checkpoint

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

diff --git a/src/edu/berkeley/sbp/Parser.java b/src/edu/berkeley/sbp/Parser.java
index 58d0bc2..08c49a9 100644 (file)
--- a/src/edu/berkeley/sbp/Parser.java
+++ b/src/edu/berkeley/sbp/Parser.java
@@ -134,7 +134,7 @@ public abstract class Parser<T extends Token, R> {
                         Walk.Follow wf = new Walk.Follow(top.empty(), p.owner(), all_elements, cache);
                         Reduction red = new Reduction(p);
                         state.reductions.put(wf.walk(p.owner()), red);
-                        if (wf.includesEof()) state.eofReductions.add(red, true);
+                        if (wf.includesEof()) state.eofReductions.add(red);
                     }
 
                     // if the element following this position is an atom, copy the corresponding
@@ -168,14 +168,14 @@ public abstract class Parser<T extends Token, R> {
             }
             */
 
-            public final      int               idx    = master_state_idx++;
+            public  final     int               idx    = master_state_idx++;
             private final     HashSet<Position> hs;
 
             private transient HashMap<Element,State>          gotoSetNonTerminals = new HashMap<Element,State>();
             private transient TopologicalBag<Token,State>     gotoSetTerminals    = new TopologicalBag<Token,State>();
 
             private           TopologicalBag<Token,Reduction> reductions          = new TopologicalBag<Token,Reduction>();
-            private           FastSet<Reduction>              eofReductions       = new FastSet<Reduction>();
+            private           HashSet<Reduction>              eofReductions       = new HashSet<Reduction>();
             private           TopologicalBag<Token,State>     shifts              = new TopologicalBag<Token,State>();
             private           boolean                         accept              = false;
 
@@ -184,7 +184,7 @@ public abstract class Parser<T extends Token, R> {
             public boolean             canShift(Token t)           { return shifts.contains(t); }
             public Iterable<State>     getShifts(Token t)          { return shifts.get(t); }
             public boolean             isAccepting()               { return accept; }
-            public Iterable<Reduction> getReductions(Token t)      { return reductions.get(t); }
+            public Iterable<Reduction> getReductions(Token t)      { return t==null ? eofReductions : reductions.get(t); }
             public Iterable<Reduction> getEofReductions()          { return eofReductions; }
             public Iterator<Position>  iterator()                  { return hs.iterator(); }
 
@@ -310,13 +310,6 @@ public abstract class Parser<T extends Token, R> {
                 this.holder = new Forest[numPop];
             }
             public String toString() { return "[reduce " + position + "]"; }
-            public Forest reduce(Forest f, GSS.Phase.Node parent, GSS.Phase.Node onlychild, GSS.Phase target, Forest rex) {
-                holder[numPop-1] = f;
-                return reduce(parent, numPop-2, rex, onlychild, target);                
-            }
-            public Forest reduce(GSS.Phase.Node parent, GSS.Phase.Node onlychild, GSS.Phase target, Forest rex) {
-                return reduce(parent, numPop-1, rex, onlychild, target);
-            }
 
             private Forest zero = null;
             public Forest zero() {
@@ -325,26 +318,41 @@ public abstract class Parser<T extends Token, R> {
                 return zero = position.rewrite(null);
             }
 
+            public Forest reduce(GSS.Phase.Node parent) {
+                if (numPop==0) return finish(parent, zero(), parent.phase());
+                return reduce(parent, numPop-1, null, parent.phase());
+            }
+
+            public Forest reduce(GSS.Phase.Node parent, GSS.Phase.Node onlychild) {
+                if (numPop<=0) throw new Error("called wrong form of reduce()");
+                int pos = numPop-1;
+                holder[pos] = parent.pending();
+                if (pos==0) {
+                    System.arraycopy(holder, 0, position.holder, 0, holder.length);
+                    return finish(onlychild, position.rewrite(parent.phase().getLocation()), parent.phase());
+                }
+                return reduce(onlychild, pos-1, null, parent.phase());
+            }
+
             // FIXME: this could be more elegant and/or cleaner and/or somewhere else
-            private Forest reduce(GSS.Phase.Node parent, int pos, Forest rex, GSS.Phase.Node onlychild, GSS.Phase target) {
-                if (pos>=0) holder[pos] = parent.pending();
-                if (pos<=0 && rex==null) {
+            private Forest reduce(GSS.Phase.Node parent, int pos, Forest rex, GSS.Phase target) {
+                if (pos<0) return finish(parent, rex, target);
+                holder[pos] = parent.pending();
+                if (pos==0 && rex==null) {
                     System.arraycopy(holder, 0, position.holder, 0, holder.length);
                     rex = position.rewrite(target.getLocation());
                 }
-                if (pos >=0) {
-                    if (onlychild != null)
-                        reduce(onlychild, pos-1, rex, null, target);
-                    else 
-                        for(GSS.Phase.Node child : parent.parents())
-                            reduce(child, pos-1, rex, null, target);
-                } else {
-                    State state = parent.state.gotoSetNonTerminals.get(position.owner());
-                    if (state!=null)
-                        target.newNode(parent, rex, state, numPop<=0, parent.phase);
-                }
+                for(GSS.Phase.Node child : parent.parents())
+                    if (pos==0) finish(child, rex, target);
+                    else reduce(child, pos-1, rex, target);
                 return rex;
             }
+            private Forest finish(GSS.Phase.Node parent, Forest result, GSS.Phase target) {
+                State state = parent.state.gotoSetNonTerminals.get(position.owner());
+                if (state!=null)
+                    target.newNode(parent, result, state, numPop<=0, parent.phase());
+                return result;
+            }
         }
     }