- /** perform all reduction operations */
- public void reduce() throws ParseFailed {
- try {
- reducing = true;
- if (reducing_list==null || reducing_list.length < hash.size())
- reducing_list = new Phase.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++) {
- Node n = reducing_list[i];
- reducing_list[i] = null;
- n.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;
- }
- 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();
- for(Object f : n.results())
- finalResult.merge((Forest)f);
- }
- if (token == null) continue;
- n.state.invokeShifts(token, this, result, n);
- }
-
- if (!good && token!=null)
- throw new ParseFailed(ParseFailed.error(ANSI.red("unexpected character ")+" \'"+
- ANSI.purple(StringUtil.escapify(token+"", "\\\'\r\n"))+
- "\' encountered at "+
- ANSI.green(getLocation())+"\n", token, hash.values()),
- getLocation());
- if (token==null && finalResult==null)
- throw new ParseFailed(ParseFailed.error(ANSI.red("unexpected end of file\n"), token, hash.values()),
- getLocation());
- }
-
-
- 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);
- newNode(parent, pending, state, fromEmptyReduction, reduction);
- }
- }
-
- // Node /////////////////////////////////////////////////////////////////////////////////
-
- /** a node in the GSS */
- final class Node implements Invokable<Position, Node, Node>, IntegerMappable, GraphViz.ToGraphViz {
- public FastSet<Node> set = new FastSet<Node>();
-
- public GraphViz.Node toGraphViz(GraphViz gv) {
- if (gv.hasNode(this)) return gv.createNode(this);
- GraphViz.Node n = gv.createNode(this);
- n.label = ""+state.toStringx();
- n.shape = "rectangle";
- n.fill = "green";
- //GraphViz.Node f = pending().toGraphViz(gv);
- //n.add(f);
- for(Forest result : results()) n.edge(result, "");
- for(Node parent : parents()) n.edge(parent, "");
- ((GraphViz.Group)phase().toGraphViz(gv)).add(n);
- return n;
- }
- public boolean isTransparent() { return false; }
- public boolean isHidden() { return false; }
-
-
- //private Forest.Ref holder = new Forest.Ref();
- private boolean allqueued = false;
-
- /** what state this node is in */
- public final Parser.Table<Tok>.State<Tok> 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; }
- //private HashMap<Node,Forest> resultMap = new HashMap<Node,Forest>();
-
- private HashSet<Forest.Ref> resultMap = new HashSet<Forest.Ref>();
- public void merge(Node parent, Forest result) {
- for(Forest.Ref f : results()) {
- if (f.parents.contains(parent) && f.parents.size()==1) {
- f.merge(result);
- return;
- }
- }
- Forest.Ref f = new Forest.Ref();
- f.parents.add(parent);
- f.merge(result);
- resultMap.add(f);
- set.add(parent, true);
- /*
- Forest.Ref f = (Forest.Ref)resultMap.get(parent);
- if (f==null) { f = new Forest.Ref(); resultMap.put(parent, f); }
- f.merge(result);
- set.add(parent, true);
- */
- }
- public Iterable<Forest.Ref> results() { return resultMap; }
- //private Forest pending(Node n) {
- //return !Phase.this.closed ? holder : holder.resolve();
- /*
- for(Forest f : resultMap)
- if (resultMap.contains(f, n))
- return f;
- return null;
- */
- /*
- return resultMap.get(n);
- }
- */
- public FastSet<Node> parents() { return set; }
-
- public void performReductions() {
- if (allqueued) return;
- allqueued = true;
- state.invokeReductions(token, this, this, null);
- }
-
- public void performReductions(Node n2) {
- if (!allqueued) performReductions();
- else state.invokeReductions(token, this, this, n2);
- }
-
- public void performEmptyReductions() { state.invokeReductions(token, this, null, null); }
- public final void invoke(Position r, Node n, Node n2) {
- //if (r.owner().lame) return;
- 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(), holder);
- else n.reduce(r, r.pos-1, n.phase(), holder, null);
- } else {
- Forest[] holder = new Forest[r.pos];
- if (r.pos<=0) throw new Error("called wrong form of reduce()");
- int pos = r.pos-1;
- n.reduce(r, pos, n.phase(), holder, n2);
- }
- }
-
- public void reduce(Position r, int pos, Phase target, Forest[] holder, Node only) {
- Forest old = holder[pos];
-
- // FIXME: I'm unsure about this -- basically we want to deal with the case where
- // there are two nodes, each of whose Ref points to the same Forest instance.
- // Some node in the next phase has both of these as parents. This might happen
- // since the same reduction can appear in more than one state.
-
- for(Forest result : results())
- for(Node child : ((Forest.Ref<?>)result).parents) {
- if (only != null && child!=only) continue;
- holder[pos] = result;
- if (pos==0) {
- System.arraycopy(holder, 0, r.holder, 0, holder.length);
- for(int i=0; i<r.pos; i++) if (r.holder[i]==null) throw new Error("realbad");
- child.finish(r, r.rewrite(phase().getLocation()), target, holder);
- } else {
- child.reduce(r, pos-1, target, holder, null);
- }
- }
-
- holder[pos] = old;
- }
-
- public void finish(Position r, Forest result, Phase<Tok> target, Forest[] holder) {
- Parser.Table<Tok>.State<Tok> state0 = state.gotoSetNonTerminals.get(r.owner());
- if (result==null) throw new Error();
- if (state0!=null)
- target.newNode(this, result, state0, r.pos<=0, r);
- }
-
- private Node(Node parent, Forest pending, State state) {
- this.state = state;
- this.merge(parent, pending);
- Phase start = parent==null ? null : parent.phase();
- if (parent != null) parents().add(parent, true);
- if (Phase.this.hash.get(state, start) != null) throw new Error("severe problem!");
- Phase.this.hash.put(state, start, this);
- }
- public int toInt() { return idx; }
- private final int idx = node_idx++;
- }
- private int node_idx = 0;
-