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.
 8  *
 9  * This code is distributed in the hope that it will be useful, but WITHOUT
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   void* value_at_addr(int index, jint lh) const;
42 
43   inline oop obj_at(int index) const;
44   inline oop obj_at(int index, TRAPS) const;
45   inline jboolean null_marker_of_obj_at(int index) const;
46   inline jboolean null_marker_of_obj_at(int index, TRAPS) const;
47   inline void obj_at_put(int index, oop value);
48   inline void obj_at_put(int index, oop value, TRAPS);
49 
50   // Sizing
51   static size_t element_size(int lh, int nof_elements) {
52     size_t sz = (size_t) nof_elements;
53     return sz << Klass::layout_helper_log2_element_size(lh);
54   }
55 
56   static int object_size(int lh, int length) {
57     julong size_in_bytes = arrayOopDesc::base_offset_in_bytes(Klass::layout_helper_element_type(lh));
58     size_in_bytes += element_size(lh, length);
59     julong size_in_words = ((size_in_bytes + (HeapWordSize-1)) >> LogHeapWordSize);
60     assert(size_in_words <= (julong)max_jint, "no overflow");
61     return align_object_size((intptr_t)size_in_words);
62   }
63 
64   int object_size(int lh) const;
65 
66 };
67 
68 // See similar requirement for oopDesc.
69 static_assert(std::is_trivially_default_constructible<flatArrayOopDesc>::value, "required");
70 
71 #endif // SHARE_VM_OOPS_FLATARRAYOOP_HPP