diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/hotspot/share/memory/heapInspection.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/memory/heapInspection.cpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,784 @@
+/*
+ * Copyright (c) 2002, 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "classfile/classLoaderData.hpp"
+#include "classfile/moduleEntry.hpp"
+#include "classfile/systemDictionary.hpp"
+#include "gc/shared/collectedHeap.hpp"
+#include "gc/shared/genCollectedHeap.hpp"
+#include "memory/heapInspection.hpp"
+#include "memory/resourceArea.hpp"
+#include "oops/oop.inline.hpp"
+#include "runtime/os.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/macros.hpp"
+#include "utilities/stack.inline.hpp"
+#if INCLUDE_ALL_GCS
+#include "gc/parallel/parallelScavengeHeap.hpp"
+#endif // INCLUDE_ALL_GCS
+
+// HeapInspection
+
+int KlassSizeStats::count(oop x) {
+  return (HeapWordSize * (((x) != NULL) ? (x)->size() : 0));
+}
+
+int KlassSizeStats::count_array(objArrayOop x) {
+  return (HeapWordSize * (((x) != NULL) ? (x)->size() : 0));
+}
+
+inline KlassInfoEntry::~KlassInfoEntry() {
+  if (_subclasses != NULL) {
+    delete _subclasses;
+  }
+}
+
+inline void KlassInfoEntry::add_subclass(KlassInfoEntry* cie) {
+  if (_subclasses == NULL) {
+    _subclasses = new  (ResourceObj::C_HEAP, mtInternal) GrowableArray<KlassInfoEntry*>(4, true);
+  }
+  _subclasses->append(cie);
+}
+
+int KlassInfoEntry::compare(KlassInfoEntry* e1, KlassInfoEntry* e2) {
+  if(e1->_instance_words > e2->_instance_words) {
+    return -1;
+  } else if(e1->_instance_words < e2->_instance_words) {
+    return 1;
+  }
+  // Sort alphabetically, note 'Z' < '[' < 'a', but it's better to group
+  // the array classes before all the instance classes.
+  ResourceMark rm;
+  const char* name1 = e1->klass()->external_name();
+  const char* name2 = e2->klass()->external_name();
+  bool d1 = (name1[0] == '[');
+  bool d2 = (name2[0] == '[');
+  if (d1 && !d2) {
+    return -1;
+  } else if (d2 && !d1) {
+    return 1;
+  } else {
+    return strcmp(name1, name2);
+  }
+}
+
+const char* KlassInfoEntry::name() const {
+  const char* name;
+  if (_klass->name() != NULL) {
+    name = _klass->external_name();
+  } else {
+    if (_klass == Universe::boolArrayKlassObj())         name = "<boolArrayKlass>";         else
+    if (_klass == Universe::charArrayKlassObj())         name = "<charArrayKlass>";         else
+    if (_klass == Universe::singleArrayKlassObj())       name = "<singleArrayKlass>";       else
+    if (_klass == Universe::doubleArrayKlassObj())       name = "<doubleArrayKlass>";       else
+    if (_klass == Universe::byteArrayKlassObj())         name = "<byteArrayKlass>";         else
+    if (_klass == Universe::shortArrayKlassObj())        name = "<shortArrayKlass>";        else
+    if (_klass == Universe::intArrayKlassObj())          name = "<intArrayKlass>";          else
+    if (_klass == Universe::longArrayKlassObj())         name = "<longArrayKlass>";         else
+      name = "<no name>";
+  }
+  return name;
+}
+
+void KlassInfoEntry::print_on(outputStream* st) const {
+  ResourceMark rm;
+
+  // simplify the formatting (ILP32 vs LP64) - always cast the numbers to 64-bit
+  ModuleEntry* module = _klass->module();
+  if (module->is_named()) {
+    st->print_cr(INT64_FORMAT_W(13) "  " UINT64_FORMAT_W(13) "  %s (%s@%s)",
+                 (int64_t)_instance_count,
+                 (uint64_t)_instance_words * HeapWordSize,
+                 name(),
+                 module->name()->as_C_string(),
+                 module->version() != NULL ? module->version()->as_C_string() : "");
+  } else {
+    st->print_cr(INT64_FORMAT_W(13) "  " UINT64_FORMAT_W(13) "  %s",
+                 (int64_t)_instance_count,
+                 (uint64_t)_instance_words * HeapWordSize,
+                 name());
+  }
+}
+
+KlassInfoEntry* KlassInfoBucket::lookup(Klass* const k) {
+  KlassInfoEntry* elt = _list;
+  while (elt != NULL) {
+    if (elt->is_equal(k)) {
+      return elt;
+    }
+    elt = elt->next();
+  }
+  elt = new (std::nothrow) KlassInfoEntry(k, list());
+  // We may be out of space to allocate the new entry.
+  if (elt != NULL) {
+    set_list(elt);
+  }
+  return elt;
+}
+
+void KlassInfoBucket::iterate(KlassInfoClosure* cic) {
+  KlassInfoEntry* elt = _list;
+  while (elt != NULL) {
+    cic->do_cinfo(elt);
+    elt = elt->next();
+  }
+}
+
+void KlassInfoBucket::empty() {
+  KlassInfoEntry* elt = _list;
+  _list = NULL;
+  while (elt != NULL) {
+    KlassInfoEntry* next = elt->next();
+    delete elt;
+    elt = next;
+  }
+}
+
+void KlassInfoTable::AllClassesFinder::do_klass(Klass* k) {
+  // This has the SIDE EFFECT of creating a KlassInfoEntry
+  // for <k>, if one doesn't exist yet.
+  _table->lookup(k);
+}
+
+KlassInfoTable::KlassInfoTable(bool add_all_classes) {
+  _size_of_instances_in_words = 0;
+  _size = 0;
+  _ref = (HeapWord*) Universe::boolArrayKlassObj();
+  _buckets =
+    (KlassInfoBucket*)  AllocateHeap(sizeof(KlassInfoBucket) * _num_buckets,
+       mtInternal, CURRENT_PC, AllocFailStrategy::RETURN_NULL);
+  if (_buckets != NULL) {
+    _size = _num_buckets;
+    for (int index = 0; index < _size; index++) {
+      _buckets[index].initialize();
+    }
+    if (add_all_classes) {
+      AllClassesFinder finder(this);
+      ClassLoaderDataGraph::classes_do(&finder);
+    }
+  }
+}
+
+KlassInfoTable::~KlassInfoTable() {
+  if (_buckets != NULL) {
+    for (int index = 0; index < _size; index++) {
+      _buckets[index].empty();
+    }
+    FREE_C_HEAP_ARRAY(KlassInfoBucket, _buckets);
+    _size = 0;
+  }
+}
+
+uint KlassInfoTable::hash(const Klass* p) {
+  return (uint)(((uintptr_t)p - (uintptr_t)_ref) >> 2);
+}
+
+KlassInfoEntry* KlassInfoTable::lookup(Klass* k) {
+  uint         idx = hash(k) % _size;
+  assert(_buckets != NULL, "Allocation failure should have been caught");
+  KlassInfoEntry*  e   = _buckets[idx].lookup(k);
+  // Lookup may fail if this is a new klass for which we
+  // could not allocate space for an new entry.
+  assert(e == NULL || k == e->klass(), "must be equal");
+  return e;
+}
+
+// Return false if the entry could not be recorded on account
+// of running out of space required to create a new entry.
+bool KlassInfoTable::record_instance(const oop obj) {
+  Klass*        k = obj->klass();
+  KlassInfoEntry* elt = lookup(k);
+  // elt may be NULL if it's a new klass for which we
+  // could not allocate space for a new entry in the hashtable.
+  if (elt != NULL) {
+    elt->set_count(elt->count() + 1);
+    elt->set_words(elt->words() + obj->size());
+    _size_of_instances_in_words += obj->size();
+    return true;
+  } else {
+    return false;
+  }
+}
+
+void KlassInfoTable::iterate(KlassInfoClosure* cic) {
+  assert(_size == 0 || _buckets != NULL, "Allocation failure should have been caught");
+  for (int index = 0; index < _size; index++) {
+    _buckets[index].iterate(cic);
+  }
+}
+
+size_t KlassInfoTable::size_of_instances_in_words() const {
+  return _size_of_instances_in_words;
+}
+
+int KlassInfoHisto::sort_helper(KlassInfoEntry** e1, KlassInfoEntry** e2) {
+  return (*e1)->compare(*e1,*e2);
+}
+
+KlassInfoHisto::KlassInfoHisto(KlassInfoTable* cit) :
+  _cit(cit) {
+  _elements = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<KlassInfoEntry*>(_histo_initial_size, true);
+}
+
+KlassInfoHisto::~KlassInfoHisto() {
+  delete _elements;
+}
+
+void KlassInfoHisto::add(KlassInfoEntry* cie) {
+  elements()->append(cie);
+}
+
+void KlassInfoHisto::sort() {
+  elements()->sort(KlassInfoHisto::sort_helper);
+}
+
+void KlassInfoHisto::print_elements(outputStream* st) const {
+  // simplify the formatting (ILP32 vs LP64) - store the sum in 64-bit
+  int64_t total = 0;
+  uint64_t totalw = 0;
+  for(int i=0; i < elements()->length(); i++) {
+    st->print("%4d: ", i+1);
+    elements()->at(i)->print_on(st);
+    total += elements()->at(i)->count();
+    totalw += elements()->at(i)->words();
+  }
+  st->print_cr("Total " INT64_FORMAT_W(13) "  " UINT64_FORMAT_W(13),
+               total, totalw * HeapWordSize);
+}
+
+#define MAKE_COL_NAME(field, name, help)     #name,
+#define MAKE_COL_HELP(field, name, help)     help,
+
+static const char *name_table[] = {
+  HEAP_INSPECTION_COLUMNS_DO(MAKE_COL_NAME)
+};
+
+static const char *help_table[] = {
+  HEAP_INSPECTION_COLUMNS_DO(MAKE_COL_HELP)
+};
+
+bool KlassInfoHisto::is_selected(const char *col_name) {
+  if (_selected_columns == NULL) {
+    return true;
+  }
+  if (strcmp(_selected_columns, col_name) == 0) {
+    return true;
+  }
+
+  const char *start = strstr(_selected_columns, col_name);
+  if (start == NULL) {
+    return false;
+  }
+
+  // The following must be true, because _selected_columns != col_name
+  if (start > _selected_columns && start[-1] != ',') {
+    return false;
+  }
+  char x = start[strlen(col_name)];
+  if (x != ',' && x != '\0') {
+    return false;
+  }
+
+  return true;
+}
+
+void KlassInfoHisto::print_title(outputStream* st, bool csv_format,
+                                 bool selected[], int width_table[],
+                                 const char *name_table[]) {
+  if (csv_format) {
+    st->print("Index,Super");
+    for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+       if (selected[c]) {st->print(",%s", name_table[c]);}
+    }
+    st->print(",ClassName");
+  } else {
+    st->print("Index Super");
+    for (int c = 0; c < KlassSizeStats::_num_columns; c++) {
+      if (selected[c]) {
+        st->print("%*s", width_table[c], name_table[c]);
+      }
+    }
+    st->print(" ClassName");
+  }
+
+  if (is_selected("ClassLoader")) {
+    st->print(",ClassLoader");
+  }
+  st->cr();
+}
+
+class HierarchyClosure : public KlassInfoClosure {
+private:
+  GrowableArray<KlassInfoEntry*> *_elements;
+public:
+  HierarchyClosure(GrowableArray<KlassInfoEntry*> *_elements) : _elements(_elements) {}
+
+  void do_cinfo(KlassInfoEntry* cie) {
+    // ignore array classes
+    if (cie->klass()->is_instance_klass()) {
+      _elements->append(cie);
+    }
+  }
+};
+
+void KlassHierarchy::print_class_hierarchy(outputStream* st, bool print_interfaces,
+                                           bool print_subclasses, char* classname) {
+  ResourceMark rm;
+  Stack <KlassInfoEntry*, mtClass> class_stack;
+  GrowableArray<KlassInfoEntry*> elements;
+
+  // Add all classes to the KlassInfoTable, which allows for quick lookup.
+  // A KlassInfoEntry will be created for each class.
+  KlassInfoTable cit(true);
+  if (cit.allocation_failed()) {
+    st->print_cr("ERROR: Ran out of C-heap; hierarchy not generated");
+    return;
+  }
+
+  // Add all created KlassInfoEntry instances to the elements array for easy
+  // iteration, and to allow each KlassInfoEntry instance to have a unique index.
+  HierarchyClosure hc(&elements);
+  cit.iterate(&hc);
+
+  for(int i = 0; i < elements.length(); i++) {
+    KlassInfoEntry* cie = elements.at(i);
+    Klass* super = cie->klass()->super();
+
+    // Set the index for the class.
+    cie->set_index(i + 1);
+
+    // Add the class to the subclass array of its superclass.
+    if (super != NULL) {
+      KlassInfoEntry* super_cie = cit.lookup(super);
+      assert(super_cie != NULL, "could not lookup superclass");
+      super_cie->add_subclass(cie);
+    }
+  }
+
+  // Set the do_print flag for each class that should be printed.
+  for(int i = 0; i < elements.length(); i++) {
+    KlassInfoEntry* cie = elements.at(i);
+    if (classname == NULL) {
+      // We are printing all classes.
+      cie->set_do_print(true);
+    } else {
+      // We are only printing the hierarchy of a specific class.
+      if (strcmp(classname, cie->klass()->external_name()) == 0) {
+        KlassHierarchy::set_do_print_for_class_hierarchy(cie, &cit, print_subclasses);
+      }
+    }
+  }
+
+  // Now we do a depth first traversal of the class hierachry. The class_stack will
+  // maintain the list of classes we still need to process. Start things off
+  // by priming it with java.lang.Object.
+  KlassInfoEntry* jlo_cie = cit.lookup(SystemDictionary::Object_klass());
+  assert(jlo_cie != NULL, "could not lookup java.lang.Object");
+  class_stack.push(jlo_cie);
+
+  // Repeatedly pop the top item off the stack, print its class info,
+  // and push all of its subclasses on to the stack. Do this until there
+  // are no classes left on the stack.
+  while (!class_stack.is_empty()) {
+    KlassInfoEntry* curr_cie = class_stack.pop();
+    if (curr_cie->do_print()) {
+      print_class(st, curr_cie, print_interfaces);
+      if (curr_cie->subclasses() != NULL) {
+        // Current class has subclasses, so push all of them onto the stack.
+        for (int i = 0; i < curr_cie->subclasses()->length(); i++) {
+          KlassInfoEntry* cie = curr_cie->subclasses()->at(i);
+          if (cie->do_print()) {
+            class_stack.push(cie);
+          }
+        }
+      }
+    }
+  }
+
+  st->flush();
+}
+
+// Sets the do_print flag for every superclass and subclass of the specified class.
+void KlassHierarchy::set_do_print_for_class_hierarchy(KlassInfoEntry* cie, KlassInfoTable* cit,
+                                                      bool print_subclasses) {
+  // Set do_print for all superclasses of this class.
+  Klass* super = ((InstanceKlass*)cie->klass())->java_super();
+  while (super != NULL) {
+    KlassInfoEntry* super_cie = cit->lookup(super);
+    super_cie->set_do_print(true);
+    super = super->super();
+  }
+
+  // Set do_print for this class and all of its subclasses.
+  Stack <KlassInfoEntry*, mtClass> class_stack;
+  class_stack.push(cie);
+  while (!class_stack.is_empty()) {
+    KlassInfoEntry* curr_cie = class_stack.pop();
+    curr_cie->set_do_print(true);
+    if (print_subclasses && curr_cie->subclasses() != NULL) {
+      // Current class has subclasses, so push all of them onto the stack.
+      for (int i = 0; i < curr_cie->subclasses()->length(); i++) {
+        KlassInfoEntry* cie = curr_cie->subclasses()->at(i);
+        class_stack.push(cie);
+      }
+    }
+  }
+}
+
+static void print_indent(outputStream* st, int indent) {
+  while (indent != 0) {
+    st->print("|");
+    indent--;
+    if (indent != 0) {
+      st->print("  ");
+    }
+  }
+}
+
+// Print the class name and its unique ClassLoader identifer.
+static void print_classname(outputStream* st, Klass* klass) {
+  oop loader_oop = klass->class_loader_data()->class_loader();
+  st->print("%s/", klass->external_name());
+  if (loader_oop == NULL) {
+    st->print("null");
+  } else {
+    st->print(INTPTR_FORMAT, p2i(klass->class_loader_data()));
+  }
+}
+
+static void print_interface(outputStream* st, Klass* intf_klass, const char* intf_type, int indent) {
+  print_indent(st, indent);
+  st->print("  implements ");
+  print_classname(st, intf_klass);
+  st->print(" (%s intf)\n", intf_type);
+}
+
+void KlassHierarchy::print_class(outputStream* st, KlassInfoEntry* cie, bool print_interfaces) {
+  ResourceMark rm;
+  InstanceKlass* klass = (InstanceKlass*)cie->klass();
+  int indent = 0;
+
+  // Print indentation with proper indicators of superclass.
+  Klass* super = klass->super();
+  while (super != NULL) {
+    super = super->super();
+    indent++;
+  }
+  print_indent(st, indent);
+  if (indent != 0) st->print("--");
+
+  // Print the class name, its unique ClassLoader identifer, and if it is an interface.
+  print_classname(st, klass);
+  if (klass->is_interface()) {
+    st->print(" (intf)");
+  }
+  st->print("\n");
+
+  // Print any interfaces the class has.
+  if (print_interfaces) {
+    Array<Klass*>* local_intfs = klass->local_interfaces();
+    Array<Klass*>* trans_intfs = klass->transitive_interfaces();
+    for (int i = 0; i < local_intfs->length(); i++) {
+      print_interface(st, local_intfs->at(i), "declared", indent);
+    }
+    for (int i = 0; i < trans_intfs->length(); i++) {
+      Klass* trans_interface = trans_intfs->at(i);
+      // Only print transitive interfaces if they are not also declared.
+      if (!local_intfs->contains(trans_interface)) {
+        print_interface(st, trans_interface, "inherited", indent);
+      }
+    }
+  }
+}
+
+void KlassInfoHisto::print_class_stats(outputStream* st,
+                                      bool csv_format, const char *columns) {
+  ResourceMark rm;
+  KlassSizeStats sz, sz_sum;
+  int i;
+  julong *col_table = (julong*)(&sz);
+  julong *colsum_table = (julong*)(&sz_sum);
+  int width_table[KlassSizeStats::_num_columns];
+  bool selected[KlassSizeStats::_num_columns];
+
+  _selected_columns = columns;
+
+  memset(&sz_sum, 0, sizeof(sz_sum));
+  for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+    selected[c] = is_selected(name_table[c]);
+  }
+
+  for(i=0; i < elements()->length(); i++) {
+    elements()->at(i)->set_index(i+1);
+  }
+
+  // First iteration is for accumulating stats totals in colsum_table[].
+  // Second iteration is for printing stats for each class.
+  for (int pass=1; pass<=2; pass++) {
+    if (pass == 2) {
+      print_title(st, csv_format, selected, width_table, name_table);
+    }
+    for(i=0; i < elements()->length(); i++) {
+      KlassInfoEntry* e = (KlassInfoEntry*)elements()->at(i);
+      const Klass* k = e->klass();
+
+      // Get the stats for this class.
+      memset(&sz, 0, sizeof(sz));
+      sz._inst_count = e->count();
+      sz._inst_bytes = HeapWordSize * e->words();
+      k->collect_statistics(&sz);
+      sz._total_bytes = sz._ro_bytes + sz._rw_bytes;
+
+      if (pass == 1) {
+        // Add the stats for this class to the overall totals.
+        for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+          colsum_table[c] += col_table[c];
+        }
+      } else {
+        int super_index = -1;
+        // Print the stats for this class.
+        if (k->is_instance_klass()) {
+          Klass* super = k->super();
+          if (super) {
+            KlassInfoEntry* super_e = _cit->lookup(super);
+            if (super_e) {
+              super_index = super_e->index();
+            }
+          }
+        }
+
+        if (csv_format) {
+          st->print("%ld,%d", e->index(), super_index);
+          for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+            if (selected[c]) {st->print("," JULONG_FORMAT, col_table[c]);}
+          }
+          st->print(",%s",e->name());
+        } else {
+          st->print("%5ld %5d", e->index(), super_index);
+          for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+            if (selected[c]) {print_julong(st, width_table[c], col_table[c]);}
+          }
+          st->print(" %s", e->name());
+        }
+        if (is_selected("ClassLoader")) {
+          ClassLoaderData* loader_data = k->class_loader_data();
+          st->print(",");
+          loader_data->print_value_on(st);
+        }
+        st->cr();
+      }
+    }
+
+    if (pass == 1) {
+      // Calculate the minimum width needed for the column by accounting for the
+      // column header width and the width of the largest value in the column.
+      for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+        width_table[c] = col_width(colsum_table[c], name_table[c]);
+      }
+    }
+  }
+
+  sz_sum._inst_size = 0;
+
+  // Print the column totals.
+  if (csv_format) {
+    st->print(",");
+    for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+      if (selected[c]) {st->print("," JULONG_FORMAT, colsum_table[c]);}
+    }
+  } else {
+    st->print("           ");
+    for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+      if (selected[c]) {print_julong(st, width_table[c], colsum_table[c]);}
+    }
+    st->print(" Total");
+    if (sz_sum._total_bytes > 0) {
+      st->cr();
+      st->print("           ");
+      for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+        if (selected[c]) {
+          switch (c) {
+          case KlassSizeStats::_index_inst_size:
+          case KlassSizeStats::_index_inst_count:
+          case KlassSizeStats::_index_method_count:
+            st->print("%*s", width_table[c], "-");
+            break;
+          default:
+            {
+              double perc = (double)(100) * (double)(colsum_table[c]) / (double)sz_sum._total_bytes;
+              st->print("%*.1f%%", width_table[c]-1, perc);
+            }
+          }
+        }
+      }
+    }
+  }
+  st->cr();
+
+  if (!csv_format) {
+    print_title(st, csv_format, selected, width_table, name_table);
+  }
+}
+
+julong KlassInfoHisto::annotations_bytes(Array<AnnotationArray*>* p) const {
+  julong bytes = 0;
+  if (p != NULL) {
+    for (int i = 0; i < p->length(); i++) {
+      bytes += count_bytes_array(p->at(i));
+    }
+    bytes += count_bytes_array(p);
+  }
+  return bytes;
+}
+
+void KlassInfoHisto::print_histo_on(outputStream* st, bool print_stats,
+                                    bool csv_format, const char *columns) {
+  if (print_stats) {
+    print_class_stats(st, csv_format, columns);
+  } else {
+    st->print_cr(" num     #instances         #bytes  class name (module)");
+    st->print_cr("-------------------------------------------------------");
+    print_elements(st);
+  }
+}
+
+class HistoClosure : public KlassInfoClosure {
+ private:
+  KlassInfoHisto* _cih;
+ public:
+  HistoClosure(KlassInfoHisto* cih) : _cih(cih) {}
+
+  void do_cinfo(KlassInfoEntry* cie) {
+    _cih->add(cie);
+  }
+};
+
+class RecordInstanceClosure : public ObjectClosure {
+ private:
+  KlassInfoTable* _cit;
+  size_t _missed_count;
+  BoolObjectClosure* _filter;
+ public:
+  RecordInstanceClosure(KlassInfoTable* cit, BoolObjectClosure* filter) :
+    _cit(cit), _missed_count(0), _filter(filter) {}
+
+  void do_object(oop obj) {
+    if (should_visit(obj)) {
+      if (!_cit->record_instance(obj)) {
+        _missed_count++;
+      }
+    }
+  }
+
+  size_t missed_count() { return _missed_count; }
+
+ private:
+  bool should_visit(oop obj) {
+    return _filter == NULL || _filter->do_object_b(obj);
+  }
+};
+
+size_t HeapInspection::populate_table(KlassInfoTable* cit, BoolObjectClosure *filter) {
+  ResourceMark rm;
+
+  RecordInstanceClosure ric(cit, filter);
+  Universe::heap()->object_iterate(&ric);
+  return ric.missed_count();
+}
+
+void HeapInspection::heap_inspection(outputStream* st) {
+  ResourceMark rm;
+
+  if (_print_help) {
+    for (int c=0; c<KlassSizeStats::_num_columns; c++) {
+      st->print("%s:\n\t", name_table[c]);
+      const int max_col = 60;
+      int col = 0;
+      for (const char *p = help_table[c]; *p; p++,col++) {
+        if (col >= max_col && *p == ' ') {
+          st->print("\n\t");
+          col = 0;
+        } else {
+          st->print("%c", *p);
+        }
+      }
+      st->print_cr(".\n");
+    }
+    return;
+  }
+
+  KlassInfoTable cit(_print_class_stats);
+  if (!cit.allocation_failed()) {
+    // populate table with object allocation info
+    size_t missed_count = populate_table(&cit);
+    if (missed_count != 0) {
+      st->print_cr("WARNING: Ran out of C-heap; undercounted " SIZE_FORMAT
+                   " total instances in data below",
+                   missed_count);
+    }
+
+    // Sort and print klass instance info
+    KlassInfoHisto histo(&cit);
+    HistoClosure hc(&histo);
+
+    cit.iterate(&hc);
+
+    histo.sort();
+    histo.print_histo_on(st, _print_class_stats, _csv_format, _columns);
+  } else {
+    st->print_cr("ERROR: Ran out of C-heap; histogram not generated");
+  }
+  st->flush();
+}
+
+class FindInstanceClosure : public ObjectClosure {
+ private:
+  Klass* _klass;
+  GrowableArray<oop>* _result;
+
+ public:
+  FindInstanceClosure(Klass* k, GrowableArray<oop>* result) : _klass(k), _result(result) {};
+
+  void do_object(oop obj) {
+    if (obj->is_a(_klass)) {
+      _result->append(obj);
+    }
+  }
+};
+
+void HeapInspection::find_instances_at_safepoint(Klass* k, GrowableArray<oop>* result) {
+  assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
+  assert(Heap_lock->is_locked(), "should have the Heap_lock");
+
+  // Ensure that the heap is parsable
+  Universe::heap()->ensure_parsability(false);  // no need to retire TALBs
+
+  // Iterate over objects in the heap
+  FindInstanceClosure fic(k, result);
+  // If this operation encounters a bad object when using CMS,
+  // consider using safe_object_iterate() which avoids metadata
+  // objects that may contain bad references.
+  Universe::heap()->object_iterate(&fic);
+}