hotspot/src/share/vm/oops/oop.hpp
changeset 1 489c9b5090e2
child 360 21d113ecbf6a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/oops/oop.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,322 @@
+/*
+ * Copyright 1997-2007 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.
+ *
+ */
+
+// oopDesc is the top baseclass for objects classes.  The {name}Desc classes describe
+// the format of Java objects so the fields can be accessed from C++.
+// oopDesc is abstract.
+// (see oopHierarchy for complete oop class hierarchy)
+//
+// no virtual functions allowed
+
+// store into oop with store check
+void oop_store(oop* p, oop v);
+void oop_store(volatile oop* p, oop v);
+
+// store into oop without store check
+void oop_store_without_check(oop* p, oop v);
+void oop_store_without_check(volatile oop* p, oop v);
+
+
+extern bool always_do_update_barrier;
+
+// Forward declarations.
+class OopClosure;
+class ScanClosure;
+class FastScanClosure;
+class FilteringClosure;
+class BarrierSet;
+class CMSIsAliveClosure;
+
+class PSPromotionManager;
+class ParCompactionManager;
+
+class oopDesc {
+  friend class VMStructs;
+ private:
+  volatile markOop  _mark;
+  klassOop _klass;
+
+  // Fast access to barrier set.  Must be initialized.
+  static BarrierSet* _bs;
+
+ public:
+  markOop  mark() const         { return _mark; }
+  markOop* mark_addr() const    { return (markOop*) &_mark; }
+
+  void set_mark(volatile markOop m)      { _mark = m;   }
+
+  void    release_set_mark(markOop m);
+  markOop cas_set_mark(markOop new_mark, markOop old_mark);
+
+  // Used only to re-initialize the mark word (e.g., of promoted
+  // objects during a GC) -- requires a valid klass pointer
+  void init_mark();
+
+  klassOop klass() const        { return _klass; }
+  oop* klass_addr() const       { return (oop*) &_klass; }
+
+  void set_klass(klassOop k);
+  // For when the klass pointer is being used as a linked list "next" field.
+  void set_klass_to_list_ptr(oop k);
+
+  // size of object header
+  static int header_size()      { return sizeof(oopDesc)/HeapWordSize; }
+  static int header_size_in_bytes() { return sizeof(oopDesc); }
+
+  Klass* blueprint() const;
+
+  // Returns whether this is an instance of k or an instance of a subclass of k
+  bool is_a(klassOop k)  const;
+
+  // Returns the actual oop size of the object
+  int size();
+
+  // Sometimes (for complicated concurrency-related reasons), it is useful
+  // to be able to figure out the size of an object knowing its klass.
+  int size_given_klass(Klass* klass);
+
+  // Some perm gen objects are not parseble immediately after
+  // installation of their klass pointer.
+  bool is_parsable();
+
+  // type test operations (inlined in oop.inline.h)
+  bool is_instance()           const;
+  bool is_instanceRef()        const;
+  bool is_array()              const;
+  bool is_objArray()           const;
+  bool is_symbol()             const;
+  bool is_klass()              const;
+  bool is_thread()             const;
+  bool is_method()             const;
+  bool is_constMethod()        const;
+  bool is_methodData()         const;
+  bool is_constantPool()       const;
+  bool is_constantPoolCache()  const;
+  bool is_typeArray()          const;
+  bool is_javaArray()          const;
+  bool is_compiledICHolder()   const;
+
+ private:
+  // field addresses in oop
+  // byte/char/bool/short fields are always stored as full words
+  void*     field_base(int offset)        const;
+
+  jbyte*    byte_field_addr(int offset)   const;
+  jchar*    char_field_addr(int offset)   const;
+  jboolean* bool_field_addr(int offset)   const;
+  jint*     int_field_addr(int offset)    const;
+  jshort*   short_field_addr(int offset)  const;
+  jlong*    long_field_addr(int offset)   const;
+  jfloat*   float_field_addr(int offset)  const;
+  jdouble*  double_field_addr(int offset) const;
+
+ public:
+  // need this as public for garbage collection
+  oop* obj_field_addr(int offset) const;
+
+  oop obj_field(int offset) const;
+  void obj_field_put(int offset, oop value);
+
+  jbyte byte_field(int offset) const;
+  void byte_field_put(int offset, jbyte contents);
+
+  jchar char_field(int offset) const;
+  void char_field_put(int offset, jchar contents);
+
+  jboolean bool_field(int offset) const;
+  void bool_field_put(int offset, jboolean contents);
+
+  jint int_field(int offset) const;
+  void int_field_put(int offset, jint contents);
+
+  jshort short_field(int offset) const;
+  void short_field_put(int offset, jshort contents);
+
+  jlong long_field(int offset) const;
+  void long_field_put(int offset, jlong contents);
+
+  jfloat float_field(int offset) const;
+  void float_field_put(int offset, jfloat contents);
+
+  jdouble double_field(int offset) const;
+  void double_field_put(int offset, jdouble contents);
+
+  oop obj_field_acquire(int offset) const;
+  void release_obj_field_put(int offset, oop value);
+
+  jbyte byte_field_acquire(int offset) const;
+  void release_byte_field_put(int offset, jbyte contents);
+
+  jchar char_field_acquire(int offset) const;
+  void release_char_field_put(int offset, jchar contents);
+
+  jboolean bool_field_acquire(int offset) const;
+  void release_bool_field_put(int offset, jboolean contents);
+
+  jint int_field_acquire(int offset) const;
+  void release_int_field_put(int offset, jint contents);
+
+  jshort short_field_acquire(int offset) const;
+  void release_short_field_put(int offset, jshort contents);
+
+  jlong long_field_acquire(int offset) const;
+  void release_long_field_put(int offset, jlong contents);
+
+  jfloat float_field_acquire(int offset) const;
+  void release_float_field_put(int offset, jfloat contents);
+
+  jdouble double_field_acquire(int offset) const;
+  void release_double_field_put(int offset, jdouble contents);
+
+  // printing functions for VM debugging
+  void print_on(outputStream* st) const;         // First level print
+  void print_value_on(outputStream* st) const;   // Second level print.
+  void print_address_on(outputStream* st) const; // Address printing
+
+  // printing on default output stream
+  void print();
+  void print_value();
+  void print_address();
+
+  // return the print strings
+  char* print_string();
+  char* print_value_string();
+
+  // verification operations
+  void verify_on(outputStream* st);
+  void verify();
+  void verify_old_oop(oop* p, bool allow_dirty);
+
+  // tells whether this oop is partially constructed (gc during class loading)
+  bool partially_loaded();
+  void set_partially_loaded();
+
+  // locking operations
+  bool is_locked()   const;
+  bool is_unlocked() const;
+  bool has_bias_pattern() const;
+
+  // asserts
+  bool is_oop(bool ignore_mark_word = false) const;
+  bool is_oop_or_null(bool ignore_mark_word = false) const;
+#ifndef PRODUCT
+  bool is_unlocked_oop() const;
+#endif
+
+  // garbage collection
+  bool is_gc_marked() const;
+  // Apply "MarkSweep::mark_and_push" to (the address of) every non-NULL
+  // reference field in "this".
+  void follow_contents();
+  void follow_header();
+
+#ifndef SERIALGC
+  // Parallel Scavenge
+  void copy_contents(PSPromotionManager* pm);
+  void push_contents(PSPromotionManager* pm);
+
+  // Parallel Old
+  void update_contents(ParCompactionManager* cm);
+  void update_contents(ParCompactionManager* cm,
+                       HeapWord* begin_limit,
+                       HeapWord* end_limit);
+  void update_contents(ParCompactionManager* cm,
+                       klassOop old_klass,
+                       HeapWord* begin_limit,
+                       HeapWord* end_limit);
+
+  void follow_contents(ParCompactionManager* cm);
+  void follow_header(ParCompactionManager* cm);
+#endif // SERIALGC
+
+  bool is_perm() const;
+  bool is_perm_or_null() const;
+  bool is_shared() const;
+  bool is_shared_readonly() const;
+  bool is_shared_readwrite() const;
+
+  // Forward pointer operations for scavenge
+  bool is_forwarded() const;
+
+  void forward_to(oop p);
+  bool cas_forward_to(oop p, markOop compare);
+
+#ifndef SERIALGC
+  // Like "forward_to", but inserts the forwarding pointer atomically.
+  // Exactly one thread succeeds in inserting the forwarding pointer, and
+  // this call returns "NULL" for that thread; any other thread has the
+  // value of the forwarding pointer returned and does not modify "this".
+  oop forward_to_atomic(oop p);
+#endif // SERIALGC
+
+  oop forwardee() const;
+
+  // Age of object during scavenge
+  int age() const;
+  void incr_age();
+
+  // Adjust all pointers in this object to point at it's forwarded location and
+  // return the size of this oop.  This is used by the MarkSweep collector.
+  int adjust_pointers();
+  void adjust_header();
+
+#ifndef SERIALGC
+  // Parallel old
+  void update_header();
+  void update_header(HeapWord* beg_addr, HeapWord* end_addr);
+#endif // SERIALGC
+
+  // mark-sweep support
+  void follow_body(int begin, int end);
+
+  // Fast access to barrier set
+  static BarrierSet* bs()            { return _bs; }
+  static void set_bs(BarrierSet* bs) { _bs = bs; }
+
+  // iterators, returns size of object
+#define OOP_ITERATE_DECL(OopClosureType, nv_suffix)                             \
+  int oop_iterate(OopClosureType* blk);                                  \
+  int oop_iterate(OopClosureType* blk, MemRegion mr);  // Only in mr.
+
+  ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DECL)
+  ALL_OOP_OOP_ITERATE_CLOSURES_3(OOP_ITERATE_DECL)
+
+  void oop_iterate_header(OopClosure* blk);
+  void oop_iterate_header(OopClosure* blk, MemRegion mr);
+
+  // identity hash; returns the identity hash key (computes it if necessary)
+  // NOTE with the introduction of UseBiasedLocking that identity_hash() might reach a
+  // safepoint if called on a biased object. Calling code must be aware of that.
+  intptr_t identity_hash();
+  intptr_t slow_identity_hash();
+
+  // marks are forwarded to stack when object is locked
+  bool     has_displaced_mark() const;
+  markOop  displaced_mark() const;
+  void     set_displaced_mark(markOop m);
+
+  // for code generation
+  static int klass_offset_in_bytes()   { return offset_of(oopDesc, _klass); }
+  static int mark_offset_in_bytes()    { return offset_of(oopDesc, _mark); }
+};