jdk-sandbox: comparison hotspot/src/share/vm/oops/instanceKlass.hpp

equal deleted inserted replaced

-:f3187578ddd3
+:48fd3da4025c
 /*
-* Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
+* Copyright (c) 1997, 2012, 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.
 //    [next sibling               ] Klass
 //    [array klasses              ]
 //    [methods                    ]
 //    [local interfaces           ]
 //    [transitive interfaces      ]
-//    [number of implementors     ]
-//    [implementors               ] klassOop[2]
 //    [fields                     ]
 //    [constants                  ]
 //    [class loader               ]
 //    [protection domain          ]
 //    [signers                    ]
 //    [initializing thread        ]
 //    [Java vtable length         ]
 //    [oop map cache (stack maps) ]
 //    [EMBEDDED Java vtable             ] size in words = vtable_len
 //    [EMBEDDED nonstatic oop-map blocks] size in words = nonstatic_oop_map_size
-//
+//      The embedded nonstatic oop-map blocks are short pairs (offset, length)
-//    The embedded nonstatic oop-map blocks are short pairs (offset, length) indicating
+//      indicating where oops are located in instances of this klass.
-//    where oops are located in instances of this klass.
+//    [EMBEDDED implementor of the interface] only exist for interface
 // forward declaration for class -- see below for definition
 class SuperTypeClosure;
 class JNIid;
 };
 public:
 oop* oop_block_beg() const { return adr_array_klasses(); }
 oop* oop_block_end() const { return adr_methods_default_annotations() + 1; }
-enum {
-implementors_limit = 2              // how many implems can we track?
-};
 protected:
 //
 // The oop block.  See comment in klass.hpp before making changes.
 //
 // the InnerClasses attribute exists, the _inner_classes array length is
 // number_of_inner_classes * 4. If the class has both InnerClasses
 // and EnclosingMethod attributes the _inner_classes array length is
 // number_of_inner_classes * 4 + enclosing_method_attribute_size.
 typeArrayOop    _inner_classes;
-// Implementors of this interface (not valid if it overflows)
-klassOop        _implementors[implementors_limit];
 // Annotations for this class, or null if none.
 typeArrayOop    _class_annotations;
 // Annotation objects (byte arrays) for fields, or null if no annotations.
 // Indices correspond to entries (not indices) in fields array.
 objArrayOop     _fields_annotations;
 jmethodID*      _methods_jmethod_ids;  // jmethodIDs corresponding to method_idnum, or NULL if none
 int*            _methods_cached_itable_indices;  // itable_index cache for JNI invoke corresponding to methods idnum, or NULL
 nmethodBucket*  _dependencies;         // list of dependent nmethods
 nmethod*        _osr_nmethods_head;    // Head of list of on-stack replacement nmethods for this class
 BreakpointInfo* _breakpoints;          // bpt lists, managed by methodOop
-int             _nof_implementors;     // No of implementors of this interface (zero if not an interface)
 // Array of interesting part(s) of the previous version(s) of this
 // instanceKlass. See PreviousVersionWalker below.
 GrowableArray<PreviousVersionNode *>* _previous_versions;
 // JVMTI fields can be moved to their own structure - see 6315920
 unsigned char * _cached_class_file_bytes;       // JVMTI: cached class file, before retransformable agent modified it in CFLH
 // embedded Java vtable follows here
 // embedded Java itables follows here
 // embedded static fields follows here
 // embedded nonstatic oop-map blocks follows here
+// embedded implementor of this interface follows here
+//   The embedded implementor only exists if the current klass is an
+//   iterface. The possible values of the implementor fall into following
+//   three cases:
+//     NULL: no implementor.
+//     A klassOop that's not itself: one implementor.
+//     Itsef: more than one implementors.
 friend class instanceKlassKlass;
 friend class SystemDictionary;
 public:
 static ByteSize init_thread_offset() { return in_ByteSize(sizeof(klassOopDesc) + offset_of(instanceKlass, _init_thread)); }
 // subclass/subinterface checks
 bool implements_interface(klassOop k) const;
-// Access to implementors of an interface. We only store the count
+// Access to the implementor of an interface.
-// of implementors, and in case, there are only a few
+klassOop implementor() const
-// implementors, we store them in a short list.
+{
-// This accessor returns NULL if we walk off the end of the list.
+klassOop* k = start_of_implementor();
-klassOop implementor(int i) const {
+if (k == NULL) {
-return (i < implementors_limit)? _implementors[i]: (klassOop) NULL;
+return NULL;
-}
+} else {
-int  nof_implementors() const       { return _nof_implementors; }
+return *k;
+}
+}
+void set_implementor(klassOop k) {
+assert(is_interface(), "not interface");
+oop* addr = (oop*)start_of_implementor();
+oop_store_without_check(addr, k);
+}
+int  nof_implementors() const       {
+klassOop k = implementor();
+if (k == NULL) {
+return 0;
+} else if (k != this->as_klassOop()) {
+return 1;
+} else {
+return 2;
+}
+}
 void add_implementor(klassOop k);  // k is a new class that implements this interface
 void init_implementor();           // initialize
 // link this class into the implementors list of every interface it implements
 void process_interfaces(Thread *thread);
 return (instanceKlass*) kp;
 }
 // Sizing (in words)
 static int header_size()            { return align_object_offset(oopDesc::header_size() + sizeof(instanceKlass)/HeapWordSize); }
-int object_size() const             { return object_size(align_object_offset(vtable_length()) + align_object_offset(itable_length()) + nonstatic_oop_map_size()); }
+int object_size() const
+{
+return object_size(align_object_offset(vtable_length()) +
+align_object_offset(itable_length()) +
+(is_interface() ?
+(align_object_offset(nonstatic_oop_map_size()) + (int)sizeof(klassOop)/HeapWordSize) :
+nonstatic_oop_map_size()));
+}
 static int vtable_start_offset()    { return header_size(); }
 static int vtable_length_offset()   { return oopDesc::header_size() + offset_of(instanceKlass, _vtable_len) / HeapWordSize; }
 static int object_size(int extra)   { return align_object_size(header_size() + extra); }
 intptr_t* start_of_vtable() const        { return ((intptr_t*)as_klassOop()) + vtable_start_offset(); }
 address static_field_addr(int offset);
 OopMapBlock* start_of_nonstatic_oop_maps() const {
 return (OopMapBlock*)(start_of_itable() + align_object_offset(itable_length()));
 }
+klassOop* start_of_implementor() const {
+if (is_interface()) {
+return (klassOop*)(start_of_nonstatic_oop_maps() +
+nonstatic_oop_map_count());
+} else {
+return NULL;
+}
+};
 // Allocation profiling support
 juint alloc_size() const            { return _alloc_count * size_helper(); }
 void set_alloc_size(juint n)        {}
 oop* adr_class_loader() const      { return (oop*)&this->_class_loader;}
 oop* adr_protection_domain() const { return (oop*)&this->_protection_domain;}
 oop* adr_host_klass() const        { return (oop*)&this->_host_klass;}
 oop* adr_signers() const           { return (oop*)&this->_signers;}
 oop* adr_inner_classes() const     { return (oop*)&this->_inner_classes;}
-oop* adr_implementors() const      { return (oop*)&this->_implementors[0];}
+oop* adr_implementor() const       { return (oop*)start_of_implementor(); }
 oop* adr_methods_jmethod_ids() const             { return (oop*)&this->_methods_jmethod_ids;}
 oop* adr_methods_cached_itable_indices() const   { return (oop*)&this->_methods_cached_itable_indices;}
 oop* adr_class_annotations() const   { return (oop*)&this->_class_annotations;}
 oop* adr_fields_annotations() const  { return (oop*)&this->_fields_annotations;}
 oop* adr_methods_annotations() const { return (oop*)&this->_methods_annotations;}

changeset 12369	48fd3da4025c
parent 12231	6a9cfc59a18a
child 12377	ae6def2813e0