src/hotspot/share/oops/constantPool.cpp
changeset 47216 71c04702a3d5
parent 47103 a993ec29ec75
child 47532 d8e417df3468
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/oops/constantPool.cpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,2291 @@
+/*
+ * Copyright (c) 1997, 2017, 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/javaClasses.inline.hpp"
+#include "classfile/metadataOnStackMark.hpp"
+#include "classfile/stringTable.hpp"
+#include "classfile/systemDictionary.hpp"
+#include "classfile/vmSymbols.hpp"
+#include "interpreter/linkResolver.hpp"
+#include "memory/heapInspection.hpp"
+#include "memory/metadataFactory.hpp"
+#include "memory/metaspaceClosure.hpp"
+#include "memory/metaspaceShared.hpp"
+#include "memory/oopFactory.hpp"
+#include "memory/resourceArea.hpp"
+#include "oops/constantPool.hpp"
+#include "oops/instanceKlass.hpp"
+#include "oops/objArrayKlass.hpp"
+#include "oops/objArrayOop.inline.hpp"
+#include "oops/oop.inline.hpp"
+#include "prims/jvm.h"
+#include "runtime/fieldType.hpp"
+#include "runtime/init.hpp"
+#include "runtime/javaCalls.hpp"
+#include "runtime/signature.hpp"
+#include "runtime/vframe.hpp"
+#include "utilities/copy.hpp"
+#if INCLUDE_ALL_GCS
+#include "gc/g1/g1SATBCardTableModRefBS.hpp"
+#endif // INCLUDE_ALL_GCS
+
+ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
+  Array<u1>* tags = MetadataFactory::new_array<u1>(loader_data, length, 0, CHECK_NULL);
+  int size = ConstantPool::size(length);
+  return new (loader_data, size, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
+}
+
+#ifdef ASSERT
+
+// MetaspaceObj allocation invariant is calloc equivalent memory
+// simple verification of this here (JVM_CONSTANT_Invalid == 0 )
+static bool tag_array_is_zero_initialized(Array<u1>* tags) {
+  assert(tags != NULL, "invariant");
+  const int length = tags->length();
+  for (int index = 0; index < length; ++index) {
+    if (JVM_CONSTANT_Invalid != tags->at(index)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+#endif
+
+ConstantPool::ConstantPool(Array<u1>* tags) :
+  _tags(tags),
+  _length(tags->length()) {
+
+    assert(_tags != NULL, "invariant");
+    assert(tags->length() == _length, "invariant");
+    assert(tag_array_is_zero_initialized(tags), "invariant");
+    assert(0 == flags(), "invariant");
+    assert(0 == version(), "invariant");
+    assert(NULL == _pool_holder, "invariant");
+}
+
+void ConstantPool::deallocate_contents(ClassLoaderData* loader_data) {
+  if (cache() != NULL) {
+    MetadataFactory::free_metadata(loader_data, cache());
+    set_cache(NULL);
+  }
+
+  MetadataFactory::free_array<Klass*>(loader_data, resolved_klasses());
+  set_resolved_klasses(NULL);
+
+  MetadataFactory::free_array<jushort>(loader_data, operands());
+  set_operands(NULL);
+
+  release_C_heap_structures();
+
+  // free tag array
+  MetadataFactory::free_array<u1>(loader_data, tags());
+  set_tags(NULL);
+}
+
+void ConstantPool::release_C_heap_structures() {
+  // walk constant pool and decrement symbol reference counts
+  unreference_symbols();
+}
+
+void ConstantPool::metaspace_pointers_do(MetaspaceClosure* it) {
+  log_trace(cds)("Iter(ConstantPool): %p", this);
+
+  it->push(&_tags, MetaspaceClosure::_writable);
+  it->push(&_cache);
+  it->push(&_pool_holder);
+  it->push(&_operands);
+  it->push(&_resolved_klasses, MetaspaceClosure::_writable);
+
+  for (int i = 0; i < length(); i++) {
+    // The only MSO's embedded in the CP entries are Symbols:
+    //   JVM_CONSTANT_String (normal and pseudo)
+    //   JVM_CONSTANT_Utf8
+    constantTag ctag = tag_at(i);
+    if (ctag.is_string() || ctag.is_utf8()) {
+      it->push(symbol_at_addr(i));
+    }
+  }
+}
+
+objArrayOop ConstantPool::resolved_references() const {
+  return (objArrayOop)_cache->resolved_references();
+}
+
+// Create resolved_references array and mapping array for original cp indexes
+// The ldc bytecode was rewritten to have the resolved reference array index so need a way
+// to map it back for resolving and some unlikely miscellaneous uses.
+// The objects created by invokedynamic are appended to this list.
+void ConstantPool::initialize_resolved_references(ClassLoaderData* loader_data,
+                                                  const intStack& reference_map,
+                                                  int constant_pool_map_length,
+                                                  TRAPS) {
+  // Initialized the resolved object cache.
+  int map_length = reference_map.length();
+  if (map_length > 0) {
+    // Only need mapping back to constant pool entries.  The map isn't used for
+    // invokedynamic resolved_reference entries.  For invokedynamic entries,
+    // the constant pool cache index has the mapping back to both the constant
+    // pool and to the resolved reference index.
+    if (constant_pool_map_length > 0) {
+      Array<u2>* om = MetadataFactory::new_array<u2>(loader_data, constant_pool_map_length, CHECK);
+
+      for (int i = 0; i < constant_pool_map_length; i++) {
+        int x = reference_map.at(i);
+        assert(x == (int)(jushort) x, "klass index is too big");
+        om->at_put(i, (jushort)x);
+      }
+      set_reference_map(om);
+    }
+
+    // Create Java array for holding resolved strings, methodHandles,
+    // methodTypes, invokedynamic and invokehandle appendix objects, etc.
+    objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
+    Handle refs_handle (THREAD, (oop)stom);  // must handleize.
+    set_resolved_references(loader_data->add_handle(refs_handle));
+  }
+}
+
+void ConstantPool::allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS) {
+  // A ConstantPool can't possibly have 0xffff valid class entries,
+  // because entry #0 must be CONSTANT_Invalid, and each class entry must refer to a UTF8
+  // entry for the class's name. So at most we will have 0xfffe class entries.
+  // This allows us to use 0xffff (ConstantPool::_temp_resolved_klass_index) to indicate
+  // UnresolvedKlass entries that are temporarily created during class redefinition.
+  assert(num_klasses < CPKlassSlot::_temp_resolved_klass_index, "sanity");
+  assert(resolved_klasses() == NULL, "sanity");
+  Array<Klass*>* rk = MetadataFactory::new_array<Klass*>(loader_data, num_klasses, CHECK);
+  set_resolved_klasses(rk);
+}
+
+void ConstantPool::initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS) {
+  int len = length();
+  int num_klasses = 0;
+  for (int i = 1; i <len; i++) {
+    switch (tag_at(i).value()) {
+    case JVM_CONSTANT_ClassIndex:
+      {
+        const int class_index = klass_index_at(i);
+        unresolved_klass_at_put(i, class_index, num_klasses++);
+      }
+      break;
+#ifndef PRODUCT
+    case JVM_CONSTANT_Class:
+    case JVM_CONSTANT_UnresolvedClass:
+    case JVM_CONSTANT_UnresolvedClassInError:
+      // All of these should have been reverted back to ClassIndex before calling
+      // this function.
+      ShouldNotReachHere();
+#endif
+    }
+  }
+  allocate_resolved_klasses(loader_data, num_klasses, THREAD);
+}
+
+// Anonymous class support:
+void ConstantPool::klass_at_put(int class_index, int name_index, int resolved_klass_index, Klass* k, Symbol* name) {
+  assert(is_within_bounds(class_index), "index out of bounds");
+  assert(is_within_bounds(name_index), "index out of bounds");
+  assert((resolved_klass_index & 0xffff0000) == 0, "must be");
+  *int_at_addr(class_index) =
+    build_int_from_shorts((jushort)resolved_klass_index, (jushort)name_index);
+
+  symbol_at_put(name_index, name);
+  name->increment_refcount();
+  Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
+  OrderAccess::release_store_ptr((Klass* volatile *)adr, k);
+
+  // The interpreter assumes when the tag is stored, the klass is resolved
+  // and the Klass* non-NULL, so we need hardware store ordering here.
+  if (k != NULL) {
+    release_tag_at_put(class_index, JVM_CONSTANT_Class);
+  } else {
+    release_tag_at_put(class_index, JVM_CONSTANT_UnresolvedClass);
+  }
+}
+
+// Anonymous class support:
+void ConstantPool::klass_at_put(int class_index, Klass* k) {
+  assert(k != NULL, "must be valid klass");
+  CPKlassSlot kslot = klass_slot_at(class_index);
+  int resolved_klass_index = kslot.resolved_klass_index();
+  Klass** adr = resolved_klasses()->adr_at(resolved_klass_index);
+  OrderAccess::release_store_ptr((Klass* volatile *)adr, k);
+
+  // The interpreter assumes when the tag is stored, the klass is resolved
+  // and the Klass* non-NULL, so we need hardware store ordering here.
+  release_tag_at_put(class_index, JVM_CONSTANT_Class);
+}
+
+#if INCLUDE_CDS_JAVA_HEAP
+// Archive the resolved references
+void ConstantPool::archive_resolved_references(Thread* THREAD) {
+  if (_cache == NULL) {
+    return; // nothing to do
+  }
+
+  InstanceKlass *ik = pool_holder();
+  if (!(ik->is_shared_boot_class() || ik->is_shared_platform_class() ||
+        ik->is_shared_app_class())) {
+    // Archiving resolved references for classes from non-builtin loaders
+    // is not yet supported.
+    set_resolved_references(NULL);
+    return;
+  }
+
+  objArrayOop rr = resolved_references();
+  Array<u2>* ref_map = reference_map();
+  if (rr != NULL) {
+    int ref_map_len = ref_map == NULL ? 0 : ref_map->length();
+    int rr_len = rr->length();
+    for (int i = 0; i < rr_len; i++) {
+      oop p = rr->obj_at(i);
+      rr->obj_at_put(i, NULL);
+      if (p != NULL && i < ref_map_len) {
+        int index = object_to_cp_index(i);
+        // Skip the entry if the string hash code is 0 since the string
+        // is not included in the shared string_table, see StringTable::copy_shared_string.
+        if (tag_at(index).is_string() && java_lang_String::hash_code(p) != 0) {
+          oop op = StringTable::create_archived_string(p, THREAD);
+          // If the String object is not archived (possibly too large),
+          // NULL is returned. Also set it in the array, so we won't
+          // have a 'bad' reference in the archived resolved_reference
+          // array.
+          rr->obj_at_put(i, op);
+        }
+      }
+    }
+
+    oop archived = MetaspaceShared::archive_heap_object(rr, THREAD);
+    _cache->set_archived_references(archived);
+    set_resolved_references(NULL);
+  }
+}
+#endif
+
+// CDS support. Create a new resolved_references array.
+void ConstantPool::restore_unshareable_info(TRAPS) {
+  assert(is_constantPool(), "ensure C++ vtable is restored");
+  assert(on_stack(), "should always be set for shared constant pools");
+  assert(is_shared(), "should always be set for shared constant pools");
+  assert(_cache != NULL, "constant pool _cache should not be NULL");
+
+  // Only create the new resolved references array if it hasn't been attempted before
+  if (resolved_references() != NULL) return;
+
+  // restore the C++ vtable from the shared archive
+  restore_vtable();
+
+  if (SystemDictionary::Object_klass_loaded()) {
+    ClassLoaderData* loader_data = pool_holder()->class_loader_data();
+#if INCLUDE_CDS_JAVA_HEAP
+    if (MetaspaceShared::open_archive_heap_region_mapped() &&
+        _cache->archived_references() != NULL) {
+      oop archived = _cache->archived_references();
+      // Make sure GC knows the cached object is now live. This is necessary after
+      // initial GC marking and during concurrent marking as strong roots are only
+      // scanned during initial marking (at the start of the GC marking).
+      assert(UseG1GC, "Requires G1 GC");
+      G1SATBCardTableModRefBS::enqueue(archived);
+      // Create handle for the archived resolved reference array object
+      Handle refs_handle(THREAD, (oop)archived);
+      set_resolved_references(loader_data->add_handle(refs_handle));
+    } else
+#endif
+    {
+      // No mapped archived resolved reference array
+      // Recreate the object array and add to ClassLoaderData.
+      int map_length = resolved_reference_length();
+      if (map_length > 0) {
+        objArrayOop stom = oopFactory::new_objArray(SystemDictionary::Object_klass(), map_length, CHECK);
+        Handle refs_handle(THREAD, (oop)stom);  // must handleize.
+        set_resolved_references(loader_data->add_handle(refs_handle));
+      }
+    }
+  }
+}
+
+void ConstantPool::remove_unshareable_info() {
+  // Resolved references are not in the shared archive.
+  // Save the length for restoration.  It is not necessarily the same length
+  // as reference_map.length() if invokedynamic is saved. It is needed when
+  // re-creating the resolved reference array if archived heap data cannot be map
+  // at runtime.
+  set_resolved_reference_length(
+    resolved_references() != NULL ? resolved_references()->length() : 0);
+
+  // If archiving heap objects is not allowed, clear the resolved references.
+  // Otherwise, it is cleared after the resolved references array is cached
+  // (see archive_resolved_references()).
+  if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
+    set_resolved_references(NULL);
+  }
+
+  // Shared ConstantPools are in the RO region, so the _flags cannot be modified.
+  // The _on_stack flag is used to prevent ConstantPools from deallocation during
+  // class redefinition. Since shared ConstantPools cannot be deallocated anyway,
+  // we always set _on_stack to true to avoid having to change _flags during runtime.
+  _flags |= (_on_stack | _is_shared);
+  int num_klasses = 0;
+  for (int index = 1; index < length(); index++) { // Index 0 is unused
+    assert(!tag_at(index).is_unresolved_klass_in_error(), "This must not happen during dump time");
+    if (tag_at(index).is_klass()) {
+      // This class was resolved as a side effect of executing Java code
+      // during dump time. We need to restore it back to an UnresolvedClass,
+      // so that the proper class loading and initialization can happen
+      // at runtime.
+      CPKlassSlot kslot = klass_slot_at(index);
+      int resolved_klass_index = kslot.resolved_klass_index();
+      int name_index = kslot.name_index();
+      assert(tag_at(name_index).is_symbol(), "sanity");
+      resolved_klasses()->at_put(resolved_klass_index, NULL);
+      tag_at_put(index, JVM_CONSTANT_UnresolvedClass);
+      assert(klass_name_at(index) == symbol_at(name_index), "sanity");
+    }
+  }
+  if (cache() != NULL) {
+    cache()->remove_unshareable_info();
+  }
+}
+
+int ConstantPool::cp_to_object_index(int cp_index) {
+  // this is harder don't do this so much.
+  int i = reference_map()->find(cp_index);
+  // We might not find the index for jsr292 call.
+  return (i < 0) ? _no_index_sentinel : i;
+}
+
+void ConstantPool::string_at_put(int which, int obj_index, oop str) {
+  resolved_references()->obj_at_put(obj_index, str);
+}
+
+void ConstantPool::trace_class_resolution(const constantPoolHandle& this_cp, Klass* k) {
+  ResourceMark rm;
+  int line_number = -1;
+  const char * source_file = NULL;
+  if (JavaThread::current()->has_last_Java_frame()) {
+    // try to identify the method which called this function.
+    vframeStream vfst(JavaThread::current());
+    if (!vfst.at_end()) {
+      line_number = vfst.method()->line_number_from_bci(vfst.bci());
+      Symbol* s = vfst.method()->method_holder()->source_file_name();
+      if (s != NULL) {
+        source_file = s->as_C_string();
+      }
+    }
+  }
+  if (k != this_cp->pool_holder()) {
+    // only print something if the classes are different
+    if (source_file != NULL) {
+      log_debug(class, resolve)("%s %s %s:%d",
+                 this_cp->pool_holder()->external_name(),
+                 k->external_name(), source_file, line_number);
+    } else {
+      log_debug(class, resolve)("%s %s",
+                 this_cp->pool_holder()->external_name(),
+                 k->external_name());
+    }
+  }
+}
+
+Klass* ConstantPool::klass_at_impl(const constantPoolHandle& this_cp, int which,
+                                   bool save_resolution_error, TRAPS) {
+  assert(THREAD->is_Java_thread(), "must be a Java thread");
+
+  // A resolved constantPool entry will contain a Klass*, otherwise a Symbol*.
+  // It is not safe to rely on the tag bit's here, since we don't have a lock, and
+  // the entry and tag is not updated atomicly.
+  CPKlassSlot kslot = this_cp->klass_slot_at(which);
+  int resolved_klass_index = kslot.resolved_klass_index();
+  int name_index = kslot.name_index();
+  assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
+
+  Klass* klass = this_cp->resolved_klasses()->at(resolved_klass_index);
+  if (klass != NULL) {
+    return klass;
+  }
+
+  // This tag doesn't change back to unresolved class unless at a safepoint.
+  if (this_cp->tag_at(which).is_unresolved_klass_in_error()) {
+    // The original attempt to resolve this constant pool entry failed so find the
+    // class of the original error and throw another error of the same class
+    // (JVMS 5.4.3).
+    // If there is a detail message, pass that detail message to the error.
+    // The JVMS does not strictly require us to duplicate the same detail message,
+    // or any internal exception fields such as cause or stacktrace.  But since the
+    // detail message is often a class name or other literal string, we will repeat it
+    // if we can find it in the symbol table.
+    throw_resolution_error(this_cp, which, CHECK_0);
+    ShouldNotReachHere();
+  }
+
+  Handle mirror_handle;
+  Symbol* name = this_cp->symbol_at(name_index);
+  Handle loader (THREAD, this_cp->pool_holder()->class_loader());
+  Handle protection_domain (THREAD, this_cp->pool_holder()->protection_domain());
+  Klass* k = SystemDictionary::resolve_or_fail(name, loader, protection_domain, true, THREAD);
+  if (!HAS_PENDING_EXCEPTION) {
+    // preserve the resolved klass from unloading
+    mirror_handle = Handle(THREAD, k->java_mirror());
+    // Do access check for klasses
+    verify_constant_pool_resolve(this_cp, k, THREAD);
+  }
+
+  // Failed to resolve class. We must record the errors so that subsequent attempts
+  // to resolve this constant pool entry fail with the same error (JVMS 5.4.3).
+  if (HAS_PENDING_EXCEPTION) {
+    if (save_resolution_error) {
+      save_and_throw_exception(this_cp, which, constantTag(JVM_CONSTANT_UnresolvedClass), CHECK_NULL);
+      // If CHECK_NULL above doesn't return the exception, that means that
+      // some other thread has beaten us and has resolved the class.
+      // To preserve old behavior, we return the resolved class.
+      klass = this_cp->resolved_klasses()->at(resolved_klass_index);
+      assert(klass != NULL, "must be resolved if exception was cleared");
+      return klass;
+    } else {
+      return NULL;  // return the pending exception
+    }
+  }
+
+  // Make this class loader depend upon the class loader owning the class reference
+  ClassLoaderData* this_key = this_cp->pool_holder()->class_loader_data();
+  this_key->record_dependency(k, CHECK_NULL); // Can throw OOM
+
+  // logging for class+resolve.
+  if (log_is_enabled(Debug, class, resolve)){
+    trace_class_resolution(this_cp, k);
+  }
+  Klass** adr = this_cp->resolved_klasses()->adr_at(resolved_klass_index);
+  OrderAccess::release_store_ptr((Klass* volatile *)adr, k);
+  // The interpreter assumes when the tag is stored, the klass is resolved
+  // and the Klass* stored in _resolved_klasses is non-NULL, so we need
+  // hardware store ordering here.
+  this_cp->release_tag_at_put(which, JVM_CONSTANT_Class);
+  return k;
+}
+
+
+// Does not update ConstantPool* - to avoid any exception throwing. Used
+// by compiler and exception handling.  Also used to avoid classloads for
+// instanceof operations. Returns NULL if the class has not been loaded or
+// if the verification of constant pool failed
+Klass* ConstantPool::klass_at_if_loaded(const constantPoolHandle& this_cp, int which) {
+  CPKlassSlot kslot = this_cp->klass_slot_at(which);
+  int resolved_klass_index = kslot.resolved_klass_index();
+  int name_index = kslot.name_index();
+  assert(this_cp->tag_at(name_index).is_symbol(), "sanity");
+
+  Klass* k = this_cp->resolved_klasses()->at(resolved_klass_index);
+  if (k != NULL) {
+    return k;
+  } else {
+    Thread *thread = Thread::current();
+    Symbol* name = this_cp->symbol_at(name_index);
+    oop loader = this_cp->pool_holder()->class_loader();
+    oop protection_domain = this_cp->pool_holder()->protection_domain();
+    Handle h_prot (thread, protection_domain);
+    Handle h_loader (thread, loader);
+    Klass* k = SystemDictionary::find(name, h_loader, h_prot, thread);
+
+    if (k != NULL) {
+      // Make sure that resolving is legal
+      EXCEPTION_MARK;
+      // return NULL if verification fails
+      verify_constant_pool_resolve(this_cp, k, THREAD);
+      if (HAS_PENDING_EXCEPTION) {
+        CLEAR_PENDING_EXCEPTION;
+        return NULL;
+      }
+      return k;
+    } else {
+      return k;
+    }
+  }
+}
+
+
+Klass* ConstantPool::klass_ref_at_if_loaded(const constantPoolHandle& this_cp, int which) {
+  return klass_at_if_loaded(this_cp, this_cp->klass_ref_index_at(which));
+}
+
+
+Method* ConstantPool::method_at_if_loaded(const constantPoolHandle& cpool,
+                                                   int which) {
+  if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
+  int cache_index = decode_cpcache_index(which, true);
+  if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
+    // FIXME: should be an assert
+    log_debug(class, resolve)("bad operand %d in:", which); cpool->print();
+    return NULL;
+  }
+  ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
+  return e->method_if_resolved(cpool);
+}
+
+
+bool ConstantPool::has_appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
+  if (cpool->cache() == NULL)  return false;  // nothing to load yet
+  int cache_index = decode_cpcache_index(which, true);
+  ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
+  return e->has_appendix();
+}
+
+oop ConstantPool::appendix_at_if_loaded(const constantPoolHandle& cpool, int which) {
+  if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
+  int cache_index = decode_cpcache_index(which, true);
+  ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
+  return e->appendix_if_resolved(cpool);
+}
+
+
+bool ConstantPool::has_method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
+  if (cpool->cache() == NULL)  return false;  // nothing to load yet
+  int cache_index = decode_cpcache_index(which, true);
+  ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
+  return e->has_method_type();
+}
+
+oop ConstantPool::method_type_at_if_loaded(const constantPoolHandle& cpool, int which) {
+  if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
+  int cache_index = decode_cpcache_index(which, true);
+  ConstantPoolCacheEntry* e = cpool->cache()->entry_at(cache_index);
+  return e->method_type_if_resolved(cpool);
+}
+
+
+Symbol* ConstantPool::impl_name_ref_at(int which, bool uncached) {
+  int name_index = name_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
+  return symbol_at(name_index);
+}
+
+
+Symbol* ConstantPool::impl_signature_ref_at(int which, bool uncached) {
+  int signature_index = signature_ref_index_at(impl_name_and_type_ref_index_at(which, uncached));
+  return symbol_at(signature_index);
+}
+
+
+int ConstantPool::impl_name_and_type_ref_index_at(int which, bool uncached) {
+  int i = which;
+  if (!uncached && cache() != NULL) {
+    if (ConstantPool::is_invokedynamic_index(which)) {
+      // Invokedynamic index is index into the constant pool cache
+      int pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
+      pool_index = invoke_dynamic_name_and_type_ref_index_at(pool_index);
+      assert(tag_at(pool_index).is_name_and_type(), "");
+      return pool_index;
+    }
+    // change byte-ordering and go via cache
+    i = remap_instruction_operand_from_cache(which);
+  } else {
+    if (tag_at(which).is_invoke_dynamic()) {
+      int pool_index = invoke_dynamic_name_and_type_ref_index_at(which);
+      assert(tag_at(pool_index).is_name_and_type(), "");
+      return pool_index;
+    }
+  }
+  assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
+  assert(!tag_at(i).is_invoke_dynamic(), "Must be handled above");
+  jint ref_index = *int_at_addr(i);
+  return extract_high_short_from_int(ref_index);
+}
+
+constantTag ConstantPool::impl_tag_ref_at(int which, bool uncached) {
+  int pool_index = which;
+  if (!uncached && cache() != NULL) {
+    if (ConstantPool::is_invokedynamic_index(which)) {
+      // Invokedynamic index is index into resolved_references
+      pool_index = invokedynamic_cp_cache_entry_at(which)->constant_pool_index();
+    } else {
+      // change byte-ordering and go via cache
+      pool_index = remap_instruction_operand_from_cache(which);
+    }
+  }
+  return tag_at(pool_index);
+}
+
+int ConstantPool::impl_klass_ref_index_at(int which, bool uncached) {
+  guarantee(!ConstantPool::is_invokedynamic_index(which),
+            "an invokedynamic instruction does not have a klass");
+  int i = which;
+  if (!uncached && cache() != NULL) {
+    // change byte-ordering and go via cache
+    i = remap_instruction_operand_from_cache(which);
+  }
+  assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
+  jint ref_index = *int_at_addr(i);
+  return extract_low_short_from_int(ref_index);
+}
+
+
+
+int ConstantPool::remap_instruction_operand_from_cache(int operand) {
+  int cpc_index = operand;
+  DEBUG_ONLY(cpc_index -= CPCACHE_INDEX_TAG);
+  assert((int)(u2)cpc_index == cpc_index, "clean u2");
+  int member_index = cache()->entry_at(cpc_index)->constant_pool_index();
+  return member_index;
+}
+
+
+void ConstantPool::verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* k, TRAPS) {
+ if (k->is_instance_klass() || k->is_objArray_klass()) {
+    InstanceKlass* holder = this_cp->pool_holder();
+    Klass* elem = k->is_instance_klass() ? k : ObjArrayKlass::cast(k)->bottom_klass();
+
+    // The element type could be a typeArray - we only need the access check if it is
+    // an reference to another class
+    if (elem->is_instance_klass()) {
+      LinkResolver::check_klass_accessability(holder, elem, CHECK);
+    }
+  }
+}
+
+
+int ConstantPool::name_ref_index_at(int which_nt) {
+  jint ref_index = name_and_type_at(which_nt);
+  return extract_low_short_from_int(ref_index);
+}
+
+
+int ConstantPool::signature_ref_index_at(int which_nt) {
+  jint ref_index = name_and_type_at(which_nt);
+  return extract_high_short_from_int(ref_index);
+}
+
+
+Klass* ConstantPool::klass_ref_at(int which, TRAPS) {
+  return klass_at(klass_ref_index_at(which), THREAD);
+}
+
+Symbol* ConstantPool::klass_name_at(int which) const {
+  return symbol_at(klass_slot_at(which).name_index());
+}
+
+Symbol* ConstantPool::klass_ref_at_noresolve(int which) {
+  jint ref_index = klass_ref_index_at(which);
+  return klass_at_noresolve(ref_index);
+}
+
+Symbol* ConstantPool::uncached_klass_ref_at_noresolve(int which) {
+  jint ref_index = uncached_klass_ref_index_at(which);
+  return klass_at_noresolve(ref_index);
+}
+
+char* ConstantPool::string_at_noresolve(int which) {
+  return unresolved_string_at(which)->as_C_string();
+}
+
+BasicType ConstantPool::basic_type_for_signature_at(int which) const {
+  return FieldType::basic_type(symbol_at(which));
+}
+
+
+void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS) {
+  for (int index = 1; index < this_cp->length(); index++) { // Index 0 is unused
+    if (this_cp->tag_at(index).is_string()) {
+      this_cp->string_at(index, CHECK);
+    }
+  }
+}
+
+bool ConstantPool::resolve_class_constants(TRAPS) {
+  constantPoolHandle cp(THREAD, this);
+  for (int index = 1; index < length(); index++) { // Index 0 is unused
+    if (tag_at(index).is_string()) {
+      Symbol* sym = cp->unresolved_string_at(index);
+      // Look up only. Only resolve references to already interned strings.
+      oop str = StringTable::lookup(sym);
+      if (str != NULL) {
+        int cache_index = cp->cp_to_object_index(index);
+        cp->string_at_put(index, cache_index, str);
+      }
+    }
+  }
+  return true;
+}
+
+Symbol* ConstantPool::exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
+  // Dig out the detailed message to reuse if possible
+  Symbol* message = java_lang_Throwable::detail_message(pending_exception);
+  if (message != NULL) {
+    return message;
+  }
+
+  // Return specific message for the tag
+  switch (tag.value()) {
+  case JVM_CONSTANT_UnresolvedClass:
+    // return the class name in the error message
+    message = this_cp->klass_name_at(which);
+    break;
+  case JVM_CONSTANT_MethodHandle:
+    // return the method handle name in the error message
+    message = this_cp->method_handle_name_ref_at(which);
+    break;
+  case JVM_CONSTANT_MethodType:
+    // return the method type signature in the error message
+    message = this_cp->method_type_signature_at(which);
+    break;
+  default:
+    ShouldNotReachHere();
+  }
+
+  return message;
+}
+
+void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
+  Symbol* message = NULL;
+  Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message);
+  assert(error != NULL && message != NULL, "checking");
+  CLEAR_PENDING_EXCEPTION;
+  ResourceMark rm;
+  THROW_MSG(error, message->as_C_string());
+}
+
+// If resolution for Class, MethodHandle or MethodType fails, save the exception
+// in the resolution error table, so that the same exception is thrown again.
+void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, int which,
+                                            constantTag tag, TRAPS) {
+  Symbol* error = PENDING_EXCEPTION->klass()->name();
+
+  int error_tag = tag.error_value();
+
+  if (!PENDING_EXCEPTION->
+    is_a(SystemDictionary::LinkageError_klass())) {
+    // Just throw the exception and don't prevent these classes from
+    // being loaded due to virtual machine errors like StackOverflow
+    // and OutOfMemoryError, etc, or if the thread was hit by stop()
+    // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
+  } else if (this_cp->tag_at(which).value() != error_tag) {
+    Symbol* message = exception_message(this_cp, which, tag, PENDING_EXCEPTION);
+    SystemDictionary::add_resolution_error(this_cp, which, error, message);
+    // CAS in the tag.  If a thread beat us to registering this error that's fine.
+    // If another thread resolved the reference, this is a race condition. This
+    // thread may have had a security manager or something temporary.
+    // This doesn't deterministically get an error.   So why do we save this?
+    // We save this because jvmti can add classes to the bootclass path after
+    // this error, so it needs to get the same error if the error is first.
+    jbyte old_tag = Atomic::cmpxchg((jbyte)error_tag,
+                            (jbyte*)this_cp->tag_addr_at(which), (jbyte)tag.value());
+    if (old_tag != error_tag && old_tag != tag.value()) {
+      // MethodHandles and MethodType doesn't change to resolved version.
+      assert(this_cp->tag_at(which).is_klass(), "Wrong tag value");
+      // Forget the exception and use the resolved class.
+      CLEAR_PENDING_EXCEPTION;
+    }
+  } else {
+    // some other thread put this in error state
+    throw_resolution_error(this_cp, which, CHECK);
+  }
+}
+
+// Called to resolve constants in the constant pool and return an oop.
+// Some constant pool entries cache their resolved oop. This is also
+// called to create oops from constants to use in arguments for invokedynamic
+oop ConstantPool::resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS) {
+  oop result_oop = NULL;
+  Handle throw_exception;
+
+  if (cache_index == _possible_index_sentinel) {
+    // It is possible that this constant is one which is cached in the objects.
+    // We'll do a linear search.  This should be OK because this usage is rare.
+    assert(index > 0, "valid index");
+    cache_index = this_cp->cp_to_object_index(index);
+  }
+  assert(cache_index == _no_index_sentinel || cache_index >= 0, "");
+  assert(index == _no_index_sentinel || index >= 0, "");
+
+  if (cache_index >= 0) {
+    result_oop = this_cp->resolved_references()->obj_at(cache_index);
+    if (result_oop != NULL) {
+      return result_oop;
+      // That was easy...
+    }
+    index = this_cp->object_to_cp_index(cache_index);
+  }
+
+  jvalue prim_value;  // temp used only in a few cases below
+
+  constantTag tag = this_cp->tag_at(index);
+
+  switch (tag.value()) {
+
+  case JVM_CONSTANT_UnresolvedClass:
+  case JVM_CONSTANT_UnresolvedClassInError:
+  case JVM_CONSTANT_Class:
+    {
+      assert(cache_index == _no_index_sentinel, "should not have been set");
+      Klass* resolved = klass_at_impl(this_cp, index, true, CHECK_NULL);
+      // ldc wants the java mirror.
+      result_oop = resolved->java_mirror();
+      break;
+    }
+
+  case JVM_CONSTANT_String:
+    assert(cache_index != _no_index_sentinel, "should have been set");
+    if (this_cp->is_pseudo_string_at(index)) {
+      result_oop = this_cp->pseudo_string_at(index, cache_index);
+      break;
+    }
+    result_oop = string_at_impl(this_cp, index, cache_index, CHECK_NULL);
+    break;
+
+  case JVM_CONSTANT_MethodHandleInError:
+  case JVM_CONSTANT_MethodTypeInError:
+    {
+      throw_resolution_error(this_cp, index, CHECK_NULL);
+      break;
+    }
+
+  case JVM_CONSTANT_MethodHandle:
+    {
+      int ref_kind                 = this_cp->method_handle_ref_kind_at(index);
+      int callee_index             = this_cp->method_handle_klass_index_at(index);
+      Symbol*  name =      this_cp->method_handle_name_ref_at(index);
+      Symbol*  signature = this_cp->method_handle_signature_ref_at(index);
+      constantTag m_tag  = this_cp->tag_at(this_cp->method_handle_index_at(index));
+      { ResourceMark rm(THREAD);
+        log_debug(class, resolve)("resolve JVM_CONSTANT_MethodHandle:%d [%d/%d/%d] %s.%s",
+                              ref_kind, index, this_cp->method_handle_index_at(index),
+                              callee_index, name->as_C_string(), signature->as_C_string());
+      }
+
+      Klass* callee = klass_at_impl(this_cp, callee_index, true, CHECK_NULL);
+
+      // Check constant pool method consistency
+      if ((callee->is_interface() && m_tag.is_method()) ||
+          ((!callee->is_interface() && m_tag.is_interface_method()))) {
+        ResourceMark rm(THREAD);
+        char buf[400];
+        jio_snprintf(buf, sizeof(buf),
+          "Inconsistent constant pool data in classfile for class %s. "
+          "Method %s%s at index %d is %s and should be %s",
+          callee->name()->as_C_string(), name->as_C_string(), signature->as_C_string(), index,
+          callee->is_interface() ? "CONSTANT_MethodRef" : "CONSTANT_InterfaceMethodRef",
+          callee->is_interface() ? "CONSTANT_InterfaceMethodRef" : "CONSTANT_MethodRef");
+        THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), buf);
+      }
+
+      Klass* klass = this_cp->pool_holder();
+      Handle value = SystemDictionary::link_method_handle_constant(klass, ref_kind,
+                                                                   callee, name, signature,
+                                                                   THREAD);
+      result_oop = value();
+      if (HAS_PENDING_EXCEPTION) {
+        save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
+      }
+      break;
+    }
+
+  case JVM_CONSTANT_MethodType:
+    {
+      Symbol*  signature = this_cp->method_type_signature_at(index);
+      { ResourceMark rm(THREAD);
+        log_debug(class, resolve)("resolve JVM_CONSTANT_MethodType [%d/%d] %s",
+                              index, this_cp->method_type_index_at(index),
+                              signature->as_C_string());
+      }
+      Klass* klass = this_cp->pool_holder();
+      Handle value = SystemDictionary::find_method_handle_type(signature, klass, THREAD);
+      result_oop = value();
+      if (HAS_PENDING_EXCEPTION) {
+        save_and_throw_exception(this_cp, index, tag, CHECK_NULL);
+      }
+      break;
+    }
+
+  case JVM_CONSTANT_Integer:
+    assert(cache_index == _no_index_sentinel, "should not have been set");
+    prim_value.i = this_cp->int_at(index);
+    result_oop = java_lang_boxing_object::create(T_INT, &prim_value, CHECK_NULL);
+    break;
+
+  case JVM_CONSTANT_Float:
+    assert(cache_index == _no_index_sentinel, "should not have been set");
+    prim_value.f = this_cp->float_at(index);
+    result_oop = java_lang_boxing_object::create(T_FLOAT, &prim_value, CHECK_NULL);
+    break;
+
+  case JVM_CONSTANT_Long:
+    assert(cache_index == _no_index_sentinel, "should not have been set");
+    prim_value.j = this_cp->long_at(index);
+    result_oop = java_lang_boxing_object::create(T_LONG, &prim_value, CHECK_NULL);
+    break;
+
+  case JVM_CONSTANT_Double:
+    assert(cache_index == _no_index_sentinel, "should not have been set");
+    prim_value.d = this_cp->double_at(index);
+    result_oop = java_lang_boxing_object::create(T_DOUBLE, &prim_value, CHECK_NULL);
+    break;
+
+  default:
+    DEBUG_ONLY( tty->print_cr("*** %p: tag at CP[%d/%d] = %d",
+                              this_cp(), index, cache_index, tag.value()));
+    assert(false, "unexpected constant tag");
+    break;
+  }
+
+  if (cache_index >= 0) {
+    // Benign race condition:  resolved_references may already be filled in.
+    // The important thing here is that all threads pick up the same result.
+    // It doesn't matter which racing thread wins, as long as only one
+    // result is used by all threads, and all future queries.
+    oop old_result = this_cp->resolved_references()->atomic_compare_exchange_oop(cache_index, result_oop, NULL);
+    if (old_result == NULL) {
+      return result_oop;  // was installed
+    } else {
+      // Return the winning thread's result.  This can be different than
+      // the result here for MethodHandles.
+      return old_result;
+    }
+  } else {
+    return result_oop;
+  }
+}
+
+oop ConstantPool::uncached_string_at(int which, TRAPS) {
+  Symbol* sym = unresolved_string_at(which);
+  oop str = StringTable::intern(sym, CHECK_(NULL));
+  assert(java_lang_String::is_instance(str), "must be string");
+  return str;
+}
+
+
+oop ConstantPool::resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS) {
+  assert(this_cp->tag_at(index).is_invoke_dynamic(), "Corrupted constant pool");
+
+  Handle bsm;
+  int argc;
+  {
+    // JVM_CONSTANT_InvokeDynamic is an ordered pair of [bootm, name&type], plus optional arguments
+    // The bootm, being a JVM_CONSTANT_MethodHandle, has its own cache entry.
+    // It is accompanied by the optional arguments.
+    int bsm_index = this_cp->invoke_dynamic_bootstrap_method_ref_index_at(index);
+    oop bsm_oop = this_cp->resolve_possibly_cached_constant_at(bsm_index, CHECK_NULL);
+    if (!java_lang_invoke_MethodHandle::is_instance(bsm_oop)) {
+      THROW_MSG_NULL(vmSymbols::java_lang_LinkageError(), "BSM not an MethodHandle");
+    }
+
+    // Extract the optional static arguments.
+    argc = this_cp->invoke_dynamic_argument_count_at(index);
+    if (argc == 0)  return bsm_oop;
+
+    bsm = Handle(THREAD, bsm_oop);
+  }
+
+  objArrayHandle info;
+  {
+    objArrayOop info_oop = oopFactory::new_objArray(SystemDictionary::Object_klass(), 1+argc, CHECK_NULL);
+    info = objArrayHandle(THREAD, info_oop);
+  }
+
+  info->obj_at_put(0, bsm());
+  for (int i = 0; i < argc; i++) {
+    int arg_index = this_cp->invoke_dynamic_argument_index_at(index, i);
+    oop arg_oop = this_cp->resolve_possibly_cached_constant_at(arg_index, CHECK_NULL);
+    info->obj_at_put(1+i, arg_oop);
+  }
+
+  return info();
+}
+
+oop ConstantPool::string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS) {
+  // If the string has already been interned, this entry will be non-null
+  oop str = this_cp->resolved_references()->obj_at(obj_index);
+  if (str != NULL) return str;
+  Symbol* sym = this_cp->unresolved_string_at(which);
+  str = StringTable::intern(sym, CHECK_(NULL));
+  this_cp->string_at_put(which, obj_index, str);
+  assert(java_lang_String::is_instance(str), "must be string");
+  return str;
+}
+
+
+bool ConstantPool::klass_name_at_matches(const InstanceKlass* k, int which) {
+  // Names are interned, so we can compare Symbol*s directly
+  Symbol* cp_name = klass_name_at(which);
+  return (cp_name == k->name());
+}
+
+
+// Iterate over symbols and decrement ones which are Symbol*s
+// This is done during GC.
+// Only decrement the UTF8 symbols. Strings point to
+// these symbols but didn't increment the reference count.
+void ConstantPool::unreference_symbols() {
+  for (int index = 1; index < length(); index++) { // Index 0 is unused
+    constantTag tag = tag_at(index);
+    if (tag.is_symbol()) {
+      symbol_at(index)->decrement_refcount();
+    }
+  }
+}
+
+
+// Compare this constant pool's entry at index1 to the constant pool
+// cp2's entry at index2.
+bool ConstantPool::compare_entry_to(int index1, const constantPoolHandle& cp2,
+       int index2, TRAPS) {
+
+  // The error tags are equivalent to non-error tags when comparing
+  jbyte t1 = tag_at(index1).non_error_value();
+  jbyte t2 = cp2->tag_at(index2).non_error_value();
+
+  if (t1 != t2) {
+    // Not the same entry type so there is nothing else to check. Note
+    // that this style of checking will consider resolved/unresolved
+    // class pairs as different.
+    // From the ConstantPool* API point of view, this is correct
+    // behavior. See VM_RedefineClasses::merge_constant_pools() to see how this
+    // plays out in the context of ConstantPool* merging.
+    return false;
+  }
+
+  switch (t1) {
+  case JVM_CONSTANT_Class:
+  {
+    Klass* k1 = klass_at(index1, CHECK_false);
+    Klass* k2 = cp2->klass_at(index2, CHECK_false);
+    if (k1 == k2) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_ClassIndex:
+  {
+    int recur1 = klass_index_at(index1);
+    int recur2 = cp2->klass_index_at(index2);
+    bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
+    if (match) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_Double:
+  {
+    jdouble d1 = double_at(index1);
+    jdouble d2 = cp2->double_at(index2);
+    if (d1 == d2) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_Fieldref:
+  case JVM_CONSTANT_InterfaceMethodref:
+  case JVM_CONSTANT_Methodref:
+  {
+    int recur1 = uncached_klass_ref_index_at(index1);
+    int recur2 = cp2->uncached_klass_ref_index_at(index2);
+    bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
+    if (match) {
+      recur1 = uncached_name_and_type_ref_index_at(index1);
+      recur2 = cp2->uncached_name_and_type_ref_index_at(index2);
+      match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
+      if (match) {
+        return true;
+      }
+    }
+  } break;
+
+  case JVM_CONSTANT_Float:
+  {
+    jfloat f1 = float_at(index1);
+    jfloat f2 = cp2->float_at(index2);
+    if (f1 == f2) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_Integer:
+  {
+    jint i1 = int_at(index1);
+    jint i2 = cp2->int_at(index2);
+    if (i1 == i2) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_Long:
+  {
+    jlong l1 = long_at(index1);
+    jlong l2 = cp2->long_at(index2);
+    if (l1 == l2) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_NameAndType:
+  {
+    int recur1 = name_ref_index_at(index1);
+    int recur2 = cp2->name_ref_index_at(index2);
+    bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
+    if (match) {
+      recur1 = signature_ref_index_at(index1);
+      recur2 = cp2->signature_ref_index_at(index2);
+      match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
+      if (match) {
+        return true;
+      }
+    }
+  } break;
+
+  case JVM_CONSTANT_StringIndex:
+  {
+    int recur1 = string_index_at(index1);
+    int recur2 = cp2->string_index_at(index2);
+    bool match = compare_entry_to(recur1, cp2, recur2, CHECK_false);
+    if (match) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_UnresolvedClass:
+  {
+    Symbol* k1 = klass_name_at(index1);
+    Symbol* k2 = cp2->klass_name_at(index2);
+    if (k1 == k2) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_MethodType:
+  {
+    int k1 = method_type_index_at(index1);
+    int k2 = cp2->method_type_index_at(index2);
+    bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
+    if (match) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_MethodHandle:
+  {
+    int k1 = method_handle_ref_kind_at(index1);
+    int k2 = cp2->method_handle_ref_kind_at(index2);
+    if (k1 == k2) {
+      int i1 = method_handle_index_at(index1);
+      int i2 = cp2->method_handle_index_at(index2);
+      bool match = compare_entry_to(i1, cp2, i2, CHECK_false);
+      if (match) {
+        return true;
+      }
+    }
+  } break;
+
+  case JVM_CONSTANT_InvokeDynamic:
+  {
+    int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
+    int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
+    int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
+    int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
+    // separate statements and variables because CHECK_false is used
+    bool match_entry = compare_entry_to(k1, cp2, k2, CHECK_false);
+    bool match_operand = compare_operand_to(i1, cp2, i2, CHECK_false);
+    return (match_entry && match_operand);
+  } break;
+
+  case JVM_CONSTANT_String:
+  {
+    Symbol* s1 = unresolved_string_at(index1);
+    Symbol* s2 = cp2->unresolved_string_at(index2);
+    if (s1 == s2) {
+      return true;
+    }
+  } break;
+
+  case JVM_CONSTANT_Utf8:
+  {
+    Symbol* s1 = symbol_at(index1);
+    Symbol* s2 = cp2->symbol_at(index2);
+    if (s1 == s2) {
+      return true;
+    }
+  } break;
+
+  // Invalid is used as the tag for the second constant pool entry
+  // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
+  // not be seen by itself.
+  case JVM_CONSTANT_Invalid: // fall through
+
+  default:
+    ShouldNotReachHere();
+    break;
+  }
+
+  return false;
+} // end compare_entry_to()
+
+
+// Resize the operands array with delta_len and delta_size.
+// Used in RedefineClasses for CP merge.
+void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
+  int old_len  = operand_array_length(operands());
+  int new_len  = old_len + delta_len;
+  int min_len  = (delta_len > 0) ? old_len : new_len;
+
+  int old_size = operands()->length();
+  int new_size = old_size + delta_size;
+  int min_size = (delta_size > 0) ? old_size : new_size;
+
+  ClassLoaderData* loader_data = pool_holder()->class_loader_data();
+  Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
+
+  // Set index in the resized array for existing elements only
+  for (int idx = 0; idx < min_len; idx++) {
+    int offset = operand_offset_at(idx);                       // offset in original array
+    operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
+  }
+  // Copy the bootstrap specifiers only
+  Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
+                               new_ops->adr_at(2*new_len),
+                               (min_size - 2*min_len) * sizeof(u2));
+  // Explicitly deallocate old operands array.
+  // Note, it is not needed for 7u backport.
+  if ( operands() != NULL) { // the safety check
+    MetadataFactory::free_array<u2>(loader_data, operands());
+  }
+  set_operands(new_ops);
+} // end resize_operands()
+
+
+// Extend the operands array with the length and size of the ext_cp operands.
+// Used in RedefineClasses for CP merge.
+void ConstantPool::extend_operands(const constantPoolHandle& ext_cp, TRAPS) {
+  int delta_len = operand_array_length(ext_cp->operands());
+  if (delta_len == 0) {
+    return; // nothing to do
+  }
+  int delta_size = ext_cp->operands()->length();
+
+  assert(delta_len  > 0 && delta_size > 0, "extended operands array must be bigger");
+
+  if (operand_array_length(operands()) == 0) {
+    ClassLoaderData* loader_data = pool_holder()->class_loader_data();
+    Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
+    // The first element index defines the offset of second part
+    operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
+    set_operands(new_ops);
+  } else {
+    resize_operands(delta_len, delta_size, CHECK);
+  }
+
+} // end extend_operands()
+
+
+// Shrink the operands array to a smaller array with new_len length.
+// Used in RedefineClasses for CP merge.
+void ConstantPool::shrink_operands(int new_len, TRAPS) {
+  int old_len = operand_array_length(operands());
+  if (new_len == old_len) {
+    return; // nothing to do
+  }
+  assert(new_len < old_len, "shrunken operands array must be smaller");
+
+  int free_base  = operand_next_offset_at(new_len - 1);
+  int delta_len  = new_len - old_len;
+  int delta_size = 2*delta_len + free_base - operands()->length();
+
+  resize_operands(delta_len, delta_size, CHECK);
+
+} // end shrink_operands()
+
+
+void ConstantPool::copy_operands(const constantPoolHandle& from_cp,
+                                 const constantPoolHandle& to_cp,
+                                 TRAPS) {
+
+  int from_oplen = operand_array_length(from_cp->operands());
+  int old_oplen  = operand_array_length(to_cp->operands());
+  if (from_oplen != 0) {
+    ClassLoaderData* loader_data = to_cp->pool_holder()->class_loader_data();
+    // append my operands to the target's operands array
+    if (old_oplen == 0) {
+      // Can't just reuse from_cp's operand list because of deallocation issues
+      int len = from_cp->operands()->length();
+      Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, len, CHECK);
+      Copy::conjoint_memory_atomic(
+          from_cp->operands()->adr_at(0), new_ops->adr_at(0), len * sizeof(u2));
+      to_cp->set_operands(new_ops);
+    } else {
+      int old_len  = to_cp->operands()->length();
+      int from_len = from_cp->operands()->length();
+      int old_off  = old_oplen * sizeof(u2);
+      int from_off = from_oplen * sizeof(u2);
+      // Use the metaspace for the destination constant pool
+      Array<u2>* new_operands = MetadataFactory::new_array<u2>(loader_data, old_len + from_len, CHECK);
+      int fillp = 0, len = 0;
+      // first part of dest
+      Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(0),
+                                   new_operands->adr_at(fillp),
+                                   (len = old_off) * sizeof(u2));
+      fillp += len;
+      // first part of src
+      Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(0),
+                                   new_operands->adr_at(fillp),
+                                   (len = from_off) * sizeof(u2));
+      fillp += len;
+      // second part of dest
+      Copy::conjoint_memory_atomic(to_cp->operands()->adr_at(old_off),
+                                   new_operands->adr_at(fillp),
+                                   (len = old_len - old_off) * sizeof(u2));
+      fillp += len;
+      // second part of src
+      Copy::conjoint_memory_atomic(from_cp->operands()->adr_at(from_off),
+                                   new_operands->adr_at(fillp),
+                                   (len = from_len - from_off) * sizeof(u2));
+      fillp += len;
+      assert(fillp == new_operands->length(), "");
+
+      // Adjust indexes in the first part of the copied operands array.
+      for (int j = 0; j < from_oplen; j++) {
+        int offset = operand_offset_at(new_operands, old_oplen + j);
+        assert(offset == operand_offset_at(from_cp->operands(), j), "correct copy");
+        offset += old_len;  // every new tuple is preceded by old_len extra u2's
+        operand_offset_at_put(new_operands, old_oplen + j, offset);
+      }
+
+      // replace target operands array with combined array
+      to_cp->set_operands(new_operands);
+    }
+  }
+} // end copy_operands()
+
+
+// Copy this constant pool's entries at start_i to end_i (inclusive)
+// to the constant pool to_cp's entries starting at to_i. A total of
+// (end_i - start_i) + 1 entries are copied.
+void ConstantPool::copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i,
+       const constantPoolHandle& to_cp, int to_i, TRAPS) {
+
+
+  int dest_i = to_i;  // leave original alone for debug purposes
+
+  for (int src_i = start_i; src_i <= end_i; /* see loop bottom */ ) {
+    copy_entry_to(from_cp, src_i, to_cp, dest_i, CHECK);
+
+    switch (from_cp->tag_at(src_i).value()) {
+    case JVM_CONSTANT_Double:
+    case JVM_CONSTANT_Long:
+      // double and long take two constant pool entries
+      src_i += 2;
+      dest_i += 2;
+      break;
+
+    default:
+      // all others take one constant pool entry
+      src_i++;
+      dest_i++;
+      break;
+    }
+  }
+  copy_operands(from_cp, to_cp, CHECK);
+
+} // end copy_cp_to_impl()
+
+
+// Copy this constant pool's entry at from_i to the constant pool
+// to_cp's entry at to_i.
+void ConstantPool::copy_entry_to(const constantPoolHandle& from_cp, int from_i,
+                                        const constantPoolHandle& to_cp, int to_i,
+                                        TRAPS) {
+
+  int tag = from_cp->tag_at(from_i).value();
+  switch (tag) {
+  case JVM_CONSTANT_ClassIndex:
+  {
+    jint ki = from_cp->klass_index_at(from_i);
+    to_cp->klass_index_at_put(to_i, ki);
+  } break;
+
+  case JVM_CONSTANT_Double:
+  {
+    jdouble d = from_cp->double_at(from_i);
+    to_cp->double_at_put(to_i, d);
+    // double takes two constant pool entries so init second entry's tag
+    to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
+  } break;
+
+  case JVM_CONSTANT_Fieldref:
+  {
+    int class_index = from_cp->uncached_klass_ref_index_at(from_i);
+    int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
+    to_cp->field_at_put(to_i, class_index, name_and_type_index);
+  } break;
+
+  case JVM_CONSTANT_Float:
+  {
+    jfloat f = from_cp->float_at(from_i);
+    to_cp->float_at_put(to_i, f);
+  } break;
+
+  case JVM_CONSTANT_Integer:
+  {
+    jint i = from_cp->int_at(from_i);
+    to_cp->int_at_put(to_i, i);
+  } break;
+
+  case JVM_CONSTANT_InterfaceMethodref:
+  {
+    int class_index = from_cp->uncached_klass_ref_index_at(from_i);
+    int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
+    to_cp->interface_method_at_put(to_i, class_index, name_and_type_index);
+  } break;
+
+  case JVM_CONSTANT_Long:
+  {
+    jlong l = from_cp->long_at(from_i);
+    to_cp->long_at_put(to_i, l);
+    // long takes two constant pool entries so init second entry's tag
+    to_cp->tag_at_put(to_i + 1, JVM_CONSTANT_Invalid);
+  } break;
+
+  case JVM_CONSTANT_Methodref:
+  {
+    int class_index = from_cp->uncached_klass_ref_index_at(from_i);
+    int name_and_type_index = from_cp->uncached_name_and_type_ref_index_at(from_i);
+    to_cp->method_at_put(to_i, class_index, name_and_type_index);
+  } break;
+
+  case JVM_CONSTANT_NameAndType:
+  {
+    int name_ref_index = from_cp->name_ref_index_at(from_i);
+    int signature_ref_index = from_cp->signature_ref_index_at(from_i);
+    to_cp->name_and_type_at_put(to_i, name_ref_index, signature_ref_index);
+  } break;
+
+  case JVM_CONSTANT_StringIndex:
+  {
+    jint si = from_cp->string_index_at(from_i);
+    to_cp->string_index_at_put(to_i, si);
+  } break;
+
+  case JVM_CONSTANT_Class:
+  case JVM_CONSTANT_UnresolvedClass:
+  case JVM_CONSTANT_UnresolvedClassInError:
+  {
+    // Revert to JVM_CONSTANT_ClassIndex
+    int name_index = from_cp->klass_slot_at(from_i).name_index();
+    assert(from_cp->tag_at(name_index).is_symbol(), "sanity");
+    to_cp->klass_index_at_put(to_i, name_index);
+  } break;
+
+  case JVM_CONSTANT_String:
+  {
+    Symbol* s = from_cp->unresolved_string_at(from_i);
+    to_cp->unresolved_string_at_put(to_i, s);
+  } break;
+
+  case JVM_CONSTANT_Utf8:
+  {
+    Symbol* s = from_cp->symbol_at(from_i);
+    // Need to increase refcount, the old one will be thrown away and deferenced
+    s->increment_refcount();
+    to_cp->symbol_at_put(to_i, s);
+  } break;
+
+  case JVM_CONSTANT_MethodType:
+  case JVM_CONSTANT_MethodTypeInError:
+  {
+    jint k = from_cp->method_type_index_at(from_i);
+    to_cp->method_type_index_at_put(to_i, k);
+  } break;
+
+  case JVM_CONSTANT_MethodHandle:
+  case JVM_CONSTANT_MethodHandleInError:
+  {
+    int k1 = from_cp->method_handle_ref_kind_at(from_i);
+    int k2 = from_cp->method_handle_index_at(from_i);
+    to_cp->method_handle_index_at_put(to_i, k1, k2);
+  } break;
+
+  case JVM_CONSTANT_InvokeDynamic:
+  {
+    int k1 = from_cp->invoke_dynamic_bootstrap_specifier_index(from_i);
+    int k2 = from_cp->invoke_dynamic_name_and_type_ref_index_at(from_i);
+    k1 += operand_array_length(to_cp->operands());  // to_cp might already have operands
+    to_cp->invoke_dynamic_at_put(to_i, k1, k2);
+  } break;
+
+  // Invalid is used as the tag for the second constant pool entry
+  // occupied by JVM_CONSTANT_Double or JVM_CONSTANT_Long. It should
+  // not be seen by itself.
+  case JVM_CONSTANT_Invalid: // fall through
+
+  default:
+  {
+    ShouldNotReachHere();
+  } break;
+  }
+} // end copy_entry_to()
+
+// Search constant pool search_cp for an entry that matches this
+// constant pool's entry at pattern_i. Returns the index of a
+// matching entry or zero (0) if there is no matching entry.
+int ConstantPool::find_matching_entry(int pattern_i,
+      const constantPoolHandle& search_cp, TRAPS) {
+
+  // index zero (0) is not used
+  for (int i = 1; i < search_cp->length(); i++) {
+    bool found = compare_entry_to(pattern_i, search_cp, i, CHECK_0);
+    if (found) {
+      return i;
+    }
+  }
+
+  return 0;  // entry not found; return unused index zero (0)
+} // end find_matching_entry()
+
+
+// Compare this constant pool's bootstrap specifier at idx1 to the constant pool
+// cp2's bootstrap specifier at idx2.
+bool ConstantPool::compare_operand_to(int idx1, const constantPoolHandle& cp2, int idx2, TRAPS) {
+  int k1 = operand_bootstrap_method_ref_index_at(idx1);
+  int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
+  bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
+
+  if (!match) {
+    return false;
+  }
+  int argc = operand_argument_count_at(idx1);
+  if (argc == cp2->operand_argument_count_at(idx2)) {
+    for (int j = 0; j < argc; j++) {
+      k1 = operand_argument_index_at(idx1, j);
+      k2 = cp2->operand_argument_index_at(idx2, j);
+      match = compare_entry_to(k1, cp2, k2, CHECK_false);
+      if (!match) {
+        return false;
+      }
+    }
+    return true;           // got through loop; all elements equal
+  }
+  return false;
+} // end compare_operand_to()
+
+// Search constant pool search_cp for a bootstrap specifier that matches
+// this constant pool's bootstrap specifier at pattern_i index.
+// Return the index of a matching bootstrap specifier or (-1) if there is no match.
+int ConstantPool::find_matching_operand(int pattern_i,
+                    const constantPoolHandle& search_cp, int search_len, TRAPS) {
+  for (int i = 0; i < search_len; i++) {
+    bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
+    if (found) {
+      return i;
+    }
+  }
+  return -1;  // bootstrap specifier not found; return unused index (-1)
+} // end find_matching_operand()
+
+
+#ifndef PRODUCT
+
+const char* ConstantPool::printable_name_at(int which) {
+
+  constantTag tag = tag_at(which);
+
+  if (tag.is_string()) {
+    return string_at_noresolve(which);
+  } else if (tag.is_klass() || tag.is_unresolved_klass()) {
+    return klass_name_at(which)->as_C_string();
+  } else if (tag.is_symbol()) {
+    return symbol_at(which)->as_C_string();
+  }
+  return "";
+}
+
+#endif // PRODUCT
+
+
+// JVMTI GetConstantPool support
+
+// For debugging of constant pool
+const bool debug_cpool = false;
+
+#define DBG(code) do { if (debug_cpool) { (code); } } while(0)
+
+static void print_cpool_bytes(jint cnt, u1 *bytes) {
+  const char* WARN_MSG = "Must not be such entry!";
+  jint size = 0;
+  u2   idx1, idx2;
+
+  for (jint idx = 1; idx < cnt; idx++) {
+    jint ent_size = 0;
+    u1   tag  = *bytes++;
+    size++;                       // count tag
+
+    printf("const #%03d, tag: %02d ", idx, tag);
+    switch(tag) {
+      case JVM_CONSTANT_Invalid: {
+        printf("Invalid");
+        break;
+      }
+      case JVM_CONSTANT_Unicode: {
+        printf("Unicode      %s", WARN_MSG);
+        break;
+      }
+      case JVM_CONSTANT_Utf8: {
+        u2 len = Bytes::get_Java_u2(bytes);
+        char str[128];
+        if (len > 127) {
+           len = 127;
+        }
+        strncpy(str, (char *) (bytes+2), len);
+        str[len] = '\0';
+        printf("Utf8          \"%s\"", str);
+        ent_size = 2 + len;
+        break;
+      }
+      case JVM_CONSTANT_Integer: {
+        u4 val = Bytes::get_Java_u4(bytes);
+        printf("int          %d", *(int *) &val);
+        ent_size = 4;
+        break;
+      }
+      case JVM_CONSTANT_Float: {
+        u4 val = Bytes::get_Java_u4(bytes);
+        printf("float        %5.3ff", *(float *) &val);
+        ent_size = 4;
+        break;
+      }
+      case JVM_CONSTANT_Long: {
+        u8 val = Bytes::get_Java_u8(bytes);
+        printf("long         " INT64_FORMAT, (int64_t) *(jlong *) &val);
+        ent_size = 8;
+        idx++; // Long takes two cpool slots
+        break;
+      }
+      case JVM_CONSTANT_Double: {
+        u8 val = Bytes::get_Java_u8(bytes);
+        printf("double       %5.3fd", *(jdouble *)&val);
+        ent_size = 8;
+        idx++; // Double takes two cpool slots
+        break;
+      }
+      case JVM_CONSTANT_Class: {
+        idx1 = Bytes::get_Java_u2(bytes);
+        printf("class        #%03d", idx1);
+        ent_size = 2;
+        break;
+      }
+      case JVM_CONSTANT_String: {
+        idx1 = Bytes::get_Java_u2(bytes);
+        printf("String       #%03d", idx1);
+        ent_size = 2;
+        break;
+      }
+      case JVM_CONSTANT_Fieldref: {
+        idx1 = Bytes::get_Java_u2(bytes);
+        idx2 = Bytes::get_Java_u2(bytes+2);
+        printf("Field        #%03d, #%03d", (int) idx1, (int) idx2);
+        ent_size = 4;
+        break;
+      }
+      case JVM_CONSTANT_Methodref: {
+        idx1 = Bytes::get_Java_u2(bytes);
+        idx2 = Bytes::get_Java_u2(bytes+2);
+        printf("Method       #%03d, #%03d", idx1, idx2);
+        ent_size = 4;
+        break;
+      }
+      case JVM_CONSTANT_InterfaceMethodref: {
+        idx1 = Bytes::get_Java_u2(bytes);
+        idx2 = Bytes::get_Java_u2(bytes+2);
+        printf("InterfMethod #%03d, #%03d", idx1, idx2);
+        ent_size = 4;
+        break;
+      }
+      case JVM_CONSTANT_NameAndType: {
+        idx1 = Bytes::get_Java_u2(bytes);
+        idx2 = Bytes::get_Java_u2(bytes+2);
+        printf("NameAndType  #%03d, #%03d", idx1, idx2);
+        ent_size = 4;
+        break;
+      }
+      case JVM_CONSTANT_ClassIndex: {
+        printf("ClassIndex  %s", WARN_MSG);
+        break;
+      }
+      case JVM_CONSTANT_UnresolvedClass: {
+        printf("UnresolvedClass: %s", WARN_MSG);
+        break;
+      }
+      case JVM_CONSTANT_UnresolvedClassInError: {
+        printf("UnresolvedClassInErr: %s", WARN_MSG);
+        break;
+      }
+      case JVM_CONSTANT_StringIndex: {
+        printf("StringIndex: %s", WARN_MSG);
+        break;
+      }
+    }
+    printf(";\n");
+    bytes += ent_size;
+    size  += ent_size;
+  }
+  printf("Cpool size: %d\n", size);
+  fflush(0);
+  return;
+} /* end print_cpool_bytes */
+
+
+// Returns size of constant pool entry.
+jint ConstantPool::cpool_entry_size(jint idx) {
+  switch(tag_at(idx).value()) {
+    case JVM_CONSTANT_Invalid:
+    case JVM_CONSTANT_Unicode:
+      return 1;
+
+    case JVM_CONSTANT_Utf8:
+      return 3 + symbol_at(idx)->utf8_length();
+
+    case JVM_CONSTANT_Class:
+    case JVM_CONSTANT_String:
+    case JVM_CONSTANT_ClassIndex:
+    case JVM_CONSTANT_UnresolvedClass:
+    case JVM_CONSTANT_UnresolvedClassInError:
+    case JVM_CONSTANT_StringIndex:
+    case JVM_CONSTANT_MethodType:
+    case JVM_CONSTANT_MethodTypeInError:
+      return 3;
+
+    case JVM_CONSTANT_MethodHandle:
+    case JVM_CONSTANT_MethodHandleInError:
+      return 4; //tag, ref_kind, ref_index
+
+    case JVM_CONSTANT_Integer:
+    case JVM_CONSTANT_Float:
+    case JVM_CONSTANT_Fieldref:
+    case JVM_CONSTANT_Methodref:
+    case JVM_CONSTANT_InterfaceMethodref:
+    case JVM_CONSTANT_NameAndType:
+      return 5;
+
+    case JVM_CONSTANT_InvokeDynamic:
+      // u1 tag, u2 bsm, u2 nt
+      return 5;
+
+    case JVM_CONSTANT_Long:
+    case JVM_CONSTANT_Double:
+      return 9;
+  }
+  assert(false, "cpool_entry_size: Invalid constant pool entry tag");
+  return 1;
+} /* end cpool_entry_size */
+
+
+// SymbolHashMap is used to find a constant pool index from a string.
+// This function fills in SymbolHashMaps, one for utf8s and one for
+// class names, returns size of the cpool raw bytes.
+jint ConstantPool::hash_entries_to(SymbolHashMap *symmap,
+                                          SymbolHashMap *classmap) {
+  jint size = 0;
+
+  for (u2 idx = 1; idx < length(); idx++) {
+    u2 tag = tag_at(idx).value();
+    size += cpool_entry_size(idx);
+
+    switch(tag) {
+      case JVM_CONSTANT_Utf8: {
+        Symbol* sym = symbol_at(idx);
+        symmap->add_entry(sym, idx);
+        DBG(printf("adding symbol entry %s = %d\n", sym->as_utf8(), idx));
+        break;
+      }
+      case JVM_CONSTANT_Class:
+      case JVM_CONSTANT_UnresolvedClass:
+      case JVM_CONSTANT_UnresolvedClassInError: {
+        Symbol* sym = klass_name_at(idx);
+        classmap->add_entry(sym, idx);
+        DBG(printf("adding class entry %s = %d\n", sym->as_utf8(), idx));
+        break;
+      }
+      case JVM_CONSTANT_Long:
+      case JVM_CONSTANT_Double: {
+        idx++; // Both Long and Double take two cpool slots
+        break;
+      }
+    }
+  }
+  return size;
+} /* end hash_utf8_entries_to */
+
+
+// Copy cpool bytes.
+// Returns:
+//    0, in case of OutOfMemoryError
+//   -1, in case of internal error
+//  > 0, count of the raw cpool bytes that have been copied
+int ConstantPool::copy_cpool_bytes(int cpool_size,
+                                          SymbolHashMap* tbl,
+                                          unsigned char *bytes) {
+  u2   idx1, idx2;
+  jint size  = 0;
+  jint cnt   = length();
+  unsigned char *start_bytes = bytes;
+
+  for (jint idx = 1; idx < cnt; idx++) {
+    u1   tag      = tag_at(idx).value();
+    jint ent_size = cpool_entry_size(idx);
+
+    assert(size + ent_size <= cpool_size, "Size mismatch");
+
+    *bytes = tag;
+    DBG(printf("#%03hd tag=%03hd, ", (short)idx, (short)tag));
+    switch(tag) {
+      case JVM_CONSTANT_Invalid: {
+        DBG(printf("JVM_CONSTANT_Invalid"));
+        break;
+      }
+      case JVM_CONSTANT_Unicode: {
+        assert(false, "Wrong constant pool tag: JVM_CONSTANT_Unicode");
+        DBG(printf("JVM_CONSTANT_Unicode"));
+        break;
+      }
+      case JVM_CONSTANT_Utf8: {
+        Symbol* sym = symbol_at(idx);
+        char*     str = sym->as_utf8();
+        // Warning! It's crashing on x86 with len = sym->utf8_length()
+        int       len = (int) strlen(str);
+        Bytes::put_Java_u2((address) (bytes+1), (u2) len);
+        for (int i = 0; i < len; i++) {
+            bytes[3+i] = (u1) str[i];
+        }
+        DBG(printf("JVM_CONSTANT_Utf8: %s ", str));
+        break;
+      }
+      case JVM_CONSTANT_Integer: {
+        jint val = int_at(idx);
+        Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
+        break;
+      }
+      case JVM_CONSTANT_Float: {
+        jfloat val = float_at(idx);
+        Bytes::put_Java_u4((address) (bytes+1), *(u4*)&val);
+        break;
+      }
+      case JVM_CONSTANT_Long: {
+        jlong val = long_at(idx);
+        Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
+        idx++;             // Long takes two cpool slots
+        break;
+      }
+      case JVM_CONSTANT_Double: {
+        jdouble val = double_at(idx);
+        Bytes::put_Java_u8((address) (bytes+1), *(u8*)&val);
+        idx++;             // Double takes two cpool slots
+        break;
+      }
+      case JVM_CONSTANT_Class:
+      case JVM_CONSTANT_UnresolvedClass:
+      case JVM_CONSTANT_UnresolvedClassInError: {
+        *bytes = JVM_CONSTANT_Class;
+        Symbol* sym = klass_name_at(idx);
+        idx1 = tbl->symbol_to_value(sym);
+        assert(idx1 != 0, "Have not found a hashtable entry");
+        Bytes::put_Java_u2((address) (bytes+1), idx1);
+        DBG(printf("JVM_CONSTANT_Class: idx=#%03hd, %s", idx1, sym->as_utf8()));
+        break;
+      }
+      case JVM_CONSTANT_String: {
+        *bytes = JVM_CONSTANT_String;
+        Symbol* sym = unresolved_string_at(idx);
+        idx1 = tbl->symbol_to_value(sym);
+        assert(idx1 != 0, "Have not found a hashtable entry");
+        Bytes::put_Java_u2((address) (bytes+1), idx1);
+        DBG(printf("JVM_CONSTANT_String: idx=#%03hd, %s", idx1, sym->as_utf8()));
+        break;
+      }
+      case JVM_CONSTANT_Fieldref:
+      case JVM_CONSTANT_Methodref:
+      case JVM_CONSTANT_InterfaceMethodref: {
+        idx1 = uncached_klass_ref_index_at(idx);
+        idx2 = uncached_name_and_type_ref_index_at(idx);
+        Bytes::put_Java_u2((address) (bytes+1), idx1);
+        Bytes::put_Java_u2((address) (bytes+3), idx2);
+        DBG(printf("JVM_CONSTANT_Methodref: %hd %hd", idx1, idx2));
+        break;
+      }
+      case JVM_CONSTANT_NameAndType: {
+        idx1 = name_ref_index_at(idx);
+        idx2 = signature_ref_index_at(idx);
+        Bytes::put_Java_u2((address) (bytes+1), idx1);
+        Bytes::put_Java_u2((address) (bytes+3), idx2);
+        DBG(printf("JVM_CONSTANT_NameAndType: %hd %hd", idx1, idx2));
+        break;
+      }
+      case JVM_CONSTANT_ClassIndex: {
+        *bytes = JVM_CONSTANT_Class;
+        idx1 = klass_index_at(idx);
+        Bytes::put_Java_u2((address) (bytes+1), idx1);
+        DBG(printf("JVM_CONSTANT_ClassIndex: %hd", idx1));
+        break;
+      }
+      case JVM_CONSTANT_StringIndex: {
+        *bytes = JVM_CONSTANT_String;
+        idx1 = string_index_at(idx);
+        Bytes::put_Java_u2((address) (bytes+1), idx1);
+        DBG(printf("JVM_CONSTANT_StringIndex: %hd", idx1));
+        break;
+      }
+      case JVM_CONSTANT_MethodHandle:
+      case JVM_CONSTANT_MethodHandleInError: {
+        *bytes = JVM_CONSTANT_MethodHandle;
+        int kind = method_handle_ref_kind_at(idx);
+        idx1 = method_handle_index_at(idx);
+        *(bytes+1) = (unsigned char) kind;
+        Bytes::put_Java_u2((address) (bytes+2), idx1);
+        DBG(printf("JVM_CONSTANT_MethodHandle: %d %hd", kind, idx1));
+        break;
+      }
+      case JVM_CONSTANT_MethodType:
+      case JVM_CONSTANT_MethodTypeInError: {
+        *bytes = JVM_CONSTANT_MethodType;
+        idx1 = method_type_index_at(idx);
+        Bytes::put_Java_u2((address) (bytes+1), idx1);
+        DBG(printf("JVM_CONSTANT_MethodType: %hd", idx1));
+        break;
+      }
+      case JVM_CONSTANT_InvokeDynamic: {
+        *bytes = tag;
+        idx1 = extract_low_short_from_int(*int_at_addr(idx));
+        idx2 = extract_high_short_from_int(*int_at_addr(idx));
+        assert(idx2 == invoke_dynamic_name_and_type_ref_index_at(idx), "correct half of u4");
+        Bytes::put_Java_u2((address) (bytes+1), idx1);
+        Bytes::put_Java_u2((address) (bytes+3), idx2);
+        DBG(printf("JVM_CONSTANT_InvokeDynamic: %hd %hd", idx1, idx2));
+        break;
+      }
+    }
+    DBG(printf("\n"));
+    bytes += ent_size;
+    size  += ent_size;
+  }
+  assert(size == cpool_size, "Size mismatch");
+
+  // Keep temorarily for debugging until it's stable.
+  DBG(print_cpool_bytes(cnt, start_bytes));
+  return (int)(bytes - start_bytes);
+} /* end copy_cpool_bytes */
+
+#undef DBG
+
+
+void ConstantPool::set_on_stack(const bool value) {
+  if (value) {
+    // Only record if it's not already set.
+    if (!on_stack()) {
+      assert(!is_shared(), "should always be set for shared constant pools");
+      _flags |= _on_stack;
+      MetadataOnStackMark::record(this);
+    }
+  } else {
+    // Clearing is done single-threadedly.
+    if (!is_shared()) {
+      _flags &= ~_on_stack;
+    }
+  }
+}
+
+// JSR 292 support for patching constant pool oops after the class is linked and
+// the oop array for resolved references are created.
+// We can't do this during classfile parsing, which is how the other indexes are
+// patched.  The other patches are applied early for some error checking
+// so only defer the pseudo_strings.
+void ConstantPool::patch_resolved_references(GrowableArray<Handle>* cp_patches) {
+  for (int index = 1; index < cp_patches->length(); index++) { // Index 0 is unused
+    Handle patch = cp_patches->at(index);
+    if (patch.not_null()) {
+      assert (tag_at(index).is_string(), "should only be string left");
+      // Patching a string means pre-resolving it.
+      // The spelling in the constant pool is ignored.
+      // The constant reference may be any object whatever.
+      // If it is not a real interned string, the constant is referred
+      // to as a "pseudo-string", and must be presented to the CP
+      // explicitly, because it may require scavenging.
+      int obj_index = cp_to_object_index(index);
+      pseudo_string_at_put(index, obj_index, patch());
+     DEBUG_ONLY(cp_patches->at_put(index, Handle());)
+    }
+  }
+#ifdef ASSERT
+  // Ensure that all the patches have been used.
+  for (int index = 0; index < cp_patches->length(); index++) {
+    assert(cp_patches->at(index).is_null(),
+           "Unused constant pool patch at %d in class file %s",
+           index,
+           pool_holder()->external_name());
+  }
+#endif // ASSERT
+}
+
+#ifndef PRODUCT
+
+// CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
+void ConstantPool::preload_and_initialize_all_classes(ConstantPool* obj, TRAPS) {
+  guarantee(obj->is_constantPool(), "object must be constant pool");
+  constantPoolHandle cp(THREAD, (ConstantPool*)obj);
+  guarantee(cp->pool_holder() != NULL, "must be fully loaded");
+
+  for (int i = 0; i< cp->length();  i++) {
+    if (cp->tag_at(i).is_unresolved_klass()) {
+      // This will force loading of the class
+      Klass* klass = cp->klass_at(i, CHECK);
+      if (klass->is_instance_klass()) {
+        // Force initialization of class
+        InstanceKlass::cast(klass)->initialize(CHECK);
+      }
+    }
+  }
+}
+
+#endif
+
+
+// Printing
+
+void ConstantPool::print_on(outputStream* st) const {
+  assert(is_constantPool(), "must be constantPool");
+  st->print_cr("%s", internal_name());
+  if (flags() != 0) {
+    st->print(" - flags: 0x%x", flags());
+    if (has_preresolution()) st->print(" has_preresolution");
+    if (on_stack()) st->print(" on_stack");
+    st->cr();
+  }
+  if (pool_holder() != NULL) {
+    st->print_cr(" - holder: " INTPTR_FORMAT, p2i(pool_holder()));
+  }
+  st->print_cr(" - cache: " INTPTR_FORMAT, p2i(cache()));
+  st->print_cr(" - resolved_references: " INTPTR_FORMAT, p2i(resolved_references()));
+  st->print_cr(" - reference_map: " INTPTR_FORMAT, p2i(reference_map()));
+  st->print_cr(" - resolved_klasses: " INTPTR_FORMAT, p2i(resolved_klasses()));
+
+  for (int index = 1; index < length(); index++) {      // Index 0 is unused
+    ((ConstantPool*)this)->print_entry_on(index, st);
+    switch (tag_at(index).value()) {
+      case JVM_CONSTANT_Long :
+      case JVM_CONSTANT_Double :
+        index++;   // Skip entry following eigth-byte constant
+    }
+
+  }
+  st->cr();
+}
+
+// Print one constant pool entry
+void ConstantPool::print_entry_on(const int index, outputStream* st) {
+  EXCEPTION_MARK;
+  st->print(" - %3d : ", index);
+  tag_at(index).print_on(st);
+  st->print(" : ");
+  switch (tag_at(index).value()) {
+    case JVM_CONSTANT_Class :
+      { Klass* k = klass_at(index, CATCH);
+        guarantee(k != NULL, "need klass");
+        k->print_value_on(st);
+        st->print(" {" PTR_FORMAT "}", p2i(k));
+      }
+      break;
+    case JVM_CONSTANT_Fieldref :
+    case JVM_CONSTANT_Methodref :
+    case JVM_CONSTANT_InterfaceMethodref :
+      st->print("klass_index=%d", uncached_klass_ref_index_at(index));
+      st->print(" name_and_type_index=%d", uncached_name_and_type_ref_index_at(index));
+      break;
+    case JVM_CONSTANT_String :
+      if (is_pseudo_string_at(index)) {
+        oop anObj = pseudo_string_at(index);
+        anObj->print_value_on(st);
+        st->print(" {" PTR_FORMAT "}", p2i(anObj));
+      } else {
+        unresolved_string_at(index)->print_value_on(st);
+      }
+      break;
+    case JVM_CONSTANT_Integer :
+      st->print("%d", int_at(index));
+      break;
+    case JVM_CONSTANT_Float :
+      st->print("%f", float_at(index));
+      break;
+    case JVM_CONSTANT_Long :
+      st->print_jlong(long_at(index));
+      break;
+    case JVM_CONSTANT_Double :
+      st->print("%lf", double_at(index));
+      break;
+    case JVM_CONSTANT_NameAndType :
+      st->print("name_index=%d", name_ref_index_at(index));
+      st->print(" signature_index=%d", signature_ref_index_at(index));
+      break;
+    case JVM_CONSTANT_Utf8 :
+      symbol_at(index)->print_value_on(st);
+      break;
+    case JVM_CONSTANT_ClassIndex: {
+        int name_index = *int_at_addr(index);
+        st->print("klass_index=%d ", name_index);
+        symbol_at(name_index)->print_value_on(st);
+      }
+      break;
+    case JVM_CONSTANT_UnresolvedClass :               // fall-through
+    case JVM_CONSTANT_UnresolvedClassInError: {
+        CPKlassSlot kslot = klass_slot_at(index);
+        int resolved_klass_index = kslot.resolved_klass_index();
+        int name_index = kslot.name_index();
+        assert(tag_at(name_index).is_symbol(), "sanity");
+
+        Klass* klass = resolved_klasses()->at(resolved_klass_index);
+        if (klass != NULL) {
+          klass->print_value_on(st);
+        } else {
+          symbol_at(name_index)->print_value_on(st);
+        }
+      }
+      break;
+    case JVM_CONSTANT_MethodHandle :
+    case JVM_CONSTANT_MethodHandleInError :
+      st->print("ref_kind=%d", method_handle_ref_kind_at(index));
+      st->print(" ref_index=%d", method_handle_index_at(index));
+      break;
+    case JVM_CONSTANT_MethodType :
+    case JVM_CONSTANT_MethodTypeInError :
+      st->print("signature_index=%d", method_type_index_at(index));
+      break;
+    case JVM_CONSTANT_InvokeDynamic :
+      {
+        st->print("bootstrap_method_index=%d", invoke_dynamic_bootstrap_method_ref_index_at(index));
+        st->print(" name_and_type_index=%d", invoke_dynamic_name_and_type_ref_index_at(index));
+        int argc = invoke_dynamic_argument_count_at(index);
+        if (argc > 0) {
+          for (int arg_i = 0; arg_i < argc; arg_i++) {
+            int arg = invoke_dynamic_argument_index_at(index, arg_i);
+            st->print((arg_i == 0 ? " arguments={%d" : ", %d"), arg);
+          }
+          st->print("}");
+        }
+      }
+      break;
+    default:
+      ShouldNotReachHere();
+      break;
+  }
+  st->cr();
+}
+
+void ConstantPool::print_value_on(outputStream* st) const {
+  assert(is_constantPool(), "must be constantPool");
+  st->print("constant pool [%d]", length());
+  if (has_preresolution()) st->print("/preresolution");
+  if (operands() != NULL)  st->print("/operands[%d]", operands()->length());
+  print_address_on(st);
+  st->print(" for ");
+  pool_holder()->print_value_on(st);
+  if (pool_holder() != NULL) {
+    bool extra = (pool_holder()->constants() != this);
+    if (extra)  st->print(" (extra)");
+  }
+  if (cache() != NULL) {
+    st->print(" cache=" PTR_FORMAT, p2i(cache()));
+  }
+}
+
+#if INCLUDE_SERVICES
+// Size Statistics
+void ConstantPool::collect_statistics(KlassSizeStats *sz) const {
+  sz->_cp_all_bytes += (sz->_cp_bytes          = sz->count(this));
+  sz->_cp_all_bytes += (sz->_cp_tags_bytes     = sz->count_array(tags()));
+  sz->_cp_all_bytes += (sz->_cp_cache_bytes    = sz->count(cache()));
+  sz->_cp_all_bytes += (sz->_cp_operands_bytes = sz->count_array(operands()));
+  sz->_cp_all_bytes += (sz->_cp_refmap_bytes   = sz->count_array(reference_map()));
+
+  sz->_ro_bytes += sz->_cp_operands_bytes + sz->_cp_tags_bytes +
+                   sz->_cp_refmap_bytes;
+  sz->_rw_bytes += sz->_cp_bytes + sz->_cp_cache_bytes;
+}
+#endif // INCLUDE_SERVICES
+
+// Verification
+
+void ConstantPool::verify_on(outputStream* st) {
+  guarantee(is_constantPool(), "object must be constant pool");
+  for (int i = 0; i< length();  i++) {
+    constantTag tag = tag_at(i);
+    if (tag.is_klass() || tag.is_unresolved_klass()) {
+      guarantee(klass_name_at(i)->refcount() != 0, "should have nonzero reference count");
+    } else if (tag.is_symbol()) {
+      CPSlot entry = slot_at(i);
+      guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
+    } else if (tag.is_string()) {
+      CPSlot entry = slot_at(i);
+      guarantee(entry.get_symbol()->refcount() != 0, "should have nonzero reference count");
+    }
+  }
+  if (cache() != NULL) {
+    // Note: cache() can be NULL before a class is completely setup or
+    // in temporary constant pools used during constant pool merging
+    guarantee(cache()->is_constantPoolCache(), "should be constant pool cache");
+  }
+  if (pool_holder() != NULL) {
+    // Note: pool_holder() can be NULL in temporary constant pools
+    // used during constant pool merging
+    guarantee(pool_holder()->is_klass(),    "should be klass");
+  }
+}
+
+
+void SymbolHashMap::add_entry(Symbol* sym, u2 value) {
+  char *str = sym->as_utf8();
+  unsigned int hash = compute_hash(str, sym->utf8_length());
+  unsigned int index = hash % table_size();
+
+  // check if already in map
+  // we prefer the first entry since it is more likely to be what was used in
+  // the class file
+  for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
+    assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
+    if (en->hash() == hash && en->symbol() == sym) {
+        return;  // already there
+    }
+  }
+
+  SymbolHashMapEntry* entry = new SymbolHashMapEntry(hash, sym, value);
+  entry->set_next(bucket(index));
+  _buckets[index].set_entry(entry);
+  assert(entry->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
+}
+
+SymbolHashMapEntry* SymbolHashMap::find_entry(Symbol* sym) {
+  assert(sym != NULL, "SymbolHashMap::find_entry - symbol is NULL");
+  char *str = sym->as_utf8();
+  int   len = sym->utf8_length();
+  unsigned int hash = SymbolHashMap::compute_hash(str, len);
+  unsigned int index = hash % table_size();
+  for (SymbolHashMapEntry *en = bucket(index); en != NULL; en = en->next()) {
+    assert(en->symbol() != NULL, "SymbolHashMapEntry symbol is NULL");
+    if (en->hash() == hash && en->symbol() == sym) {
+      return en;
+    }
+  }
+  return NULL;
+}