From: adam <adam@megacz.com>
Date: Sun, 8 Jan 2006 05:51:26 +0000 (-0500)
Subject: intermediate checkpoint
X-Git-Tag: tag_for_25-Mar~418
X-Git-Url: http://git.megacz.com/?p=sbp.git;a=commitdiff_plain;h=526da96dd06e152d194ec92c9ef9df6085a1251b

intermediate checkpoint

darcs-hash:20060108055126-5007d-8d96906cc6e2efc0578d5ed26062dee848b63102.gz
---

diff --git a/src/edu/berkeley/sbp/Forest.java b/src/edu/berkeley/sbp/Forest.java
index ef420a8..e675f63 100644
--- a/src/edu/berkeley/sbp/Forest.java
+++ b/src/edu/berkeley/sbp/Forest.java
@@ -18,8 +18,7 @@ public abstract class Forest<T> {
 
     /** expand this forest into a set of trees */
     public abstract HashSet<Tree<T>>  expand(boolean toss);
-
-    abstract boolean valid();
+    public abstract boolean empty();
 
     static <T> Forest<T>   singleton(Token.Location loc, Sequence creator)                       { return create(loc, null, new Forest[] { }, creator, false, true); }
     static <T> Forest<T>   singleton(Token.Location loc, Forest<T> body, Sequence creator)       { return create(loc, null, new Forest[] { body }, creator, false, true); }
@@ -63,16 +62,15 @@ public abstract class Forest<T> {
                         b.expand(toss, toks, 0, h);
 
             } else {
-                if (tokens[i]!=null) {
-                    HashSet<Tree<T>> exp = tokens[i].expand(toss);
-                    if (exp != null)
-                        for(Tree<T> r : exp) {
-                            int old = toks.size();
-                            toks.add(r);
-                            expand(toss, toks, i+1, h);
-                            while(toks.size() > old) toks.remove(toks.size()-1);
-                        }
+                boolean hit = false;
+                for(Tree<T> r : tokens[i].expand(toss)) {
+                    hit = true;
+                    int old = toks.size();
+                    toks.add(r);
+                    expand(toss, toks, i+1, h);
+                    while(toks.size() > old) toks.remove(toks.size()-1);
                 }
+                //if (!hit) throw new Error();
             }
             return h;
         }
@@ -85,27 +83,6 @@ public abstract class Forest<T> {
             else for(Body b : (IterableForest<T>)tokens[0]) b.addTo(h);
         }
 
-        private boolean kcache = false;
-        private boolean keep = false;
-        public boolean keep() {
-            return true;
-            /*
-            if (kcache) return keep;
-            kcache = true;
-            for(Forest<T> token : tokens) if (!token.valid()) return keep = false;
-            return keep = creator==null || (creator.needs.size()==0 && creator.hates.size()==0);
-            */
-        }
-        public boolean keep(Iterable<Body<T>> h) {
-            if (keep()) return true;
-            for(Forest<T> token : tokens) if (!token.valid()) return false;
-            int needs = 0;
-            for(Body<T> b : h) {
-                if (creator.hates.contains(b.creator) && b.keep(h)) return false;
-                if (creator.needs.contains(b.creator) && b.keep(h)) needs--;
-            }
-            return needs <= -1 * creator.needs.size();
-        }
 
         private boolean rep = false;
         public String toString() {
@@ -143,53 +120,29 @@ public abstract class Forest<T> {
      *  viewed, it becomes immutable
      */
     static class Ref<T> extends IterableForest<T> {
+        public boolean empty() {
+            if (res!=null) return res.empty();
+            for(Forest f : hp) if (!f.empty()) return false;
+            return true;
+        }
         private FastSet<Forest> hp = new FastSet<Forest>();
         private Forest res = null;
-        public boolean valid = false;
         public Ref() { }
         public void merge(Forest p) {
-            //if (p==null) throw new Error("bad evil bad!");
             if (res != null) throw new Error("already resolved!");
             if (p==null) throw new Error();
             if (p!=this) hp.add(p, true);
         }
         public Iterator<Body<T>> iterator() { return ((IterableForest<T>)resolve()).iterator(); }
         public HashSet<Tree<T>> expand(boolean toss) { return resolve().expand(toss); }
-        public boolean valid() { return true; /*if (valid) return true; resolve(); return valid;*/ }
         public String toString() { return resolve().toString(); }
         public Forest resolve() {
             if (hp==null) return res;
             FastSet<Body> nh      = new FastSet<Body>();
-            /*
-            HashSet<Body> results = null;
-            for(Forest<?> p : hp)
-                for(Body<?> b : (IterableForest<?>)p) {
-                    if (b.keep() && (b.creator==null || !b.creator.lame)) {
-                        valid = true;
-                        b.addTo(nh);
-                    } else {
-                        results = new HashSet<Body>();
-                    }
-                }
-            if (results != null) {
-                for(Forest<?> p : hp)
-                    for(Body<?> b : (IterableForest<?>)p)
-                        results.add(b);
-                for(Body b : results) {
-                    if (b.keep() && (b.creator==null || !b.creator.lame)) continue;
-                    if (b.creator!=null && b.creator.lame) continue;
-                    if (!b.keep(results)) continue;
-                    valid = true;
-                    b.addTo(nh);
-                }
-            }
-            hp = null;
-            */
             for(Forest<?> p : hp)
                 for(Body<?> b : (IterableForest<?>)p)
-                    if (b.creator==null || !b.creator.lame)
-                        b.addTo(nh);
-            res = new MultiForest(nh, nh.size()>0);
+                    b.addTo(nh);
+            res = new MultiForest(nh);
             hp = null;
             return res;
         }
@@ -198,13 +151,11 @@ public abstract class Forest<T> {
     // Implementations //////////////////////////////////////////////////////////////////////////////
 
     private static class MultiForest<T> extends IterableForest<T> {
+        public boolean empty() { return results.size()>0; }
         private final FastSet<Body<T>> results;
-        private boolean valid;
-        public boolean valid() { /*return valid;*/ return true; }
-        private MultiForest(FastSet<Body<T>> results, boolean valid) { this.results = results; this.valid = valid; }
+        private MultiForest(FastSet<Body<T>> results) { this.results = results; }
         public MultiForest(Token.Location loc, T tag, Forest<T>[] tokens, Sequence creator, boolean unwrap, boolean singleton) {
             this.results = new FastSet<Body<T>>(new Body(loc, tag, tokens, creator, unwrap, singleton));
-            this.valid = true;
         }
         public Iterator<Body<T>> iterator() { return results.iterator(); }
 
diff --git a/src/edu/berkeley/sbp/GSS.java b/src/edu/berkeley/sbp/GSS.java
index 9ab6587..1adb8e4 100644
--- a/src/edu/berkeley/sbp/GSS.java
+++ b/src/edu/berkeley/sbp/GSS.java
@@ -18,8 +18,10 @@ class GSS {
     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> {
@@ -59,10 +61,12 @@ class GSS {
             this.token = token;
             this.location = location;
             inhibited.clear();
+            assumed.clear();
             reset();
         }
 
         public void reset() {
+            tail.clear();
             waiting.clear();
             performed.clear();
             hash = new HashMap<Long,Phase.Node>();
@@ -164,36 +168,42 @@ class GSS {
          *  @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) {
-            return newNode(parent, pending, state, fromEmptyReduction, null); }
-        public boolean newNode(Node parent, Forest pending, State state, boolean fromEmptyReduction, Reduction reduction) {
+            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, reduction.position.owner())) return false;
-                if (reduction.position.owner().needs != null) {
-                    for(Sequence s : reduction.position.owner().needs) {
+                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 false;
+                            return;
                         }
-                    }
-                }
-                if ((reduction.position.owner().needed != null && reduction.position.owner().needed.size()>0) ||
-                    (reduction.position.owner().hated != null && reduction.position.owner().hated.size()>0) ||
-                    (reduction.position.owner().hates != null && reduction.position.owner().hates.size()>0))
-                    performed.add(pos, reduction.position.owner());
+                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);
             }
-            Node p = hash.get(code(state, parent==null?null:parent.phase()));
-            boolean ret;
+            if (!owner.lame)
+                newNode(parent, pending, state, fromEmptyReduction);
             if (reduction!=null) inhibit(reduction, parent==null?0:parent.phase().pos);
-            if (p != null)  ret = newNode2(p, parent, pending, state, fromEmptyReduction, reduction);
-            else            ret = newNode3(parent, pending, state, fromEmptyReduction, reduction);
             if (reduction != null) {
                 boolean redo = true;
                 while(redo) {
                     redo = false;
-                    for(Waiting w : waiting.getAll(reduction.position.owner())) {
+                    for(Waiting w : waiting.getAll(owner)) {
                         if (w.parent==parent || (parent!=null&&w.parent!=null&&w.parent.phase()==parent.phase())) {
-                            waiting.remove(reduction.position.owner(), w);
+                            waiting.remove(owner, w);
                             w.perform();
                             redo = true;
                             break;
@@ -201,18 +211,15 @@ class GSS {
                     }
                 }
             }
-            return ret;
         }
-        private boolean newNode2(Node p, Node parent, Forest pending, State state, boolean fromEmptyReduction, Reduction reduction) {
+        private boolean newNode2(Node p, Node parent, Forest pending, State state, boolean fromEmptyReduction) {
             p.holder.merge(pending);
             if (p.parents().contains(parent)) return true;
-            //if (p.fe && p.phase() != parent.phase()) throw new Error("yep yep");
-            //if (!p.fe && p.phase() == parent.phase()) throw new Error("yep yep2");
             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, Reduction reduction) {
+        private boolean newNode3(Node parent, Forest pending, State state, boolean fromEmptyReduction) {
             do {
                 if (token != null && state.canShift(token)) break;
                 if (state.isAccepting()) break;
@@ -244,14 +251,15 @@ class GSS {
                 if (performed.contains(p,seq)) {
                     uninhibit(p, seq);
                     //System.out.println("\nresetting due to " + r.position.owner() + " killing " + seq);
-                    if (!reset) inhibited.add(p, seq);
+                    //inhibited.clear();
+                    inhibited.add(p, seq);
+                    //assumed = inhibited;
+                    //inhibited = new HashMapBag<Integer,Sequence>();
                     reset = true;
+                    resets++;
+                    throw new Reset();
                 }
-                if (!reset) inhibited.add(p, seq);
-            }
-            if (reset) {
-                resets++;
-                throw new Reset();
+                inhibited.add(p, seq);
             }
         }
         
@@ -274,6 +282,8 @@ class GSS {
                     reducing_list[i] = null;
                     n.queueReductions();
                 }
+                //for(Waiting w : tail)
+                //w.perform();
             } catch (Reset r) {
                 reset();
                 reduce();
@@ -294,13 +304,11 @@ class GSS {
             Forest res = null;
             boolean ok = false;
             for(Phase.Node n : hash.values()) {
-                if (n.holder==null) continue;
-                n.holder.resolve();
+                //if (n.holder().empty() && pos>0) continue;
                 if (token == null && n.state.isAccepting()) {
                     if (finalResult==null) finalResult = new Forest.Ref();
                     finalResult.merge(n.holder);
                 }
-                if (!n.holder.valid()) continue;
                 if (token == null) continue;
                 n.state.invokeShifts(token, this, result, n);
             }
@@ -389,20 +397,13 @@ class GSS {
             private Node(Node parent, Forest pending, State state, boolean fe) {
                 this.fe = fe;
                 this.state = state;
-                for(Position p : state) {
-                    if (p.owner().needs!=null)
-                        for(Sequence s : p.owner().needs) {
-                            //dead = true;
-                            //redo = false;
-                        }
-                }
+                this.holder().merge(pending);
+                //if (holder().empty()) throw new Error(holder()+"");
                 Phase start = parent==null ? null : parent.phase();
-                if (pending != null) this.holder().merge(pending);
                 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++;
-                if (parent==null) holder().valid = true; // hack to make sure that the "base" node is always considered valid
             }
         }
 
diff --git a/src/edu/berkeley/sbp/Parser.java b/src/edu/berkeley/sbp/Parser.java
index ead3551..c270a90 100644
--- a/src/edu/berkeley/sbp/Parser.java
+++ b/src/edu/berkeley/sbp/Parser.java
@@ -37,7 +37,7 @@ public abstract class Parser<T extends Token, R> {
         GSS gss = new GSS();
         Token.Location loc = input.getLocation();
         GSS.Phase current = gss.new Phase(null, this, null, input.next(1, 0, 0), loc, null);
-        current.newNode(null, null, pt.start, true);
+        current.newNode(null, Forest.leaf(null, null, null), pt.start, true);
         int count = 1;
         for(;;) {
             loc = input.getLocation();
@@ -382,6 +382,7 @@ public abstract class Parser<T extends Token, R> {
             }
             private void finish(GSS.Phase.Node parent, Forest result, GSS.Phase target) {
                 State state = parent.state.gotoSetNonTerminals.get(position.owner());
+                if (result==null) throw new Error();
                 if (state!=null)
                     target.newNode(parent, result, state, numPop<=0, this);
             }
diff --git a/src/edu/berkeley/sbp/Sequence.java b/src/edu/berkeley/sbp/Sequence.java
index 065150c..610af58 100644
--- a/src/edu/berkeley/sbp/Sequence.java
+++ b/src/edu/berkeley/sbp/Sequence.java
@@ -51,7 +51,7 @@ public abstract class Sequence extends Element implements Iterable<Element> {
           HashSet<Sequence> hated;
     final HashSet<Sequence> needs;
     final HashSet<Sequence> hates;
-          boolean           lame  = false;
+    public boolean           lame  = false;
 
     final Position          firstp;
     Position firstp() { return firstp; }
@@ -76,8 +76,7 @@ public abstract class Sequence extends Element implements Iterable<Element> {
     Forest epsilonForm() {
         if (epsilonForm==null) {
             epsilonForm = new Forest.Ref();
-            Forest fo = firstp().rewrite(null);
-            epsilonForm.merge(fo);
+            epsilonForm.merge(firstp().rewrite2(null));
         }
         return epsilonForm;
     }
@@ -122,8 +121,11 @@ public abstract class Sequence extends Element implements Iterable<Element> {
         // Reduction /////////////////////////////////////////////////////////////////////////////////
 
         final <T> Forest<T> rewrite(Token.Location loc) {
-            if (this==firstp() && eps) return epsilonForm;
-            eps = true;
+            if (this==firstp()) return epsilonForm();
+            return rewrite2(loc);
+        }
+
+        final <T> Forest<T> rewrite2(Token.Location loc) {
             for(int i=0; i<pos; i++) if (holder[i]==null) throw new Error("realbad " + i);
             for(int i=pos; i<elements.length; i++) {
                 if (holder[i]==null) holder[i] = elements[i].epsilonForm();
@@ -131,7 +133,6 @@ public abstract class Sequence extends Element implements Iterable<Element> {
             }
             Forest<T> ret = Sequence.this.postReduce(loc, holder);
             for(int k=0; k<pos; k++) holder[k] = null; // to help GC
-            if (this==firstp()) { if (epsilonForm==null) epsilonForm=new Forest.Ref(); epsilonForm.merge(ret); return epsilonForm; }
             return ret;
         }
 
diff --git a/src/edu/berkeley/sbp/misc/RegressionTests.java b/src/edu/berkeley/sbp/misc/RegressionTests.java
index b247021..a3d471d 100644
--- a/src/edu/berkeley/sbp/misc/RegressionTests.java
+++ b/src/edu/berkeley/sbp/misc/RegressionTests.java
@@ -85,6 +85,7 @@ public class RegressionTests {
             } catch (Parser.Failed pf) {
                 pfe = pf;
             }
+            //ystem.out.println("res=="+res);
             Collection<Tree<String>> results = res==null ? new HashSet<Tree<String>>() : res.expand(false);
             System.out.print("\r");
             if (results.size() == 0 && output.length > 0) {
diff --git a/tests/regression.tc b/tests/regression.tc
index 37a302e..e2ae422 100644
--- a/tests/regression.tc
+++ b/tests/regression.tc
@@ -262,20 +262,20 @@ testcase {
 
 
  while x>0
-   while y>0
-    foo()
-   bar()
+    while y>0
+       foo()
+          bar()
+
 
  while x>0
-   while y>0
-    foo()
-     bar()
+    while y>0
+          foo()
+        bar()
 
 
 
 ";
-     output "smt:{while:{>:{{x} {0}} sbb:{while:{>:{{y} {0}} {f o o}} {b a r}}} while:{>:{{x} {0}} while:{>:{{y} {0}} sbb:{{f o o} {b a r}}}}}";
-     output "smt:{while:{>:{{x} {0}} sbb:{while:{>:{{y} {0}} {f o o}} {b a r}}} while:{>:{{x} {0}} sbb:{while:{>:{{y} {0}} {f o o}} {b a r}}}}";
+  output "smt:{while:{>:{{x} {0}} while:{>:{{y} {0}} sbb:{{f o o} {b a r}}}} while:{>:{{x} {0}} sbb:{while:{>:{{y} {0}} {f o o}} {b a r}}}}";
 
 indent  !::= ww
 outdent !::= " "  outdent " "
@@ -293,7 +293,7 @@ block     ::= "\n" indent  blockBody
            &~ "\n" outdent ~[\ ] ~[]*
 
 blockBody ::= statement
-            | statement ws blockBody => "sbb"
+            > statement ws blockBody => "sbb"
 
 statement ::= call
             | ^"while" expr block /ws