1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
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 *
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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).
14 *
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23 */
24
25 #ifndef SHARE_OOPS_ARRAYKLASS_HPP
26 #define SHARE_OOPS_ARRAYKLASS_HPP
27
28 #include "oops/klass.hpp"
29
30 class fieldDescriptor;
31 class klassVtable;
32 class ObjArrayKlass;
33
34 // ArrayKlass is the abstract baseclass for all array classes
35
36 class ArrayKlass: public Klass {
37 friend class VMStructs;
38
39 public:
40 enum ArrayProperties : uint32_t {
41 DEFAULT = 0,
42 NULL_RESTRICTED = 1 << 0,
43 NON_ATOMIC = 1 << 1,
44 // FINAL = 1 << 2,
45 // VOLATILE = 1 << 3
46 INVALID = 1 << 4,
47 DUMMY = 1 << 5 // Just to transition the code, to be removed ASAP
48 };
49
50 static bool is_null_restricted(ArrayProperties props) { return (props & NULL_RESTRICTED) != 0; }
51 static bool is_non_atomic(ArrayProperties props) { return (props & NON_ATOMIC) != 0; }
52
53 private:
54 // If you add a new field that points to any metaspace object, you
55 // must add this field to ArrayKlass::metaspace_pointers_do().
56 int _dimension; // This is n'th-dimensional array.
57 ArrayProperties _properties;
58 ObjArrayKlass* volatile _higher_dimension; // Refers the (n+1)'th-dimensional array (if present).
59 ArrayKlass* volatile _lower_dimension; // Refers the (n-1)'th-dimensional array (if present).
60
61 protected:
62 // Constructors
63 // The constructor with the Symbol argument does the real array
64 // initialization, the other is a dummy
65 ArrayKlass(Symbol* name, KlassKind kind, ArrayProperties props, markWord prototype_header = markWord::prototype());
66 ArrayKlass();
67
68 // Create array_name for element klass
69 static Symbol* create_element_klass_array_name(Klass* element_klass, TRAPS);
70
71 void* operator new(size_t size, ClassLoaderData* loader_data, size_t word_size, TRAPS) throw();
72
73 public:
74
75 // Testing operation
76 DEBUG_ONLY(bool is_array_klass_slow() const { return true; })
77
78 // Returns the ObjArrayKlass for n'th dimension.
79 ArrayKlass* array_klass(int n, TRAPS);
80 ArrayKlass* array_klass_or_null(int n);
81
82 // Returns the array class with this class as element type.
83 ArrayKlass* array_klass(TRAPS);
84 ArrayKlass* array_klass_or_null();
85
86 // Instance variables
87 int dimension() const { return _dimension; }
88 void set_dimension(int dimension) { _dimension = dimension; }
89
90 ArrayProperties properties() const { return _properties; }
91 void set_properties(ArrayProperties props) { _properties = props; }
92 static ByteSize properties_offset() { return byte_offset_of(ArrayKlass, _properties); }
93
94 ObjArrayKlass* higher_dimension() const { return _higher_dimension; }
95 inline ObjArrayKlass* higher_dimension_acquire() const; // load with acquire semantics
96 void set_higher_dimension(ObjArrayKlass* k) { _higher_dimension = k; }
97 inline void release_set_higher_dimension(ObjArrayKlass* k); // store with release semantics
98
99 ArrayKlass* lower_dimension() const { return _lower_dimension; }
100 void set_lower_dimension(ArrayKlass* k) { _lower_dimension = k; }
101
102 // offset of first element, including any padding for the sake of alignment
103 int array_header_in_bytes() const { return layout_helper_header_size(layout_helper()); }
104 int log2_element_size() const { return layout_helper_log2_element_size(layout_helper()); }
105 // type of elements (T_OBJECT for both oop arrays and array-arrays)
106 BasicType element_type() const { return layout_helper_element_type(layout_helper()); }
107
108 virtual InstanceKlass* java_super() const;
109
110 // Allocation
111 // Sizes points to the first dimension of the array, subsequent dimensions
112 // are always in higher memory. The callers of these set that up.
113 virtual oop multi_allocate(int rank, jint* sizes, TRAPS);
114
115 // find field according to JVM spec 5.4.3.2, returns the klass in which the field is defined
116 Klass* find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
117
118 // Lookup operations
119 Method* uncached_lookup_method(const Symbol* name,
120 const Symbol* signature,
121 OverpassLookupMode overpass_mode,
122 PrivateLookupMode private_mode = PrivateLookupMode::find) const;
123
124 static ArrayKlass* cast(Klass* k) {
125 return const_cast<ArrayKlass*>(cast(const_cast<const Klass*>(k)));
126 }
127
128 static const ArrayKlass* cast(const Klass* k) {
129 assert(k->is_array_klass(), "cast to ArrayKlass");
130 return static_cast<const ArrayKlass*>(k);
131 }
132
133 GrowableArray<Klass*>* compute_secondary_supers(int num_extra_slots,
134 Array<InstanceKlass*>* transitive_interfaces);
135
136 oop component_mirror() const;
137
138 // Sizing
139 static int static_size(int header_size);
140
141 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
142
143 // Return a handle.
144 static void complete_create_array_klass(ArrayKlass* k, Klass* super_klass, ModuleEntry* module, TRAPS);
145
146 // JVMTI support
147 jint jvmti_class_status() const;
148
149 #if INCLUDE_CDS
150 // CDS support - remove and restore oops from metadata. Oops are not shared.
151 virtual void remove_unshareable_info();
152 virtual void remove_java_mirror();
153 void restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain, TRAPS);
154 void cds_print_value_on(outputStream* st) const;
155 #endif
156
157 void log_array_class_load(Klass* k);
158 // Printing
159 void print_on(outputStream* st) const;
160 void print_value_on(outputStream* st) const;
161
162 void oop_print_on(oop obj, outputStream* st);
163
164 // Verification
165 void verify_on(outputStream* st);
166
167 void oop_verify_on(oop obj, outputStream* st);
168 };
169
170 class ArrayDescription : public StackObj {
171 public:
172 Klass::KlassKind _kind;
173 ArrayKlass::ArrayProperties _properties;
174 LayoutKind _layout_kind;
175 ArrayDescription(Klass::KlassKind k, ArrayKlass::ArrayProperties p, LayoutKind lk) { _kind = k; _properties = p; _layout_kind = lk; }
176 };
177
178 #endif // SHARE_OOPS_ARRAYKLASS_HPP