--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/oops/klassVtable.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,316 @@
+/*
+ * Copyright 1997-2006 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.
+ *
+ */
+
+// A klassVtable abstracts the variable-length vtable that is embedded in instanceKlass
+// and arrayKlass.  klassVtable objects are used just as convenient transient accessors to the vtable,
+// not to actually hold the vtable data.
+// Note: the klassVtable should not be accessed before the class has been verified
+// (until that point, the vtable is uninitialized).
+
+// Currently a klassVtable contains a direct reference to the vtable data, and is therefore
+// not preserved across GCs.
+
+class vtableEntry;
+
+class klassVtable : public ResourceObj {
+  KlassHandle  _klass;            // my klass
+  int          _tableOffset;      // offset of start of vtable data within klass
+  int          _length;           // length of vtable (number of entries)
+#ifndef PRODUCT
+  int          _verify_count;     // to make verify faster
+#endif
+
+  // Ordering important, so greater_than (>) can be used as an merge operator.
+  enum AccessType {
+    acc_private         = 0,
+    acc_package_private = 1,
+    acc_publicprotected = 2
+  };
+
+ public:
+  klassVtable(KlassHandle h_klass, void* base, int length) : _klass(h_klass) {
+    _tableOffset = (address)base - (address)h_klass(); _length = length;
+  }
+
+  // accessors
+  vtableEntry* table() const      { return (vtableEntry*)(address(_klass()) + _tableOffset); }
+  KlassHandle klass() const       { return _klass;  }
+  int length() const              { return _length; }
+  inline methodOop method_at(int i) const;
+  inline methodOop unchecked_method_at(int i) const;
+  inline oop*      adr_method_at(int i) const;
+
+  // searching; all methods return -1 if not found
+  int index_of(methodOop m) const                         { return index_of(m, _length); }
+  int index_of_miranda(symbolOop name, symbolOop signature);
+
+  void initialize_vtable(bool checkconstraints, TRAPS);   // initialize vtable of a new klass
+
+  // conputes vtable length (in words) and the number of miranda methods
+  static void compute_vtable_size_and_num_mirandas(int &vtable_length, int &num_miranda_methods,
+                                                   klassOop super, objArrayOop methods,
+                                                   AccessFlags class_flags, oop classloader,
+                                                   symbolOop classname, objArrayOop local_interfaces);
+
+  // RedefineClasses() API support:
+  // If any entry of this vtable points to any of old_methods,
+  // replace it with the corresponding new_method.
+  // trace_name_printed is set to true if the current call has
+  // printed the klass name so that other routines in the adjust_*
+  // group don't print the klass name.
+  void adjust_method_entries(methodOop* old_methods, methodOop* new_methods,
+                             int methods_length, bool * trace_name_printed);
+
+  // Garbage collection
+  void oop_follow_contents();
+  void oop_adjust_pointers();
+
+#ifndef SERIALGC
+  // Parallel Old
+  void oop_follow_contents(ParCompactionManager* cm);
+  void oop_update_pointers(ParCompactionManager* cm);
+  void oop_update_pointers(ParCompactionManager* cm,
+                           HeapWord* beg_addr, HeapWord* end_addr);
+#endif // SERIALGC
+
+  // Iterators
+  void oop_oop_iterate(OopClosure* blk);
+  void oop_oop_iterate_m(OopClosure* blk, MemRegion mr);
+
+  // Debugging code
+  void print()                                              PRODUCT_RETURN;
+  void verify(outputStream* st, bool force = false);
+  static void print_statistics()                            PRODUCT_RETURN;
+
+#ifndef PRODUCT
+  bool check_no_old_entries();
+  void dump_vtable();
+#endif
+
+ protected:
+  friend class vtableEntry;
+ private:
+  void copy_vtable_to(vtableEntry* start);
+  int  initialize_from_super(KlassHandle super);
+  int  index_of(methodOop m, int len) const; // same as index_of, but search only up to len
+  void put_method_at(methodOop m, int index);
+  static bool needs_new_vtable_entry(methodOop m, klassOop super, oop classloader, symbolOop classname, AccessFlags access_flags);
+  AccessType vtable_accessibility_at(int i);
+
+  bool update_super_vtable(instanceKlass* klass, methodHandle target_method, int super_vtable_len, bool checkconstraints, TRAPS);
+
+  // support for miranda methods
+  bool is_miranda_entry_at(int i);
+  void fill_in_mirandas(int& initialized);
+  static bool is_miranda(methodOop m, objArrayOop class_methods, klassOop super);
+  static void add_new_mirandas_to_list(GrowableArray<methodOop>* list_of_current_mirandas, objArrayOop current_interface_methods, objArrayOop class_methods, klassOop super);
+  static void get_mirandas(GrowableArray<methodOop>* mirandas, klassOop super, objArrayOop class_methods, objArrayOop local_interfaces);
+  static int get_num_mirandas(klassOop super, objArrayOop class_methods, objArrayOop local_interfaces);
+
+
+  void verify_against(outputStream* st, klassVtable* vt, int index);
+  inline instanceKlass* ik() const;
+};
+
+
+// private helper class for klassVtable
+// description of entry points:
+//    destination is interpreted:
+//      from_compiled_code_entry_point -> c2iadapter
+//      from_interpreter_entry_point   -> interpreter entry point
+//    destination is compiled:
+//      from_compiled_code_entry_point -> nmethod entry point
+//      from_interpreter_entry_point   -> i2cadapter
+class vtableEntry VALUE_OBJ_CLASS_SPEC {
+ public:
+  // size in words
+  static int size() {
+    return sizeof(vtableEntry) / sizeof(HeapWord);
+  }
+  static int method_offset_in_bytes() { return offset_of(vtableEntry, _method); }
+  methodOop method() const    { return _method; }
+
+ private:
+  methodOop _method;
+  void set(methodOop method)  { assert(method != NULL, "use clear"); _method = method; }
+  void clear()                { _method = NULL; }
+  void print()                                        PRODUCT_RETURN;
+  void verify(klassVtable* vt, outputStream* st);
+
+  friend class klassVtable;
+};
+
+
+inline methodOop klassVtable::method_at(int i) const {
+  assert(i >= 0 && i < _length, "index out of bounds");
+  assert(table()[i].method() != NULL, "should not be null");
+  assert(oop(table()[i].method())->is_method(), "should be method");
+  return table()[i].method();
+}
+
+inline methodOop klassVtable::unchecked_method_at(int i) const {
+  assert(i >= 0 && i < _length, "index out of bounds");
+  return table()[i].method();
+}
+
+inline oop* klassVtable::adr_method_at(int i) const {
+  // Allow one past the last entry to be referenced; useful for loop bounds.
+  assert(i >= 0 && i <= _length, "index out of bounds");
+  return (oop*)(address(table() + i) + vtableEntry::method_offset_in_bytes());
+}
+
+// --------------------------------------------------------------------------------
+class klassItable;
+class itableMethodEntry;
+
+class itableOffsetEntry VALUE_OBJ_CLASS_SPEC {
+ private:
+  klassOop _interface;
+  int      _offset;
+ public:
+  klassOop interface_klass() const { return _interface; }
+  int      offset() const          { return _offset; }
+
+  static itableMethodEntry* method_entry(klassOop k, int offset) { return (itableMethodEntry*)(((address)k) + offset); }
+  itableMethodEntry* first_method_entry(klassOop k)              { return method_entry(k, _offset); }
+
+  void initialize(klassOop interf, int offset) { _interface = interf; _offset = offset; }
+
+  // Static size and offset accessors
+  static int size()                       { return sizeof(itableOffsetEntry) / HeapWordSize; }    // size in words
+  static int interface_offset_in_bytes()  { return offset_of(itableOffsetEntry, _interface); }
+  static int offset_offset_in_bytes()     { return offset_of(itableOffsetEntry, _offset); }
+
+  friend class klassItable;
+};
+
+
+class itableMethodEntry VALUE_OBJ_CLASS_SPEC {
+ private:
+  methodOop _method;
+
+ public:
+  methodOop method() const { return _method; }
+
+  void clear()             { _method = NULL; }
+
+  void initialize(methodOop method);
+
+  // Static size and offset accessors
+  static int size()                         { return sizeof(itableMethodEntry) / HeapWordSize; }  // size in words
+  static int method_offset_in_bytes()       { return offset_of(itableMethodEntry, _method); }
+
+  friend class klassItable;
+};
+
+//
+// Format of an itable
+//
+//    ---- offset table ---
+//    klassOop of interface 1             \
+//    offset to vtable from start of oop  / offset table entry
+//    ...
+//    klassOop of interface n             \
+//    offset to vtable from start of oop  / offset table entry
+//    --- vtable for interface 1 ---
+//    methodOop                           \
+//    compiler entry point                / method table entry
+//    ...
+//    methodOop                           \
+//    compiler entry point                / method table entry
+//    -- vtable for interface 2 ---
+//    ...
+//
+class klassItable : public ResourceObj {
+ private:
+  instanceKlassHandle  _klass;             // my klass
+  int                  _table_offset;      // offset of start of itable data within klass (in words)
+  int                  _size_offset_table; // size of offset table (in itableOffset entries)
+  int                  _size_method_table; // size of methodtable (in itableMethodEntry entries)
+
+  void initialize_itable_for_interface(int method_table_offset, KlassHandle interf_h, bool checkconstraints, TRAPS);
+ public:
+  klassItable(instanceKlassHandle klass);
+
+  itableOffsetEntry* offset_entry(int i) { assert(0 <= i && i <= _size_offset_table, "index out of bounds");
+                                           return &((itableOffsetEntry*)vtable_start())[i]; }
+
+  itableMethodEntry* method_entry(int i) { assert(0 <= i && i <= _size_method_table, "index out of bounds");
+                                           return &((itableMethodEntry*)method_start())[i]; }
+
+  int nof_interfaces()                   { return _size_offset_table; }
+
+  // Initialization
+  void initialize_itable(bool checkconstraints, TRAPS);
+
+  // Updates
+  void initialize_with_method(methodOop m);
+
+  // RedefineClasses() API support:
+  // if any entry of this itable points to any of old_methods,
+  // replace it with the corresponding new_method.
+  // trace_name_printed is set to true if the current call has
+  // printed the klass name so that other routines in the adjust_*
+  // group don't print the klass name.
+  void adjust_method_entries(methodOop* old_methods, methodOop* new_methods,
+                             int methods_length, bool * trace_name_printed);
+
+  // Garbage collection
+  void oop_follow_contents();
+  void oop_adjust_pointers();
+
+#ifndef SERIALGC
+  // Parallel Old
+  void oop_follow_contents(ParCompactionManager* cm);
+  void oop_update_pointers(ParCompactionManager* cm);
+  void oop_update_pointers(ParCompactionManager* cm,
+                           HeapWord* beg_addr, HeapWord* end_addr);
+#endif // SERIALGC
+
+  // Iterators
+  void oop_oop_iterate(OopClosure* blk);
+  void oop_oop_iterate_m(OopClosure* blk, MemRegion mr);
+
+  // Setup of itable
+  static int compute_itable_size(objArrayHandle transitive_interfaces);
+  static void setup_itable_offset_table(instanceKlassHandle klass);
+
+  // Resolving of method to index
+  static int compute_itable_index(methodOop m);
+
+  // Debugging/Statistics
+  static void print_statistics() PRODUCT_RETURN;
+ private:
+  intptr_t* vtable_start() const { return ((intptr_t*)_klass()) + _table_offset; }
+  intptr_t* method_start() const { return vtable_start() + _size_offset_table * itableOffsetEntry::size(); }
+
+  // Helper methods
+  static int  calc_itable_size(int num_interfaces, int num_methods) { return (num_interfaces * itableOffsetEntry::size()) + (num_methods * itableMethodEntry::size()); }
+
+  // Statistics
+  NOT_PRODUCT(static int  _total_classes;)   // Total no. of classes with itables
+  NOT_PRODUCT(static long _total_size;)      // Total no. of bytes used for itables
+
+  static void update_stats(int size) PRODUCT_RETURN NOT_PRODUCT({ _total_classes++; _total_size += size; })
+};