duke@435: /*
xdono@631:  * Copyright 1997-2008 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: // An objArrayOop is an array containing oops.
duke@435: // Evaluating "String arg[10]" will create an objArrayOop.
duke@435: 
duke@435: class objArrayOopDesc : public arrayOopDesc {
coleenp@548:   friend class objArrayKlass;
coleenp@548:   friend class Runtime1;
coleenp@548:   friend class psPromotionManager;
ysr@777:   friend class CSMarkOopClosure;
ysr@777:   friend class G1ParScanPartialArrayClosure;
coleenp@548: 
coleenp@548:   template <class T> T* obj_at_addr(int index) const {
coleenp@548:     assert(is_within_bounds(index), "index out of bounds");
coleenp@548:     return &((T*)base())[index];
coleenp@548:   }
coleenp@548: 
duke@435:  public:
twisti@1330:   // Returns the offset of the first element.
twisti@1330:   static int base_offset_in_bytes() {
twisti@1330:     return arrayOopDesc::base_offset_in_bytes(T_OBJECT);
twisti@1330:   }
twisti@1330: 
coleenp@548:   // base is the address following the header.
coleenp@548:   HeapWord* base() const      { return (HeapWord*) arrayOopDesc::base(T_OBJECT); }
coleenp@548: 
duke@435:   // Accessing
coleenp@548:   oop obj_at(int index) const {
coleenp@548:     // With UseCompressedOops decode the narrow oop in the objArray to an
coleenp@548:     // uncompressed oop.  Otherwise this is simply a "*" operator.
coleenp@548:     if (UseCompressedOops) {
coleenp@548:       return load_decode_heap_oop(obj_at_addr<narrowOop>(index));
coleenp@548:     } else {
coleenp@548:       return load_decode_heap_oop(obj_at_addr<oop>(index));
coleenp@548:     }
coleenp@548:   }
duke@435: 
coleenp@548:   void obj_at_put(int index, oop value) {
coleenp@548:     if (UseCompressedOops) {
coleenp@548:       oop_store(obj_at_addr<narrowOop>(index), value);
coleenp@548:     } else {
coleenp@548:       oop_store(obj_at_addr<oop>(index), value);
coleenp@548:     }
coleenp@548:   }
duke@435:   // Sizing
coleenp@548:   static int header_size()    { return arrayOopDesc::header_size(T_OBJECT); }
coleenp@548:   int object_size()           { return object_size(length()); }
coleenp@548:   int array_size()            { return array_size(length()); }
duke@435: 
coleenp@548:   static int object_size(int length) {
coleenp@548:     // This returns the object size in HeapWords.
coleenp@548:     return align_object_size(header_size() + array_size(length));
duke@435:   }
coleenp@548: 
coleenp@548:   // Give size of objArrayOop in HeapWords minus the header
coleenp@548:   static int array_size(int length) {
coleenp@548:     // Without UseCompressedOops, this is simply:
coleenp@548:     // oop->length() * HeapWordsPerOop;
coleenp@548:     // With narrowOops, HeapWordsPerOop is 1/2 or equal 0 as an integer.
coleenp@548:     // The oop elements are aligned up to wordSize
coleenp@548:     const int HeapWordsPerOop = heapOopSize/HeapWordSize;
coleenp@548:     if (HeapWordsPerOop > 0) {
coleenp@548:       return length * HeapWordsPerOop;
coleenp@548:     } else {
coleenp@548:       const int OopsPerHeapWord = HeapWordSize/heapOopSize;
coleenp@548:       int word_len = align_size_up(length, OopsPerHeapWord)/OopsPerHeapWord;
coleenp@548:       return word_len;
coleenp@548:     }
coleenp@548:   }
coleenp@548: 
coleenp@548:   // special iterators for index ranges, returns size of object
coleenp@548: #define ObjArrayOop_OOP_ITERATE_DECL(OopClosureType, nv_suffix)     \
coleenp@548:   int oop_iterate_range(OopClosureType* blk, int start, int end);
coleenp@548: 
coleenp@548:   ALL_OOP_OOP_ITERATE_CLOSURES_1(ObjArrayOop_OOP_ITERATE_DECL)
ysr@777:   ALL_OOP_OOP_ITERATE_CLOSURES_2(ObjArrayOop_OOP_ITERATE_DECL)
duke@435: };