1 /*
2 * Copyright (c) 1999, 2023, 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 "precompiled.hpp"
26 #include "ci/ciInstanceKlass.hpp"
27 #include "ci/ciObjArrayKlass.hpp"
28 #include "ci/ciSymbol.hpp"
29 #include "ci/ciUtilities.inline.hpp"
30 #include "oops/inlineKlass.inline.hpp"
31 #include "oops/objArrayKlass.hpp"
32 #include "runtime/signature.hpp"
33
34 // ciObjArrayKlass
35 //
36 // This class represents a Klass* in the HotSpot virtual machine
37 // whose Klass part is an ObjArrayKlass.
38
39 // ------------------------------------------------------------------
40 // ciObjArrayKlass::ciObjArrayKlass
41 //
42 // Constructor for loaded object array klasses.
43 ciObjArrayKlass::ciObjArrayKlass(Klass* k) : ciArrayKlass(k) {
44 assert(get_Klass()->is_objArray_klass(), "wrong type");
45 Klass* element_Klass = get_ObjArrayKlass()->bottom_klass();
46 _base_element_klass = CURRENT_ENV->get_klass(element_Klass);
47 assert(_base_element_klass->is_instance_klass() ||
48 _base_element_klass->is_type_array_klass(), "bad base klass");
49 if (dimension() == 1) {
50 _element_klass = _base_element_klass;
51 } else {
52 _element_klass = nullptr;
53 }
54 if (!ciObjectFactory::is_initialized()) {
55 assert(_element_klass->is_java_lang_Object(), "only arrays of object are shared");
56 }
57 }
58
59 // ------------------------------------------------------------------
60 // ciObjArrayKlass::ciObjArrayKlass
61 //
62 // Constructor for unloaded object array klasses.
63 ciObjArrayKlass::ciObjArrayKlass(ciSymbol* array_name,
64 ciKlass* base_element_klass,
65 int dimension)
66 : ciArrayKlass(array_name,
67 dimension, T_OBJECT) {
68 _base_element_klass = base_element_klass;
69 assert(_base_element_klass->is_instance_klass() ||
70 _base_element_klass->is_type_array_klass() ||
71 _base_element_klass->is_flat_array_klass(), "bad base klass");
72 if (dimension == 1) {
73 _element_klass = base_element_klass;
74 } else {
75 _element_klass = nullptr;
76 }
77 }
78
79 // ------------------------------------------------------------------
80 // ciObjArrayKlass::element_klass
81 //
82 // What is the one-level element type of this array?
83 ciKlass* ciObjArrayKlass::element_klass() {
84 if (_element_klass == nullptr) {
85 assert(dimension() > 1, "_element_klass should not be null");
86 // Produce the element klass.
87 if (is_loaded()) {
88 VM_ENTRY_MARK;
89 Klass* element_Klass = get_ObjArrayKlass()->element_klass();
90 _element_klass = CURRENT_THREAD_ENV->get_klass(element_Klass);
91 } else {
92 VM_ENTRY_MARK;
93 // We are an unloaded array klass. Attempt to fetch our
94 // element klass by name.
95 _element_klass = CURRENT_THREAD_ENV->get_klass_by_name_impl(
96 this,
97 constantPoolHandle(),
98 construct_array_name(base_element_klass()->name(),
99 dimension() - 1),
100 false);
101 }
102 }
103 return _element_klass;
104 }
105
106 // ------------------------------------------------------------------
107 // ciObjArrayKlass::construct_array_name
108 //
109 // Build an array name from an element name and a dimension.
110 ciSymbol* ciObjArrayKlass::construct_array_name(ciSymbol* element_name,
111 int dimension) {
112 EXCEPTION_CONTEXT;
113 int element_len = element_name->utf8_length();
114 int buflen = dimension + element_len + 3; // '['+ + 'L'? + (element) + ';'? + '\0'
115 char* name = CURRENT_THREAD_ENV->name_buffer(buflen);
116 int pos = 0;
117 for ( ; pos < dimension; pos++) {
118 name[pos] = JVM_SIGNATURE_ARRAY;
119 }
120 Symbol* base_name_sym = element_name->get_symbol();
121 if (Signature::is_array(base_name_sym) ||
122 Signature::has_envelope(base_name_sym)) {
123 strncpy(&name[pos], (char*)element_name->base(), element_len);
124 name[pos + element_len] = '\0';
125 } else {
126 name[pos++] = JVM_SIGNATURE_CLASS;
127 strncpy(&name[pos], (char*)element_name->base(), element_len);
128 name[pos + element_len] = JVM_SIGNATURE_ENDCLASS;
129 name[pos + element_len + 1] = '\0';
130 }
131 return ciSymbol::make(name);
132 }
133
134 // ------------------------------------------------------------------
135 // ciObjArrayKlass::make_impl
136 //
137 // Implementation of make.
138 ciObjArrayKlass* ciObjArrayKlass::make_impl(ciKlass* element_klass) {
139 if (element_klass->is_loaded()) {
140 EXCEPTION_CONTEXT;
141 // The element klass is loaded
142 Klass* array = element_klass->get_Klass()->array_klass(THREAD);
143 if (HAS_PENDING_EXCEPTION) {
144 CLEAR_PENDING_EXCEPTION;
145 CURRENT_THREAD_ENV->record_out_of_memory_failure();
146 return ciEnv::unloaded_ciobjarrayklass();
147 }
148 return CURRENT_THREAD_ENV->get_obj_array_klass(array);
149 }
150
151 // The array klass was unable to be made or the element klass was 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 if (!is_loaded()) {
179 return nullptr;
180 }
181 ciType* base = base_element_type();
182 if (base->is_instance_klass()) {
183 ciInstanceKlass* ik = base->as_instance_klass();
184 // Even though MyValue is final, [LMyValue is only exact if the array
185 // is null-free due to null-free [LMyValue <: null-able [LMyValue.
186 if (ik->is_inlinetype() && !is_elem_null_free()) {
187 return nullptr;
188 }
189 if (ik->exact_klass() != nullptr) {
190 return this;
191 }
192 } else if (base->is_primitive_type()) {
193 return this;
194 }
195 return nullptr;
196 }
197
198 bool ciObjArrayKlass::is_elem_null_free() const {
199 GUARDED_VM_ENTRY(return get_Klass()->is_null_free_array_klass();)
200 }