duke@435: /*
jrose@1100:  * 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: // A klassVtable abstracts the variable-length vtable that is embedded in instanceKlass
duke@435: // and arrayKlass.  klassVtable objects are used just as convenient transient accessors to the vtable,
duke@435: // not to actually hold the vtable data.
duke@435: // Note: the klassVtable should not be accessed before the class has been verified
duke@435: // (until that point, the vtable is uninitialized).
duke@435: 
duke@435: // Currently a klassVtable contains a direct reference to the vtable data, and is therefore
duke@435: // not preserved across GCs.
duke@435: 
duke@435: class vtableEntry;
duke@435: 
duke@435: class klassVtable : public ResourceObj {
duke@435:   KlassHandle  _klass;            // my klass
duke@435:   int          _tableOffset;      // offset of start of vtable data within klass
duke@435:   int          _length;           // length of vtable (number of entries)
duke@435: #ifndef PRODUCT
duke@435:   int          _verify_count;     // to make verify faster
duke@435: #endif
duke@435: 
duke@435:   // Ordering important, so greater_than (>) can be used as an merge operator.
duke@435:   enum AccessType {
duke@435:     acc_private         = 0,
duke@435:     acc_package_private = 1,
duke@435:     acc_publicprotected = 2
duke@435:   };
duke@435: 
duke@435:  public:
duke@435:   klassVtable(KlassHandle h_klass, void* base, int length) : _klass(h_klass) {
duke@435:     _tableOffset = (address)base - (address)h_klass(); _length = length;
duke@435:   }
duke@435: 
duke@435:   // accessors
duke@435:   vtableEntry* table() const      { return (vtableEntry*)(address(_klass()) + _tableOffset); }
duke@435:   KlassHandle klass() const       { return _klass;  }
duke@435:   int length() const              { return _length; }
duke@435:   inline methodOop method_at(int i) const;
duke@435:   inline methodOop unchecked_method_at(int i) const;
duke@435:   inline oop*      adr_method_at(int i) const;
duke@435: 
duke@435:   // searching; all methods return -1 if not found
duke@435:   int index_of(methodOop m) const                         { return index_of(m, _length); }
duke@435:   int index_of_miranda(symbolOop name, symbolOop signature);
duke@435: 
duke@435:   void initialize_vtable(bool checkconstraints, TRAPS);   // initialize vtable of a new klass
duke@435: 
duke@435:   // conputes vtable length (in words) and the number of miranda methods
duke@435:   static void compute_vtable_size_and_num_mirandas(int &vtable_length, int &num_miranda_methods,
duke@435:                                                    klassOop super, objArrayOop methods,
duke@435:                                                    AccessFlags class_flags, oop classloader,
duke@435:                                                    symbolOop classname, objArrayOop local_interfaces);
duke@435: 
duke@435:   // RedefineClasses() API support:
duke@435:   // If any entry of this vtable points to any of old_methods,
duke@435:   // replace it with the corresponding new_method.
duke@435:   // trace_name_printed is set to true if the current call has
duke@435:   // printed the klass name so that other routines in the adjust_*
duke@435:   // group don't print the klass name.
duke@435:   void adjust_method_entries(methodOop* old_methods, methodOop* new_methods,
duke@435:                              int methods_length, bool * trace_name_printed);
duke@435: 
duke@435:   // Garbage collection
duke@435:   void oop_follow_contents();
duke@435:   void oop_adjust_pointers();
duke@435: 
duke@435: #ifndef SERIALGC
duke@435:   // Parallel Old
duke@435:   void oop_follow_contents(ParCompactionManager* cm);
duke@435:   void oop_update_pointers(ParCompactionManager* cm);
duke@435:   void oop_update_pointers(ParCompactionManager* cm,
duke@435:                            HeapWord* beg_addr, HeapWord* end_addr);
duke@435: #endif // SERIALGC
duke@435: 
duke@435:   // Iterators
duke@435:   void oop_oop_iterate(OopClosure* blk);
duke@435:   void oop_oop_iterate_m(OopClosure* blk, MemRegion mr);
duke@435: 
duke@435:   // Debugging code
duke@435:   void print()                                              PRODUCT_RETURN;
duke@435:   void verify(outputStream* st, bool force = false);
duke@435:   static void print_statistics()                            PRODUCT_RETURN;
duke@435: 
duke@435: #ifndef PRODUCT
duke@435:   bool check_no_old_entries();
duke@435:   void dump_vtable();
duke@435: #endif
duke@435: 
duke@435:  protected:
duke@435:   friend class vtableEntry;
duke@435:  private:
duke@435:   void copy_vtable_to(vtableEntry* start);
duke@435:   int  initialize_from_super(KlassHandle super);
duke@435:   int  index_of(methodOop m, int len) const; // same as index_of, but search only up to len
duke@435:   void put_method_at(methodOop m, int index);
duke@435:   static bool needs_new_vtable_entry(methodOop m, klassOop super, oop classloader, symbolOop classname, AccessFlags access_flags);
duke@435:   AccessType vtable_accessibility_at(int i);
duke@435: 
duke@435:   bool update_super_vtable(instanceKlass* klass, methodHandle target_method, int super_vtable_len, bool checkconstraints, TRAPS);
duke@435: 
duke@435:   // support for miranda methods
duke@435:   bool is_miranda_entry_at(int i);
duke@435:   void fill_in_mirandas(int& initialized);
duke@435:   static bool is_miranda(methodOop m, objArrayOop class_methods, klassOop super);
duke@435:   static void add_new_mirandas_to_list(GrowableArray<methodOop>* list_of_current_mirandas, objArrayOop current_interface_methods, objArrayOop class_methods, klassOop super);
duke@435:   static void get_mirandas(GrowableArray<methodOop>* mirandas, klassOop super, objArrayOop class_methods, objArrayOop local_interfaces);
duke@435:   static int get_num_mirandas(klassOop super, objArrayOop class_methods, objArrayOop local_interfaces);
duke@435: 
duke@435: 
duke@435:   void verify_against(outputStream* st, klassVtable* vt, int index);
duke@435:   inline instanceKlass* ik() const;
duke@435: };
duke@435: 
duke@435: 
duke@435: // private helper class for klassVtable
duke@435: // description of entry points:
duke@435: //    destination is interpreted:
duke@435: //      from_compiled_code_entry_point -> c2iadapter
duke@435: //      from_interpreter_entry_point   -> interpreter entry point
duke@435: //    destination is compiled:
duke@435: //      from_compiled_code_entry_point -> nmethod entry point
duke@435: //      from_interpreter_entry_point   -> i2cadapter
duke@435: class vtableEntry VALUE_OBJ_CLASS_SPEC {
duke@435:  public:
duke@435:   // size in words
duke@435:   static int size() {
duke@435:     return sizeof(vtableEntry) / sizeof(HeapWord);
duke@435:   }
duke@435:   static int method_offset_in_bytes() { return offset_of(vtableEntry, _method); }
duke@435:   methodOop method() const    { return _method; }
duke@435: 
duke@435:  private:
duke@435:   methodOop _method;
duke@435:   void set(methodOop method)  { assert(method != NULL, "use clear"); _method = method; }
duke@435:   void clear()                { _method = NULL; }
duke@435:   void print()                                        PRODUCT_RETURN;
duke@435:   void verify(klassVtable* vt, outputStream* st);
duke@435: 
duke@435:   friend class klassVtable;
duke@435: };
duke@435: 
duke@435: 
duke@435: inline methodOop klassVtable::method_at(int i) const {
duke@435:   assert(i >= 0 && i < _length, "index out of bounds");
duke@435:   assert(table()[i].method() != NULL, "should not be null");
duke@435:   assert(oop(table()[i].method())->is_method(), "should be method");
duke@435:   return table()[i].method();
duke@435: }
duke@435: 
duke@435: inline methodOop klassVtable::unchecked_method_at(int i) const {
duke@435:   assert(i >= 0 && i < _length, "index out of bounds");
duke@435:   return table()[i].method();
duke@435: }
duke@435: 
duke@435: inline oop* klassVtable::adr_method_at(int i) const {
duke@435:   // Allow one past the last entry to be referenced; useful for loop bounds.
duke@435:   assert(i >= 0 && i <= _length, "index out of bounds");
duke@435:   return (oop*)(address(table() + i) + vtableEntry::method_offset_in_bytes());
duke@435: }
duke@435: 
duke@435: // --------------------------------------------------------------------------------
duke@435: class klassItable;
duke@435: class itableMethodEntry;
duke@435: 
duke@435: class itableOffsetEntry VALUE_OBJ_CLASS_SPEC {
duke@435:  private:
duke@435:   klassOop _interface;
duke@435:   int      _offset;
duke@435:  public:
duke@435:   klassOop interface_klass() const { return _interface; }
duke@435:   int      offset() const          { return _offset; }
duke@435: 
duke@435:   static itableMethodEntry* method_entry(klassOop k, int offset) { return (itableMethodEntry*)(((address)k) + offset); }
duke@435:   itableMethodEntry* first_method_entry(klassOop k)              { return method_entry(k, _offset); }
duke@435: 
duke@435:   void initialize(klassOop interf, int offset) { _interface = interf; _offset = offset; }
duke@435: 
duke@435:   // Static size and offset accessors
duke@435:   static int size()                       { return sizeof(itableOffsetEntry) / HeapWordSize; }    // size in words
duke@435:   static int interface_offset_in_bytes()  { return offset_of(itableOffsetEntry, _interface); }
duke@435:   static int offset_offset_in_bytes()     { return offset_of(itableOffsetEntry, _offset); }
duke@435: 
duke@435:   friend class klassItable;
duke@435: };
duke@435: 
duke@435: 
duke@435: class itableMethodEntry VALUE_OBJ_CLASS_SPEC {
duke@435:  private:
duke@435:   methodOop _method;
duke@435: 
duke@435:  public:
duke@435:   methodOop method() const { return _method; }
duke@435: 
duke@435:   void clear()             { _method = NULL; }
duke@435: 
duke@435:   void initialize(methodOop method);
duke@435: 
duke@435:   // Static size and offset accessors
duke@435:   static int size()                         { return sizeof(itableMethodEntry) / HeapWordSize; }  // size in words
duke@435:   static int method_offset_in_bytes()       { return offset_of(itableMethodEntry, _method); }
duke@435: 
duke@435:   friend class klassItable;
duke@435: };
duke@435: 
duke@435: //
duke@435: // Format of an itable
duke@435: //
duke@435: //    ---- offset table ---
duke@435: //    klassOop of interface 1             \
duke@435: //    offset to vtable from start of oop  / offset table entry
duke@435: //    ...
duke@435: //    klassOop of interface n             \
duke@435: //    offset to vtable from start of oop  / offset table entry
duke@435: //    --- vtable for interface 1 ---
duke@435: //    methodOop                           \
duke@435: //    compiler entry point                / method table entry
duke@435: //    ...
duke@435: //    methodOop                           \
duke@435: //    compiler entry point                / method table entry
duke@435: //    -- vtable for interface 2 ---
duke@435: //    ...
duke@435: //
duke@435: class klassItable : public ResourceObj {
duke@435:  private:
duke@435:   instanceKlassHandle  _klass;             // my klass
duke@435:   int                  _table_offset;      // offset of start of itable data within klass (in words)
duke@435:   int                  _size_offset_table; // size of offset table (in itableOffset entries)
duke@435:   int                  _size_method_table; // size of methodtable (in itableMethodEntry entries)
duke@435: 
duke@435:   void initialize_itable_for_interface(int method_table_offset, KlassHandle interf_h, bool checkconstraints, TRAPS);
duke@435:  public:
duke@435:   klassItable(instanceKlassHandle klass);
duke@435: 
duke@435:   itableOffsetEntry* offset_entry(int i) { assert(0 <= i && i <= _size_offset_table, "index out of bounds");
duke@435:                                            return &((itableOffsetEntry*)vtable_start())[i]; }
duke@435: 
duke@435:   itableMethodEntry* method_entry(int i) { assert(0 <= i && i <= _size_method_table, "index out of bounds");
duke@435:                                            return &((itableMethodEntry*)method_start())[i]; }
duke@435: 
dcubed@451:   int size_offset_table()                { return _size_offset_table; }
duke@435: 
duke@435:   // Initialization
duke@435:   void initialize_itable(bool checkconstraints, TRAPS);
duke@435: 
duke@435:   // Updates
duke@435:   void initialize_with_method(methodOop m);
duke@435: 
duke@435:   // RedefineClasses() API support:
duke@435:   // if any entry of this itable points to any of old_methods,
duke@435:   // replace it with the corresponding new_method.
duke@435:   // trace_name_printed is set to true if the current call has
duke@435:   // printed the klass name so that other routines in the adjust_*
duke@435:   // group don't print the klass name.
duke@435:   void adjust_method_entries(methodOop* old_methods, methodOop* new_methods,
duke@435:                              int methods_length, bool * trace_name_printed);
duke@435: 
duke@435:   // Garbage collection
duke@435:   void oop_follow_contents();
duke@435:   void oop_adjust_pointers();
duke@435: 
duke@435: #ifndef SERIALGC
duke@435:   // Parallel Old
duke@435:   void oop_follow_contents(ParCompactionManager* cm);
duke@435:   void oop_update_pointers(ParCompactionManager* cm);
duke@435:   void oop_update_pointers(ParCompactionManager* cm,
duke@435:                            HeapWord* beg_addr, HeapWord* end_addr);
duke@435: #endif // SERIALGC
duke@435: 
duke@435:   // Iterators
duke@435:   void oop_oop_iterate(OopClosure* blk);
duke@435:   void oop_oop_iterate_m(OopClosure* blk, MemRegion mr);
duke@435: 
duke@435:   // Setup of itable
duke@435:   static int compute_itable_size(objArrayHandle transitive_interfaces);
duke@435:   static void setup_itable_offset_table(instanceKlassHandle klass);
duke@435: 
duke@435:   // Resolving of method to index
duke@435:   static int compute_itable_index(methodOop m);
jrose@1100:   // ...and back again:
jrose@1100:   static methodOop method_for_itable_index(klassOop klass, int itable_index);
duke@435: 
duke@435:   // Debugging/Statistics
duke@435:   static void print_statistics() PRODUCT_RETURN;
duke@435:  private:
duke@435:   intptr_t* vtable_start() const { return ((intptr_t*)_klass()) + _table_offset; }
duke@435:   intptr_t* method_start() const { return vtable_start() + _size_offset_table * itableOffsetEntry::size(); }
duke@435: 
duke@435:   // Helper methods
duke@435:   static int  calc_itable_size(int num_interfaces, int num_methods) { return (num_interfaces * itableOffsetEntry::size()) + (num_methods * itableMethodEntry::size()); }
duke@435: 
duke@435:   // Statistics
duke@435:   NOT_PRODUCT(static int  _total_classes;)   // Total no. of classes with itables
duke@435:   NOT_PRODUCT(static long _total_size;)      // Total no. of bytes used for itables
duke@435: 
duke@435:   static void update_stats(int size) PRODUCT_RETURN NOT_PRODUCT({ _total_classes++; _total_size += size; })
duke@435: };