+// Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
+
package edu.berkeley.sbp;
import edu.berkeley.sbp.*;
import edu.berkeley.sbp.util.*;
+import edu.berkeley.sbp.Parser.Table.*;
import edu.berkeley.sbp.Sequence.Position;
-import edu.berkeley.sbp.Parser.Table.State;
-import edu.berkeley.sbp.Parser.Table.Reduction;
import java.io.*;
import java.util.*;
import java.lang.reflect.*;
/** implements Tomita's Graph Structured Stack */
class GSS {
- 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> assumed = new HashMapBag<Integer,Sequence>();
- HashMapBag<Sequence,Phase.Waiting> waiting = new HashMapBag<Sequence,Phase.Waiting>();
- HashMapBag<Integer,Sequence> performed = new HashMapBag<Integer,Sequence>();
- HashSet<Phase.Waiting> tail = new HashSet<Phase.Waiting>();
-
- /** corresponds to a positions <i>between tokens</i> the input stream; same as Tomita's U_i's */
- public class Phase implements Invokable<State, Forest, GSS.Phase.Node>, IntegerMappable {
- public int toInt() { return pos+1; }
-
- /** the token immediately after this phase */
- public final Token token;
+ Input input;
+ public GSS(Input input) { this.input = input; }
+ public Input getInput() { return input; }
- boolean reducing;
+ // FIXME: right now, these are the performance bottleneck
+ HashMapBag<Integer,Sequence> performed = new HashMapBag<Integer,Sequence>();
- /** currently this is necessary only for the code() hack -- it doesn't actually correspond to the input */
- private final int pos;
+ /** FIXME */
+ Forest.Many finalResult;
- /** FIXME */
- public Forest.Ref finalResult;
+ /** corresponds to a positions <i>between tokens</i> the input stream; same as Tomita's U_i's */
+ class Phase<Tok> implements Invokable<State, Result, Object>, IntegerMappable, GraphViz.ToGraphViz, Iterable<Node> {
- /** all nodes, keyed by the value returned by code() */
- /*private*/ HashMap<Long,Phase.Node> hash; /* ALLOC */
+ public PriorityQueue<Reduction> reductionQueue = new PriorityQueue<Reduction>();
- /** the number of nodes in this phase */
- private int numNodes;
+ public void invoke(State st, Result result, Object o) {
+ //shifts++;
+ good |= next.newNode(result, st, false);
+ }
- boolean closed;
+ /** the token immediately after this phase */
+ final Tok token;
+ final int pos;
+ public IntPairMap<Node> hash; /* ALLOC */
private boolean good;
private Phase next = null;
-
- private Token.Location location;
- public final Parser parser;
-
+ private Phase prev;
+ private Input.Location location;
+ private Input.Location nextLocation;
+ private Input.Location prevLocation;
+
private Forest forest;
- Phase prev;
- public Phase(Phase prev, Parser parser, Phase previous, Token token, Token.Location location, Forest forest) {
+
+ public Phase(Phase prev, Phase previous, Tok token, Input.Location location,
+ Input.Location nextLocation, Forest forest) throws ParseFailed {
+ 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;
- inhibited.clear();
- assumed.clear();
- reset();
- }
-
- public void reset() {
- tail.clear();
- waiting.clear();
+ this.nextLocation = nextLocation;
performed.clear();
- hash = new HashMap<Long,Phase.Node>();
+ hash = new IntPairMap<Node>();
good = false;
- closed = false;
- numNodes = 0;
- reducing = false;
finalResult = null;
if (prev != null) prev.shift(this, forest);
}
- public void complain(Node n, HashMap<String,HashSet<String>> errors, boolean force) {
- if (n.touched) return;
- n.touched = true;
- for(Position p : n.state) {
- //if (!p.isLast()) {
- if (((p.isFirst() || p.isLast()) && !force) || p.owner().name==null) {
- for(Node n2 : n.parents())
- complain(n2, errors, force | p.isFirst());
- } else {
- String seqname = p.owner().name;
- HashSet<String> hs = errors.get(seqname);
- if (hs==null) errors.put(seqname, hs = new HashSet<String>());
- hs.add(p.element()+"");
- //String s = " while parsing " + seqname + ": expected a " + p.element();
- //"\n";
- /*
- s += " parsed: ";
- for(Position p2 = p.owner().firstp(); p2 != null && p2 != p && !p2.isLast(); p2 = p2.next()) s += (p2.element() + " ");
- s += "\n";
- s += " expected: ";
- for(Position p2 = p; p2 != null && !p2.isLast(); p2 = p2.next()) s += (p2.element() + " ");
- */
- //s += "\n";
- //errors.add(s);
- }
- }
+ public boolean isFrontier() { return next==null; }
+ public boolean isDone() throws ParseFailed {
+ if (token != null) return false;
+ if (token==null && finalResult==null)
+ ParseFailed.error("unexpected end of file", this);
+ return true;
}
- public String black(Object o) { return "\033[30m"+o+"\033[0m"; }
- public String red(Object o) { return "\033[31m"+o+"\033[0m"; }
- public String green(Object o) { return "\033[32m"+o+"\033[0m"; }
- public String yellow(Object o) { return "\033[33m"+o+"\033[0m"; }
- public String blue(Object o) { return "\033[34m"+o+"\033[0m"; }
- public String purple(Object o) { return "\033[35m"+o+"\033[0m"; }
- public String cyan(Object o) { return "\033[36m"+o+"\033[0m"; }
- public String el(Object e) {
- String s = e.toString();
- if (s.length()==0 || s.charAt(0)!='\"' || s.charAt(s.length()-1)!='\"') return yellow(s);
- s = s.substring(1);
- s = s.substring(0, s.length()-1);
- StringBuffer ret = new StringBuffer();
- for(int i=0; i<s.length(); i++) {
- if (s.charAt(i)=='\\' && i<s.length()-1) ret.append(s.charAt(++i));
- else ret.append(s);
- }
- return purple(ret.toString());
- }
- public String error(String message) {
- String lookAhead = token==null ? "<EOF>" : token.toString();
- StringBuffer ret = new StringBuffer();
- ret.append("\n ");
- ret.append(message);
- HashMap<String,HashSet<String>> errors = new HashMap<String,HashSet<String>>();
- for(Node n : hash.values()) complain(n, errors, false);
- for(String s : errors.keySet()) {
- ret.append(" while parsing " + yellow(s));
- HashSet<String> hs = errors.get(s);
- if (hs.size()==1) ret.append(" expected " + yellow(el(hs.iterator().next())) + "\n");
- else {
- ret.append(" expected ");
- boolean first = true;
- for(String s2 : hs) {
- if (!first) ret.append(" or ");
- first = false;
- ret.append(yellow(el(s2)));
- }
- ret.append("\n");
+ public Input.Location getPrevLocation() { return prevLocation; }
+ public Input.Location getLocation() { return location; }
+ public Input.Region getRegion() { return getPrevLocation().createRegion(getLocation()); }
+ public Input.Location getNextLocation() { return nextLocation; }
+
+ /** 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) prev.hash = null;
+ this.next = next;
+ 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), null);
}
- return ret.toString();
+ for(Node n : hash.values()) n.check();
+ if (!good && token!=null) ParseFailed.error("unexpected character", this);
+ if (token==null && finalResult==null) ParseFailed.error("unexpected end of file", this);
}
-
- public boolean isDone() throws Parser.Failed {
- if (token != null) return false;
- if (token==null && finalResult==null)
- throw new Parser.Failed(error(red("unexpected end of file\n")),
- getLocation());
- return true;
+
+ /** perform all reduction operations */
+ public void reduce() throws ParseFailed {
+ while(!reductionQueue.isEmpty())
+ reductionQueue.poll().perform();
}
- public Token.Location getLocation() { return location; }
+ public void newNodeFromReduction(Result result, State state, boolean fromEmptyReduction, 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, fromEmptyReduction);
+ }
/** add a new node (merging with existing nodes if possible)
* @param parent the parent of the new node
* @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(code(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, Reduction reduction) {
- int pos = parent==null?0:parent.phase()==null?0:parent.phase().pos;
- Sequence owner = reduction==null ? null : reduction.position.owner();
- if (reduction!=null) {
- if (inhibited.contains(pos, owner)) return;
- /*
- if (assumed.contains(pos, owner)) {
- tail.add(new Waiting(parent, pending, state, fromEmptyReduction, reduction));
- 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))
- performed.add(pos, owner);
- }
- 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) {
- 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;
- }
- }
- }
- }
- }
- private boolean newNode2(Node p, Node parent, Forest pending, State state, boolean fromEmptyReduction) {
- p.holder.merge(pending);
- if (p.parents().contains(parent)) return true;
- p.parents().add(parent, true);
- if (p!=parent && !fromEmptyReduction) p.queueReductions(parent);
- return true;
- }
- private boolean newNode3(Node parent, Forest pending, State state, boolean fromEmptyReduction) {
+ public boolean newNode(Result result, State state, boolean fromEmptyReduction) {
+ Node p = hash.get(state, result.phase());
+ if (p != null) { p.merge(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;
+ if (!state.canReduce(token)) return false;
} while(false);
-
- Node n = new Node(parent, pending, state, fromEmptyReduction); // ALLOC
- n.queueEmptyReductions();
- if (!fromEmptyReduction) n.queueReductions(parent);
+ new Node(Phase.this, result, state, fromEmptyReduction); // ALLOC
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(Reduction r, int p) {
- if (r.position.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.position.owner().hated) {
- if (performed.contains(p,seq)) {
- uninhibit(p, seq);
- //System.out.println("\nresetting due to " + r.position.owner() + " killing " + seq);
- //inhibited.clear();
- inhibited.add(p, seq);
- //assumed = inhibited;
- //inhibited = new HashMapBag<Integer,Sequence>();
- reset = true;
- resets++;
- throw new Reset();
- }
- inhibited.add(p, seq);
- }
- }
-
- /** perform all reduction operations */
- public void reduce() {
- try {
- reducing = true;
- if (reducing_list==null || reducing_list.length < hash.size())
- reducing_list = new Phase.Node[hash.size() * 4];
- Collection<Node> hv = hash.values();
- hv.toArray(reducing_list);
- int num = hv.size();
- for(int i=0; i<num; i++) {
- Node n = reducing_list[i];
- n.queueEmptyReductions();
- // INVARIANT: we never "see" a node until its parent-set is complete, modulo merges
- }
- for(int i=0; i<num; i++) {
- Node n = reducing_list[i];
- reducing_list[i] = null;
- n.queueReductions();
- }
- //for(Waiting w : tail)
- //w.perform();
- } catch (Reset r) {
- reset();
- reduce();
- }
- }
-
- class Reset extends RuntimeException { }
-
- public void invoke(State st, Forest result, Node n) {
- good |= next.newNode(n, result, st, false);
- }
-
- /** perform all shift operations, adding promoted nodes to <tt>next</tt> */
- public void shift(Phase next, Forest result) throws Parser.Failed {
- if (prev!=null) prev.hash = null;
- this.next = next;
- closed = true;
- Forest res = null;
- boolean ok = false;
- for(Phase.Node n : hash.values()) {
- if (token == null && n.state.isAccepting()) {
- if (finalResult==null) finalResult = new Forest.Ref();
- finalResult.merge(n.holder);
- }
- if (token == null) continue;
- n.state.invokeShifts(token, this, result, n);
- }
-
- if (!good && token!=null)
- throw new Parser.Failed(error(red("unexpected character")+" "+purple(token)+" encountered at "+green(getLocation())+"\n"),
- getLocation());
- if (token==null && finalResult==null)
- throw new Parser.Failed(error(red("unexpected end of file\n")),
- getLocation());
-
- // this massively improves GC performance
- //hash = null;
- }
-
-
- public class Waiting {
- Node parent;
- Forest pending;
- State state;
- boolean fromEmptyReduction;
- Reduction reduction;
- public Waiting(Node parent, Forest pending, State state, boolean fromEmptyReduction, Reduction 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);
- newNode(parent, pending, state, fromEmptyReduction, reduction);
- }
- }
-
- // GSS Nodes //////////////////////////////////////////////////////////////////////////////
-
- /** a node in the GSS */
- public final class Node extends FastSet<Node> implements Invokable<Reduction, Node, Node> {
-
- public boolean touched = false;
- private Forest.Ref holder = null;
- private boolean allqueued = false;
-
- /** what state this node is in */
- public final State state;
-
- /** which Phase this Node belongs to (node that Node is also a non-static inner class of Phase) */
- public Phase phase() { return Phase.this; }
-
- public Forest.Ref holder() { return holder==null ? (holder = new Forest.Ref()) : holder; }
- public Forest pending() { return Phase.this.closed ? holder().resolve() : holder; }
- public FastSet<Node> parents() { return this; }
-
- public void queueReductions() {
- if (!reducing) return;
- if (allqueued) return;
- allqueued = true;
- int where = parents().size();
- state.invokeReductions(token, this, this, null);
- }
-
- public void queueReductions(Node n2) {
- if (!allqueued) { queueReductions(); return; }
- state.invokeReductions(token, this, this, n2);
- }
+ 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; }
- public final void invoke(Reduction r, Node n, Node n2) {
- if (n==null) {
- if (r.numPop==0) r.reduce(this);
- return;
- }
- if (r.numPop==0) return;
- if (n2==null) r.reduce(n);
- else r.reduce(n, n2);
- }
- public void queueEmptyReductions() {
- if (!reducing) return;
- state.invokeReductions(token, this, null, null);
- }
+ // GraphViz //////////////////////////////////////////////////////////////////////////////
- private boolean fe;
- public boolean dead = false;
- public boolean redo = false;
- private Node(Node parent, Forest pending, State state, boolean fe) {
- this.fe = fe;
- this.state = state;
- this.holder().merge(pending);
- Phase start = parent==null ? null : parent.phase();
- if (parent != null) parents().add(parent, true);
- if (Phase.this.hash.get(code(state, start)) != null) throw new Error("severe problem!");
- Phase.this.hash.put(code(state, start), this);
- Phase.this.numNodes++;
- }
+ public GraphViz.Node toGraphViz(GraphViz gv) {
+ if (gv.hasNode(this)) return gv.createNode(this);
+ GraphViz.Group g = gv.createGroup(this);
+ g.label = "Phase " + pos;
+ g.color = "gray";
+ g.cluster = true;
+ return g;
}
+ public boolean isTransparent() { return false; }
+ public boolean isHidden() { return false; }
}
- /** helper method */
- private static boolean equal(Object a, Object b) {
- if (a==null && b==null) return true;
- if (a==null || b==null) return false;
- return a.equals(b);
- }
-
- /** this is something of a hack right now */
- private static long code(State state, Phase start) {
- return (((long)state.idx) << 32) | (start==null ? 0 : (start.pos+1));
- }
}