }
+ public void removeResult(Result result) {
+ if (results==null) return;
+ results.remove(result);
+ check();
+ }
+ public void addChild(Result child) {
+ if (children==null) return; // FIXME: this should not happen
+ children.add(child);
+ }
+ public void addResult(Result r) {
+ if (results.contains(r)) return;
+ results.add(r);
+ r.addChild(this);
+ if (!fromEmptyReduction) state.invokeReductions(phase().getToken(), this, r);
}
- public int toInt() { return idx; }
- private final int idx = node_idx++;
// GraphViz //////////////////////////////////////////////////////////////////////////////
public GraphViz.Node toGraphViz(GraphViz gv) {
+ if (results.size()==0) return null;
if (gv.hasNode(this)) return gv.createNode(this);
GraphViz.Node n = gv.createNode(this);
- n.label = ""+state.toStringx();
+ n.label = "state["+state.toInt()+"]";
n.shape = "rectangle";
boolean hasparents = false;
- for(Node parent : parents()) { hasparents = true; n.edge(parent, ""); }
- for(Forest result : results()) n.edge(result, "");
- n.color = !hasparents ? "blue" : /*state.evil ? "red" :*/ "green";
+ for(Result r : results) n.edge(r, "");
+ n.color = state.doomed ? "red" : "green";
((GraphViz.Group)phase().toGraphViz(gv)).add(n);
return n;
}
projects / sbp.git / blobdiff