/** implements Tomita's Graph Structured Stack */
class GSS {
- public static Queue<Node> removals = new LinkedList<Node>();
-
- static String note = "";
- static int single_newnode = 0;
- static int toplevel_reductions = 0;
- static int multi_newnode = 0;
- static int waiting_newnode = 0;
- static int shifts = 0;
-
- static int count = 0;
- static int reductions = 0;
- int resets = 0;
- int waits = 0;
-
Input input;
+ private Parser parser;
+ public GSS(Input input, Parser parser) { this.input = input; this.parser = parser;}
+ public Input getInput() { return input; }
- public GSS(Input input) { this.input = input; }
-
- private Node[] reducing_list = null;
-
- // FIXME: right now, these are the performance bottleneck
- HashMapBag<Sequence,Phase.Waiting> waiting = new HashMapBag<Sequence,Phase.Waiting>();
- HashMapBag<Integer,Sequence> performed = new HashMapBag<Integer,Sequence>();
- HashMapBag<Integer,Sequence> lastperformed = new HashMapBag<Integer,Sequence>();
- HashMapBag<Integer,Sequence> expected = new HashMapBag<Integer,Sequence>();
-
- /** FIXME */
- Forest.Many finalResult;
+ int numNewNodes = 0;
+ int numOldNodes = 0;
+ int viewPos = 0;
+ int numReductions = 0;
/** corresponds to a positions <i>between tokens</i> the input stream; same as Tomita's U_i's */
- class Phase<Tok> implements Invokable<State, Forest, Node>, IntegerMappable, GraphViz.ToGraphViz, Iterable<Node> {
+ class Phase<Tok> implements Invokable<State, Result>, IntegerMappable, GraphViz.ToGraphViz, Iterable<Node> {
- public int pos() { return pos; }
- public boolean closed() { return closed; }
- public Tok token() { return token; }
+ // FIXME: right now, these are the performance bottleneck
+ private HashMapBag<Integer,Sequence> performed = new HashMapBag<Integer,Sequence>();
- public Iterator<Node> iterator() { return hash.iterator(); }
- public void invoke(State st, Forest result, Node n) {
- shifts++;
- good |= next.newNode(n, result, st, false);
+ public Forest.Many finalResult;
+ private PriorityQueue<Reduction> reductionQueue = new PriorityQueue<Reduction>();
+
+ public void addReduction(Reduction r) {
+ //System.out.println("+ " + r);
+ parser.spin();
+ reductionQueue.add(r);
+ }
+ public void invoke(State st, Result result) {
+ parser.spin();
+ good |= next.newNode(result, st, false);
}
/** the token immediately after this phase */
final Tok token;
+ final int pos;
- private final int pos;
-
- boolean reducing;
- public IntPairMap<Node> hash; /* ALLOC */
- private boolean closed;
- private boolean good;
+ public IntPairMap<Node> hash = new IntPairMap<Node>(); /* ALLOC */
+ private boolean good = false;
private Phase next = null;
private Phase prev;
private Input.Location location;
private Input.Location nextLocation;
private Input.Location prevLocation;
- public final Parser parser;
-
private Forest forest;
- public Phase(Phase prev, Parser parser, Phase previous, Tok token, Input.Location location,
- Input.Location nextLocation, Forest forest) throws ParseFailed {
+ public Phase(State startState) throws ParseFailed, IOException {
+ this(null, null);
+ Result primordealResult = new Result(null, null, null);
+ newNode(primordealResult, startState, true);
+ }
+ public Phase(Phase prev, Forest forest) throws ParseFailed, IOException {
+ this.location = input.getLocation();
+ this.token = (Tok)input.next();
this.prevLocation = prev==null ? location : prev.getLocation();
this.prev = prev;
this.forest = forest;
- this.parser = parser;
- this.pos = previous==null ? 0 : previous.pos+1;
- this.token = token;
- this.location = location;
- this.nextLocation = nextLocation;
- performed.clear();
- reset();
- }
-
- public void reset() throws ParseFailed {
- waiting.clear();
- expected.clear();
- lastperformed.clear();
- lastperformed.addAll(performed);
- performed.clear();
- hash = new IntPairMap<Node>();
- reset = false;
- good = false;
- closed = false;
- reducing = false;
- finalResult = null;
+ this.pos = prev==null ? 0 : prev.pos+1;
+ this.nextLocation = input.getLocation();
if (prev != null) prev.shift(this, forest);
+ numReductions = 0;
+
+ int minPhasePos = Integer.MAX_VALUE;
+ int maxOrd = -1;
+ Reduction best = null;
+ //System.out.println("==============================================================================");
+ while(!reductionQueue.isEmpty()) {
+ Reduction r = reductionQueue.poll();
+ //System.out.println("- " + r);
+ if (r.parentPhase() != null)
+ if (r.parentPhase().pos > minPhasePos)
+ throw new Error();
+ r.perform();
+ if (r.parentPhase() != null) {
+ if (r.parentPhase().pos < minPhasePos) {
+ minPhasePos = r.parentPhase().pos;
+ maxOrd = r.reduction().ord;
+ best = r;
+ } else if (r.parentPhase().pos == minPhasePos) {
+ /*
+ if (best != null && Parser.mastercache.comparePositions(r.reduction(), best.reduction()) < 0)
+ throw new Error("\n"+r+"\n"+best+"\n"+
+ Parser.mastercache.comparePositions(r.reduction(), best.reduction())+"\n"+r.compareTo(best)+
+ "\n"+(r.reduction().ord-best.reduction().ord));
+ */
+ maxOrd = r.reduction().ord;
+ best = r;
+ }
+ }
+ numReductions++;
+ }
+ if (token==null) shift(null, null);
}
-
public boolean isDone() throws ParseFailed {
if (token != null) return false;
if (token==null && finalResult==null)
- ParseFailed.error("unexpected end of file",
- getLocation(),
- token,
- hash.values(),
- getLocation().createRegion(getLocation()),
- input,
- GSS.this);
+ ParseFailed.error("unexpected end of file", this);
return true;
}
public Input.Location getLocation() { return location; }
public Input.Region getRegion() { return getPrevLocation().createRegion(getLocation()); }
public Input.Location getNextLocation() { return nextLocation; }
+ public boolean isFrontier() { return hash!=null; }
- /** add a new node (merging with existing nodes if possible)
- * @param parent the parent of the new node
- * @param result the SPPF result corresponding to the new node
- * @param state the state that the new node is in
- * @param fromEmptyReduction true iff this node is being created as a result of a reduction of length zero (see GRMLR paper)
- * @param start the earliest part of the input contributing to this node (used to make merging decisions)
- */
- public boolean newNode(Node parent, Forest pending, State state, boolean fromEmptyReduction) {
- Node p = hash.get(state, parent==null?null:parent.phase());
- if (p != null) return newNode2(p, parent, pending, state, fromEmptyReduction);
- else return newNode3(parent, pending, state, fromEmptyReduction);
- }
- public void newNode(Node parent, Forest pending, State state, boolean fromEmptyReduction, Position reduction) {
- int pos = parent==null?0:parent.phase()==null?0:parent.phase().pos;
- Sequence owner = reduction==null ? null : reduction.owner();
- if (reduction!=null) {
- if (owner.hates!=null) {
- for (Sequence s : performed.getAll(pos))
- if (owner.hates.contains(s))
- return;
- for (Sequence s : lastperformed.getAll(pos))
- if (owner.hates.contains(s)) {
- //System.out.println("now expecting ["+pos+"] => " + s);
- expected.add(pos, s);
- return;
- }
- }
- if (owner.needs != null)
- for(Sequence s : owner.needs)
- if (!performed.contains(pos, s)) {
- waiting.add(s, new Waiting(parent, pending, state, fromEmptyReduction, reduction));
- return;
- }
- if (!performed.contains(pos, owner)) {
- performed.add(pos, owner);
- if (owner.hated != null)
- for(Sequence seq : owner.hated)
- if (performed.contains(pos, seq)) {
- performed.remove(pos, seq);
- reset = true;
- }
- }
+ /** perform all shift operations, adding promoted nodes to <tt>next</tt> */
+ private void shift(Phase next, Forest result) throws ParseFailed {
+ this.next = next;
+ // this massively improves GC performance
+ if (prev != null) {
+ IntPairMap<Node> h = prev.hash;
+ prev.hash = null;
+ prev.performed = null;
+ for(Node n : h)
+ n.check();
}
- newNode(parent, pending, state, fromEmptyReduction);
- if (reduction != null) {
- boolean redo = true;
- while(redo) {
- redo = false;
- for(Waiting w : waiting.getAll(owner)) {
- if (w.parent==parent || (parent!=null&&w.parent!=null&&w.parent.phase()==parent.phase())) {
- waiting.remove(owner, w);
- w.perform();
- redo = true;
- break;
- }
- }
+ numOldNodes = hash.size();
+ for(Node n : hash.values()) {
+ if (token == null && n.state().isAccepting()) {
+ if (finalResult==null) finalResult = new Forest.Many();
+ for(Result r : n)
+ finalResult.merge(r.getForest());
}
+ if (token == null) continue;
+ n.state().invokeShifts(token, this, new Result(result, n, null));
}
+ numNewNodes = next==null ? 0 : next.hash.size();
+ viewPos = this.pos;
+ if (!good && token!=null) ParseFailed.error("unexpected character", this);
+ if (token==null && finalResult==null) ParseFailed.error("unexpected end of file", this);
+ for(Node n : hash) n.check();
}
- private boolean newNode2(Node p, Node parent, Forest pending, State state, boolean fromEmptyReduction) {
- if (p.merge(parent, pending)) return true;
- p.addParent(parent, true);
- if (p!=parent && !fromEmptyReduction && reducing) p.performReductions(parent);
- return true;
+ void newNodeFromReduction(Result result, State state, Position reduction) {
+ int pos = result.phase().pos;
+ Sequence owner = reduction.owner();
+ for(Sequence s : owner.hates())
+ if (performed.contains(pos, s))
+ return;
+ for(Sequence s : owner.needs())
+ if (!performed.contains(pos, s))
+ return;
+ if (owner.needed_or_hated && !performed.contains(pos, owner))
+ performed.add(pos, owner);
+ if (state!=null)
+ newNode(result, state, reduction.pos<=0);
}
- private boolean newNode3(Node parent, Forest pending, State state, boolean fromEmptyReduction) {
+ /** add a new node (merging with existing nodes if possible)
+ * @param parent the parent of the new node
+ * @param result the SPPF result corresponding to the new node
+ * @param state the state that the new node is in
+ * @param fromEmptyReduction true iff this node is being created as a result of a reduction of length zero (see GRMLR paper)
+ * @param start the earliest part of the input contributing to this node (used to make merging decisions)
+ */
+ private boolean newNode(Result result, State state, boolean fromEmptyReduction) {
+ Node p = hash.get(state, result.phase());
+ if (p != null) { p.addResult(result); return true; }
do {
if (token != null && state.canShift(token)) break;
if (state.isAccepting()) break;
if (token==null) break;
if (!state.canReduce(token)) return false;
- //if (count > 1) break;
- //if (r.numPop == 0) break;
- //r.reduce(pending, parent, null, Phase.this, null);
- //return;
} while(false);
-
- Node n = new Node(Phase.this, parent, pending, state); // ALLOC
- if (reducing) {
- n.performEmptyReductions();
- if (!fromEmptyReduction) n.performReductions(parent);
- }
+ Node n = new Node(Phase.this, result, state, fromEmptyReduction); // ALLOC
+ for(Object s : state.also)
+ newNode(new Result(null, n, null), (State)s, fromEmptyReduction);
return true;
}
- public LinkedList<Node> reductionQueue = new LinkedList<Node>();
-
- /** perform all reduction operations */
- public void reduce() throws ParseFailed {
- try {
- reducing = true;
- if (reducing_list==null || reducing_list.length < hash.size())
- reducing_list = new Node[hash.size() * 4];
- hash.toArray(reducing_list);
- int num = hash.size();
- for(int i=0; i<num; i++) {
- Node n = reducing_list[i];
- n.performEmptyReductions();
- // INVARIANT: we never "see" a node until its parent-set is complete, modulo merges
- }
- for(int i=0; i<num; i++) {
- reductionQueue.add(reducing_list[i]);
- reducing_list[i] = null;
- }
- while(!reductionQueue.isEmpty()) {
- reductionQueue.remove().performReductions();
- }
- if (reset) {
- reset = false;
- resets++;
- throw new Reset();
- }
- for(int i : expected)
- for(Sequence s : expected.getAll(i))
- if (!performed.contains(i, s)) {
- //System.out.println("resetting due to pos="+i+": " + s + " " + System.identityHashCode(s));
- resets++;
- throw new Reset();
- }
- } catch (Reset r) {
- reset();
- reduce();
- }
- count = 0;
- }
-
- private boolean reset = false;
- class Reset extends RuntimeException { }
-
- /** perform all shift operations, adding promoted nodes to <tt>next</tt> */
- public void shift(Phase next, Forest result) throws ParseFailed {
- // this massively improves GC performance
- if (prev!=null && parser.helpgc) {
- //prev.hash = null;
- //System.out.println("\r" + /*shifts + " " + */ single_newnode /*+ "/"+multi_newnode + " " + waiting_newnode*/);
- //System.out.println("\r" + shifts + " " + note);
- //System.out.println("\r" + shifts);
- //System.out.println("\r" + toplevel_reductions);
- //System.out.println("\r" + multi_newnode);
- single_newnode = 0;
- note = "";
- multi_newnode = 0;
- toplevel_reductions = 0;
- waiting_newnode = 0;
- shifts = 0;
- }
- this.next = next;
- closed = true;
- Forest res = null;
- boolean ok = false;
- int count = 0;
- for(Node n : hash.values()) {
- if (token == null && n.state().isAccepting()) {
- if (finalResult==null) finalResult = new Forest.Many();
- for(Object f : n.results())
- finalResult.merge((Forest)f);
- }
- if (token == null) continue;
- n.state().invokeShifts(token, this, result, n);
- }
- //System.out.println(next.hash.size());
- if (!good && token!=null)
- ParseFailed.error("unexpected character",
- getLocation(),
- token,
- hash.values(),
- getRegion(),
- input,
- GSS.this);
-
- if (token==null && finalResult==null)
- ParseFailed.error("unexpected end of file",
- getLocation(),
- token,
- hash.values(),
- getLocation().createRegion(getLocation()),
- input,
- GSS.this);
- }
-
-
- class Waiting {
- Node parent;
- Forest pending;
- State state;
- boolean fromEmptyReduction;
- Position reduction;
- public Waiting(Node parent, Forest pending, State state, boolean fromEmptyReduction, Position reduction) {
- waits++;
- this.parent = parent;
- this.pending = pending;
- this.state = state;
- this.fromEmptyReduction = fromEmptyReduction;
- this.reduction = reduction;
- }
- public void perform() {
- //System.out.println("performing: " + reduction.position);
- waiting_newnode++;
- newNode(parent, pending, state, fromEmptyReduction, reduction);
- }
- }
-
-
public int toInt() { return pos+1; }
public int size() { return hash==null ? 0 : hash.size(); }
+ public int pos() { return pos; }
+ public Tok getToken() { return token; }
+ public Iterator<Node> iterator() { return hash.iterator(); }
+ public GSS getGSS() { return GSS.this; }
// GraphViz //////////////////////////////////////////////////////////////////////////////
public boolean isTransparent() { return false; }
public boolean isHidden() { return false; }
+ public void dumpGraphViz(String filename) throws IOException {
+ FileOutputStream fos = new FileOutputStream(filename);
+ PrintWriter p = new PrintWriter(new OutputStreamWriter(fos));
+ GraphViz gv = new GraphViz();
+ for(Object n : this)
+ ((Node)n).toGraphViz(gv);
+ gv.dump(p);
+ p.flush();
+ p.close();
+ }
+
}
}