private static void linkChildren(RArray parentRealView, ViewTrace parentTrace) {
   Class viewClass = parentRealView.getClass();
   Field[] fields = getAllFields(viewClass);
   for (Field f : fields) {
     if (f.isSynthetic()) {
       continue;
     }
     Class fieldClass = f.getType();
     if (RArray.class.isAssignableFrom(fieldClass)) {
       try {
         f.setAccessible(true);
         Object o = f.get(parentRealView);
         if (o instanceof TracingView) {
           ((TracingView) o).getTrace().parentView = parentTrace;
         }
       } catch (IllegalAccessException e) {
         assert Utils.check(false, "can't read a view field " + e);
       }
     }
   }
 }
    private static void extractViewPattern(int depth, ViewTrace trace, StringBuilder p) {
      if (!processedViewsForPatterns.add(trace)) {
        p.append("(ALIASED) ");
      }

      p.append(trace.realView.getClass() + " size = " + trace.realView.size() + "\n");
      indent(depth, p);

      p.append("    use:");
      if (trace.materializeCount == 0 && trace.sumCount == 0 && trace.getCount == 0) {
        p.append(" UNUSED");
      } else {
        if (trace.getCount > 0) {
          p.append(" get");
        }
        if (trace.materializeCount > 0) {
          p.append(" materialize");
        }
        if (trace.sumCount > 0) {
          p.append(" sum");
        }
      }
      p.append("\n");

      if (false) {
        p.append("    allocationSite =");
        Site.printSite(trace.allocationSite, p);
        p.append("\n");
        indent(depth, p);
      }

      RArray view = trace.realView;
      Class viewClass = view.getClass();
      Field[] fields = getAllFields(viewClass);
      boolean printedField = false;

      for (Field f : fields) {
        if (f.isSynthetic()) {
          continue;
        }
        Class fieldClass = f.getType();
        if (RArray.class.isAssignableFrom(fieldClass)) {
          continue; // these later
        }
        indent(depth, p);
        p.append("    " + f.getName() + " ");
        try {
          f.setAccessible(true);
          Object o = f.get(view);
          p.append(o == null ? "null (" + fieldClass + ")" : o.getClass());
          p.append("\n");
          printedField = true;
        } catch (IllegalAccessException e) {
          assert Utils.check(false, "can't read a view field " + e);
        }
      }

      boolean printNewline = printedField;
      for (Field f : fields) {
        if (f.isSynthetic()) {
          continue;
        }
        Class fieldClass = f.getType();
        if (!RArray.class.isAssignableFrom(fieldClass)) {
          continue;
        }
        if (printNewline) {
          p.append("\n");
          printNewline = false;
        }
        indent(depth, p);
        p.append("    " + f.getName() + " ");
        try {
          f.setAccessible(true);
          Object o = f.get(view);
          if (o instanceof TracingView) {
            p.append("VIEW ");
            TracingView child = (TracingView) o;
            extractViewPattern(depth + 2, child.getTrace(), p);
          } else {
            p.append("ARRAY " + o.getClass() + " size = " + ((RArray) o).size());
            if (o instanceof View) {
              ps.println("MISSED VIEW " + o);
            }
          }
          p.append("\n");
        } catch (IllegalAccessException e) {
          assert Utils.check(false, "can't read a view field " + e);
        }
      }
    }
    private static void dumpView(int depth, ViewTrace trace) {
      printedIndividualViews.add(trace);

      ps.println(trace.realView + " size = " + trace.realView.size());
      if (TRACE_ALLOCATION_SITE) {
        indent(depth);
        ps.print("    allocationSite =");
        Site.printSite(trace.allocationSite);
        ps.println();
      }

      int unused = trace.unusedElements();
      int redundant = trace.redundantGets();

      boolean singleUse;
      Site[] useSites;

      if (TRACE_USE_SITES) {
        useSites = trace.useSites.toArray(new Site[trace.useSites.size()]);
        singleUse = (useSites.length == 1);
      } else if (TRACE_SINGLE_USE_SITE) {
        useSites = null;
        singleUse = !trace.multipleUseSites;
      } else {
        useSites = null;
        singleUse = false;
      }
      if (singleUse) {
        indent(depth);
        ps.print("    singleUseSite = US");
        Site.printSite(useSites != null ? useSites[0] : trace.singleUseSite);

        if (trace.getCount > 0) {
          ps.println(" (get)");
        } else if (trace.sumCount > 0) {
          ps.println(" (sum)");
        } else {
          ps.println(" (materialize)");
        }

      } else if (trace.getCount > 0) {
        if (TRACE_FIRST_GET_SITE) {
          indent(depth);
          ps.print("    firstGetSite =");
          Site.printSite(trace.firstGetSite);
          ps.println();
        }
        if (trace.materializeCount == 0 && trace.sumCount == 0) {
          if (unused > 0) {
            indent(depth);
            ps.println("    unusedElements = " + unused);
          }
          if (redundant > 0) {
            indent(depth);
            ps.println("    redundantGets = " + redundant + " (no materialize, sum)");
          }
        }
      } else {
        if (trace.materializeCount == 0 && trace.sumCount == 0) {
          indent(depth);
          ps.println("    UNUSED");
        } else {
          indent(depth);
          ps.println(
              "    materializeCount = "
                  + trace.materializeCount
                  + " sumCount = "
                  + trace.sumCount
                  + " getCount = "
                  + trace.getCount);
        }
      }
      if (TRACE_FIRST_MATERIALIZE_SITE && trace.materializeCount > 0 && !singleUse) {
        indent(depth);
        ps.print("    firstMaterializeSite =");
        Site.printSite(trace.firstMaterializeSite);
        ps.println();
      }
      if (TRACE_FIRST_SUM_SITE && trace.sumCount > 0 && !singleUse) {
        indent(depth);
        ps.print("    firstSumSite =");
        Site.printSite(trace.firstSumSite);
        ps.println();
      }
      if (TRACE_USE_SITES) {
        if (useSites.length != 1) {
          indent(depth);
          ps.println("    useSites (" + useSites.length + "):");
          for (Site s : useSites) {
            indent(depth);
            ps.print("        US");
            Site.printSite(s);
            ps.println();
          }
        }
      }

      ps.println();
      RArray view = trace.realView;
      Class viewClass = view.getClass();
      Field[] fields = getAllFields(viewClass);
      boolean printedField = false;

      for (Field f : fields) {
        if (f.isSynthetic()) {
          continue;
        }
        Class fieldClass = f.getType();
        if (RArray.class.isAssignableFrom(fieldClass)) {
          continue; // these later
        }
        indent(depth);
        ps.print("    " + f.getName() + " ");
        try {
          f.setAccessible(true);
          ps.println(f.get(view));
          printedField = true;
        } catch (IllegalAccessException e) {
          assert Utils.check(false, "can't read a view field " + e);
        }
      }

      boolean printNewline = printedField;
      for (Field f : fields) {
        if (f.isSynthetic()) {
          continue;
        }
        Class fieldClass = f.getType();
        if (!RArray.class.isAssignableFrom(fieldClass)) {
          continue;
        }
        if (printNewline) {
          ps.println();
          printNewline = false;
        }
        indent(depth);
        ps.print("    " + f.getName() + " ");
        try {
          f.setAccessible(true);
          Object o = f.get(view);
          if (o instanceof TracingView) {
            ps.print("VIEW ");
            TracingView child = (TracingView) o;
            dumpView(depth + 2, child.getTrace());
          } else {
            ps.print("ARRAY " + o + " size = " + ((RArray) o).size());
            if (o instanceof View) {
              ps.println("MISSED VIEW " + o);
            }
          }
          ps.println();
        } catch (IllegalAccessException e) {
          assert Utils.check(false, "can't read a view field " + e);
        }
      }
    }