Mercurial > hg > graal-compiler

changeset 10153:3c9b7ef92c61

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Merge
author dcubed
date Fri, 26 Apr 2013 08:40:24 -0700
parents 57ac6a688ae6 (current diff) c115fac239eb (diff)
children d1644a010f52 f258c5828eb8 9f96b7a853bc
files
diffstat 15 files changed, 492 insertions(+), 111 deletions(-) [+]
line wrap: on
line diff
--- a/src/share/vm/ci/ciEnv.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/ci/ciEnv.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -483,7 +483,8 @@
     {
       // We have to lock the cpool to keep the oop from being resolved
       // while we are accessing it.
-        MonitorLockerEx ml(cpool->lock());
+      oop cplock = cpool->lock();
+      ObjectLocker ol(cplock, THREAD, cplock != NULL);
       constantTag tag = cpool->tag_at(index);
       if (tag.is_klass()) {
         // The klass has been inserted into the constant pool
--- a/src/share/vm/classfile/classFileParser.hpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/classfile/classFileParser.hpp	Fri Apr 26 08:40:24 2013 -0700
@@ -304,7 +304,19 @@
 
   inline void assert_property(bool b, const char* msg, TRAPS) {
 #ifdef ASSERT
-    if (!b) { fatal(msg); }
+    if (!b) {
+      ResourceMark rm(THREAD);
+      fatal(err_msg(msg, _class_name->as_C_string()));
+    }
+#endif
+  }
+
+  inline void assert_property(bool b, const char* msg, int index, TRAPS) {
+#ifdef ASSERT
+    if (!b) {
+      ResourceMark rm(THREAD);
+      fatal(err_msg(msg, index, _class_name->as_C_string()));
+    }
 #endif
   }
 
@@ -312,7 +324,7 @@
     if (_need_verify) {
       guarantee_property(property, msg, index, CHECK);
     } else {
-      assert_property(property, msg, CHECK);
+      assert_property(property, msg, index, CHECK);
     }
   }
 
--- a/src/share/vm/classfile/classLoaderData.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/classfile/classLoaderData.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -277,6 +277,9 @@
 void ClassLoaderData::unload() {
   _unloading = true;
 
+  // Tell serviceability tools these classes are unloading
+  classes_do(InstanceKlass::notify_unload_class);
+
   if (TraceClassLoaderData) {
     ResourceMark rm;
     tty->print("[ClassLoaderData: unload loader data "PTR_FORMAT, this);
@@ -300,6 +303,9 @@
 
 
 ClassLoaderData::~ClassLoaderData() {
+  // Release C heap structures for all the classes.
+  classes_do(InstanceKlass::release_C_heap_structures);
+
   Metaspace *m = _metaspace;
   if (m != NULL) {
     _metaspace = NULL;
--- a/src/share/vm/classfile/dictionary.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/classfile/dictionary.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -27,7 +27,6 @@
 #include "classfile/systemDictionary.hpp"
 #include "oops/oop.inline.hpp"
 #include "prims/jvmtiRedefineClassesTrace.hpp"
-#include "services/classLoadingService.hpp"
 #include "utilities/hashtable.inline.hpp"
 
 
@@ -156,19 +155,7 @@
           if (k_def_class_loader_data == loader_data) {
             // This is the defining entry, so the referred class is about
             // to be unloaded.
-            // Notify the debugger and clean up the class.
             class_was_unloaded = true;
-            // notify the debugger
-            if (JvmtiExport::should_post_class_unload()) {
-              JvmtiExport::post_class_unload(ik);
-            }
-
-            // notify ClassLoadingService of class unload
-            ClassLoadingService::notify_class_unloaded(ik);
-
-            // Clean up C heap
-            ik->release_C_heap_structures();
-            ik->constants()->release_C_heap_structures();
           }
           // Also remove this system dictionary entry.
           purge_entry = true;
--- a/src/share/vm/oops/constantPool.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/oops/constantPool.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -40,6 +40,7 @@
 #include "runtime/init.hpp"
 #include "runtime/javaCalls.hpp"
 #include "runtime/signature.hpp"
+#include "runtime/synchronizer.hpp"
 #include "runtime/vframe.hpp"
 
 ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {
@@ -69,7 +70,6 @@
 
   // only set to non-zero if constant pool is merged by RedefineClasses
   set_version(0);
-  set_lock(new Monitor(Monitor::nonleaf + 2, "A constant pool lock"));
 
   // initialize tag array
   int length = tags->length();
@@ -95,9 +95,6 @@
 void ConstantPool::release_C_heap_structures() {
   // walk constant pool and decrement symbol reference counts
   unreference_symbols();
-
-  delete _lock;
-  set_lock(NULL);
 }
 
 objArrayOop ConstantPool::resolved_references() const {
@@ -154,9 +151,6 @@
       ClassLoaderData* loader_data = pool_holder()->class_loader_data();
       set_resolved_references(loader_data->add_handle(refs_handle));
     }
-
-    // Also need to recreate the mutex.  Make sure this matches the constructor
-    set_lock(new Monitor(Monitor::nonleaf + 2, "A constant pool lock"));
   }
 }
 
@@ -167,7 +161,23 @@
   set_resolved_reference_length(
     resolved_references() != NULL ? resolved_references()->length() : 0);
   set_resolved_references(NULL);
-  set_lock(NULL);
+}
+
+oop ConstantPool::lock() {
+  if (_pool_holder) {
+    // We re-use the _pool_holder's init_lock to reduce footprint.
+    // Notes on deadlocks:
+    // [1] This lock is a Java oop, so it can be recursively locked by
+    //     the same thread without self-deadlocks.
+    // [2] Deadlock will happen if there is circular dependency between
+    //     the <clinit> of two Java classes. However, in this case,
+    //     the deadlock would have happened long before we reach
+    //     ConstantPool::lock(), so reusing init_lock does not
+    //     increase the possibility of deadlock.
+    return _pool_holder->init_lock();
+  } else {
+    return NULL;
+  }
 }
 
 int ConstantPool::cp_to_object_index(int cp_index) {
@@ -208,7 +218,9 @@
 
   Symbol* name = NULL;
   Handle       loader;
-  {  MonitorLockerEx ml(this_oop->lock());
+  {
+    oop cplock = this_oop->lock();
+    ObjectLocker ol(cplock , THREAD, cplock != NULL);
 
     if (this_oop->tag_at(which).is_unresolved_klass()) {
       if (this_oop->tag_at(which).is_unresolved_klass_in_error()) {
@@ -255,7 +267,8 @@
 
       bool throw_orig_error = false;
       {
-        MonitorLockerEx ml(this_oop->lock());
+        oop cplock = this_oop->lock();
+        ObjectLocker ol(cplock, THREAD, cplock != NULL);
 
         // some other thread has beaten us and has resolved the class.
         if (this_oop->tag_at(which).is_klass()) {
@@ -323,7 +336,8 @@
       }
       return k();
     } else {
-      MonitorLockerEx ml(this_oop->lock());
+      oop cplock = this_oop->lock();
+      ObjectLocker ol(cplock, THREAD, cplock != NULL);
       // Only updated constant pool - if it is resolved.
       do_resolve = this_oop->tag_at(which).is_unresolved_klass();
       if (do_resolve) {
@@ -619,7 +633,8 @@
                                      int tag, TRAPS) {
   ResourceMark rm;
   Symbol* error = PENDING_EXCEPTION->klass()->name();
-  MonitorLockerEx ml(this_oop->lock());  // lock cpool to change tag.
+  oop cplock = this_oop->lock();
+  ObjectLocker ol(cplock, THREAD, cplock != NULL);  // lock cpool to change tag.
 
   int error_tag = (tag == JVM_CONSTANT_MethodHandle) ?
            JVM_CONSTANT_MethodHandleInError : JVM_CONSTANT_MethodTypeInError;
@@ -780,7 +795,8 @@
   if (cache_index >= 0) {
     // Cache the oop here also.
     Handle result_handle(THREAD, result_oop);
-    MonitorLockerEx ml(this_oop->lock());  // don't know if we really need this
+    oop cplock = this_oop->lock();
+    ObjectLocker ol(cplock, THREAD, cplock != NULL);  // don't know if we really need this
     oop result = this_oop->resolved_references()->obj_at(cache_index);
     // Benign race condition:  resolved_references may already be filled in while we were trying to lock.
     // The important thing here is that all threads pick up the same result.
@@ -1043,24 +1059,13 @@
 
   case JVM_CONSTANT_InvokeDynamic:
   {
-    int k1 = invoke_dynamic_bootstrap_method_ref_index_at(index1);
-    int k2 = cp2->invoke_dynamic_bootstrap_method_ref_index_at(index2);
-    bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
-    if (!match)  return false;
-    k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
-    k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
-    match = compare_entry_to(k1, cp2, k2, CHECK_false);
-    if (!match)  return false;
-    int argc = invoke_dynamic_argument_count_at(index1);
-    if (argc == cp2->invoke_dynamic_argument_count_at(index2)) {
-      for (int j = 0; j < argc; j++) {
-        k1 = invoke_dynamic_argument_index_at(index1, j);
-        k2 = cp2->invoke_dynamic_argument_index_at(index2, j);
-        match = compare_entry_to(k1, cp2, k2, CHECK_false);
-        if (!match)  return false;
-      }
-      return true;           // got through loop; all elements equal
-    }
+    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);
+    bool match = compare_entry_to(k1, cp2, k2, CHECK_false) &&
+                 compare_operand_to(i1, cp2, i2, CHECK_false);
+    return match;
   } break;
 
   case JVM_CONSTANT_String:
@@ -1095,6 +1100,80 @@
 } // 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(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(constantPoolHandle from_cp,
                                  constantPoolHandle to_cp,
                                  TRAPS) {
@@ -1357,6 +1436,46 @@
 } // 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, 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,
+                    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) {
--- a/src/share/vm/oops/constantPool.hpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/oops/constantPool.hpp	Fri Apr 26 08:40:24 2013 -0700
@@ -111,7 +111,6 @@
     int                _version;
   } _saved;
 
-  Monitor*             _lock;
 
   void set_tags(Array<u1>* tags)               { _tags = tags; }
   void tag_at_put(int which, jbyte t)          { tags()->at_put(which, t); }
@@ -567,6 +566,47 @@
          _indy_argc_offset = 1,  // u2 argc
          _indy_argv_offset = 2   // u2 argv[argc]
   };
+
+  // These functions are used in RedefineClasses for CP merge
+
+  int operand_offset_at(int bootstrap_specifier_index) {
+    assert(0 <= bootstrap_specifier_index &&
+           bootstrap_specifier_index < operand_array_length(operands()),
+           "Corrupted CP operands");
+    return operand_offset_at(operands(), bootstrap_specifier_index);
+  }
+  int operand_bootstrap_method_ref_index_at(int bootstrap_specifier_index) {
+    int offset = operand_offset_at(bootstrap_specifier_index);
+    return operands()->at(offset + _indy_bsm_offset);
+  }
+  int operand_argument_count_at(int bootstrap_specifier_index) {
+    int offset = operand_offset_at(bootstrap_specifier_index);
+    int argc = operands()->at(offset + _indy_argc_offset);
+    return argc;
+  }
+  int operand_argument_index_at(int bootstrap_specifier_index, int j) {
+    int offset = operand_offset_at(bootstrap_specifier_index);
+    return operands()->at(offset + _indy_argv_offset + j);
+  }
+  int operand_next_offset_at(int bootstrap_specifier_index) {
+    int offset = operand_offset_at(bootstrap_specifier_index) + _indy_argv_offset
+                   + operand_argument_count_at(bootstrap_specifier_index);
+    return offset;
+  }
+  // Compare a bootsrap specifier in the operands arrays
+  bool compare_operand_to(int bootstrap_specifier_index1, constantPoolHandle cp2,
+                          int bootstrap_specifier_index2, TRAPS);
+  // Find a bootsrap specifier in the operands array
+  int find_matching_operand(int bootstrap_specifier_index, constantPoolHandle search_cp,
+                            int operands_cur_len, TRAPS);
+  // Resize the operands array with delta_len and delta_size
+  void resize_operands(int delta_len, int delta_size, TRAPS);
+  // Extend the operands array with the length and size of the ext_cp operands
+  void extend_operands(constantPoolHandle ext_cp, TRAPS);
+  // Shrink the operands array to a smaller array with new_len length
+  void shrink_operands(int new_len, TRAPS);
+
+
   int invoke_dynamic_bootstrap_method_ref_index_at(int which) {
     assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
     int op_base = invoke_dynamic_operand_base(which);
@@ -782,8 +822,17 @@
 
   void set_resolved_reference_length(int length) { _saved._resolved_reference_length = length; }
   int  resolved_reference_length() const  { return _saved._resolved_reference_length; }
-  void set_lock(Monitor* lock)            { _lock = lock; }
-  Monitor* lock()                         { return _lock; }
+
+  // lock() may return null -- constant pool updates may happen before this lock is
+  // initialized, because the _pool_holder has not been fully initialized and
+  // has not been registered into the system dictionary. In this case, no other
+  // thread can be modifying this constantpool, so no synchronization is
+  // necessary.
+  //
+  // Use cplock() like this:
+  //    oop cplock = cp->lock();
+  //    ObjectLocker ol(cplock , THREAD, cplock != NULL);
+  oop lock();
 
   // Decrease ref counts of symbols that are in the constant pool
   // when the holder class is unloaded
--- a/src/share/vm/oops/cpCache.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/oops/cpCache.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -266,7 +266,8 @@
   // the lock, so that when the losing writer returns, he can use the linked
   // cache entry.
 
-  MonitorLockerEx ml(cpool->lock());
+  oop cplock = cpool->lock();
+  ObjectLocker ol(cplock, Thread::current(), cplock != NULL);
   if (!is_f1_null()) {
     return;
   }
--- a/src/share/vm/oops/instanceKlass.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/oops/instanceKlass.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -54,6 +54,7 @@
 #include "runtime/javaCalls.hpp"
 #include "runtime/mutexLocker.hpp"
 #include "runtime/thread.inline.hpp"
+#include "services/classLoadingService.hpp"
 #include "services/threadService.hpp"
 #include "utilities/dtrace.hpp"
 #include "utilities/macros.hpp"
@@ -418,25 +419,6 @@
   set_annotations(NULL);
 }
 
-volatile oop InstanceKlass::init_lock() const {
-  volatile oop lock = _init_lock;  // read once
-  assert((oop)lock != NULL || !is_not_initialized(), // initialized or in_error state
-         "only fully initialized state can have a null lock");
-  return lock;
-}
-
-// Set the initialization lock to null so the object can be GC'ed.  Any racing
-// threads to get this lock will see a null lock and will not lock.
-// That's okay because they all check for initialized state after getting
-// the lock and return.
-void InstanceKlass::fence_and_clear_init_lock() {
-  // make sure previous stores are all done, notably the init_state.
-  OrderAccess::storestore();
-  klass_oop_store(&_init_lock, NULL);
-  assert(!is_not_initialized(), "class must be initialized now");
-}
-
-
 bool InstanceKlass::should_be_initialized() const {
   return !is_initialized();
 }
@@ -473,7 +455,7 @@
 void InstanceKlass::eager_initialize_impl(instanceKlassHandle this_oop) {
   EXCEPTION_MARK;
   volatile oop init_lock = this_oop->init_lock();
-  ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
+  ObjectLocker ol(init_lock, THREAD);
 
   // abort if someone beat us to the initialization
   if (!this_oop->is_not_initialized()) return;  // note: not equivalent to is_initialized()
@@ -492,7 +474,6 @@
   } else {
     // linking successfull, mark class as initialized
     this_oop->set_init_state (fully_initialized);
-    this_oop->fence_and_clear_init_lock();
     // trace
     if (TraceClassInitialization) {
       ResourceMark rm(THREAD);
@@ -619,7 +600,7 @@
   // verification & rewriting
   {
     volatile oop init_lock = this_oop->init_lock();
-    ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
+    ObjectLocker ol(init_lock, THREAD);
     // rewritten will have been set if loader constraint error found
     // on an earlier link attempt
     // don't verify or rewrite if already rewritten
@@ -742,7 +723,7 @@
   // Step 1
   {
     volatile oop init_lock = this_oop->init_lock();
-    ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
+    ObjectLocker ol(init_lock, THREAD);
 
     Thread *self = THREAD; // it's passed the current thread
 
@@ -890,9 +871,8 @@
 
 void InstanceKlass::set_initialization_state_and_notify_impl(instanceKlassHandle this_oop, ClassState state, TRAPS) {
   volatile oop init_lock = this_oop->init_lock();
-  ObjectLocker ol(init_lock, THREAD, init_lock != NULL);
+  ObjectLocker ol(init_lock, THREAD);
   this_oop->set_init_state(state);
-  this_oop->fence_and_clear_init_lock();
   ol.notify_all(CHECK);
 }
 
@@ -2312,7 +2292,29 @@
   m->clear_all_breakpoints();
 }
 
+
+void InstanceKlass::notify_unload_class(InstanceKlass* ik) {
+  // notify the debugger
+  if (JvmtiExport::should_post_class_unload()) {
+    JvmtiExport::post_class_unload(ik);
+  }
+
+  // notify ClassLoadingService of class unload
+  ClassLoadingService::notify_class_unloaded(ik);
+}
+
+void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
+  // Clean up C heap
+  ik->release_C_heap_structures();
+  ik->constants()->release_C_heap_structures();
+}
+
 void InstanceKlass::release_C_heap_structures() {
+
+  // Can't release the constant pool here because the constant pool can be
+  // deallocated separately from the InstanceKlass for default methods and
+  // redefine classes.
+
   // Deallocate oop map cache
   if (_oop_map_cache != NULL) {
     delete _oop_map_cache;
@@ -2837,7 +2839,7 @@
   st->print(BULLET"protection domain: "); ((InstanceKlass*)this)->protection_domain()->print_value_on(st); st->cr();
   st->print(BULLET"host class:        "); host_klass()->print_value_on_maybe_null(st); st->cr();
   st->print(BULLET"signers:           "); signers()->print_value_on(st);               st->cr();
-  st->print(BULLET"init_lock:         "); ((oop)_init_lock)->print_value_on(st);             st->cr();
+  st->print(BULLET"init_lock:         "); ((oop)_init_lock)->print_value_on(st);       st->cr();
   if (source_file_name() != NULL) {
     st->print(BULLET"source file:       ");
     source_file_name()->print_value_on(st);
--- a/src/share/vm/oops/instanceKlass.hpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/oops/instanceKlass.hpp	Fri Apr 26 08:40:24 2013 -0700
@@ -184,8 +184,9 @@
   oop             _protection_domain;
   // Class signers.
   objArrayOop     _signers;
-  // Initialization lock.  Must be one per class and it has to be a VM internal
-  // object so java code cannot lock it (like the mirror)
+  // Lock for (1) initialization; (2) access to the ConstantPool of this class.
+  // Must be one per class and it has to be a VM internal object so java code
+  // cannot lock it (like the mirror).
   // It has to be an object not a Mutex because it's held through java calls.
   volatile oop    _init_lock;
 
@@ -236,7 +237,7 @@
     _misc_rewritten            = 1 << 0, // methods rewritten.
     _misc_has_nonstatic_fields = 1 << 1, // for sizing with UseCompressedOops
     _misc_should_verify_class  = 1 << 2, // allow caching of preverification
-    _misc_is_anonymous         = 1 << 3, // has embedded _inner_classes field
+    _misc_is_anonymous         = 1 << 3, // has embedded _host_klass field
     _misc_is_contended         = 1 << 4, // marked with contended annotation
     _misc_has_default_methods  = 1 << 5  // class/superclass/implemented interfaces has default methods
   };
@@ -934,7 +935,9 @@
   // referenced by handles.
   bool on_stack() const { return _constants->on_stack(); }
 
-  void release_C_heap_structures();
+  // callbacks for actions during class unloading
+  static void notify_unload_class(InstanceKlass* ik);
+  static void release_C_heap_structures(InstanceKlass* ik);
 
   // Parallel Scavenge and Parallel Old
   PARALLEL_GC_DECLS
@@ -968,6 +971,7 @@
 #endif // INCLUDE_ALL_GCS
 
   u2 idnum_allocated_count() const      { return _idnum_allocated_count; }
+
 private:
   // initialization state
 #ifdef ASSERT
@@ -994,9 +998,10 @@
          { OrderAccess::release_store_ptr(&_methods_cached_itable_indices, indices); }
 
   // Lock during initialization
-  volatile oop init_lock() const;
-  void set_init_lock(oop value)      { klass_oop_store(&_init_lock, value); }
-  void fence_and_clear_init_lock();  // after fully_initialized
+public:
+  volatile oop init_lock() const     {return _init_lock; }
+private:
+  void set_init_lock(oop value) { klass_oop_store(&_init_lock, value); }
 
   // Offsets for memory management
   oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;}
@@ -1022,6 +1027,8 @@
   // Returns the array class with this class as element type
   Klass* array_klass_impl(bool or_null, TRAPS);
 
+  // Free CHeap allocated fields.
+  void release_C_heap_structures();
 public:
   // CDS support - remove and restore oops from metadata. Oops are not shared.
   virtual void remove_unshareable_info();
--- a/src/share/vm/prims/jvmtiEnv.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/prims/jvmtiEnv.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -259,7 +259,8 @@
       // bytes to the InstanceKlass here because they have not been
       // validated and we're not at a safepoint.
       constantPoolHandle  constants(current_thread, ikh->constants());
-      MonitorLockerEx ml(constants->lock());    // lock constant pool while we query it
+      oop cplock = constants->lock();
+      ObjectLocker ol(cplock, current_thread, cplock != NULL);    // lock constant pool while we query it
 
       JvmtiClassFileReconstituter reconstituter(ikh);
       if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
@@ -2417,7 +2418,8 @@
 
   instanceKlassHandle ikh(thread, k_oop);
   constantPoolHandle  constants(thread, ikh->constants());
-  MonitorLockerEx ml(constants->lock());    // lock constant pool while we query it
+  oop cplock = constants->lock();
+  ObjectLocker ol(cplock, thread, cplock != NULL);    // lock constant pool while we query it
 
   JvmtiConstantPoolReconstituter reconstituter(ikh);
   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
--- a/src/share/vm/prims/jvmtiRedefineClasses.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/prims/jvmtiRedefineClasses.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -415,20 +415,26 @@
     // this is an indirect CP entry so it needs special handling
     case JVM_CONSTANT_InvokeDynamic:
     {
-      // TBD: cross-checks and possible extra appends into CP and bsm operands
-      // are needed as well. This issue is tracked by a separate bug 8007037.
-      int bss_idx = scratch_cp->invoke_dynamic_bootstrap_specifier_index(scratch_i);
-
-      int ref_i = scratch_cp->invoke_dynamic_name_and_type_ref_index_at(scratch_i);
-      int new_ref_i = find_or_append_indirect_entry(scratch_cp, ref_i, merge_cp_p,
+      // Index of the bootstrap specifier in the operands array
+      int old_bs_i = scratch_cp->invoke_dynamic_bootstrap_specifier_index(scratch_i);
+      int new_bs_i = find_or_append_operand(scratch_cp, old_bs_i, merge_cp_p,
+                                            merge_cp_length_p, THREAD);
+      // The bootstrap method NameAndType_info index
+      int old_ref_i = scratch_cp->invoke_dynamic_name_and_type_ref_index_at(scratch_i);
+      int new_ref_i = find_or_append_indirect_entry(scratch_cp, old_ref_i, merge_cp_p,
                                                     merge_cp_length_p, THREAD);
-      if (new_ref_i != ref_i) {
+      if (new_bs_i != old_bs_i) {
         RC_TRACE(0x00080000,
-                 ("InvokeDynamic entry@%d name_and_type ref_index change: %d to %d",
-                  *merge_cp_length_p, ref_i, new_ref_i));
+                 ("InvokeDynamic entry@%d bootstrap_method_attr_index change: %d to %d",
+                  *merge_cp_length_p, old_bs_i, new_bs_i));
       }
-
-      (*merge_cp_p)->invoke_dynamic_at_put(*merge_cp_length_p, bss_idx, new_ref_i);
+      if (new_ref_i != old_ref_i) {
+        RC_TRACE(0x00080000,
+                 ("InvokeDynamic entry@%d name_and_type_index change: %d to %d",
+                  *merge_cp_length_p, old_ref_i, new_ref_i));
+      }
+
+      (*merge_cp_p)->invoke_dynamic_at_put(*merge_cp_length_p, new_bs_i, new_ref_i);
       if (scratch_i != *merge_cp_length_p) {
         // The new entry in *merge_cp_p is at a different index than
         // the new entry in scratch_cp so we need to map the index values.
@@ -492,6 +498,105 @@
 } // end find_or_append_indirect_entry()
 
 
+// Append a bootstrap specifier into the merge_cp operands that is semantically equal
+// to the scratch_cp operands bootstrap specifier passed by the old_bs_i index.
+// Recursively append new merge_cp entries referenced by the new bootstrap specifier.
+void VM_RedefineClasses::append_operand(constantPoolHandle scratch_cp, int old_bs_i,
+       constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS) {
+
+  int old_ref_i = scratch_cp->operand_bootstrap_method_ref_index_at(old_bs_i);
+  int new_ref_i = find_or_append_indirect_entry(scratch_cp, old_ref_i, merge_cp_p,
+                                                merge_cp_length_p, THREAD);
+  if (new_ref_i != old_ref_i) {
+    RC_TRACE(0x00080000,
+             ("operands entry@%d bootstrap method ref_index change: %d to %d",
+              _operands_cur_length, old_ref_i, new_ref_i));
+  }
+
+  Array<u2>* merge_ops = (*merge_cp_p)->operands();
+  int new_bs_i = _operands_cur_length;
+  // We have _operands_cur_length == 0 when the merge_cp operands is empty yet.
+  // However, the operand_offset_at(0) was set in the extend_operands() call.
+  int new_base = (new_bs_i == 0) ? (*merge_cp_p)->operand_offset_at(0)
+                                 : (*merge_cp_p)->operand_next_offset_at(new_bs_i - 1);
+  int argc     = scratch_cp->operand_argument_count_at(old_bs_i);
+
+  ConstantPool::operand_offset_at_put(merge_ops, _operands_cur_length, new_base);
+  merge_ops->at_put(new_base++, new_ref_i);
+  merge_ops->at_put(new_base++, argc);
+
+  for (int i = 0; i < argc; i++) {
+    int old_arg_ref_i = scratch_cp->operand_argument_index_at(old_bs_i, i);
+    int new_arg_ref_i = find_or_append_indirect_entry(scratch_cp, old_arg_ref_i, merge_cp_p,
+                                                      merge_cp_length_p, THREAD);
+    merge_ops->at_put(new_base++, new_arg_ref_i);
+    if (new_arg_ref_i != old_arg_ref_i) {
+      RC_TRACE(0x00080000,
+               ("operands entry@%d bootstrap method argument ref_index change: %d to %d",
+                _operands_cur_length, old_arg_ref_i, new_arg_ref_i));
+    }
+  }
+  if (old_bs_i != _operands_cur_length) {
+    // The bootstrap specifier in *merge_cp_p is at a different index than
+    // that in scratch_cp so we need to map the index values.
+    map_operand_index(old_bs_i, new_bs_i);
+  }
+  _operands_cur_length++;
+} // end append_operand()
+
+
+int VM_RedefineClasses::find_or_append_operand(constantPoolHandle scratch_cp,
+      int old_bs_i, constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS) {
+
+  int new_bs_i = old_bs_i; // bootstrap specifier index
+  bool match = (old_bs_i < _operands_cur_length) &&
+               scratch_cp->compare_operand_to(old_bs_i, *merge_cp_p, old_bs_i, THREAD);
+
+  if (!match) {
+    // forward reference in *merge_cp_p or not a direct match
+    int found_i = scratch_cp->find_matching_operand(old_bs_i, *merge_cp_p,
+                                                    _operands_cur_length, THREAD);
+    if (found_i != -1) {
+      guarantee(found_i != old_bs_i, "compare_operand_to() and find_matching_operand() disagree");
+      // found a matching operand somewhere else in *merge_cp_p so just need a mapping
+      new_bs_i = found_i;
+      map_operand_index(old_bs_i, found_i);
+    } else {
+      // no match found so we have to append this bootstrap specifier to *merge_cp_p
+      append_operand(scratch_cp, old_bs_i, merge_cp_p, merge_cp_length_p, THREAD);
+      new_bs_i = _operands_cur_length - 1;
+    }
+  }
+  return new_bs_i;
+} // end find_or_append_operand()
+
+
+void VM_RedefineClasses::finalize_operands_merge(constantPoolHandle merge_cp, TRAPS) {
+  if (merge_cp->operands() == NULL) {
+    return;
+  }
+  // Shrink the merge_cp operands
+  merge_cp->shrink_operands(_operands_cur_length, CHECK);
+
+  if (RC_TRACE_ENABLED(0x00040000)) {
+    // don't want to loop unless we are tracing
+    int count = 0;
+    for (int i = 1; i < _operands_index_map_p->length(); i++) {
+      int value = _operands_index_map_p->at(i);
+      if (value != -1) {
+        RC_TRACE_WITH_THREAD(0x00040000, THREAD,
+          ("operands_index_map[%d]: old=%d new=%d", count, i, value));
+        count++;
+      }
+    }
+  }
+  // Clean-up
+  _operands_index_map_p = NULL;
+  _operands_cur_length = 0;
+  _operands_index_map_count = 0;
+} // end finalize_operands_merge()
+
+
 jvmtiError VM_RedefineClasses::compare_and_normalize_class_versions(
              instanceKlassHandle the_class,
              instanceKlassHandle scratch_class) {
@@ -765,6 +870,31 @@
 } // end find_new_index()
 
 
+// Find new bootstrap specifier index value for old bootstrap specifier index
+// value by seaching the index map. Returns unused index (-1) if there is
+// no mapped value for the old bootstrap specifier index.
+int VM_RedefineClasses::find_new_operand_index(int old_index) {
+  if (_operands_index_map_count == 0) {
+    // map is empty so nothing can be found
+    return -1;
+  }
+
+  if (old_index == -1 || old_index >= _operands_index_map_p->length()) {
+    // The old_index is out of range so it is not mapped.
+    // This should not happen in regular constant pool merging use.
+    return -1;
+  }
+
+  int value = _operands_index_map_p->at(old_index);
+  if (value == -1) {
+    // the old_index is not mapped
+    return -1;
+  }
+
+  return value;
+} // end find_new_operand_index()
+
+
 // Returns true if the current mismatch is due to a resolved/unresolved
 // class pair. Otherwise, returns false.
 bool VM_RedefineClasses::is_unresolved_class_mismatch(constantPoolHandle cp1,
@@ -1014,6 +1144,25 @@
 } // end map_index()
 
 
+// Map old_index to new_index as needed.
+void VM_RedefineClasses::map_operand_index(int old_index, int new_index) {
+  if (find_new_operand_index(old_index) != -1) {
+    // old_index is already mapped
+    return;
+  }
+
+  if (old_index == new_index) {
+    // no mapping is needed
+    return;
+  }
+
+  _operands_index_map_p->at_put(old_index, new_index);
+  _operands_index_map_count++;
+
+  RC_TRACE(0x00040000, ("mapped bootstrap specifier at index %d to %d", old_index, new_index));
+} // end map_index()
+
+
 // Merge old_cp and scratch_cp and return the results of the merge via
 // merge_cp_p. The number of entries in *merge_cp_p is returned via
 // merge_cp_length_p. The entries in old_cp occupy the same locations
@@ -1086,6 +1235,7 @@
     } // end for each old_cp entry
 
     ConstantPool::copy_operands(old_cp, *merge_cp_p, CHECK_0);
+    (*merge_cp_p)->extend_operands(scratch_cp, CHECK_0);
 
     // We don't need to sanity check that *merge_cp_length_p is within
     // *merge_cp_p bounds since we have the minimum on-entry check above.
@@ -1198,6 +1348,8 @@
         CHECK_0);
     }
 
+    finalize_operands_merge(*merge_cp_p, THREAD);
+
     RC_TRACE_WITH_THREAD(0x00020000, THREAD,
       ("after pass 1b: merge_cp_len=%d, scratch_i=%d, index_map_len=%d",
       *merge_cp_length_p, scratch_i, _index_map_count));
@@ -1270,6 +1422,11 @@
   _index_map_count = 0;
   _index_map_p = new intArray(scratch_cp->length(), -1);
 
+  _operands_cur_length = ConstantPool::operand_array_length(old_cp->operands());
+  _operands_index_map_count = 0;
+  _operands_index_map_p = new intArray(
+    ConstantPool::operand_array_length(scratch_cp->operands()), -1);
+
   // reference to the cp holder is needed for copy_operands()
   merge_cp->set_pool_holder(scratch_class());
   bool result = merge_constant_pools(old_cp, scratch_cp, &merge_cp,
@@ -1400,7 +1557,6 @@
   return true;
 } // end rewrite_cp_refs()
 
-
 // Rewrite constant pool references in the methods.
 bool VM_RedefineClasses::rewrite_cp_refs_in_methods(
        instanceKlassHandle scratch_class, TRAPS) {
--- a/src/share/vm/prims/jvmtiRedefineClasses.hpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/prims/jvmtiRedefineClasses.hpp	Fri Apr 26 08:40:24 2013 -0700
@@ -359,8 +359,15 @@
   // _index_map_p contains any entries.
   int                         _index_map_count;
   intArray *                  _index_map_p;
+
+  // _operands_index_map_count is just an optimization for knowing if
+  // _operands_index_map_p contains any entries.
+  int                         _operands_cur_length;
+  int                         _operands_index_map_count;
+  intArray *                  _operands_index_map_p;
+
   // ptr to _class_count scratch_classes
-  Klass**                   _scratch_classes;
+  Klass**                     _scratch_classes;
   jvmtiError                  _res;
 
   // Performance measurement support. These timers do not cover all
@@ -422,12 +429,19 @@
   // Support for constant pool merging (these routines are in alpha order):
   void append_entry(constantPoolHandle scratch_cp, int scratch_i,
     constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS);
+  void append_operand(constantPoolHandle scratch_cp, int scratch_bootstrap_spec_index,
+    constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS);
+  void finalize_operands_merge(constantPoolHandle merge_cp, TRAPS);
   int find_or_append_indirect_entry(constantPoolHandle scratch_cp, int scratch_i,
     constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS);
+  int find_or_append_operand(constantPoolHandle scratch_cp, int scratch_bootstrap_spec_index,
+    constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS);
   int find_new_index(int old_index);
+  int find_new_operand_index(int old_bootstrap_spec_index);
   bool is_unresolved_class_mismatch(constantPoolHandle cp1, int index1,
     constantPoolHandle cp2, int index2);
   void map_index(constantPoolHandle scratch_cp, int old_index, int new_index);
+  void map_operand_index(int old_bootstrap_spec_index, int new_bootstrap_spec_index);
   bool merge_constant_pools(constantPoolHandle old_cp,
     constantPoolHandle scratch_cp, constantPoolHandle *merge_cp_p,
     int *merge_cp_length_p, TRAPS);
--- a/src/share/vm/services/memBaseline.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/services/memBaseline.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2013, 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
@@ -23,9 +23,12 @@
  */
 #include "precompiled.hpp"
 #include "memory/allocation.hpp"
+#include "runtime/safepoint.hpp"
+#include "runtime/thread.inline.hpp"
 #include "services/memBaseline.hpp"
 #include "services/memTracker.hpp"
 
+
 MemType2Name MemBaseline::MemType2NameMap[NUMBER_OF_MEMORY_TYPE] = {
   {mtJavaHeap,   "Java Heap"},
   {mtClass,      "Class"},
@@ -149,6 +152,14 @@
   return true;
 }
 
+// check if there is a safepoint in progress, if so, block the thread
+// for the safepoint
+void MemBaseline::check_safepoint(JavaThread* thr) {
+  if (SafepointSynchronize::is_synchronizing()) {
+    SafepointSynchronize::block(thr);
+  }
+}
+
 // baseline mmap'd memory records, generate overall summary and summaries by
 // memory types
 bool MemBaseline::baseline_vm_summary(const MemPointerArray* vm_records) {
@@ -306,7 +317,7 @@
         committed_rec->pc() != vm_ptr->pc()) {
         if (!_vm_map->append(vm_ptr)) {
           return false;
-  }
+        }
         committed_rec = (VMMemRegionEx*)_vm_map->at(_vm_map->length() - 1);
     } else {
         committed_rec->expand_region(vm_ptr->addr(), vm_ptr->size());
@@ -344,16 +355,27 @@
 
 // baseline a snapshot. If summary_only = false, memory usages aggregated by
 // callsites are also baselined.
+// The method call can be lengthy, especially when detail tracking info is
+// requested. So the method checks for safepoint explicitly.
 bool MemBaseline::baseline(MemSnapshot& snapshot, bool summary_only) {
-  MutexLockerEx snapshot_locker(snapshot._lock, true);
+  Thread* THREAD = Thread::current();
+  assert(THREAD->is_Java_thread(), "must be a JavaThread");
+  MutexLocker snapshot_locker(snapshot._lock);
   reset();
-  _baselined = baseline_malloc_summary(snapshot._alloc_ptrs) &&
-               baseline_vm_summary(snapshot._vm_ptrs);
+  _baselined = baseline_malloc_summary(snapshot._alloc_ptrs);
+  if (_baselined) {
+    check_safepoint((JavaThread*)THREAD);
+    _baselined = baseline_vm_summary(snapshot._vm_ptrs);
+  }
   _number_of_classes = snapshot.number_of_classes();
 
   if (!summary_only && MemTracker::track_callsite() && _baselined) {
-    _baselined =  baseline_malloc_details(snapshot._alloc_ptrs) &&
-      baseline_vm_details(snapshot._vm_ptrs);
+    check_safepoint((JavaThread*)THREAD);
+    _baselined =  baseline_malloc_details(snapshot._alloc_ptrs);
+    if (_baselined) {
+      check_safepoint((JavaThread*)THREAD);
+      _baselined =  baseline_vm_details(snapshot._vm_ptrs);
+    }
   }
   return _baselined;
 }
--- a/src/share/vm/services/memBaseline.hpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/services/memBaseline.hpp	Fri Apr 26 08:40:24 2013 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2013, 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
@@ -330,6 +330,9 @@
   // should not use copy constructor
   MemBaseline(MemBaseline& copy) { ShouldNotReachHere(); }
 
+  // check and block at a safepoint
+  static inline void check_safepoint(JavaThread* thr);
+
  public:
   // create a memory baseline
   MemBaseline();
--- a/src/share/vm/services/memTracker.cpp	Fri Apr 26 00:40:22 2013 -0700
+++ b/src/share/vm/services/memTracker.cpp	Fri Apr 26 08:40:24 2013 -0700
@@ -573,7 +573,7 @@
 
 // baseline current memory snapshot
 bool MemTracker::baseline() {
-  MutexLockerEx lock(_query_lock, true);
+  MutexLocker lock(_query_lock);
   MemSnapshot* snapshot = get_snapshot();
   if (snapshot != NULL) {
     return _baseline.baseline(*snapshot, false);
@@ -584,7 +584,7 @@
 // print memory usage from current snapshot
 bool MemTracker::print_memory_usage(BaselineOutputer& out, size_t unit, bool summary_only) {
   MemBaseline  baseline;
-  MutexLockerEx lock(_query_lock, true);
+  MutexLocker  lock(_query_lock);
   MemSnapshot* snapshot = get_snapshot();
   if (snapshot != NULL && baseline.baseline(*snapshot, summary_only)) {
     BaselineReporter reporter(out, unit);
@@ -597,7 +597,7 @@
 // Whitebox API for blocking until the current generation of NMT data has been merged
 bool MemTracker::wbtest_wait_for_data_merge() {
   // NMT can't be shutdown while we're holding _query_lock
-  MutexLockerEx lock(_query_lock, true);
+  MutexLocker lock(_query_lock);
   assert(_worker_thread != NULL, "Invalid query");
   // the generation at query time, so NMT will spin till this generation is processed
   unsigned long generation_at_query_time = SequenceGenerator::current_generation();
@@ -641,7 +641,7 @@
 
 // compare memory usage between current snapshot and baseline
 bool MemTracker::compare_memory_usage(BaselineOutputer& out, size_t unit, bool summary_only) {
-  MutexLockerEx lock(_query_lock, true);
+  MutexLocker lock(_query_lock);
   if (_baseline.baselined()) {
     MemBaseline baseline;
     MemSnapshot* snapshot = get_snapshot();