X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FGSS.java;h=645fa8ff6f290d7750f382b7b04f0c7141158307;hp=6db929bb8893f33fde1ff7f70c87b18665b729b4;hb=c4431d19cc5ddaae29d22c8c56366b53b0bad352;hpb=f169adc2b98fc4034d67bab4dd2938fb2f15e5c4

diff --git a/src/edu/berkeley/sbp/GSS.java b/src/edu/berkeley/sbp/GSS.java
index 6db929b..645fa8f 100644
--- a/src/edu/berkeley/sbp/GSS.java
+++ b/src/edu/berkeley/sbp/GSS.java
@@ -35,6 +35,8 @@ class GSS {
         /** the token immediately after this phase */
         public  final Token token;
 
+        boolean reducing = false;
+
         /** currently this is necessary only for the code() hack -- it doesn't actually correspond to the input */
         private final int pos;
 
@@ -81,8 +83,7 @@ class GSS {
         private void newNode2(Node p, Node parent, Forest pending, Parser.Table.State state, boolean fromEmptyReduction, Phase start) {
             p.holder.merge(pending);
             if (p.parents().contains(parent)) return;
-            p.parents().add(parent, true);
-            if (p!=parent && !fromEmptyReduction) p.queueReductions(parent);
+            p.addParent(parent, fromEmptyReduction);
         }
         private void newNode3(Node parent, Forest pending, Parser.Table.State state, boolean fromEmptyReduction, Phase start) {
             do {
@@ -91,8 +92,7 @@ class GSS {
                 if (token==null) break;
                 int count = 0;
                 Parser.Table.Reduction r = null;
-                for(Parser.Table.Reduction red : token==null ? state.getEofReductions() : state.getReductions(token)) { r = red; count++; }
-                if (count==0) return;     // BEWARE! this optimization is suspected to cause really nasty heisenbugs
+                if (!state.hasReductions(token)) return;
                 //if (count > 1) break;
                 //if (r.numPop == 0) break;
                 //r.reduce(pending, parent, null, Phase.this, null);
@@ -105,7 +105,6 @@ class GSS {
         }
 
         
-        boolean reducing = false;
         /** perform all reduction operations */
         public void reduce() {
             reducing = true;
@@ -116,8 +115,12 @@ class GSS {
             int num = hv.size();
             for(int i=0; i<num; i++) {
                 Node n = reducing_list[i];
-                reducing_list[i] = null;
                 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();
             }
         }
@@ -154,13 +157,13 @@ class GSS {
                 //n.queueEmptyReductions();
                 //}
                 //error.append("  after: " +pendingReductions+ "\n");
-                error.append("  candidate states:\n");
-                for(Phase.Node n : hash.values()) {
+                //error.append("  candidate states:\n");
+                //for(Phase.Node n : hash.values()) {
                     //for(Sequence.Position p : n.state) error.append("        " + p + "\n");
                     //error.append("        --\n");
-                    for(Parser.Table.Reduction r : n.state.getReductions(token)) error.append("        " + r + "\n");
+                //for(Parser.Table.Reduction r : n.state.getReductions(token)) error.append("        " + r + "\n");
                     //error.append("        ==\n");
-                }
+                //}
                 next.error = error.toString();
             }
 
@@ -174,81 +177,52 @@ class GSS {
         /** a node in the GSS */
         public final class Node extends FastSet<Node> {
 
+            public void addParent(Node parent, boolean fromEmptyReduction) {
+                parents().add(parent, true);
+                if (this!=parent && !fromEmptyReduction) queueReductions(parent);
+            }
+
             private Forest.Ref holder = null;
             private boolean allqueued = false;
 
-            private HashMap<Parser.Table.Reduction,Forest> cache = null;
-
-            /** the set of nodes to which there is an edge starting at this node */
-            //public final FastSet<Node> parents = new FastSet<Node>();  /* ALLOC */
-
             /** what state this node is in */
             public final Parser.Table.State state;
 
             /** which Phase this Node belongs to (node that Node is also a non-static inner class of Phase) */
-            public final Phase phase = Phase.this;
+            public Phase phase() { return Phase.this; }
 
-            public  HashMap<Parser.Table.Reduction,Forest> cache() {
-                return cache==null ? (cache = new HashMap<Parser.Table.Reduction,Forest>()) : cache; }
             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; }
 
-            /** FIXME */
             public void queueReductions() {
                 if (allqueued) return;
                 allqueued = true;
                 int where = parents().size();
-                for(int i=0; i<where; i++) queueReductions(get(i));
+                for(Parser.Table.Reduction r : state.getReductions(token))
+                    if (r.numPop >= 1)
+                        r.reduce(this);
             }
 
-            /** FIXME */
             public void queueReductions(Node n2) {
                 if (!allqueued) { queueReductions(); return; }
-                Node n = this;
-                for(Parser.Table.Reduction r : token==null ? n.state.getEofReductions() : n.state.getReductions(token)) {
-                    
-                    // UGLY HACK
-                    // The problem here is that a "reduction of length 1"
-                    // performed twice with different values of n2 needs
-                    // to only create a *single* new result, but must add
-                    // multiple parents to the node holding that result.
-                    // The current reducer doesn't differentiate between
-                    // the next node of an n-pop reduction and the
-                    // ultimate parent of the last pop, so we need to
-                    // cache instances here as a way of avoiding
-                    // recreating them.
-                    
-                    // currently we have this weird problem where we
-                    // have to do an individual reduct for each child
-                    // when the reduction length is one (ie the
-                    // children wind up being children of the newly
-                    // created node rather than part of the popped
-                    // sequence
-                    if (r.numPop <= 0) continue;
-                    if (r.numPop == 1) {
-                        Forest ret = n.cache().get(r);
-                        if (ret != null) r.reduce(n, n2, n.phase, ret);
-                        else n.cache().put(r, r.reduce(n, n2, n.phase, null));
-                    } else {
-                        r.reduce(n, n2, Phase.this, null);
-                    }
-                }
+                for(Parser.Table.Reduction r : state.getReductions(token))
+                    if (r.numPop > 0)
+                        r.reduce(this, n2);
             }
 
 
-            /** FIXME */
             public void queueEmptyReductions() {
                 if (reducing)
                     for(Parser.Table.Reduction r : token==null ? state.getEofReductions() : state.getReductions(token))
                         if (r.numPop==0)
-                            r.reduce(this, null, this.phase, r.zero());
+                            r.reduce(this);
             }
 
             private Node(Node parent, Forest pending, Parser.Table.State state, Phase start) {
                 this.state = state;
                 if (pending != null) this.holder().merge(pending);
-                if (parent != null) parents().add(parent, true);
+                if (parent != null) parents().add(parent);
                 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++;
@@ -269,5 +243,4 @@ class GSS {
     private static long code(Parser.Table.State state, Phase start) {
         return (((long)state.idx) << 32) | (start==null ? 0 : start.pos);
     }
-    public boolean yak = false;
 }