1 /*
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 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 5  * This code is free software; you can redistribute it and/or modify it
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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 
31 #include <type_traits>
32 
33 class Klass;
34 
35 // An objArrayOop is an array containing oops.
36 // Evaluating "String arg[10]" will create an objArrayOop.
37 
38 class objArrayOopDesc : public arrayOopDesc {
39   friend class ArchiveHeapWriter;
40   friend class ObjArrayKlass;
41   friend class Runtime1;
42   friend class psPromotionManager;
43   friend class CSetMarkWordClosure;
44   friend class Continuation;
45   template <typename T>
46   friend class RawOopWriter;
47   friend class AOTMapLogger;
48 
49   template <class T> T* obj_at_addr(int index) const;
50 
51   template <class T>
52   static ptrdiff_t obj_at_offset(int index) {
53     return base_offset_in_bytes() + sizeof(T) * index;
54   }
55 
56  public:
57   // Returns the offset of the first element.
58   static int base_offset_in_bytes() {
59     return arrayOopDesc::base_offset_in_bytes(T_OBJECT);
60   }
61 
62   inline static objArrayOop cast(oop o);
63 
64   // base is the address following the header.
65   HeapWord* base() const;
66 
67   // Accessing
68   oop obj_at(int index) const;
69   oop obj_at(int index, TRAPS) const;
70 
71   void obj_at_put(int index, oop value);
72   void obj_at_put(int index, oop value, TRAPS);
73 
74   Klass* element_klass();
75 
76 public:
77   // special iterators for index ranges, returns size of object
78   template <typename OopClosureType>
79   void oop_iterate_range(OopClosureType* blk, int start, int end);
80 };
81 
82 // See similar requirement for oopDesc.
83 static_assert(std::is_trivially_default_constructible<objArrayOopDesc>::value, "required");
84 
85 #endif // SHARE_OOPS_OBJARRAYOOP_HPP