1 /*
2 * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
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).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "ci/ciInstanceKlass.hpp"
26 #include "ci/ciObjArrayKlass.hpp"
27 #include "ci/ciSymbol.hpp"
28 #include "ci/ciUtilities.inline.hpp"
29 #include "oops/objArrayKlass.hpp"
30 #include "runtime/signature.hpp"
31
32 // ciObjArrayKlass
33 //
34 // This class represents a Klass* in the HotSpot virtual machine
35 // whose Klass part is an ObjArrayKlass.
36
37 // ------------------------------------------------------------------
38 // ciObjArrayKlass::ciObjArrayKlass
39 //
40 // Constructor for loaded object array klasses.
41 ciObjArrayKlass::ciObjArrayKlass(Klass* k) : ciArrayKlass(k) {
42 assert(get_Klass()->is_objArray_klass(), "wrong type");
43 Klass* element_Klass = get_ObjArrayKlass()->bottom_klass();
44 _base_element_klass = CURRENT_ENV->get_klass(element_Klass);
45 assert(_base_element_klass->is_instance_klass() ||
46 _base_element_klass->is_type_array_klass(), "bad base klass");
47 if (dimension() == 1) {
48 _element_klass = _base_element_klass;
49 } else {
50 _element_klass = nullptr;
51 }
52 if (!ciObjectFactory::is_initialized()) {
53 assert(_element_klass->is_java_lang_Object(), "only arrays of object are shared");
54 }
55 }
56
57 // ------------------------------------------------------------------
58 // ciObjArrayKlass::ciObjArrayKlass
59 //
60 // Constructor for unloaded object array klasses.
61 ciObjArrayKlass::ciObjArrayKlass(ciSymbol* array_name,
62 ciKlass* base_element_klass,
63 int dimension)
64 : ciArrayKlass(array_name,
65 dimension, T_OBJECT) {
66 _base_element_klass = base_element_klass;
67 assert(_base_element_klass->is_instance_klass() ||
68 _base_element_klass->is_type_array_klass(), "bad base klass");
69 if (dimension == 1) {
70 _element_klass = base_element_klass;
71 } else {
72 _element_klass = nullptr;
73 }
74 }
75
76 // ------------------------------------------------------------------
77 // ciObjArrayKlass::element_klass
78 //
79 // What is the one-level element type of this array?
80 ciKlass* ciObjArrayKlass::element_klass() {
81 if (_element_klass == nullptr) {
82 assert(dimension() > 1, "_element_klass should not be null");
83 // Produce the element klass.
84 if (is_loaded()) {
85 VM_ENTRY_MARK;
86 Klass* element_Klass = get_ObjArrayKlass()->element_klass();
87 _element_klass = CURRENT_THREAD_ENV->get_klass(element_Klass);
88 } else {
89 VM_ENTRY_MARK;
90 // We are an unloaded array klass. Attempt to fetch our
91 // element klass by name.
92 _element_klass = CURRENT_THREAD_ENV->get_klass_by_name_impl(
93 this,
94 constantPoolHandle(),
95 construct_array_name(base_element_klass()->name(),
96 dimension() - 1),
97 false);
98 }
99 }
100 return _element_klass;
101 }
102
103 // ------------------------------------------------------------------
104 // ciObjArrayKlass::construct_array_name
105 //
106 // Build an array name from an element name and a dimension.
107 ciSymbol* ciObjArrayKlass::construct_array_name(ciSymbol* element_name,
108 int dimension) {
109 EXCEPTION_CONTEXT;
110 int element_len = element_name->utf8_length();
111 int buflen = dimension + element_len + 3; // '['+ + 'L'? + (element) + ';'? + '\0'
112 char* name = CURRENT_THREAD_ENV->name_buffer(buflen);
113 int pos = 0;
114 for ( ; pos < dimension; pos++) {
115 name[pos] = JVM_SIGNATURE_ARRAY;
116 }
117 Symbol* base_name_sym = element_name->get_symbol();
118
119 if (Signature::is_array(base_name_sym) ||
120 Signature::has_envelope(base_name_sym)) {
121 strncpy(&name[pos], (char*)element_name->base(), element_len);
122 name[pos + element_len] = '\0';
123 } else {
124 name[pos++] = JVM_SIGNATURE_CLASS;
125 strncpy(&name[pos], (char*)element_name->base(), element_len);
126 name[pos + element_len] = JVM_SIGNATURE_ENDCLASS;
127 name[pos + element_len + 1] = '\0';
128 }
129 return ciSymbol::make(name);
130 }
131
132 // ------------------------------------------------------------------
133 // ciObjArrayKlass::make_impl
134 //
135 // Implementation of make.
136 ciObjArrayKlass* ciObjArrayKlass::make_impl(ciKlass* element_klass) {
137
138 if (element_klass->is_loaded()) {
139 EXCEPTION_CONTEXT;
140 // The element klass is loaded
141 Klass* array = element_klass->get_Klass()->array_klass(THREAD);
142 if (HAS_PENDING_EXCEPTION) {
143 CLEAR_PENDING_EXCEPTION;
144 CURRENT_THREAD_ENV->record_out_of_memory_failure();
145 return ciEnv::unloaded_ciobjarrayklass();
146 }
147 return CURRENT_THREAD_ENV->get_obj_array_klass(array);
148 }
149
150 // The array klass was unable to be made or the element klass was
151 // not loaded.
152 ciSymbol* array_name = construct_array_name(element_klass->name(), 1);
153 if (array_name == ciEnv::unloaded_cisymbol()) {
154 return ciEnv::unloaded_ciobjarrayklass();
155 }
156 return
157 CURRENT_ENV->get_unloaded_klass(element_klass, array_name)
158 ->as_obj_array_klass();
159 }
160
161 // ------------------------------------------------------------------
162 // ciObjArrayKlass::make
163 //
164 // Make an array klass corresponding to the specified primitive type.
165 ciObjArrayKlass* ciObjArrayKlass::make(ciKlass* element_klass) {
166 GUARDED_VM_ENTRY(return make_impl(element_klass);)
167 }
168
169 ciObjArrayKlass* ciObjArrayKlass::make(ciKlass* element_klass, int dims) {
170 ciKlass* klass = element_klass;
171 for (int i = 0; i < dims; i++) {
172 klass = ciObjArrayKlass::make(klass);
173 }
174 return klass->as_obj_array_klass();
175 }
176
177 ciKlass* ciObjArrayKlass::exact_klass() {
178 ciType* base = base_element_type();
179 if (base->is_instance_klass()) {
180 ciInstanceKlass* ik = base->as_instance_klass();
181 if (ik->exact_klass() != nullptr) {
182 return this;
183 }
184 } else if (base->is_primitive_type()) {
185 return this;
186 }
187 return nullptr;
188 }