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 private:
55 // Give size of objArrayOop in HeapWords minus the header
56 static int array_size(int length) {
57 const uint OopsPerHeapWord = HeapWordSize/heapOopSize;
58 assert(OopsPerHeapWord >= 1 && (HeapWordSize % heapOopSize == 0),
59 "Else the following (new) computation would be in error");
60 uint res = ((uint)length + OopsPerHeapWord - 1)/OopsPerHeapWord;
61 #ifdef ASSERT
62 // The old code is left in for sanity-checking; it'll
63 // go away pretty soon. XXX
64 // Without UseCompressedOops, this is simply:
65 // oop->length() * HeapWordsPerOop;
66 // With narrowOops, HeapWordsPerOop is 1/2 or equal 0 as an integer.
67 // The oop elements are aligned up to wordSize
68 const uint HeapWordsPerOop = heapOopSize/HeapWordSize;
69 uint old_res;
70 if (HeapWordsPerOop > 0) {
71 old_res = length * HeapWordsPerOop;
72 } else {
73 old_res = align_up((uint)length, OopsPerHeapWord)/OopsPerHeapWord;
74 }
75 assert(res == old_res, "Inconsistency between old and new.");
76 #endif // ASSERT
77 return res;
78 }
79
80 public:
81 // Returns the offset of the first element.
82 static int base_offset_in_bytes() {
83 return arrayOopDesc::base_offset_in_bytes(T_OBJECT);
84 }
85
86 // base is the address following the header.
87 HeapWord* base() const;
88
89 // Accessing
90 oop obj_at(int index) const;
91
92 void obj_at_put(int index, oop value);
93
94 oop replace_if_null(int index, oop exchange_value);
95
96 // Sizing
97 static int header_size() { return arrayOopDesc::header_size(T_OBJECT); }
98 size_t object_size() { return object_size(length()); }
99
100 static size_t object_size(int length) {
101 // This returns the object size in HeapWords.
102 uint asz = array_size(length);
103 uint osz = align_object_size(header_size() + asz);
104 assert(osz >= asz, "no overflow");
105 assert((int)osz > 0, "no overflow");
106 return (size_t)osz;
107 }
108
109 Klass* element_klass();
110
111 public:
112 // special iterators for index ranges, returns size of object
113 template <typename OopClosureType>
114 void oop_iterate_range(OopClosureType* blk, int start, int end);
115 };
116
117 // See similar requirement for oopDesc.
118 static_assert(std::is_trivially_default_constructible<objArrayOopDesc>::value, "required");
119
120 #endif // SHARE_OOPS_OBJARRAYOOP_HPP
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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 // base is the address following the header.
61 HeapWord* base() const;
62
63 // Accessing
64 oop obj_at(int index) const;
65
66 void obj_at_put(int index, oop value);
67
68 oop replace_if_null(int index, oop exchange_value);
69
70 // Sizing
71 size_t object_size() { return object_size(length()); }
72
73 static size_t object_size(int length) {
74 // This returns the object size in HeapWords.
75 size_t asz = (size_t)length * heapOopSize;
76 size_t size_words = heap_word_size(base_offset_in_bytes() + asz);
77 size_t osz = align_object_size(size_words);
78 assert(osz < max_jint, "no overflow");
79 return osz;
80 }
81
82 Klass* element_klass();
83
84 public:
85 // special iterators for index ranges, returns size of object
86 template <typename OopClosureType>
87 void oop_iterate_range(OopClosureType* blk, int start, int end);
88 };
89
90 // See similar requirement for oopDesc.
91 static_assert(std::is_trivially_default_constructible<objArrayOopDesc>::value, "required");
92
93 #endif // SHARE_OOPS_OBJARRAYOOP_HPP
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