view src/share/vm/classfile/javaClasses.hpp @ 1091:6aa7255741f3

6906727: UseCompressedOops: some card-marking fixes related to object arrays Summary: Introduced a new write_ref_array(HeapWords* start, size_t count) method that does the requisite MemRegion range calculation so (some of the) clients of the erstwhile write_ref_array(MemRegion mr) do not need to worry. This removed all external uses of array_size(), which was also simplified and made private. Asserts were added to catch other possible issues. Further, less essential, fixes stemming from this investigation are deferred to CR 6904516 (to follow shortly in hs17). Reviewed-by: kvn, coleenp, jmasa
author ysr
date Thu, 03 Dec 2009 15:01:57 -0800
parents 987e948ebbc8
children 389049f3f393
line wrap: on
line source

/*
 * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

// Interface for manipulating the basic Java classes.
//
// All dependencies on layout of actual Java classes should be kept here.
// If the layout of any of the classes above changes the offsets must be adjusted.
//
// For most classes we hardwire the offsets for performance reasons. In certain
// cases (e.g. java.security.AccessControlContext) we compute the offsets at
// startup since the layout here differs between JDK1.2 and JDK1.3.
//
// Note that fields (static and non-static) are arranged with oops before non-oops
// on a per class basis. The offsets below have to reflect this ordering.
//
// When editing the layouts please update the check_offset verification code
// correspondingly. The names in the enums must be identical to the actual field
// names in order for the verification code to work.


// Interface to java.lang.String objects

class java_lang_String : AllStatic {
 private:
  enum {
    hc_value_offset  = 0,
    hc_offset_offset = 1
    //hc_count_offset = 2  -- not a word-scaled offset
    //hc_hash_offset  = 3  -- not a word-scaled offset
  };

  static int value_offset;
  static int offset_offset;
  static int count_offset;
  static int hash_offset;

  static Handle basic_create(int length, bool tenured, TRAPS);
  static Handle basic_create_from_unicode(jchar* unicode, int length, bool tenured, TRAPS);

  static void set_value( oop string, typeArrayOop buffer) { string->obj_field_put(value_offset,  (oop)buffer); }
  static void set_offset(oop string, int offset)          { string->int_field_put(offset_offset, offset); }
  static void set_count( oop string, int count)           { string->int_field_put(count_offset,  count);  }

 public:
  // Instance creation
  static Handle create_from_unicode(jchar* unicode, int len, TRAPS);
  static Handle create_tenured_from_unicode(jchar* unicode, int len, TRAPS);
  static oop    create_oop_from_unicode(jchar* unicode, int len, TRAPS);
  static Handle create_from_str(const char* utf8_str, TRAPS);
  static oop    create_oop_from_str(const char* utf8_str, TRAPS);
  static Handle create_from_symbol(symbolHandle symbol, TRAPS);
  static Handle create_from_platform_dependent_str(const char* str, TRAPS);
  static Handle char_converter(Handle java_string, jchar from_char, jchar to_char, TRAPS);

  static int value_offset_in_bytes()  { return value_offset;  }
  static int count_offset_in_bytes()  { return count_offset;  }
  static int offset_offset_in_bytes() { return offset_offset; }
  static int hash_offset_in_bytes()   { return hash_offset;   }

  // Accessors
  static typeArrayOop value(oop java_string) {
    assert(is_instance(java_string), "must be java_string");
    return (typeArrayOop) java_string->obj_field(value_offset);
  }
  static int offset(oop java_string) {
    assert(is_instance(java_string), "must be java_string");
    return java_string->int_field(offset_offset);
  }
  static int length(oop java_string) {
    assert(is_instance(java_string), "must be java_string");
    return java_string->int_field(count_offset);
  }
  static int utf8_length(oop java_string);

  // String converters
  static char*  as_utf8_string(oop java_string);
  static char*  as_utf8_string(oop java_string, int start, int len);
  static char*  as_platform_dependent_str(Handle java_string, TRAPS);
  static jchar* as_unicode_string(oop java_string, int& length);

  static bool equals(oop java_string, jchar* chars, int len);

  // Conversion between '.' and '/' formats
  static Handle externalize_classname(Handle java_string, TRAPS) { return char_converter(java_string, '/', '.', THREAD); }
  static Handle internalize_classname(Handle java_string, TRAPS) { return char_converter(java_string, '.', '/', THREAD); }

  // Conversion
  static symbolHandle as_symbol(Handle java_string, TRAPS);
  static symbolOop as_symbol_or_null(oop java_string);

  // Testers
  static bool is_instance(oop obj) {
    return obj != NULL && obj->klass() == SystemDictionary::string_klass();
  }

  // Debugging
  static void print(Handle java_string, outputStream* st);
  friend class JavaClasses;
};


// Interface to java.lang.Class objects

class java_lang_Class : AllStatic {
   friend class VMStructs;
 private:
  // The fake offsets are added by the class loader when java.lang.Class is loaded

  enum {
    hc_klass_offset                = 0,
    hc_array_klass_offset          = 1,
    hc_resolved_constructor_offset = 2,
    hc_number_of_fake_oop_fields   = 3
  };

  static int klass_offset;
  static int resolved_constructor_offset;
  static int array_klass_offset;
  static int number_of_fake_oop_fields;

  static void compute_offsets();
  static bool offsets_computed;
  static int classRedefinedCount_offset;
  static int parallelCapable_offset;

 public:
  // Instance creation
  static oop  create_mirror(KlassHandle k, TRAPS);
  static oop  create_basic_type_mirror(const char* basic_type_name, BasicType type, TRAPS);
  // Conversion
  static klassOop as_klassOop(oop java_class);
  static BasicType as_BasicType(oop java_class, klassOop* reference_klass = NULL);
  static BasicType as_BasicType(oop java_class, KlassHandle* reference_klass) {
    klassOop refk_oop = NULL;
    BasicType result = as_BasicType(java_class, &refk_oop);
    (*reference_klass) = KlassHandle(refk_oop);
    return result;
  }
  static symbolOop as_signature(oop java_class, bool intern_if_not_found, TRAPS);
  static void print_signature(oop java_class, outputStream *st);
  // Testing
  static bool is_instance(oop obj) {
    return obj != NULL && obj->klass() == SystemDictionary::class_klass();
  }
  static bool is_primitive(oop java_class);
  static BasicType primitive_type(oop java_class);
  static oop primitive_mirror(BasicType t);
  // JVM_NewInstance support
  static methodOop resolved_constructor(oop java_class);
  static void set_resolved_constructor(oop java_class, methodOop constructor);
  // JVM_NewArray support
  static klassOop array_klass(oop java_class);
  static void set_array_klass(oop java_class, klassOop klass);
  // compiler support for class operations
  static int klass_offset_in_bytes() { return klass_offset; }
  static int resolved_constructor_offset_in_bytes() { return resolved_constructor_offset; }
  static int array_klass_offset_in_bytes() { return array_klass_offset; }
  // Support for classRedefinedCount field
  static int classRedefinedCount(oop the_class_mirror);
  static void set_classRedefinedCount(oop the_class_mirror, int value);
  // Support for parallelCapable field
  static bool parallelCapable(oop the_class_mirror);
  // Debugging
  friend class JavaClasses;
  friend class instanceKlass;   // verification code accesses offsets
  friend class ClassFileParser; // access to number_of_fake_fields
};

// Interface to java.lang.Thread objects

class java_lang_Thread : AllStatic {
 private:
  // Note that for this class the layout changed between JDK1.2 and JDK1.3,
  // so we compute the offsets at startup rather than hard-wiring them.
  static int _name_offset;
  static int _group_offset;
  static int _contextClassLoader_offset;
  static int _inheritedAccessControlContext_offset;
  static int _priority_offset;
  static int _eetop_offset;
  static int _daemon_offset;
  static int _stillborn_offset;
  static int _stackSize_offset;
  static int _tid_offset;
  static int _thread_status_offset;
  static int _park_blocker_offset;
  static int _park_event_offset ;

  static void compute_offsets();

 public:
  // Instance creation
  static oop create();
  // Returns the JavaThread associated with the thread obj
  static JavaThread* thread(oop java_thread);
  // Set JavaThread for instance
  static void set_thread(oop java_thread, JavaThread* thread);
  // Name
  static typeArrayOop name(oop java_thread);
  static void set_name(oop java_thread, typeArrayOop name);
  // Priority
  static ThreadPriority priority(oop java_thread);
  static void set_priority(oop java_thread, ThreadPriority priority);
  // Thread group
  static oop  threadGroup(oop java_thread);
  // Stillborn
  static bool is_stillborn(oop java_thread);
  static void set_stillborn(oop java_thread);
  // Alive (NOTE: this is not really a field, but provides the correct
  // definition without doing a Java call)
  static bool is_alive(oop java_thread);
  // Daemon
  static bool is_daemon(oop java_thread);
  static void set_daemon(oop java_thread);
  // Context ClassLoader
  static oop context_class_loader(oop java_thread);
  // Control context
  static oop inherited_access_control_context(oop java_thread);
  // Stack size hint
  static jlong stackSize(oop java_thread);
  // Thread ID
  static jlong thread_id(oop java_thread);

  // Blocker object responsible for thread parking
  static oop park_blocker(oop java_thread);

  // Pointer to type-stable park handler, encoded as jlong.
  // Should be set when apparently null
  // For details, see unsafe.cpp Unsafe_Unpark
  static jlong park_event(oop java_thread);
  static bool set_park_event(oop java_thread, jlong ptr);

  // Java Thread Status for JVMTI and M&M use.
  // This thread status info is saved in threadStatus field of
  // java.lang.Thread java class.
  enum ThreadStatus {
    NEW                      = 0,
    RUNNABLE                 = JVMTI_THREAD_STATE_ALIVE +          // runnable / running
                               JVMTI_THREAD_STATE_RUNNABLE,
    SLEEPING                 = JVMTI_THREAD_STATE_ALIVE +          // Thread.sleep()
                               JVMTI_THREAD_STATE_WAITING +
                               JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT +
                               JVMTI_THREAD_STATE_SLEEPING,
    IN_OBJECT_WAIT           = JVMTI_THREAD_STATE_ALIVE +          // Object.wait()
                               JVMTI_THREAD_STATE_WAITING +
                               JVMTI_THREAD_STATE_WAITING_INDEFINITELY +
                               JVMTI_THREAD_STATE_IN_OBJECT_WAIT,
    IN_OBJECT_WAIT_TIMED     = JVMTI_THREAD_STATE_ALIVE +          // Object.wait(long)
                               JVMTI_THREAD_STATE_WAITING +
                               JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT +
                               JVMTI_THREAD_STATE_IN_OBJECT_WAIT,
    PARKED                   = JVMTI_THREAD_STATE_ALIVE +          // LockSupport.park()
                               JVMTI_THREAD_STATE_WAITING +
                               JVMTI_THREAD_STATE_WAITING_INDEFINITELY +
                               JVMTI_THREAD_STATE_PARKED,
    PARKED_TIMED             = JVMTI_THREAD_STATE_ALIVE +          // LockSupport.park(long)
                               JVMTI_THREAD_STATE_WAITING +
                               JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT +
                               JVMTI_THREAD_STATE_PARKED,
    BLOCKED_ON_MONITOR_ENTER = JVMTI_THREAD_STATE_ALIVE +          // (re-)entering a synchronization block
                               JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER,
    TERMINATED               = JVMTI_THREAD_STATE_TERMINATED
  };
  // Write thread status info to threadStatus field of java.lang.Thread.
  static void set_thread_status(oop java_thread_oop, ThreadStatus status);
  // Read thread status info from threadStatus field of java.lang.Thread.
  static ThreadStatus get_thread_status(oop java_thread_oop);

  static const char*  thread_status_name(oop java_thread_oop);

  // Debugging
  friend class JavaClasses;
};

// Interface to java.lang.ThreadGroup objects

class java_lang_ThreadGroup : AllStatic {
 private:
  static int _parent_offset;
  static int _name_offset;
  static int _threads_offset;
  static int _groups_offset;
  static int _maxPriority_offset;
  static int _destroyed_offset;
  static int _daemon_offset;
  static int _vmAllowSuspension_offset;
  static int _nthreads_offset;
  static int _ngroups_offset;

  static void compute_offsets();

 public:
  // parent ThreadGroup
  static oop  parent(oop java_thread_group);
  // name
  static typeArrayOop name(oop java_thread_group);
  // ("name as oop" accessor is not necessary)
  // Number of threads in group
  static int nthreads(oop java_thread_group);
  // threads
  static objArrayOop threads(oop java_thread_group);
  // Number of threads in group
  static int ngroups(oop java_thread_group);
  // groups
  static objArrayOop groups(oop java_thread_group);
  // maxPriority in group
  static ThreadPriority maxPriority(oop java_thread_group);
  // Destroyed
  static bool is_destroyed(oop java_thread_group);
  // Daemon
  static bool is_daemon(oop java_thread_group);
  // vmAllowSuspension
  static bool is_vmAllowSuspension(oop java_thread_group);
  // Debugging
  friend class JavaClasses;
};



// Interface to java.lang.Throwable objects

class java_lang_Throwable: AllStatic {
  friend class BacktraceBuilder;

 private:
  // Offsets
  enum {
    hc_backtrace_offset     =  0,
    hc_detailMessage_offset =  1,
    hc_cause_offset         =  2,  // New since 1.4
    hc_stackTrace_offset    =  3   // New since 1.4
  };
  // Trace constants
  enum {
    trace_methods_offset = 0,
    trace_bcis_offset    = 1,
    trace_next_offset    = 2,
    trace_size           = 3,
    trace_chunk_size     = 32
  };

  static int backtrace_offset;
  static int detailMessage_offset;
  static int cause_offset;
  static int stackTrace_offset;

  // Printing
  static char* print_stack_element_to_buffer(methodOop method, int bci);
  static void print_to_stream(Handle stream, const char* str);
  // StackTrace (programmatic access, new since 1.4)
  static void clear_stacktrace(oop throwable);
  // No stack trace available
  static const char* no_stack_trace_message();

 public:
  // Backtrace
  static oop backtrace(oop throwable);
  static void set_backtrace(oop throwable, oop value);
  // Needed by JVMTI to filter out this internal field.
  static int get_backtrace_offset() { return backtrace_offset;}
  static int get_detailMessage_offset() { return detailMessage_offset;}
  // Message
  static oop message(oop throwable);
  static oop message(Handle throwable);
  static void set_message(oop throwable, oop value);
  // Print stack trace stored in exception by call-back to Java
  // Note: this is no longer used in Merlin, but we still suppport
  // it for compatibility.
  static void print_stack_trace(oop throwable, oop print_stream);
  static void print_stack_element(Handle stream, methodOop method, int bci);
  static void print_stack_element(outputStream *st, methodOop method, int bci);
  static void print_stack_usage(Handle stream);

  // Allocate space for backtrace (created but stack trace not filled in)
  static void allocate_backtrace(Handle throwable, TRAPS);
  // Fill in current stack trace for throwable with preallocated backtrace (no GC)
  static void fill_in_stack_trace_of_preallocated_backtrace(Handle throwable);

  // Fill in current stack trace, can cause GC
  static void fill_in_stack_trace(Handle throwable, TRAPS);
  static void fill_in_stack_trace(Handle throwable);
  // Programmatic access to stack trace
  static oop  get_stack_trace_element(oop throwable, int index, TRAPS);
  static int  get_stack_trace_depth(oop throwable, TRAPS);
  // Printing
  static void print(oop throwable, outputStream* st);
  static void print(Handle throwable, outputStream* st);
  static void print_stack_trace(oop throwable, outputStream* st);
  // Debugging
  friend class JavaClasses;
};


// Interface to java.lang.reflect.AccessibleObject objects

class java_lang_reflect_AccessibleObject: AllStatic {
 private:
  // Note that to reduce dependencies on the JDK we compute these
  // offsets at run-time.
  static int override_offset;

  static void compute_offsets();

 public:
  // Accessors
  static jboolean override(oop reflect);
  static void set_override(oop reflect, jboolean value);

  // Debugging
  friend class JavaClasses;
};


// Interface to java.lang.reflect.Method objects

class java_lang_reflect_Method : public java_lang_reflect_AccessibleObject {
 private:
  // Note that to reduce dependencies on the JDK we compute these
  // offsets at run-time.
  static int clazz_offset;
  static int name_offset;
  static int returnType_offset;
  static int parameterTypes_offset;
  static int exceptionTypes_offset;
  static int slot_offset;
  static int modifiers_offset;
  static int signature_offset;
  static int annotations_offset;
  static int parameter_annotations_offset;
  static int annotation_default_offset;

  static void compute_offsets();

 public:
  // Allocation
  static Handle create(TRAPS);

  // Accessors
  static oop clazz(oop reflect);
  static void set_clazz(oop reflect, oop value);

  static oop name(oop method);
  static void set_name(oop method, oop value);

  static oop return_type(oop method);
  static void set_return_type(oop method, oop value);

  static oop parameter_types(oop method);
  static void set_parameter_types(oop method, oop value);

  static oop exception_types(oop method);
  static void set_exception_types(oop method, oop value);

  static int slot(oop reflect);
  static void set_slot(oop reflect, int value);

  static int modifiers(oop method);
  static void set_modifiers(oop method, int value);

  static bool has_signature_field();
  static oop signature(oop method);
  static void set_signature(oop method, oop value);

  static bool has_annotations_field();
  static oop annotations(oop method);
  static void set_annotations(oop method, oop value);

  static bool has_parameter_annotations_field();
  static oop parameter_annotations(oop method);
  static void set_parameter_annotations(oop method, oop value);

  static bool has_annotation_default_field();
  static oop annotation_default(oop method);
  static void set_annotation_default(oop method, oop value);

  // Debugging
  friend class JavaClasses;
};


// Interface to java.lang.reflect.Constructor objects

class java_lang_reflect_Constructor : public java_lang_reflect_AccessibleObject {
 private:
  // Note that to reduce dependencies on the JDK we compute these
  // offsets at run-time.
  static int clazz_offset;
  static int parameterTypes_offset;
  static int exceptionTypes_offset;
  static int slot_offset;
  static int modifiers_offset;
  static int signature_offset;
  static int annotations_offset;
  static int parameter_annotations_offset;

  static void compute_offsets();

 public:
  // Allocation
  static Handle create(TRAPS);

  // Accessors
  static oop clazz(oop reflect);
  static void set_clazz(oop reflect, oop value);

  static oop parameter_types(oop constructor);
  static void set_parameter_types(oop constructor, oop value);

  static oop exception_types(oop constructor);
  static void set_exception_types(oop constructor, oop value);

  static int slot(oop reflect);
  static void set_slot(oop reflect, int value);

  static int modifiers(oop constructor);
  static void set_modifiers(oop constructor, int value);

  static bool has_signature_field();
  static oop signature(oop constructor);
  static void set_signature(oop constructor, oop value);

  static bool has_annotations_field();
  static oop annotations(oop constructor);
  static void set_annotations(oop constructor, oop value);

  static bool has_parameter_annotations_field();
  static oop parameter_annotations(oop method);
  static void set_parameter_annotations(oop method, oop value);

  // Debugging
  friend class JavaClasses;
};


// Interface to java.lang.reflect.Field objects

class java_lang_reflect_Field : public java_lang_reflect_AccessibleObject {
 private:
  // Note that to reduce dependencies on the JDK we compute these
  // offsets at run-time.
  static int clazz_offset;
  static int name_offset;
  static int type_offset;
  static int slot_offset;
  static int modifiers_offset;
  static int signature_offset;
  static int annotations_offset;

  static void compute_offsets();

 public:
  // Allocation
  static Handle create(TRAPS);

  // Accessors
  static oop clazz(oop reflect);
  static void set_clazz(oop reflect, oop value);

  static oop name(oop field);
  static void set_name(oop field, oop value);

  static oop type(oop field);
  static void set_type(oop field, oop value);

  static int slot(oop reflect);
  static void set_slot(oop reflect, int value);

  static int modifiers(oop field);
  static void set_modifiers(oop field, int value);

  static bool has_signature_field();
  static oop signature(oop constructor);
  static void set_signature(oop constructor, oop value);

  static bool has_annotations_field();
  static oop annotations(oop constructor);
  static void set_annotations(oop constructor, oop value);

  static bool has_parameter_annotations_field();
  static oop parameter_annotations(oop method);
  static void set_parameter_annotations(oop method, oop value);

  static bool has_annotation_default_field();
  static oop annotation_default(oop method);
  static void set_annotation_default(oop method, oop value);

  // Debugging
  friend class JavaClasses;
};

// Interface to sun.reflect.ConstantPool objects
class sun_reflect_ConstantPool {
 private:
  // Note that to reduce dependencies on the JDK we compute these
  // offsets at run-time.
  static int _cp_oop_offset;

  static void compute_offsets();

 public:
  // Allocation
  static Handle create(TRAPS);

  // Accessors
  static oop cp_oop(oop reflect);
  static void set_cp_oop(oop reflect, oop value);
  static int cp_oop_offset() {
    return _cp_oop_offset;
  }

  // Debugging
  friend class JavaClasses;
};

// Interface to sun.reflect.UnsafeStaticFieldAccessorImpl objects
class sun_reflect_UnsafeStaticFieldAccessorImpl {
 private:
  static int _base_offset;
  static void compute_offsets();

 public:
  static int base_offset() {
    return _base_offset;
  }

  // Debugging
  friend class JavaClasses;
};

// Interface to java.lang primitive type boxing objects:
//  - java.lang.Boolean
//  - java.lang.Character
//  - java.lang.Float
//  - java.lang.Double
//  - java.lang.Byte
//  - java.lang.Short
//  - java.lang.Integer
//  - java.lang.Long

// This could be separated out into 8 individual classes.

class java_lang_boxing_object: AllStatic {
 private:
  enum {
   hc_value_offset = 0
  };
  static int value_offset;
  static int long_value_offset;

  static oop initialize_and_allocate(BasicType type, TRAPS);
 public:
  // Allocation. Returns a boxed value, or NULL for invalid type.
  static oop create(BasicType type, jvalue* value, TRAPS);
  // Accessors. Returns the basic type being boxed, or T_ILLEGAL for invalid oop.
  static BasicType get_value(oop box, jvalue* value);
  static BasicType set_value(oop box, jvalue* value);
  static BasicType basic_type(oop box);
  static bool is_instance(oop box)                 { return basic_type(box) != T_ILLEGAL; }
  static bool is_instance(oop box, BasicType type) { return basic_type(box) == type; }
  static void print(oop box, outputStream* st)     { jvalue value;  print(get_value(box, &value), &value, st); }
  static void print(BasicType type, jvalue* value, outputStream* st);

  static int value_offset_in_bytes(BasicType type) {
    return ( type == T_LONG || type == T_DOUBLE ) ? long_value_offset :
                                                    value_offset;
  }

  // Debugging
  friend class JavaClasses;
};



// Interface to java.lang.ref.Reference objects

class java_lang_ref_Reference: AllStatic {
 public:
  enum {
   hc_referent_offset   = 0,
   hc_queue_offset      = 1,
   hc_next_offset       = 2,
   hc_discovered_offset = 3  // Is not last, see SoftRefs.
  };
  enum {
   hc_static_lock_offset    = 0,
   hc_static_pending_offset = 1
  };

  static int referent_offset;
  static int queue_offset;
  static int next_offset;
  static int discovered_offset;
  static int static_lock_offset;
  static int static_pending_offset;
  static int number_of_fake_oop_fields;

  // Accessors
  static oop referent(oop ref) {
    return ref->obj_field(referent_offset);
  }
  static void set_referent(oop ref, oop value) {
    ref->obj_field_put(referent_offset, value);
  }
  static void set_referent_raw(oop ref, oop value) {
    ref->obj_field_raw_put(referent_offset, value);
  }
  static HeapWord* referent_addr(oop ref) {
    return ref->obj_field_addr<HeapWord>(referent_offset);
  }
  static oop next(oop ref) {
    return ref->obj_field(next_offset);
  }
  static void set_next(oop ref, oop value) {
    ref->obj_field_put(next_offset, value);
  }
  static void set_next_raw(oop ref, oop value) {
    ref->obj_field_raw_put(next_offset, value);
  }
  static HeapWord* next_addr(oop ref) {
    return ref->obj_field_addr<HeapWord>(next_offset);
  }
  static oop discovered(oop ref) {
    return ref->obj_field(discovered_offset);
  }
  static void set_discovered(oop ref, oop value) {
    ref->obj_field_put(discovered_offset, value);
  }
  static void set_discovered_raw(oop ref, oop value) {
    ref->obj_field_raw_put(discovered_offset, value);
  }
  static HeapWord* discovered_addr(oop ref) {
    return ref->obj_field_addr<HeapWord>(discovered_offset);
  }
  // Accessors for statics
  static oop  pending_list_lock();
  static oop  pending_list();

  static HeapWord*  pending_list_addr();
};


// Interface to java.lang.ref.SoftReference objects

class java_lang_ref_SoftReference: public java_lang_ref_Reference {
 public:
  enum {
   // The timestamp is a long field and may need to be adjusted for alignment.
   hc_timestamp_offset  = hc_discovered_offset + 1
  };
  enum {
   hc_static_clock_offset = 0
  };

  static int timestamp_offset;
  static int static_clock_offset;

  // Accessors
  static jlong timestamp(oop ref);

  // Accessors for statics
  static jlong clock();
  static void set_clock(jlong value);
};


// Interface to java.dyn.MethodHandle objects

class MethodHandleEntry;

class java_dyn_MethodHandle: AllStatic {
  friend class JavaClasses;

 private:
  static int _vmentry_offset;           // assembly code trampoline for MH
  static int _vmtarget_offset;          // class-specific target reference
  static int _type_offset;              // the MethodType of this MH
  static int _vmslots_offset;           // OPTIONAL hoisted type.form.vmslots

  static void compute_offsets();

 public:
  // Accessors
  static oop            type(oop mh);
  static void       set_type(oop mh, oop mtype);

  static oop            vmtarget(oop mh);
  static void       set_vmtarget(oop mh, oop target);

  static MethodHandleEntry* vmentry(oop mh);
  static void       set_vmentry(oop mh, MethodHandleEntry* data);

  static int            vmslots(oop mh);
  static void      init_vmslots(oop mh);
  static int    compute_vmslots(oop mh);

  // Testers
  static bool is_subclass(klassOop klass) {
    return Klass::cast(klass)->is_subclass_of(SystemDictionary::MethodHandle_klass());
  }
  static bool is_instance(oop obj) {
    return obj != NULL && is_subclass(obj->klass());
  }

  // Accessors for code generation:
  static int type_offset_in_bytes()             { return _type_offset; }
  static int vmtarget_offset_in_bytes()         { return _vmtarget_offset; }
  static int vmentry_offset_in_bytes()          { return _vmentry_offset; }
  static int vmslots_offset_in_bytes()          { return _vmslots_offset; }
};

class sun_dyn_DirectMethodHandle: public java_dyn_MethodHandle {
  friend class JavaClasses;

 private:
  //         _vmtarget_offset;          // method   or class      or interface
  static int _vmindex_offset;           // negative or vtable idx or itable idx
  static void compute_offsets();

 public:
  // Accessors
  static int            vmindex(oop mh);
  static void       set_vmindex(oop mh, int index);

  // Testers
  static bool is_subclass(klassOop klass) {
    return Klass::cast(klass)->is_subclass_of(SystemDictionary::DirectMethodHandle_klass());
  }
  static bool is_instance(oop obj) {
    return obj != NULL && is_subclass(obj->klass());
  }

  // Accessors for code generation:
  static int vmindex_offset_in_bytes()          { return _vmindex_offset; }
};

class sun_dyn_BoundMethodHandle: public java_dyn_MethodHandle {
  friend class JavaClasses;

 private:
  static int _argument_offset;          // argument value bound into this MH
  static int _vmargslot_offset;         // relevant argument slot (<= vmslots)
  static void compute_offsets();

public:
  static oop            argument(oop mh);
  static void       set_argument(oop mh, oop ref);

  static jint           vmargslot(oop mh);
  static void       set_vmargslot(oop mh, jint slot);

  // Testers
  static bool is_subclass(klassOop klass) {
    return Klass::cast(klass)->is_subclass_of(SystemDictionary::BoundMethodHandle_klass());
  }
  static bool is_instance(oop obj) {
    return obj != NULL && is_subclass(obj->klass());
  }

  static int argument_offset_in_bytes()         { return _argument_offset; }
  static int vmargslot_offset_in_bytes()        { return _vmargslot_offset; }
};

class sun_dyn_AdapterMethodHandle: public sun_dyn_BoundMethodHandle {
  friend class JavaClasses;

 private:
  static int _conversion_offset;        // type of conversion to apply
  static void compute_offsets();

 public:
  static int            conversion(oop mh);
  static void       set_conversion(oop mh, int conv);

  // Testers
  static bool is_subclass(klassOop klass) {
    return Klass::cast(klass)->is_subclass_of(SystemDictionary::AdapterMethodHandle_klass());
  }
  static bool is_instance(oop obj) {
    return obj != NULL && is_subclass(obj->klass());
  }

  // Relevant integer codes (keep these in synch. with MethodHandleNatives.Constants):
  enum {
    OP_RETYPE_ONLY   = 0x0, // no argument changes; straight retype
    OP_RETYPE_RAW    = 0x1, // straight retype, trusted (void->int, Object->T)
    OP_CHECK_CAST    = 0x2, // ref-to-ref conversion; requires a Class argument
    OP_PRIM_TO_PRIM  = 0x3, // converts from one primitive to another
    OP_REF_TO_PRIM   = 0x4, // unboxes a wrapper to produce a primitive
    OP_PRIM_TO_REF   = 0x5, // boxes a primitive into a wrapper (NYI)
    OP_SWAP_ARGS     = 0x6, // swap arguments (vminfo is 2nd arg)
    OP_ROT_ARGS      = 0x7, // rotate arguments (vminfo is displaced arg)
    OP_DUP_ARGS      = 0x8, // duplicates one or more arguments (at TOS)
    OP_DROP_ARGS     = 0x9, // remove one or more argument slots
    OP_COLLECT_ARGS  = 0xA, // combine one or more arguments into a varargs (NYI)
    OP_SPREAD_ARGS   = 0xB, // expand in place a varargs array (of known size)
    OP_FLYBY         = 0xC, // operate first on reified argument list (NYI)
    OP_RICOCHET      = 0xD, // run an adapter chain on the return value (NYI)
    CONV_OP_LIMIT    = 0xE, // limit of CONV_OP enumeration

    CONV_OP_MASK     = 0xF00, // this nybble contains the conversion op field
    CONV_VMINFO_MASK = 0x0FF, // LSB is reserved for JVM use
    CONV_VMINFO_SHIFT     =  0, // position of bits in CONV_VMINFO_MASK
    CONV_OP_SHIFT         =  8, // position of bits in CONV_OP_MASK
    CONV_DEST_TYPE_SHIFT  = 12, // byte 2 has the adapter BasicType (if needed)
    CONV_SRC_TYPE_SHIFT   = 16, // byte 2 has the source BasicType (if needed)
    CONV_STACK_MOVE_SHIFT = 20, // high 12 bits give signed SP change
    CONV_STACK_MOVE_MASK  = (1 << (32 - CONV_STACK_MOVE_SHIFT)) - 1
  };

  static int conversion_offset_in_bytes()       { return _conversion_offset; }
};


// Interface to sun.dyn.MemberName objects
// (These are a private interface for Java code to query the class hierarchy.)

class sun_dyn_MemberName: AllStatic {
  friend class JavaClasses;

 private:
  // From java.dyn.MemberName:
  //    private Class<?>   clazz;       // class in which the method is defined
  //    private String     name;        // may be null if not yet materialized
  //    private Object     type;        // may be null if not yet materialized
  //    private int        flags;       // modifier bits; see reflect.Modifier
  //    private Object     vmtarget;    // VM-specific target value
  //    private int        vmindex;     // method index within class or interface
  static int _clazz_offset;
  static int _name_offset;
  static int _type_offset;
  static int _flags_offset;
  static int _vmtarget_offset;
  static int _vmindex_offset;

  static void compute_offsets();

 public:
  // Accessors
  static oop            clazz(oop mname);
  static void       set_clazz(oop mname, oop clazz);

  static oop            type(oop mname);
  static void       set_type(oop mname, oop type);

  static oop            name(oop mname);
  static void       set_name(oop mname, oop name);

  static int            flags(oop mname);
  static void       set_flags(oop mname, int flags);

  static int            modifiers(oop mname) { return (u2) flags(mname); }
  static void       set_modifiers(oop mname, int mods)
                                { set_flags(mname, (flags(mname) &~ (u2)-1) | (u2)mods); }

  static oop            vmtarget(oop mname);
  static void       set_vmtarget(oop mname, oop target);

  static int            vmindex(oop mname);
  static void       set_vmindex(oop mname, int index);

  // Testers
  static bool is_subclass(klassOop klass) {
    return Klass::cast(klass)->is_subclass_of(SystemDictionary::MemberName_klass());
  }
  static bool is_instance(oop obj) {
    return obj != NULL && is_subclass(obj->klass());
  }

  // Relevant integer codes (keep these in synch. with MethodHandleNatives.Constants):
  enum {
    MN_IS_METHOD           = 0x00010000, // method (not constructor)
    MN_IS_CONSTRUCTOR      = 0x00020000, // constructor
    MN_IS_FIELD            = 0x00040000, // field
    MN_IS_TYPE             = 0x00080000, // nested type
    MN_SEARCH_SUPERCLASSES = 0x00100000, // for MHN.getMembers
    MN_SEARCH_INTERFACES   = 0x00200000, // for MHN.getMembers
    VM_INDEX_UNINITIALIZED = -99
  };

  // Accessors for code generation:
  static int clazz_offset_in_bytes()            { return _clazz_offset; }
  static int type_offset_in_bytes()             { return _type_offset; }
  static int name_offset_in_bytes()             { return _name_offset; }
  static int flags_offset_in_bytes()            { return _flags_offset; }
  static int vmtarget_offset_in_bytes()         { return _vmtarget_offset; }
  static int vmindex_offset_in_bytes()          { return _vmindex_offset; }
};


// Interface to java.dyn.MethodType objects

class java_dyn_MethodType: AllStatic {
  friend class JavaClasses;

 private:
  static int _rtype_offset;
  static int _ptypes_offset;
  static int _form_offset;

  static void compute_offsets();

 public:
  // Accessors
  static oop            rtype(oop mt);
  static objArrayOop    ptypes(oop mt);
  static oop            form(oop mt);

  static oop            ptype(oop mt, int index);

  static symbolOop      as_signature(oop mt, bool intern_if_not_found, TRAPS);
  static void           print_signature(oop mt, outputStream* st);

  static bool is_instance(oop obj) {
    return obj != NULL && obj->klass() == SystemDictionary::MethodType_klass();
  }

  // Accessors for code generation:
  static int rtype_offset_in_bytes()            { return _rtype_offset; }
  static int ptypes_offset_in_bytes()           { return _ptypes_offset; }
  static int form_offset_in_bytes()             { return _form_offset; }
};

class java_dyn_MethodTypeForm: AllStatic {
  friend class JavaClasses;

 private:
  static int _vmslots_offset;           // number of argument slots needed
  static int _erasedType_offset;        // erasedType = canonical MethodType

  static void compute_offsets();

 public:
  // Accessors
  static int            vmslots(oop mtform);
  static oop            erasedType(oop mtform);

  // Accessors for code generation:
  static int vmslots_offset_in_bytes()          { return _vmslots_offset; }
  static int erasedType_offset_in_bytes()       { return _erasedType_offset; }
};


// Interface to sun.dyn.CallSiteImpl objects

class sun_dyn_CallSiteImpl: AllStatic {
  friend class JavaClasses;

private:
  static int _type_offset;
  static int _target_offset;
  static int _vmmethod_offset;

  static void compute_offsets();

public:
  // Accessors
  static oop            type(oop site);

  static oop            target(oop site);
  static void       set_target(oop site, oop target);

  static oop            vmmethod(oop site);
  static void       set_vmmethod(oop site, oop ref);

  // Accessors for code generation:
  static int target_offset_in_bytes()           { return _target_offset; }
  static int type_offset_in_bytes()             { return _type_offset; }
  static int vmmethod_offset_in_bytes()         { return _vmmethod_offset; }
};


// Interface to java.security.AccessControlContext objects

class java_security_AccessControlContext: AllStatic {
 private:
  // Note that for this class the layout changed between JDK1.2 and JDK1.3,
  // so we compute the offsets at startup rather than hard-wiring them.
  static int _context_offset;
  static int _privilegedContext_offset;
  static int _isPrivileged_offset;

  static void compute_offsets();
 public:
  static oop create(objArrayHandle context, bool isPrivileged, Handle privileged_context, TRAPS);

  // Debugging/initialization
  friend class JavaClasses;
};


// Interface to java.lang.ClassLoader objects

class java_lang_ClassLoader : AllStatic {
 private:
  enum {
   hc_parent_offset = 0
  };

  static int parent_offset;

 public:
  static oop parent(oop loader);

  static bool is_trusted_loader(oop loader);

  // Fix for 4474172
  static oop  non_reflection_class_loader(oop loader);

  // Debugging
  friend class JavaClasses;
};


// Interface to java.lang.System objects

class java_lang_System : AllStatic {
 private:
  enum {
   hc_static_in_offset  = 0,
   hc_static_out_offset = 1,
   hc_static_err_offset = 2
  };

  static int offset_of_static_fields;
  static int  static_in_offset;
  static int static_out_offset;
  static int static_err_offset;

  static void compute_offsets();

 public:
  static int  in_offset_in_bytes();
  static int out_offset_in_bytes();
  static int err_offset_in_bytes();

  // Debugging
  friend class JavaClasses;
};


// Interface to java.lang.StackTraceElement objects

class java_lang_StackTraceElement: AllStatic {
 private:
  enum {
    hc_declaringClass_offset  = 0,
    hc_methodName_offset = 1,
    hc_fileName_offset   = 2,
    hc_lineNumber_offset = 3
  };

  static int declaringClass_offset;
  static int methodName_offset;
  static int fileName_offset;
  static int lineNumber_offset;

 public:
  // Setters
  static void set_declaringClass(oop element, oop value);
  static void set_methodName(oop element, oop value);
  static void set_fileName(oop element, oop value);
  static void set_lineNumber(oop element, int value);

  // Create an instance of StackTraceElement
  static oop create(methodHandle m, int bci, TRAPS);

  // Debugging
  friend class JavaClasses;
};


// Interface to java.lang.AssertionStatusDirectives objects

class java_lang_AssertionStatusDirectives: AllStatic {
 private:
  enum {
    hc_classes_offset,
    hc_classEnabled_offset,
    hc_packages_offset,
    hc_packageEnabled_offset,
    hc_deflt_offset
  };

  static int classes_offset;
  static int classEnabled_offset;
  static int packages_offset;
  static int packageEnabled_offset;
  static int deflt_offset;

 public:
  // Setters
  static void set_classes(oop obj, oop val);
  static void set_classEnabled(oop obj, oop val);
  static void set_packages(oop obj, oop val);
  static void set_packageEnabled(oop obj, oop val);
  static void set_deflt(oop obj, bool val);
  // Debugging
  friend class JavaClasses;
};


class java_nio_Buffer: AllStatic {
 private:
  static int _limit_offset;

 public:
  static int  limit_offset();
  static void compute_offsets();
};

class sun_misc_AtomicLongCSImpl: AllStatic {
 private:
  static int _value_offset;

 public:
  static int  value_offset();
  static void compute_offsets();
};

class java_util_concurrent_locks_AbstractOwnableSynchronizer : AllStatic {
 private:
  static int  _owner_offset;
 public:
  static void initialize(TRAPS);
  static oop  get_owner_threadObj(oop obj);
};

// Interface to hard-coded offset checking

class JavaClasses : AllStatic {
 private:
  static bool check_offset(const char *klass_name, int offset, const char *field_name, const char* field_sig) PRODUCT_RETURN0;
  static bool check_static_offset(const char *klass_name, int hardcoded_offset, const char *field_name, const char* field_sig) PRODUCT_RETURN0;
  static bool check_constant(const char *klass_name, int constant, const char *field_name, const char* field_sig) PRODUCT_RETURN0;
 public:
  static void compute_hard_coded_offsets();
  static void compute_offsets();
  static void check_offsets() PRODUCT_RETURN;
};