8003553: NPG: metaspace objects should be zeroed in constructors
Summary: Zero metadata in constructors, not in allocation (and some in constructors)
Reviewed-by: jmasa, sspitsyn
/*
* Copyright (c) 1997, 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
* 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/klassPS.hpp"
#include "oops/metadata.hpp"
#include "oops/oop.hpp"
#include "runtime/orderAccess.hpp"
#include "trace/traceMacros.hpp"
#include "utilities/accessFlags.hpp"
#include "utilities/macros.hpp"
#if INCLUDE_ALL_GCS
#include "gc_implementation/concurrentMarkSweep/cmsOopClosures.hpp"
#include "gc_implementation/g1/g1OopClosures.hpp"
#include "gc_implementation/parNew/parOopClosures.hpp"
#endif // INCLUDE_ALL_GCS
//
// A Klass 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.
// 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:
// [C++ vtbl ptr ] (contained in Metadata)
// [layout_helper ]
// [super_check_offset ] for fast subtype checks
// [name ]
// [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 ]
// [subklass ] first subclass
// [next_sibling ] link to chain additional subklasses
// [next_link ]
// [class_loader_data]
// [modifier_flags]
// [access_flags ]
// [last_biased_lock_bulk_revocation_time] (64 bits)
// [prototype_header]
// [biased_lock_revocation_count]
// [alloc_count ]
// [_modified_oops]
// [_accumulated_modified_oops]
// [trace_id]
// Forward declarations.
template <class T> class Array;
template <class T> class GrowableArray;
class ClassLoaderData;
class klassVtable;
class ParCompactionManager;
class KlassSizeStats;
class Klass : public Metadata {
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 C++ vtable,
// 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;
// Cache of last observed secondary supertype
Klass* _secondary_super_cache;
// Array of all secondary supertypes
Array<Klass*>* _secondary_supers;
// Ordered list of all primary supertypes
Klass* _primary_supers[_primary_super_limit];
// java/lang/Class instance mirroring this class
oop _java_mirror;
// Superclass
Klass* _super;
// First subclass (NULL if none); _subklass->next_sibling() is next one
Klass* _subklass;
// Sibling link (or NULL); links all subklasses of a klass
Klass* _next_sibling;
// All klasses loaded by a class loader are chained through these links
Klass* _next_link;
// The VM's representation of the ClassLoader used to load this class.
// Provide access the corresponding instance java.lang.ClassLoader.
ClassLoaderData* _class_loader_data;
jint _modifier_flags; // Processed access flags, for use by Class.getModifiers.
AccessFlags _access_flags; // Access flags. The class/interface distinction is stored here.
// 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;
juint _alloc_count; // allocation profiling support
TRACE_DEFINE_KLASS_TRACE_ID;
// Remembered sets support for the oops in the klasses.
jbyte _modified_oops; // Card Table Equivalent (YC/CMS support)
jbyte _accumulated_modified_oops; // Mod Union Equivalent (CMS support)
// Constructor
Klass();
void* operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS);
public:
bool is_klass() const volatile { return true; }
// super
Klass* super() const { return _super; }
void set_super(Klass* k) { _super = k; }
// initializes _super link, _primary_supers & _secondary_supers arrays
void initialize_supers(Klass* k, TRAPS);
void initialize_supers_impl1(Klass* k);
void initialize_supers_impl2(Klass* k);
// klass-specific helper for initializing _secondary_supers
virtual GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots);
// java_super is the Java-level super type as specified by Class.getSuperClass.
virtual Klass* 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; }
Klass* secondary_super_cache() const { return _secondary_super_cache; }
void set_secondary_super_cache(Klass* k) { _secondary_super_cache = k; }
Array<Klass*>* secondary_supers() const { return _secondary_supers; }
void set_secondary_supers(Array<Klass*>* k) { _secondary_supers = k; }
// Return the element of the _super chain of the given depth.
// If there is no such element, return either NULL or this.
Klass* primary_super_of_depth(juint i) const {
assert(i < primary_super_limit(), "oob");
Klass* super = _primary_supers[i];
assert(super == NULL || super->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 = in_bytes(secondary_super_cache_offset());
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() - in_bytes(primary_supers_offset())) / sizeof(Klass*);
assert(d < primary_super_limit(), "oob");
assert(_primary_supers[d] == this, "proper init");
return d;
}
}
// store an oop into a field of a Klass
void klass_oop_store(oop* p, oop v);
void klass_oop_store(volatile oop* p, oop v);
// java mirror
oop java_mirror() const { return _java_mirror; }
void set_java_mirror(oop m) { klass_oop_store(&_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 set_next_link(Klass* k) { _next_link = k; }
Klass* next_link() const { return _next_link; } // The next klass defined by the class loader.
// class loader data
ClassLoaderData* class_loader_data() const { return _class_loader_data; }
void set_class_loader_data(ClassLoaderData* loader_data) { _class_loader_data = loader_data; }
// The Klasses are not placed in the Heap, so the Card Table or
// the Mod Union Table can't be used to mark when klasses have modified oops.
// The CT and MUT bits saves this information for the individual Klasses.
void record_modified_oops() { _modified_oops = 1; }
void clear_modified_oops() { _modified_oops = 0; }
bool has_modified_oops() { return _modified_oops == 1; }
void accumulate_modified_oops() { if (has_modified_oops()) _accumulated_modified_oops = 1; }
void clear_accumulated_modified_oops() { _accumulated_modified_oops = 0; }
bool has_accumulated_modified_oops() { return _accumulated_modified_oops == 1; }
protected: // internal accessors
Klass* subklass_oop() const { return _subklass; }
Klass* next_sibling_oop() const { return _next_sibling; }
void set_subklass(Klass* s);
void set_next_sibling(Klass* s);
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 ByteSize super_offset() { return in_ByteSize(offset_of(Klass, _super)); }
static ByteSize super_check_offset_offset() { return in_ByteSize(offset_of(Klass, _super_check_offset)); }
static ByteSize primary_supers_offset() { return in_ByteSize(offset_of(Klass, _primary_supers)); }
static ByteSize secondary_super_cache_offset() { return in_ByteSize(offset_of(Klass, _secondary_super_cache)); }
static ByteSize secondary_supers_offset() { return in_ByteSize(offset_of(Klass, _secondary_supers)); }
static ByteSize java_mirror_offset() { return in_ByteSize(offset_of(Klass, _java_mirror)); }
static ByteSize modifier_flags_offset() { return in_ByteSize(offset_of(Klass, _modifier_flags)); }
static ByteSize layout_helper_offset() { return in_ByteSize(offset_of(Klass, _layout_helper)); }
static ByteSize access_flags_offset() { return in_ByteSize(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_array(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; }
// subclass check
bool is_subclass_of(Klass* k) const;
// subtype check: true if is_subclass_of, or if k is interface and receiver implements it
bool is_subtype_of(Klass* k) const {
juint off = k->super_check_offset();
Klass* sup = *(Klass**)( (address)this + off );
const juint secondary_offset = in_bytes(secondary_super_cache_offset());
if (sup == k) {
return true;
} else if (off != secondary_offset) {
return false;
} else {
return search_secondary_supers(k);
}
}
bool search_secondary_supers(Klass* 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);
// 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 Method* uncached_lookup_method(Symbol* name, Symbol* signature) const;
public:
Method* lookup_method(Symbol* name, Symbol* signature) const {
return uncached_lookup_method(name, signature);
}
// array class with specific rank
Klass* array_klass(int rank, TRAPS) { return array_klass_impl(false, rank, THREAD); }
// array class with this klass as element type
Klass* 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.
Klass* array_klass_or_null(int rank);
Klass* array_klass_or_null();
virtual oop protection_domain() { return NULL; }
oop class_loader() const;
virtual oop klass_holder() const { return class_loader(); }
protected:
virtual Klass* array_klass_impl(bool or_null, int rank, TRAPS);
virtual Klass* array_klass_impl(bool or_null, TRAPS);
public:
// CDS support - remove and restore oops from metadata. Oops are not shared.
virtual void remove_unshareable_info();
virtual void restore_unshareable_info(TRAPS);
protected:
// computes the subtype relationship
virtual bool compute_is_subtype_of(Klass* 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;
// Size of klass in word size.
virtual int size() const = 0;
#if INCLUDE_SERVICES
virtual void collect_statistics(KlassSizeStats *sz) const;
#endif
// 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
// type testing operations
protected:
virtual bool oop_is_instance_slow() const { return false; }
virtual bool oop_is_array_slow() const { return false; }
virtual bool oop_is_objArray_slow() const { return false; }
virtual bool oop_is_typeArray_slow() const { return false; }
public:
virtual bool oop_is_instanceMirror() const { return false; }
virtual bool oop_is_instanceRef() const { return false; }
// Fast non-virtual versions
#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_array() const { return assert_same_query(
layout_helper_is_array(layout_helper()),
oop_is_array_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
// 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 ByteSize prototype_header_offset() { return in_ByteSize(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; }
TRACE_DEFINE_KLASS_METHODS;
// garbage collection support
virtual void oops_do(OopClosure* cl);
// Iff the class loader (or mirror for anonymous classes) is alive the
// Klass is considered alive.
// The is_alive closure passed in depends on the Garbage Collector used.
bool is_loader_alive(BoolObjectClosure* is_alive);
static void clean_weak_klass_links(BoolObjectClosure* is_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, ExtendedOopClosure* blk) = 0;
virtual int oop_oop_iterate_v(oop obj, ExtendedOopClosure* blk) {
return oop_oop_iterate(obj, blk);
}
#if INCLUDE_ALL_GCS
// In case we don't have a specialized backward scanner use forward
// iteration.
virtual int oop_oop_iterate_backwards_v(oop obj, ExtendedOopClosure* blk) {
return oop_oop_iterate_v(obj, blk);
}
#endif // INCLUDE_ALL_GCS
// 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, ExtendedOopClosure* blk, MemRegion mr) = 0;
virtual int oop_oop_iterate_v_m(oop obj, ExtendedOopClosure* 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)
#if INCLUDE_ALL_GCS
#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 // INCLUDE_ALL_GCS
virtual void array_klasses_do(void f(Klass* k)) {}
virtual void with_array_klasses_do(void f(Klass* 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);
public:
// jvm support
virtual jint compute_modifier_flags(TRAPS) const;
// JVMTI support
virtual jint jvmti_class_status() const;
// Printing
virtual void print_on(outputStream* st) const;
virtual void oop_print_value_on(oop obj, outputStream* st);
virtual void oop_print_on (oop obj, outputStream* st);
virtual const char* internal_name() const = 0;
// Verification
virtual void verify_on(outputStream* st);
void verify() { verify_on(tty); }
#ifndef PRODUCT
void verify_vtable_index(int index);
#endif
virtual void oop_verify_on(oop obj, outputStream* st);
private:
// barriers used by klass_oop_store
void klass_update_barrier_set(oop v);
void klass_update_barrier_set_pre(void* p, oop v);
};
#endif // SHARE_VM_OOPS_KLASS_HPP