/** implements Tomita's Graph Structured Stack */
class GSS {
+ public static int count = 0;
public GSS() { }
private Phase.Node[] reducing_list = null;
public int resets = 0;
public int waits = 0;
- HashMapBag<Integer,Sequence> inhibited = new HashMapBag<Integer,Sequence>();
- HashMapBag<Integer,Sequence> expectedInhibit = new HashMapBag<Integer,Sequence>();
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 */
public Forest.Ref finalResult;
/** corresponds to a positions <i>between tokens</i> the input stream; same as Tomita's U_i's */
- public class Phase<Tok> implements Invokable<State, Forest, Phase<Tok>.Node>, IntegerMappable {
+ class Phase<Tok> implements Invokable<State, Forest, Phase<Tok>.Node>, IntegerMappable {
public void invoke(State st, Forest result, Node n) {
good |= next.newNode(n, result, st, false);
this.pos = previous==null ? 0 : previous.pos+1;
this.token = token;
this.location = location;
- inhibited.clear();
+ performed.clear();
reset();
}
public void reset() throws ParseFailed {
waiting.clear();
+ expected.clear();
+ lastperformed.clear();
+ lastperformed.addAll(performed);
performed.clear();
hash = new IntPairMap<Phase.Node>();
singularReductions = new IntPairMap<Forest>();
- expectedInhibit.clear();
- expectedInhibit.addAll(inhibited);
+ reset = false;
good = false;
closed = false;
reducing = false;
int pos = parent==null?0:parent.phase()==null?0:parent.phase().pos;
Sequence owner = reduction==null ? null : reduction.owner();
if (reduction!=null) {
- if (inhibited.contains(pos, owner)) return;
+ 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 ((owner.needed != null && owner.needed.size()>0) ||
- (owner.hated != null && owner.hated.size()>0) ||
- (owner.hates != null && owner.hates.size()>0))
+ 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;
+ }
+ }
}
if (!owner.lame)
newNode(parent, pending, state, fromEmptyReduction);
- if (reduction!=null) inhibit(reduction, parent==null?0:parent.phase().pos);
if (reduction != null) {
boolean redo = true;
while(redo) {
return true;
}
- public void uninhibit(int p, Sequence s) {
- if (s.hated!=null)
- for(Sequence s2 : s.hated)
- inhibited.remove(p, s2);
- }
-
- public void inhibit(Position r, int p) {
- if (r.owner().hated == null) return;
- // remember that dead states are still allowed to shift -- just not allowed to reduce
- boolean reset = false;
- for(Sequence seq : r.owner().hated) {
- if (performed.contains(p,seq)) {
- uninhibit(p, seq);
- //System.out.println("\nresetting due to " + r.owner() + " killing " + seq);
- //inhibited.clear();
- inhibited.add(p, seq);
- //inhibited = new HashMapBag<Integer,Sequence>();
- reset = true;
- resets++;
- throw new Reset();
- }
- inhibited.add(p, seq);
- expectedInhibit.remove(p, seq);
- }
- }
-
/** perform all reduction operations */
- public void reduce() throws ParseFailed{
+ public void reduce() throws ParseFailed {
try {
reducing = true;
if (reducing_list==null || reducing_list.length < hash.size())
reducing_list[i] = null;
n.performReductions();
}
- if (expectedInhibit.size() > 0) {
- inhibited.removeAll(expectedInhibit);
- System.out.println("\n!!!!\n");
+ 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 class Waiting {
+ class Waiting {
Node parent;
Forest pending;
State state;
// Node /////////////////////////////////////////////////////////////////////////////////
/** a node in the GSS */
- public final class Node extends FastSet<Node> implements Invokable<Position, Node, Node>, IntegerMappable {
+ final class Node extends FastSet<Node> implements Invokable<Position, Node, Node>, IntegerMappable {
private Forest.Ref holder = null;
private boolean allqueued = false;