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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 7  * published by the Free Software Foundation.
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10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
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24 
25 #ifndef SHARE_VM_OOPS_FLATARRAYOOP_HPP
26 #define SHARE_VM_OOPS_FLATARRAYOOP_HPP
27 
28 #include "oops/arrayOop.hpp"
29 #include "oops/inlineKlass.hpp"
30 #include "oops/klass.hpp"
31 #include "oops/objArrayOop.hpp"
32 #include "runtime/handles.hpp"
33 
34 // A flatArrayOop points to a flat array containing inline types (no indirection).
35 // It may include embedded oops in its elements.
36 
37 class flatArrayOopDesc : public objArrayOopDesc {
38 
39  public:
40   void* base() const;
41   static size_t base_offset_in_bytes();
42   void* value_at_addr(int index, jint lh) const;
43   size_t value_offset(int index, jint lh) const;
44   size_t value_offset_from_base(int index, jint lh) const;
45 
46   inline oop obj_at(int index) const;
47   inline oop obj_at(int index, TRAPS) const;
48   inline jboolean null_marker_of_obj_at(int index) const;
49   inline jboolean null_marker_of_obj_at(int index, TRAPS) const;
50   inline void obj_at_put(int index, oop value);
51   inline void obj_at_put(int index, oop value, TRAPS);
52 
53   // Sizing
54   static size_t element_size(int lh, int nof_elements) {
55     size_t sz = (size_t) nof_elements;
56     return sz << Klass::layout_helper_log2_element_size(lh);
57   }
58 
59   static int object_size(int lh, int length) {
60     julong size_in_bytes = arrayOopDesc::base_offset_in_bytes(Klass::layout_helper_element_type(lh));
61     size_in_bytes += element_size(lh, length);
62     julong size_in_words = ((size_in_bytes + (HeapWordSize-1)) >> LogHeapWordSize);
63     assert(size_in_words <= (julong)max_jint, "no overflow");
64     return align_object_size((intptr_t)size_in_words);
65   }
66 
67   int object_size(int lh) const;
68 
69   // Special iterators for an element index range.
70   template <typename OopClosureType>
71   void oop_iterate_elements_range(OopClosureType* blk, int start, int end);
72 
73 };
74 
75 // See similar requirement for oopDesc.
76 static_assert(std::is_trivially_default_constructible<flatArrayOopDesc>::value, "required");
77 
78 #endif // SHARE_VM_OOPS_FLATARRAYOOP_HPP