duke@435: /*
xdono@1014:  * Copyright 1997-2009 Sun Microsystems, Inc.  All Rights Reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
duke@435:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435:  * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435:  * have any questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: // oopDesc is the top baseclass for objects classes.  The {name}Desc classes describe
duke@435: // the format of Java objects so the fields can be accessed from C++.
duke@435: // oopDesc is abstract.
duke@435: // (see oopHierarchy for complete oop class hierarchy)
duke@435: //
duke@435: // no virtual functions allowed
duke@435: 
duke@435: // store into oop with store check
coleenp@548: template <class T> void oop_store(T* p, oop v);
coleenp@548: template <class T> void oop_store(volatile T* p, oop v);
duke@435: 
duke@435: // store into oop without store check
coleenp@548: template <class T> void oop_store_without_check(T* p, oop v);
coleenp@548: template <class T> void oop_store_without_check(volatile T* p, oop v);
duke@435: 
duke@435: 
duke@435: extern bool always_do_update_barrier;
duke@435: 
duke@435: // Forward declarations.
duke@435: class OopClosure;
duke@435: class ScanClosure;
duke@435: class FastScanClosure;
duke@435: class FilteringClosure;
duke@435: class BarrierSet;
duke@435: class CMSIsAliveClosure;
duke@435: 
duke@435: class PSPromotionManager;
duke@435: class ParCompactionManager;
duke@435: 
duke@435: class oopDesc {
duke@435:   friend class VMStructs;
duke@435:  private:
duke@435:   volatile markOop  _mark;
coleenp@548:   union _metadata {
coleenp@548:     wideKlassOop    _klass;
coleenp@548:     narrowOop       _compressed_klass;
coleenp@548:   } _metadata;
duke@435: 
duke@435:   // Fast access to barrier set.  Must be initialized.
duke@435:   static BarrierSet* _bs;
duke@435: 
duke@435:  public:
duke@435:   markOop  mark() const         { return _mark; }
duke@435:   markOop* mark_addr() const    { return (markOop*) &_mark; }
duke@435: 
duke@435:   void set_mark(volatile markOop m)      { _mark = m;   }
duke@435: 
duke@435:   void    release_set_mark(markOop m);
duke@435:   markOop cas_set_mark(markOop new_mark, markOop old_mark);
duke@435: 
duke@435:   // Used only to re-initialize the mark word (e.g., of promoted
duke@435:   // objects during a GC) -- requires a valid klass pointer
duke@435:   void init_mark();
duke@435: 
coleenp@548:   klassOop klass() const;
coleenp@602:   klassOop klass_or_null() const volatile;
coleenp@548:   oop* klass_addr();
coleenp@548:   narrowOop* compressed_klass_addr();
duke@435: 
duke@435:   void set_klass(klassOop k);
coleenp@602: 
coleenp@602:   // For klass field compression
coleenp@602:   int klass_gap() const;
coleenp@602:   void set_klass_gap(int z);
duke@435:   // For when the klass pointer is being used as a linked list "next" field.
duke@435:   void set_klass_to_list_ptr(oop k);
duke@435: 
coleenp@548:   // size of object header, aligned to platform wordSize
coleenp@548:   static int header_size()          { return sizeof(oopDesc)/HeapWordSize; }
duke@435: 
duke@435:   Klass* blueprint() const;
duke@435: 
duke@435:   // Returns whether this is an instance of k or an instance of a subclass of k
duke@435:   bool is_a(klassOop k)  const;
duke@435: 
duke@435:   // Returns the actual oop size of the object
duke@435:   int size();
duke@435: 
duke@435:   // Sometimes (for complicated concurrency-related reasons), it is useful
duke@435:   // to be able to figure out the size of an object knowing its klass.
duke@435:   int size_given_klass(Klass* klass);
duke@435: 
duke@435:   // Some perm gen objects are not parseble immediately after
duke@435:   // installation of their klass pointer.
duke@435:   bool is_parsable();
duke@435: 
jmasa@953:   // Some perm gen objects that have been allocated and initialized
jmasa@953:   // can be changed by the VM when not at a safe point (class rededfinition
jmasa@953:   // is an example).  Such objects should not be examined by the
jmasa@953:   // concurrent processing of a garbage collector if is_conc_safe()
jmasa@953:   // returns false.
jmasa@953:   bool is_conc_safe();
jmasa@953: 
duke@435:   // type test operations (inlined in oop.inline.h)
duke@435:   bool is_instance()           const;
duke@435:   bool is_instanceRef()        const;
duke@435:   bool is_array()              const;
duke@435:   bool is_objArray()           const;
duke@435:   bool is_symbol()             const;
duke@435:   bool is_klass()              const;
duke@435:   bool is_thread()             const;
duke@435:   bool is_method()             const;
duke@435:   bool is_constMethod()        const;
duke@435:   bool is_methodData()         const;
duke@435:   bool is_constantPool()       const;
duke@435:   bool is_constantPoolCache()  const;
duke@435:   bool is_typeArray()          const;
duke@435:   bool is_javaArray()          const;
duke@435:   bool is_compiledICHolder()   const;
duke@435: 
duke@435:  private:
duke@435:   // field addresses in oop
duke@435:   void*     field_base(int offset)        const;
duke@435: 
duke@435:   jbyte*    byte_field_addr(int offset)   const;
duke@435:   jchar*    char_field_addr(int offset)   const;
duke@435:   jboolean* bool_field_addr(int offset)   const;
duke@435:   jint*     int_field_addr(int offset)    const;
duke@435:   jshort*   short_field_addr(int offset)  const;
duke@435:   jlong*    long_field_addr(int offset)   const;
duke@435:   jfloat*   float_field_addr(int offset)  const;
duke@435:   jdouble*  double_field_addr(int offset) const;
coleenp@548:   address*  address_field_addr(int offset) const;
duke@435: 
duke@435:  public:
coleenp@548:   // Need this as public for garbage collection.
coleenp@548:   template <class T> T* obj_field_addr(int offset) const;
duke@435: 
coleenp@570:   // Oop encoding heap max
coleenp@570:   static const uint64_t OopEncodingHeapMax =
coleenp@570:               (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
coleenp@570: 
coleenp@548:   static bool is_null(oop obj);
coleenp@548:   static bool is_null(narrowOop obj);
coleenp@548: 
coleenp@548:   // Decode an oop pointer from a narrowOop if compressed.
coleenp@548:   // These are overloaded for oop and narrowOop as are the other functions
coleenp@548:   // below so that they can be called in template functions.
coleenp@548:   static oop decode_heap_oop_not_null(oop v);
coleenp@548:   static oop decode_heap_oop_not_null(narrowOop v);
coleenp@548:   static oop decode_heap_oop(oop v);
coleenp@548:   static oop decode_heap_oop(narrowOop v);
coleenp@548: 
coleenp@548:   // Encode an oop pointer to a narrow oop.  The or_null versions accept
coleenp@548:   // null oop pointer, others do not in order to eliminate the
coleenp@548:   // null checking branches.
coleenp@548:   static narrowOop encode_heap_oop_not_null(oop v);
coleenp@548:   static narrowOop encode_heap_oop(oop v);
coleenp@548: 
coleenp@548:   // Load an oop out of the Java heap
coleenp@548:   static narrowOop load_heap_oop(narrowOop* p);
coleenp@548:   static oop       load_heap_oop(oop* p);
coleenp@548: 
coleenp@548:   // Load an oop out of Java heap and decode it to an uncompressed oop.
coleenp@548:   static oop load_decode_heap_oop_not_null(narrowOop* p);
coleenp@548:   static oop load_decode_heap_oop_not_null(oop* p);
coleenp@548:   static oop load_decode_heap_oop(narrowOop* p);
coleenp@548:   static oop load_decode_heap_oop(oop* p);
coleenp@548: 
coleenp@548:   // Store an oop into the heap.
coleenp@548:   static void store_heap_oop(narrowOop* p, narrowOop v);
coleenp@548:   static void store_heap_oop(oop* p, oop v);
coleenp@548: 
coleenp@548:   // Encode oop if UseCompressedOops and store into the heap.
coleenp@548:   static void encode_store_heap_oop_not_null(narrowOop* p, oop v);
coleenp@548:   static void encode_store_heap_oop_not_null(oop* p, oop v);
coleenp@548:   static void encode_store_heap_oop(narrowOop* p, oop v);
coleenp@548:   static void encode_store_heap_oop(oop* p, oop v);
coleenp@548: 
coleenp@548:   static void release_store_heap_oop(volatile narrowOop* p, narrowOop v);
coleenp@548:   static void release_store_heap_oop(volatile oop* p, oop v);
coleenp@548: 
coleenp@548:   static void release_encode_store_heap_oop_not_null(volatile narrowOop* p, oop v);
coleenp@548:   static void release_encode_store_heap_oop_not_null(volatile oop* p, oop v);
coleenp@548:   static void release_encode_store_heap_oop(volatile narrowOop* p, oop v);
coleenp@548:   static void release_encode_store_heap_oop(volatile oop* p, oop v);
coleenp@548: 
coleenp@548:   static oop atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest);
coleenp@548:   static oop atomic_compare_exchange_oop(oop exchange_value,
coleenp@548:                                          volatile HeapWord *dest,
coleenp@548:                                          oop compare_value);
coleenp@548: 
coleenp@548:   // Access to fields in a instanceOop through these methods.
duke@435:   oop obj_field(int offset) const;
duke@435:   void obj_field_put(int offset, oop value);
coleenp@548:   void obj_field_raw_put(int offset, oop value);
duke@435: 
duke@435:   jbyte byte_field(int offset) const;
duke@435:   void byte_field_put(int offset, jbyte contents);
duke@435: 
duke@435:   jchar char_field(int offset) const;
duke@435:   void char_field_put(int offset, jchar contents);
duke@435: 
duke@435:   jboolean bool_field(int offset) const;
duke@435:   void bool_field_put(int offset, jboolean contents);
duke@435: 
duke@435:   jint int_field(int offset) const;
duke@435:   void int_field_put(int offset, jint contents);
duke@435: 
duke@435:   jshort short_field(int offset) const;
duke@435:   void short_field_put(int offset, jshort contents);
duke@435: 
duke@435:   jlong long_field(int offset) const;
duke@435:   void long_field_put(int offset, jlong contents);
duke@435: 
duke@435:   jfloat float_field(int offset) const;
duke@435:   void float_field_put(int offset, jfloat contents);
duke@435: 
duke@435:   jdouble double_field(int offset) const;
duke@435:   void double_field_put(int offset, jdouble contents);
duke@435: 
coleenp@548:   address address_field(int offset) const;
coleenp@548:   void address_field_put(int offset, address contents);
coleenp@548: 
duke@435:   oop obj_field_acquire(int offset) const;
duke@435:   void release_obj_field_put(int offset, oop value);
duke@435: 
duke@435:   jbyte byte_field_acquire(int offset) const;
duke@435:   void release_byte_field_put(int offset, jbyte contents);
duke@435: 
duke@435:   jchar char_field_acquire(int offset) const;
duke@435:   void release_char_field_put(int offset, jchar contents);
duke@435: 
duke@435:   jboolean bool_field_acquire(int offset) const;
duke@435:   void release_bool_field_put(int offset, jboolean contents);
duke@435: 
duke@435:   jint int_field_acquire(int offset) const;
duke@435:   void release_int_field_put(int offset, jint contents);
duke@435: 
duke@435:   jshort short_field_acquire(int offset) const;
duke@435:   void release_short_field_put(int offset, jshort contents);
duke@435: 
duke@435:   jlong long_field_acquire(int offset) const;
duke@435:   void release_long_field_put(int offset, jlong contents);
duke@435: 
duke@435:   jfloat float_field_acquire(int offset) const;
duke@435:   void release_float_field_put(int offset, jfloat contents);
duke@435: 
duke@435:   jdouble double_field_acquire(int offset) const;
duke@435:   void release_double_field_put(int offset, jdouble contents);
duke@435: 
duke@435:   // printing functions for VM debugging
duke@435:   void print_on(outputStream* st) const;         // First level print
duke@435:   void print_value_on(outputStream* st) const;   // Second level print.
duke@435:   void print_address_on(outputStream* st) const; // Address printing
duke@435: 
duke@435:   // printing on default output stream
duke@435:   void print();
duke@435:   void print_value();
duke@435:   void print_address();
duke@435: 
duke@435:   // return the print strings
duke@435:   char* print_string();
duke@435:   char* print_value_string();
duke@435: 
duke@435:   // verification operations
duke@435:   void verify_on(outputStream* st);
duke@435:   void verify();
duke@435:   void verify_old_oop(oop* p, bool allow_dirty);
coleenp@548:   void verify_old_oop(narrowOop* p, bool allow_dirty);
duke@435: 
duke@435:   // tells whether this oop is partially constructed (gc during class loading)
duke@435:   bool partially_loaded();
duke@435:   void set_partially_loaded();
duke@435: 
duke@435:   // locking operations
duke@435:   bool is_locked()   const;
duke@435:   bool is_unlocked() const;
duke@435:   bool has_bias_pattern() const;
duke@435: 
duke@435:   // asserts
duke@435:   bool is_oop(bool ignore_mark_word = false) const;
duke@435:   bool is_oop_or_null(bool ignore_mark_word = false) const;
duke@435: #ifndef PRODUCT
duke@435:   bool is_unlocked_oop() const;
duke@435: #endif
duke@435: 
duke@435:   // garbage collection
duke@435:   bool is_gc_marked() const;
duke@435:   // Apply "MarkSweep::mark_and_push" to (the address of) every non-NULL
duke@435:   // reference field in "this".
coleenp@548:   void follow_contents(void);
coleenp@548:   void follow_header(void);
duke@435: 
duke@435: #ifndef SERIALGC
duke@435:   // Parallel Scavenge
duke@435:   void copy_contents(PSPromotionManager* pm);
duke@435:   void push_contents(PSPromotionManager* pm);
duke@435: 
duke@435:   // Parallel Old
duke@435:   void update_contents(ParCompactionManager* cm);
duke@435:   void update_contents(ParCompactionManager* cm,
duke@435:                        HeapWord* begin_limit,
duke@435:                        HeapWord* end_limit);
duke@435:   void update_contents(ParCompactionManager* cm,
duke@435:                        klassOop old_klass,
duke@435:                        HeapWord* begin_limit,
duke@435:                        HeapWord* end_limit);
duke@435: 
duke@435:   void follow_contents(ParCompactionManager* cm);
duke@435:   void follow_header(ParCompactionManager* cm);
duke@435: #endif // SERIALGC
duke@435: 
duke@435:   bool is_perm() const;
duke@435:   bool is_perm_or_null() const;
duke@435:   bool is_shared() const;
duke@435:   bool is_shared_readonly() const;
duke@435:   bool is_shared_readwrite() const;
duke@435: 
duke@435:   // Forward pointer operations for scavenge
duke@435:   bool is_forwarded() const;
duke@435: 
duke@435:   void forward_to(oop p);
duke@435:   bool cas_forward_to(oop p, markOop compare);
duke@435: 
duke@435: #ifndef SERIALGC
duke@435:   // Like "forward_to", but inserts the forwarding pointer atomically.
duke@435:   // Exactly one thread succeeds in inserting the forwarding pointer, and
duke@435:   // this call returns "NULL" for that thread; any other thread has the
duke@435:   // value of the forwarding pointer returned and does not modify "this".
duke@435:   oop forward_to_atomic(oop p);
duke@435: #endif // SERIALGC
duke@435: 
duke@435:   oop forwardee() const;
duke@435: 
duke@435:   // Age of object during scavenge
duke@435:   int age() const;
duke@435:   void incr_age();
duke@435: 
duke@435:   // Adjust all pointers in this object to point at it's forwarded location and
duke@435:   // return the size of this oop.  This is used by the MarkSweep collector.
duke@435:   int adjust_pointers();
duke@435:   void adjust_header();
duke@435: 
duke@435: #ifndef SERIALGC
duke@435:   // Parallel old
duke@435:   void update_header();
duke@435:   void update_header(HeapWord* beg_addr, HeapWord* end_addr);
duke@435: #endif // SERIALGC
duke@435: 
duke@435:   // mark-sweep support
duke@435:   void follow_body(int begin, int end);
duke@435: 
duke@435:   // Fast access to barrier set
duke@435:   static BarrierSet* bs()            { return _bs; }
duke@435:   static void set_bs(BarrierSet* bs) { _bs = bs; }
duke@435: 
duke@435:   // iterators, returns size of object
ysr@777: #define OOP_ITERATE_DECL(OopClosureType, nv_suffix)                      \
duke@435:   int oop_iterate(OopClosureType* blk);                                  \
duke@435:   int oop_iterate(OopClosureType* blk, MemRegion mr);  // Only in mr.
duke@435: 
duke@435:   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DECL)
ysr@777:   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DECL)
ysr@777: 
ysr@777: #ifndef SERIALGC
ysr@777: 
ysr@777: #define OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix)            \
ysr@777:   int oop_iterate_backwards(OopClosureType* blk);
ysr@777: 
ysr@777:   ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DECL)
ysr@777:   ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DECL)
ysr@777: #endif
duke@435: 
duke@435:   void oop_iterate_header(OopClosure* blk);
duke@435:   void oop_iterate_header(OopClosure* blk, MemRegion mr);
duke@435: 
duke@435:   // identity hash; returns the identity hash key (computes it if necessary)
duke@435:   // NOTE with the introduction of UseBiasedLocking that identity_hash() might reach a
duke@435:   // safepoint if called on a biased object. Calling code must be aware of that.
duke@435:   intptr_t identity_hash();
duke@435:   intptr_t slow_identity_hash();
duke@435: 
duke@435:   // marks are forwarded to stack when object is locked
duke@435:   bool     has_displaced_mark() const;
duke@435:   markOop  displaced_mark() const;
duke@435:   void     set_displaced_mark(markOop m);
duke@435: 
duke@435:   // for code generation
duke@435:   static int mark_offset_in_bytes()    { return offset_of(oopDesc, _mark); }
coleenp@548:   static int klass_offset_in_bytes()   { return offset_of(oopDesc, _metadata._klass); }
coleenp@548:   static int klass_gap_offset_in_bytes();
duke@435: };