1 /*
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 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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24 
25 #ifndef SHARE_OOPS_OBJARRAYOOP_HPP
26 #define SHARE_OOPS_OBJARRAYOOP_HPP
27 
28 #include "oops/arrayOop.hpp"
29 #include "utilities/align.hpp"
30 #include <type_traits>
31 
32 class Klass;
33 
34 // An objArrayOop is an array containing oops.
35 // Evaluating "String arg[10]" will create an objArrayOop.
36 
37 class objArrayOopDesc : public arrayOopDesc {
38   friend class ArchiveHeapWriter;
39   friend class ObjArrayKlass;
40   friend class Runtime1;
41   friend class psPromotionManager;
42   friend class CSetMarkWordClosure;
43   friend class Continuation;
44   template <typename T>
45   friend class RawOopWriter;
46 
47   template <class T> T* obj_at_addr(int index) const;
48 
49   template <class T>
50   static ptrdiff_t obj_at_offset(int index) {
51     return base_offset_in_bytes() + sizeof(T) * index;
52   }
53 
54  public:
55   // Returns the offset of the first element.
56   static int base_offset_in_bytes() {
57     return arrayOopDesc::base_offset_in_bytes(T_OBJECT);
58   }
59 
60   inline static objArrayOop cast(oop o);
61 
62   // base is the address following the header.
63   HeapWord* base() const;
64 
65   // Accessing
66   oop obj_at(int index) const;
67   oop obj_at(int index, TRAPS) const;
68 
69   void obj_at_put(int index, oop value);
70   void obj_at_put(int index, oop value, TRAPS);
71 
72   Klass* element_klass();
73 
74 public:
75   // special iterators for index ranges, returns size of object
76   template <typename OopClosureType>
77   void oop_iterate_range(OopClosureType* blk, int start, int end);
78 };
79 
80 // See similar requirement for oopDesc.
81 static_assert(std::is_trivially_default_constructible<objArrayOopDesc>::value, "required");
82 
83 #endif // SHARE_OOPS_OBJARRAYOOP_HPP