- System.arraycopy(holder, 0, r.position.holder, 0, holder.length);
- for(int i=0; i<r.position.pos; i++) if (r.position.holder[i]==null) throw new Error("realbad");
- Forest rex = r.position.rewrite(target.getLocation());
- for(GSS.Phase.Node child : this.parents()) child.finish(r, rex, target, holder);
+ 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");
+ Forest rex = null;
+ if (r.pos==1) rex = singularReductions.get(this, r);
+ if (rex==null) {
+ rex = r.rewrite(phase().getLocation());
+ if (r.pos==1) singularReductions.put(this, r, rex);
+ }
+ for(Node child : this.parents()) child.finish(r, rex, target, holder);