jdk8-mips64-public/hotspot: src/share/vm/oops/klass.hpp@94ec88ca68e2 (annotated)

src/share/vm/oops/klass.hpp@94ec88ca68e2 (annotated)

src/share/vm/oops/klass.hpp

Wed, 11 Jan 2012 17:34:02 -0500

author: phh
date: Wed, 11 Jan 2012 17:34:02 -0500
changeset 3427: 94ec88ca68e2
parent 2658: c7f3d0b4570f
child 3428: 4f3ce9284781
permissions: -rw-r--r--

7115199: Add event tracing hooks and Java Flight Recorder infrastructure
Summary: Added a nop tracing infrastructure, JFR makefile changes and other infrastructure used only by JFR.
Reviewed-by: acorn, sspitsyn
Contributed-by: markus.gronlund@oracle.com

 /*
  * Copyright (c) 1997, 2011, 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.
  *
  */
 #ifndef SHARE_VM_OOPS_KLASS_HPP
 #define SHARE_VM_OOPS_KLASS_HPP
 #include "memory/genOopClosures.hpp"
 #include "memory/iterator.hpp"
 #include "memory/memRegion.hpp"
 #include "memory/specialized_oop_closures.hpp"
 #include "oops/klassOop.hpp"
 #include "oops/klassPS.hpp"
 #include "oops/oop.hpp"
 #include "runtime/orderAccess.hpp"
 #include "trace/traceMacros.hpp"
 #include "utilities/accessFlags.hpp"
 #ifndef SERIALGC
 #include "gc_implementation/concurrentMarkSweep/cmsOopClosures.hpp"
 #include "gc_implementation/g1/g1OopClosures.hpp"
 #include "gc_implementation/parNew/parOopClosures.hpp"
 #endif
 // A Klass is the part of the klassOop that provides:
 //  1: language level class object (method dictionary etc.)
 //  2: provide vm dispatch behavior for the object
 // Both functions are combined into one C++ class. The toplevel class "Klass"
 // implements purpose 1 whereas all subclasses provide extra virtual functions
 // for purpose 2.
 // One reason for the oop/klass dichotomy in the implementation is
 // that we don't want a C++ vtbl pointer in every object.  Thus,
 // normal oops don't have any virtual functions.  Instead, they
 // forward all "virtual" functions to their klass, which does have
 // a vtbl and does the C++ dispatch depending on the object's
 // actual type.  (See oop.inline.hpp for some of the forwarding code.)
 // ALL FUNCTIONS IMPLEMENTING THIS DISPATCH ARE PREFIXED WITH "oop_"!
 //  Klass layout:
 //    [header        ] klassOop
 //    [klass pointer ] klassOop
 //    [C++ vtbl ptr  ] (contained in Klass_vtbl)
 //    [layout_helper ]
 //    [super_check_offset   ] for fast subtype checks
 //    [secondary_super_cache] for fast subtype checks
 //    [secondary_supers     ] array of 2ndary supertypes
 //    [primary_supers 0]
 //    [primary_supers 1]
 //    [primary_supers 2]
 //    ...
 //    [primary_supers 7]
 //    [java_mirror   ]
 //    [super         ]
 //    [name          ]
 //    [first subklass]
 //    [next_sibling  ] link to chain additional subklasses
 //    [modifier_flags]
 //    [access_flags  ]
 //    [verify_count  ] - not in product
 //    [alloc_count   ]
 //    [last_biased_lock_bulk_revocation_time] (64 bits)
 //    [prototype_header]
 //    [biased_lock_revocation_count]
 //    [trace_id]
 // Forward declarations.
 class klassVtable;
 class KlassHandle;
 class OrderAccess;
 // Holder (or cage) for the C++ vtable of each kind of Klass.
 // We want to tightly constrain the location of the C++ vtable in the overall layout.
 class Klass_vtbl {
  protected:
   // The following virtual exists only to force creation of a C++ vtable,
   // so that this class truly is the location of the vtable of all Klasses.
   virtual void unused_initial_virtual() { }
  public:
   // The following virtual makes Klass_vtbl play a second role as a
   // factory protocol for subclasses of Klass ("sub-Klasses").
   // Here's how it works....
   //
   // This VM uses metaobjects as factories for their instances.
   //
   // In order to initialize the C++ vtable of a new instance, its
   // metaobject is forced to use the C++ placed new operator to
   // allocate the instance.  In a typical C++-based system, each
   // sub-class would have its own factory routine which
   // directly uses the placed new operator on the desired class,
   // and then calls the appropriate chain of C++ constructors.
   //
   // However, this system uses shared code to performs the first
   // allocation and initialization steps for all sub-Klasses.
   // (See base_create_klass() and base_create_array_klass().)
   // This does not factor neatly into a hierarchy of C++ constructors.
   // Each caller of these shared "base_create" routines knows
   // exactly which sub-Klass it is creating, but the shared routine
   // does not, even though it must perform the actual allocation.
   //
   // Therefore, the caller of the shared "base_create" must wrap
   // the specific placed new call in a virtual function which
   // performs the actual allocation and vtable set-up.  That
   // virtual function is here, Klass_vtbl::allocate_permanent.
   //
   // The arguments to Universe::allocate_permanent() are passed
   // straight through the placed new operator, which in turn
   // obtains them directly from this virtual call.
   //
   // This virtual is called on a temporary "example instance" of the
   // sub-Klass being instantiated, a C++ auto variable.  The "real"
   // instance created by this virtual is on the VM heap, where it is
   // equipped with a klassOopDesc header.
   //
   // It is merely an accident of implementation that we use "example
   // instances", but that is why the virtual function which implements
   // each sub-Klass factory happens to be defined by the same sub-Klass
   // for which it creates instances.
   //
   // The vtbl_value() call (see below) is used to strip away the
   // accidental Klass-ness from an "example instance" and present it as
   // a factory.  Think of each factory object as a mere container of the
   // C++ vtable for the desired sub-Klass.  Since C++ does not allow
   // direct references to vtables, the factory must also be delegated
   // the task of allocating the instance, but the essential point is
   // that the factory knows how to initialize the C++ vtable with the
   // right pointer value.  All other common initializations are handled
   // by the shared "base_create" subroutines.
   //
   virtual void* allocate_permanent(KlassHandle& klass, int size, TRAPS) const = 0;
   void post_new_init_klass(KlassHandle& klass, klassOop obj, int size) const;
   // Every subclass on which vtbl_value is called must include this macro.
   // Delay the installation of the klassKlass pointer until after the
   // the vtable for a new klass has been installed (after the call to new()).
 #define DEFINE_ALLOCATE_PERMANENT(thisKlass)                                  \
   void* allocate_permanent(KlassHandle& klass_klass, int size, TRAPS) const { \
     void* result = new(klass_klass, size, THREAD) thisKlass();                \
     if (HAS_PENDING_EXCEPTION) return NULL;                                   \
     klassOop new_klass = ((Klass*) result)->as_klassOop();                    \
     OrderAccess::storestore();                                                \
     post_new_init_klass(klass_klass, new_klass, size);                        \
     return result;                                                            \
   }
   bool null_vtbl() { return *(intptr_t*)this == 0; }
  protected:
   void* operator new(size_t ignored, KlassHandle& klass, int size, TRAPS);
 };
 class Klass : public Klass_vtbl {
   friend class VMStructs;
  protected:
   // note: put frequently-used fields together at start of klass structure
   // for better cache behavior (may not make much of a difference but sure won't hurt)
   enum { _primary_super_limit = 8 };
   // The "layout helper" is a combined descriptor of object layout.
   // For klasses which are neither instance nor array, the value is zero.
   //
   // For instances, layout helper is a positive number, the instance size.
   // This size is already passed through align_object_size and scaled to bytes.
   // The low order bit is set if instances of this class cannot be
   // allocated using the fastpath.
   //
   // For arrays, layout helper is a negative number, containing four
   // distinct bytes, as follows:
   //    MSB:[tag, hsz, ebt, log2(esz)]:LSB
   // where:
   //    tag is 0x80 if the elements are oops, 0xC0 if non-oops
   //    hsz is array header size in bytes (i.e., offset of first element)
   //    ebt is the BasicType of the elements
   //    esz is the element size in bytes
   // This packed word is arranged so as to be quickly unpacked by the
   // various fast paths that use the various subfields.
   //
   // The esz bits can be used directly by a SLL instruction, without masking.
   //
   // Note that the array-kind tag looks like 0x00 for instance klasses,
   // since their length in bytes is always less than 24Mb.
   //
   // Final note:  This comes first, immediately after Klass_vtbl,
   // because it is frequently queried.
   jint        _layout_helper;
   // The fields _super_check_offset, _secondary_super_cache, _secondary_supers
   // and _primary_supers all help make fast subtype checks.  See big discussion
   // in doc/server_compiler/checktype.txt
   //
   // Where to look to observe a supertype (it is &_secondary_super_cache for
   // secondary supers, else is &_primary_supers[depth()].
   juint       _super_check_offset;
   // Class name.  Instance classes: java/lang/String, etc.  Array classes: [I,
   // [Ljava/lang/String;, etc.  Set to zero for all other kinds of classes.
   Symbol*     _name;
  public:
   oop* oop_block_beg() const { return adr_secondary_super_cache(); }
   oop* oop_block_end() const { return adr_next_sibling() + 1; }
  protected:
   //
   // The oop block.  All oop fields must be declared here and only oop fields
   // may be declared here.  In addition, the first and last fields in this block
   // must remain first and last, unless oop_block_beg() and/or oop_block_end()
   // are updated.  Grouping the oop fields in a single block simplifies oop
   // iteration.
   //
   // Cache of last observed secondary supertype
   klassOop    _secondary_super_cache;
   // Array of all secondary supertypes
   objArrayOop _secondary_supers;
   // Ordered list of all primary supertypes
   klassOop    _primary_supers[_primary_super_limit];
   // java/lang/Class instance mirroring this class
   oop       _java_mirror;
   // Superclass
   klassOop  _super;
   // First subclass (NULL if none); _subklass->next_sibling() is next one
   klassOop _subklass;
   // Sibling link (or NULL); links all subklasses of a klass
   klassOop _next_sibling;
   //
   // End of the oop block.
   //
   jint        _modifier_flags;  // Processed access flags, for use by Class.getModifiers.
   AccessFlags _access_flags;    // Access flags. The class/interface distinction is stored here.
 #ifndef PRODUCT
   int           _verify_count;  // to avoid redundant verifies
 #endif
   juint    _alloc_count;        // allocation profiling support - update klass_size_in_bytes() if moved/deleted
   // Biased locking implementation and statistics
   // (the 64-bit chunk goes first, to avoid some fragmentation)
   jlong    _last_biased_lock_bulk_revocation_time;
   markOop  _prototype_header;   // Used when biased locking is both enabled and disabled for this type
   jint     _biased_lock_revocation_count;
 #ifdef TRACE_DEFINE_KLASS_TRACE_ID
   TRACE_DEFINE_KLASS_TRACE_ID;
 #endif
  public:
   // returns the enclosing klassOop
   klassOop as_klassOop() const {
     // see klassOop.hpp for layout.
     return (klassOop) (((char*) this) - sizeof(klassOopDesc));
   }
  public:
   // Allocation
   const Klass_vtbl& vtbl_value() const { return *this; }  // used only on "example instances"
   static KlassHandle base_create_klass(KlassHandle& klass, int size, const Klass_vtbl& vtbl, TRAPS);
   static klassOop base_create_klass_oop(KlassHandle& klass, int size, const Klass_vtbl& vtbl, TRAPS);
   // super
   klassOop super() const               { return _super; }
   void set_super(klassOop k)           { oop_store_without_check((oop*) &_super, (oop) k); }
   // initializes _super link, _primary_supers & _secondary_supers arrays
   void initialize_supers(klassOop k, TRAPS);
   void initialize_supers_impl1(klassOop k);
   void initialize_supers_impl2(klassOop k);
   // klass-specific helper for initializing _secondary_supers
   virtual objArrayOop compute_secondary_supers(int num_extra_slots, TRAPS);
   // java_super is the Java-level super type as specified by Class.getSuperClass.
   virtual klassOop java_super() const  { return NULL; }
   juint    super_check_offset() const  { return _super_check_offset; }
   void set_super_check_offset(juint o) { _super_check_offset = o; }
   klassOop secondary_super_cache() const     { return _secondary_super_cache; }
   void set_secondary_super_cache(klassOop k) { oop_store_without_check((oop*) &_secondary_super_cache, (oop) k); }
   objArrayOop secondary_supers() const { return _secondary_supers; }
   void set_secondary_supers(objArrayOop k) { oop_store_without_check((oop*) &_secondary_supers, (oop) k); }
   // Return the element of the _super chain of the given depth.
   // If there is no such element, return either NULL or this.
   klassOop primary_super_of_depth(juint i) const {
     assert(i < primary_super_limit(), "oob");
     klassOop super = _primary_supers[i];
     assert(super == NULL || super->klass_part()->super_depth() == i, "correct display");
     return super;
   }
   // Can this klass be a primary super?  False for interfaces and arrays of
   // interfaces.  False also for arrays or classes with long super chains.
   bool can_be_primary_super() const {
     const juint secondary_offset = secondary_super_cache_offset_in_bytes() + sizeof(oopDesc);
     return super_check_offset() != secondary_offset;
   }
   virtual bool can_be_primary_super_slow() const;
   // Returns number of primary supers; may be a number in the inclusive range [0, primary_super_limit].
   juint super_depth() const {
     if (!can_be_primary_super()) {
       return primary_super_limit();
     } else {
       juint d = (super_check_offset() - (primary_supers_offset_in_bytes() + sizeof(oopDesc))) / sizeof(klassOop);
       assert(d < primary_super_limit(), "oob");
       assert(_primary_supers[d] == as_klassOop(), "proper init");
       return d;
     }
   }
   // java mirror
   oop java_mirror() const              { return _java_mirror; }
   void set_java_mirror(oop m)          { oop_store((oop*) &_java_mirror, m); }
   // modifier flags
   jint modifier_flags() const          { return _modifier_flags; }
   void set_modifier_flags(jint flags)  { _modifier_flags = flags; }
   // size helper
   int layout_helper() const            { return _layout_helper; }
   void set_layout_helper(int lh)       { _layout_helper = lh; }
   // Note: for instances layout_helper() may include padding.
   // Use instanceKlass::contains_field_offset to classify field offsets.
   // sub/superklass links
   instanceKlass* superklass() const;
   Klass* subklass() const;
   Klass* next_sibling() const;
   void append_to_sibling_list();           // add newly created receiver to superklass' subklass list
   void remove_from_sibling_list();         // remove receiver from sibling list
  protected:                                // internal accessors
   klassOop subklass_oop() const            { return _subklass; }
   klassOop next_sibling_oop() const        { return _next_sibling; }
   void     set_subklass(klassOop s);
   void     set_next_sibling(klassOop s);
   oop* adr_super()           const { return (oop*)&_super;             }
   oop* adr_primary_supers()  const { return (oop*)&_primary_supers[0]; }
   oop* adr_secondary_super_cache() const { return (oop*)&_secondary_super_cache; }
   oop* adr_secondary_supers()const { return (oop*)&_secondary_supers;  }
   oop* adr_java_mirror()     const { return (oop*)&_java_mirror;       }
   oop* adr_subklass()        const { return (oop*)&_subklass;          }
   oop* adr_next_sibling()    const { return (oop*)&_next_sibling;      }
  public:
   // Allocation profiling support
   juint alloc_count() const          { return _alloc_count; }
   void set_alloc_count(juint n)      { _alloc_count = n; }
   virtual juint alloc_size() const = 0;
   virtual void set_alloc_size(juint n) = 0;
   // Compiler support
   static int super_offset_in_bytes()         { return offset_of(Klass, _super); }
   static int super_check_offset_offset_in_bytes() { return offset_of(Klass, _super_check_offset); }
   static int primary_supers_offset_in_bytes(){ return offset_of(Klass, _primary_supers); }
   static int secondary_super_cache_offset_in_bytes() { return offset_of(Klass, _secondary_super_cache); }
   static int secondary_supers_offset_in_bytes() { return offset_of(Klass, _secondary_supers); }
   static int java_mirror_offset_in_bytes()   { return offset_of(Klass, _java_mirror); }
   static int modifier_flags_offset_in_bytes(){ return offset_of(Klass, _modifier_flags); }
   static int layout_helper_offset_in_bytes() { return offset_of(Klass, _layout_helper); }
   static int access_flags_offset_in_bytes()  { return offset_of(Klass, _access_flags); }
   // Unpacking layout_helper:
   enum {
     _lh_neutral_value           = 0,  // neutral non-array non-instance value
     _lh_instance_slow_path_bit  = 0x01,
     _lh_log2_element_size_shift = BitsPerByte*0,
     _lh_log2_element_size_mask  = BitsPerLong-1,
     _lh_element_type_shift      = BitsPerByte*1,
     _lh_element_type_mask       = right_n_bits(BitsPerByte),  // shifted mask
     _lh_header_size_shift       = BitsPerByte*2,
     _lh_header_size_mask        = right_n_bits(BitsPerByte),  // shifted mask
     _lh_array_tag_bits          = 2,
     _lh_array_tag_shift         = BitsPerInt - _lh_array_tag_bits,
     _lh_array_tag_type_value    = ~0x00,  // 0xC0000000 >> 30
     _lh_array_tag_obj_value     = ~0x01   // 0x80000000 >> 30
   };
   static int layout_helper_size_in_bytes(jint lh) {
     assert(lh > (jint)_lh_neutral_value, "must be instance");
     return (int) lh & ~_lh_instance_slow_path_bit;
   }
   static bool layout_helper_needs_slow_path(jint lh) {
     assert(lh > (jint)_lh_neutral_value, "must be instance");
     return (lh & _lh_instance_slow_path_bit) != 0;
   }
   static bool layout_helper_is_instance(jint lh) {
     return (jint)lh > (jint)_lh_neutral_value;
   }
   static bool layout_helper_is_javaArray(jint lh) {
     return (jint)lh < (jint)_lh_neutral_value;
   }
   static bool layout_helper_is_typeArray(jint lh) {
     // _lh_array_tag_type_value == (lh >> _lh_array_tag_shift);
     return (juint)lh >= (juint)(_lh_array_tag_type_value << _lh_array_tag_shift);
   }
   static bool layout_helper_is_objArray(jint lh) {
     // _lh_array_tag_obj_value == (lh >> _lh_array_tag_shift);
     return (jint)lh < (jint)(_lh_array_tag_type_value << _lh_array_tag_shift);
   }
   static int layout_helper_header_size(jint lh) {
     assert(lh < (jint)_lh_neutral_value, "must be array");
     int hsize = (lh >> _lh_header_size_shift) & _lh_header_size_mask;
     assert(hsize > 0 && hsize < (int)sizeof(oopDesc)*3, "sanity");
     return hsize;
   }
   static BasicType layout_helper_element_type(jint lh) {
     assert(lh < (jint)_lh_neutral_value, "must be array");
     int btvalue = (lh >> _lh_element_type_shift) & _lh_element_type_mask;
     assert(btvalue >= T_BOOLEAN && btvalue <= T_OBJECT, "sanity");
     return (BasicType) btvalue;
   }
   static int layout_helper_log2_element_size(jint lh) {
     assert(lh < (jint)_lh_neutral_value, "must be array");
     int l2esz = (lh >> _lh_log2_element_size_shift) & _lh_log2_element_size_mask;
     assert(l2esz <= LogBitsPerLong, "sanity");
     return l2esz;
   }
   static jint array_layout_helper(jint tag, int hsize, BasicType etype, int log2_esize) {
     return (tag        << _lh_array_tag_shift)
       |    (hsize      << _lh_header_size_shift)
       |    ((int)etype << _lh_element_type_shift)
       |    (log2_esize << _lh_log2_element_size_shift);
   }
   static jint instance_layout_helper(jint size, bool slow_path_flag) {
     return (size << LogHeapWordSize)
       |    (slow_path_flag ? _lh_instance_slow_path_bit : 0);
   }
   static int layout_helper_to_size_helper(jint lh) {
     assert(lh > (jint)_lh_neutral_value, "must be instance");
     // Note that the following expression discards _lh_instance_slow_path_bit.
     return lh >> LogHeapWordSize;
   }
   // Out-of-line version computes everything based on the etype:
   static jint array_layout_helper(BasicType etype);
   // What is the maximum number of primary superclasses any klass can have?
 #ifdef PRODUCT
   static juint primary_super_limit()         { return _primary_super_limit; }
 #else
   static juint primary_super_limit() {
     assert(FastSuperclassLimit <= _primary_super_limit, "parameter oob");
     return FastSuperclassLimit;
   }
 #endif
   // vtables
   virtual klassVtable* vtable() const        { return NULL; }
   static int klass_size_in_bytes()           { return offset_of(Klass, _alloc_count) + sizeof(juint); }  // all "visible" fields
   // subclass check
   bool is_subclass_of(klassOop k) const;
   // subtype check: true if is_subclass_of, or if k is interface and receiver implements it
   bool is_subtype_of(klassOop k) const {
     juint    off = k->klass_part()->super_check_offset();
     klassOop sup = *(klassOop*)( (address)as_klassOop() + off );
     const juint secondary_offset = secondary_super_cache_offset_in_bytes() + sizeof(oopDesc);
     if (sup == k) {
       return true;
     } else if (off != secondary_offset) {
       return false;
     } else {
       return search_secondary_supers(k);
     }
   }
   bool search_secondary_supers(klassOop k) const;
   // Find LCA in class hierarchy
   Klass *LCA( Klass *k );
   // Check whether reflection/jni/jvm code is allowed to instantiate this class;
   // if not, throw either an Error or an Exception.
   virtual void check_valid_for_instantiation(bool throwError, TRAPS);
   // Casting
   static Klass* cast(klassOop k) {
     assert(k->is_klass(), "cast to Klass");
     return k->klass_part();
   }
   // array copying
   virtual void  copy_array(arrayOop s, int src_pos, arrayOop d, int dst_pos, int length, TRAPS);
   // tells if the class should be initialized
   virtual bool should_be_initialized() const    { return false; }
   // initializes the klass
   virtual void initialize(TRAPS);
   // lookup operation for MethodLookupCache
   friend class MethodLookupCache;
   virtual methodOop uncached_lookup_method(Symbol* name, Symbol* signature) const;
  public:
   methodOop lookup_method(Symbol* name, Symbol* signature) const {
     return uncached_lookup_method(name, signature);
   }
   // array class with specific rank
   klassOop array_klass(int rank, TRAPS)         {  return array_klass_impl(false, rank, THREAD); }
   // array class with this klass as element type
   klassOop array_klass(TRAPS)                   {  return array_klass_impl(false, THREAD); }
   // These will return NULL instead of allocating on the heap:
   // NB: these can block for a mutex, like other functions with TRAPS arg.
   klassOop array_klass_or_null(int rank);
   klassOop array_klass_or_null();
   virtual oop protection_domain()       { return NULL; }
   virtual oop class_loader()  const     { return NULL; }
  protected:
   virtual klassOop array_klass_impl(bool or_null, int rank, TRAPS);
   virtual klassOop array_klass_impl(bool or_null, TRAPS);
  public:
   virtual void remove_unshareable_info();
   virtual void shared_symbols_iterate(SymbolClosure* closure);
  protected:
   // computes the subtype relationship
   virtual bool compute_is_subtype_of(klassOop k);
  public:
   // subclass accessor (here for convenience; undefined for non-klass objects)
   virtual bool is_leaf_class() const { fatal("not a class"); return false; }
  public:
   // ALL FUNCTIONS BELOW THIS POINT ARE DISPATCHED FROM AN OOP
   // These functions describe behavior for the oop not the KLASS.
   // actual oop size of obj in memory
   virtual int oop_size(oop obj) const = 0;
   // actual oop size of this klass in memory
   virtual int klass_oop_size() const = 0;
   // Returns the Java name for a class (Resource allocated)
   // For arrays, this returns the name of the element with a leading '['.
   // For classes, this returns the name with the package separators
   //     turned into '.'s.
   const char* external_name() const;
   // Returns the name for a class (Resource allocated) as the class
   // would appear in a signature.
   // For arrays, this returns the name of the element with a leading '['.
   // For classes, this returns the name with a leading 'L' and a trailing ';'
   //     and the package separators as '/'.
   virtual const char* signature_name() const;
   // garbage collection support
   virtual void oop_follow_contents(oop obj) = 0;
   virtual int  oop_adjust_pointers(oop obj) = 0;
   // Parallel Scavenge and Parallel Old
   PARALLEL_GC_DECLS_PV
  public:
   // type testing operations
   virtual bool oop_is_instance_slow()       const { return false; }
   virtual bool oop_is_instanceMirror()      const { return false; }
   virtual bool oop_is_instanceRef()         const { return false; }
   virtual bool oop_is_array()               const { return false; }
   virtual bool oop_is_objArray_slow()       const { return false; }
   virtual bool oop_is_klass()               const { return false; }
   virtual bool oop_is_thread()              const { return false; }
   virtual bool oop_is_method()              const { return false; }
   virtual bool oop_is_constMethod()         const { return false; }
   virtual bool oop_is_methodData()          const { return false; }
   virtual bool oop_is_constantPool()        const { return false; }
   virtual bool oop_is_constantPoolCache()   const { return false; }
   virtual bool oop_is_typeArray_slow()      const { return false; }
   virtual bool oop_is_arrayKlass()          const { return false; }
   virtual bool oop_is_objArrayKlass()       const { return false; }
   virtual bool oop_is_typeArrayKlass()      const { return false; }
   virtual bool oop_is_compiledICHolder()    const { return false; }
   virtual bool oop_is_instanceKlass()       const { return false; }
   bool oop_is_javaArray_slow() const {
     return oop_is_objArray_slow() || oop_is_typeArray_slow();
   }
   // Fast non-virtual versions, used by oop.inline.hpp and elsewhere:
   #ifndef ASSERT
   #define assert_same_query(xval, xcheck) xval
   #else
  private:
   static bool assert_same_query(bool xval, bool xslow) {
     assert(xval == xslow, "slow and fast queries agree");
     return xval;
   }
  public:
   #endif
   inline  bool oop_is_instance()            const { return assert_same_query(
                                                     layout_helper_is_instance(layout_helper()),
                                                     oop_is_instance_slow()); }
   inline  bool oop_is_javaArray()           const { return assert_same_query(
                                                     layout_helper_is_javaArray(layout_helper()),
                                                     oop_is_javaArray_slow()); }
   inline  bool oop_is_objArray()            const { return assert_same_query(
                                                     layout_helper_is_objArray(layout_helper()),
                                                     oop_is_objArray_slow()); }
   inline  bool oop_is_typeArray()           const { return assert_same_query(
                                                     layout_helper_is_typeArray(layout_helper()),
                                                     oop_is_typeArray_slow()); }
   #undef assert_same_query
   // Unless overridden, oop is parsable if it has a klass pointer.
   // Parsability of an object is object specific.
   virtual bool oop_is_parsable(oop obj) const { return true; }
   // Unless overridden, oop is safe for concurrent GC processing
   // after its allocation is complete.  The exception to
   // this is the case where objects are changed after allocation.
   // Class redefinition is one of the known exceptions. During
   // class redefinition, an allocated class can changed in order
   // order to create a merged class (the combiniation of the
   // old class definition that has to be perserved and the new class
   // definition which is being created.
   virtual bool oop_is_conc_safe(oop obj) const { return true; }
   // Access flags
   AccessFlags access_flags() const         { return _access_flags;  }
   void set_access_flags(AccessFlags flags) { _access_flags = flags; }
   bool is_public() const                { return _access_flags.is_public(); }
   bool is_final() const                 { return _access_flags.is_final(); }
   bool is_interface() const             { return _access_flags.is_interface(); }
   bool is_abstract() const              { return _access_flags.is_abstract(); }
   bool is_super() const                 { return _access_flags.is_super(); }
   bool is_synthetic() const             { return _access_flags.is_synthetic(); }
   void set_is_synthetic()               { _access_flags.set_is_synthetic(); }
   bool has_finalizer() const            { return _access_flags.has_finalizer(); }
   bool has_final_method() const         { return _access_flags.has_final_method(); }
   void set_has_finalizer()              { _access_flags.set_has_finalizer(); }
   void set_has_final_method()           { _access_flags.set_has_final_method(); }
   bool is_cloneable() const             { return _access_flags.is_cloneable(); }
   void set_is_cloneable()               { _access_flags.set_is_cloneable(); }
   bool has_vanilla_constructor() const  { return _access_flags.has_vanilla_constructor(); }
   void set_has_vanilla_constructor()    { _access_flags.set_has_vanilla_constructor(); }
   bool has_miranda_methods () const     { return access_flags().has_miranda_methods(); }
   void set_has_miranda_methods()        { _access_flags.set_has_miranda_methods(); }
   // Biased locking support
   // Note: the prototype header is always set up to be at least the
   // prototype markOop. If biased locking is enabled it may further be
   // biasable and have an epoch.
   markOop prototype_header() const      { return _prototype_header; }
   // NOTE: once instances of this klass are floating around in the
   // system, this header must only be updated at a safepoint.
   // NOTE 2: currently we only ever set the prototype header to the
   // biasable prototype for instanceKlasses. There is no technical
   // reason why it could not be done for arrayKlasses aside from
   // wanting to reduce the initial scope of this optimization. There
   // are potential problems in setting the bias pattern for
   // JVM-internal oops.
   inline void set_prototype_header(markOop header);
   static int prototype_header_offset_in_bytes() { return offset_of(Klass, _prototype_header); }
   int  biased_lock_revocation_count() const { return (int) _biased_lock_revocation_count; }
   // Atomically increments biased_lock_revocation_count and returns updated value
   int atomic_incr_biased_lock_revocation_count();
   void set_biased_lock_revocation_count(int val) { _biased_lock_revocation_count = (jint) val; }
   jlong last_biased_lock_bulk_revocation_time() { return _last_biased_lock_bulk_revocation_time; }
   void  set_last_biased_lock_bulk_revocation_time(jlong cur_time) { _last_biased_lock_bulk_revocation_time = cur_time; }
 #ifdef TRACE_DEFINE_KLASS_METHODS
   TRACE_DEFINE_KLASS_METHODS;
 #endif
   // garbage collection support
   virtual void follow_weak_klass_links(
     BoolObjectClosure* is_alive, OopClosure* keep_alive);
   // Prefetch within oop iterators.  This is a macro because we
   // can't guarantee that the compiler will inline it.  In 64-bit
   // it generally doesn't.  Signature is
   //
   // static void prefetch_beyond(oop* const start,
   //                             oop* const end,
   //                             const intx foffset,
   //                             const Prefetch::style pstyle);
 #define prefetch_beyond(start, end, foffset, pstyle) {   \
     const intx foffset_ = (foffset);                     \
     const Prefetch::style pstyle_ = (pstyle);            \
     assert(foffset_ > 0, "prefetch beyond, not behind"); \
     if (pstyle_ != Prefetch::do_none) {                  \
       oop* ref = (start);                                \
       if (ref < (end)) {                                 \
         switch (pstyle_) {                               \
         case Prefetch::do_read:                          \
           Prefetch::read(*ref, foffset_);                \
           break;                                         \
         case Prefetch::do_write:                         \
           Prefetch::write(*ref, foffset_);               \
           break;                                         \
         default:                                         \
           ShouldNotReachHere();                          \
           break;                                         \
         }                                                \
       }                                                  \
     }                                                    \
   }
   // iterators
   virtual int oop_oop_iterate(oop obj, OopClosure* blk) = 0;
   virtual int oop_oop_iterate_v(oop obj, OopClosure* blk) {
     return oop_oop_iterate(obj, blk);
   }
 #ifndef SERIALGC
   // In case we don't have a specialized backward scanner use forward
   // iteration.
   virtual int oop_oop_iterate_backwards_v(oop obj, OopClosure* blk) {
     return oop_oop_iterate_v(obj, blk);
   }
 #endif // !SERIALGC
   // Iterates "blk" over all the oops in "obj" (of type "this") within "mr".
   // (I don't see why the _m should be required, but without it the Solaris
   // C++ gives warning messages about overridings of the "oop_oop_iterate"
   // defined above "hiding" this virtual function.  (DLD, 6/20/00)) */
   virtual int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) = 0;
   virtual int oop_oop_iterate_v_m(oop obj, OopClosure* blk, MemRegion mr) {
     return oop_oop_iterate_m(obj, blk, mr);
   }
   // Versions of the above iterators specialized to particular subtypes
   // of OopClosure, to avoid closure virtual calls.
 #define Klass_OOP_OOP_ITERATE_DECL(OopClosureType, nv_suffix)                \
   virtual int oop_oop_iterate##nv_suffix(oop obj, OopClosureType* blk) {     \
     /* Default implementation reverts to general version. */                 \
     return oop_oop_iterate(obj, blk);                                        \
   }                                                                          \
                                                                              \
   /* Iterates "blk" over all the oops in "obj" (of type "this") within "mr". \
      (I don't see why the _m should be required, but without it the Solaris  \
      C++ gives warning messages about overridings of the "oop_oop_iterate"   \
      defined above "hiding" this virtual function.  (DLD, 6/20/00)) */       \
   virtual int oop_oop_iterate##nv_suffix##_m(oop obj,                        \
                                              OopClosureType* blk,            \
                                              MemRegion mr) {                 \
     return oop_oop_iterate_m(obj, blk, mr);                                  \
   }
   SPECIALIZED_OOP_OOP_ITERATE_CLOSURES_1(Klass_OOP_OOP_ITERATE_DECL)
   SPECIALIZED_OOP_OOP_ITERATE_CLOSURES_2(Klass_OOP_OOP_ITERATE_DECL)
 #ifndef SERIALGC
 #define Klass_OOP_OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix)      \
   virtual int oop_oop_iterate_backwards##nv_suffix(oop obj,                  \
                                                    OopClosureType* blk) {    \
     /* Default implementation reverts to general version. */                 \
     return oop_oop_iterate_backwards_v(obj, blk);                            \
   }
   SPECIALIZED_OOP_OOP_ITERATE_CLOSURES_1(Klass_OOP_OOP_ITERATE_BACKWARDS_DECL)
   SPECIALIZED_OOP_OOP_ITERATE_CLOSURES_2(Klass_OOP_OOP_ITERATE_BACKWARDS_DECL)
 #endif // !SERIALGC
   virtual void array_klasses_do(void f(klassOop k)) {}
   virtual void with_array_klasses_do(void f(klassOop k));
   // Return self, except for abstract classes with exactly 1
   // implementor.  Then return the 1 concrete implementation.
   Klass *up_cast_abstract();
   // klass name
   Symbol* name() const                   { return _name; }
   void set_name(Symbol* n);
   friend class klassKlass;
  public:
   // jvm support
   virtual jint compute_modifier_flags(TRAPS) const;
   // JVMTI support
   virtual jint jvmti_class_status() const;
   // Printing
   virtual void oop_print_value_on(oop obj, outputStream* st);
   virtual void oop_print_on      (oop obj, outputStream* st);
   // Verification
   virtual const char* internal_name() const = 0;
   virtual void oop_verify_on(oop obj, outputStream* st);
   virtual void oop_verify_old_oop(oop obj, oop* p, bool allow_dirty);
   virtual void oop_verify_old_oop(oop obj, narrowOop* p, bool allow_dirty);
   // tells whether obj is partially constructed (gc during class loading)
   virtual bool oop_partially_loaded(oop obj) const { return false; }
   virtual void oop_set_partially_loaded(oop obj) {};
 #ifndef PRODUCT
   void verify_vtable_index(int index);
 #endif
 };
 inline oop klassOopDesc::java_mirror() const                        { return klass_part()->java_mirror(); }
 #endif // SHARE_VM_OOPS_KLASS_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/oops/klass.hpp@94ec88ca68e2 (annotated)

src/share/vm/oops/klass.hpp