checkpoint

[sbp.git] / src / edu / berkeley / sbp / GSS.java

diff --git a/src/edu/berkeley/sbp/GSS.java b/src/edu/berkeley/sbp/GSS.java
index dcc8f33..26b6448 100644 (file)
--- a/src/edu/berkeley/sbp/GSS.java
+++ b/src/edu/berkeley/sbp/GSS.java
@@ -115,14 +115,15 @@ class GSS {
             if (!fromEmptyReduction) n.queueReductions();
         }
 
+        
+        boolean reducing = false;
         /** perform all reduction operations */
         public void reduce() {
+            reducing = true;
             HashSet<Phase.Node> s = new HashSet<Phase.Node>();
             s.addAll(hash.values());
-            for(Phase.Node n : s) {
-                n.queueEmptyReductions();
-                n.queueReductions();
-            }
+            for(Phase.Node n : s) n.queueEmptyReductions();
+            for(Phase.Node n : s) n.queueReductions();
             while(pendingReduct.size()>0)
                 //pendingReduct.iterator().next().go();
                 pendingReduct.removeFirst().go();
@@ -134,6 +135,7 @@ class GSS {
             Forest res = null;
             boolean ok = false;
             for(Phase.Node n : hash.values()) {
+                if (n.holder==null) continue;
                 n.holder.resolve();
                 if (token == null && n.state.isAccepting()) {
                     ok = true;
@@ -154,10 +156,10 @@ class GSS {
                 error.append("error: unable to shift token \"" + token + "\"\n");
                 error.append("  before: " +pendingReductions+ "\n");
                 error.append("  before: " +totalReductions+ "\n");
-                for(Phase.Node n : hash.values()) {
-                    n.queueReductions();
-                    n.queueEmptyReductions();
-                }
+                //for(Phase.Node n : hash.values()) {
+                //n.queueReductions();
+                //n.queueEmptyReductions();
+                //}
                 error.append("  after: " +pendingReductions+ "\n");
                 error.append("  candidate states:\n");
                 for(Phase.Node n : hash.values()) {
@@ -213,10 +215,10 @@ class GSS {
 
             /** FIXME */
             public void queueEmptyReductions() {
-                for(Parser.Table.Reduction r : token==null ? state.getEofReductions() : state.getReductions(token)) {
-                    if (r.numPop==0)
-                        newReduct(this, null, r);   /* ALLOC */
-                }
+                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());
             }
 
             private Node(Node parent, Forest pending, Parser.Table.State state, Phase start) {
@@ -263,6 +265,7 @@ class GSS {
                 reductions.add(this);
                 pendingReduct.addFirst(this);
                 pendingReductions++;
+                //if (reducing) go();
             }
 
             /** perform the reduction */
@@ -272,9 +275,20 @@ class GSS {
                 pendingReduct.remove(this);
                 pendingReductions--;
 
-                if (r==null)
+                if (r==null) {
                     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
@@ -282,34 +296,17 @@ class GSS {
                         // created node rather than part of the popped
                         // sequence
                         
-                        if (r.numPop == 1) new Reduct(n, n2, r).go();
+                        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));
+                        }
                     }
-
-
-                // FIXME: explain this
-                if (r==null) {
                     for(Parser.Table.Reduction r : token==null ? n.state.getEofReductions() : n.state.getReductions(token)) {
                         if (r.numPop <= 1) continue;
                         r.reduce(n, n2, Phase.this, null);
                     }
-                } else if (r.numPop==0) { r.reduce(n, n2, n.phase, r.zero());
-                } else if (r.numPop==1) {
-                    // UGLY HACK
-                    // The problem here is that a "reduction of length 0/1"
-                    // 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.
-                    
-                    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 {
+                } else if (r.numPop != 1) {
                     r.reduce(n, n2, Phase.this, null);
                 }
             }
@@ -338,5 +335,5 @@ 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;
 }