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.
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 "classfile/vmSymbols.hpp"
26 #include "memory/resourceArea.hpp"
27 #include "oops/annotations.hpp"
28 #include "oops/constantPool.hpp"
29 #include "oops/fieldStreams.inline.hpp"
30 #include "oops/inlineKlass.inline.hpp"
31 #include "oops/instanceKlass.hpp"
32 #include "oops/klass.inline.hpp"
33 #include "oops/oop.inline.hpp"
34 #include "runtime/fieldDescriptor.inline.hpp"
35 #include "runtime/handles.inline.hpp"
36 #include "runtime/signature.hpp"
37
38 Symbol* fieldDescriptor::generic_signature() const {
39 if (!has_generic_signature()) {
40 return nullptr;
41 }
42 return _cp->symbol_at(_fieldinfo.generic_signature_index());
43 }
44
45 bool fieldDescriptor::is_trusted_final() const {
46 InstanceKlass* ik = field_holder();
47 return is_final() && (is_static() || ik->is_hidden() || ik->is_record() || ik->is_inline_klass()
48 || (ik->is_abstract() && !ik->is_identity_class() && !ik->is_interface()));
49 }
50
51 bool fieldDescriptor::is_mutable_static_final() const {
52 InstanceKlass* ik = field_holder();
53 // write protected fields (JLS 17.5.4)
54 if (is_final() && is_static() && ik == vmClasses::System_klass() &&
55 (offset() == java_lang_System::in_offset() || offset() == java_lang_System::out_offset() || offset() == java_lang_System::err_offset())) {
56 return true;
57 }
58 return false;
59 }
60
61 AnnotationArray* fieldDescriptor::annotations() const {
62 InstanceKlass* ik = field_holder();
63 Array<AnnotationArray*>* md = ik->fields_annotations();
64 if (md == nullptr)
65 return nullptr;
66 return md->at(index());
67 }
68
69 AnnotationArray* fieldDescriptor::type_annotations() const {
70 InstanceKlass* ik = field_holder();
71 Array<AnnotationArray*>* type_annos = ik->fields_type_annotations();
72 if (type_annos == nullptr)
73 return nullptr;
74 return type_annos->at(index());
75 }
76
77 constantTag fieldDescriptor::initial_value_tag() const {
78 return constants()->tag_at(initial_value_index());
79 }
80
81 jint fieldDescriptor::int_initial_value() const {
82 return constants()->int_at(initial_value_index());
83 }
84
85 jlong fieldDescriptor::long_initial_value() const {
86 return constants()->long_at(initial_value_index());
87 }
88
89 jfloat fieldDescriptor::float_initial_value() const {
90 return constants()->float_at(initial_value_index());
91 }
92
93 jdouble fieldDescriptor::double_initial_value() const {
94 return constants()->double_at(initial_value_index());
95 }
96
97 oop fieldDescriptor::string_initial_value(TRAPS) const {
98 return constants()->uncached_string_at(initial_value_index(), THREAD);
99 }
100
101 void fieldDescriptor::reinitialize(InstanceKlass* ik, const FieldInfo& fieldinfo) {
102 if (_cp.is_null() || field_holder() != ik) {
103 _cp = constantPoolHandle(Thread::current(), ik->constants());
104 // _cp should now reference ik's constant pool; i.e., ik is now field_holder.
105 // If the class is a scratch class, the constant pool points to the original class,
106 // but that's ok because of constant pool merging.
107 assert(field_holder() == ik || ik->is_scratch_class(), "must be already initialized to this class");
108 }
109 _fieldinfo = fieldinfo;
110 guarantee(_fieldinfo.name_index() != 0 && _fieldinfo.signature_index() != 0, "bad constant pool index for fieldDescriptor");
111 }
112
113 void fieldDescriptor::print_on(outputStream* st, int base_offset) const {
114 access_flags().print_on(st);
115 if (field_flags().is_injected()) st->print("injected ");
116 name()->print_value_on(st);
117 st->print(" ");
118 signature()->print_value_on(st);
119 st->print(" @%d ", offset() + base_offset);
120 if (WizardMode && has_initial_value()) {
121 st->print("(initval ");
122 constantTag t = initial_value_tag();
123 if (t.is_int()) {
124 st->print("int %d)", int_initial_value());
125 } else if (t.is_long()){
126 st->print_jlong(long_initial_value());
127 } else if (t.is_float()){
128 st->print("float %f)", float_initial_value());
129 } else if (t.is_double()){
130 st->print("double %lf)", double_initial_value());
131 }
132 }
133 }
134
135 void fieldDescriptor::print() const { print_on(tty); }
136
137 void fieldDescriptor::print_on_for(outputStream* st, oop obj, int indent, int base_offset) {
138 BasicType ft = field_type();
139 print_on(st, base_offset);
140 st->print(" ");
141 jint as_int = 0;
142 switch (ft) {
143 case T_BYTE:
144 st->print("%d", obj->byte_field(offset()));
145 break;
146 case T_CHAR:
147 {
148 jchar c = obj->char_field(offset());
149 st->print("%c %d", isprint(c) ? c : ' ', c);
150 }
151 break;
152 case T_DOUBLE:
153 st->print("%lf", obj->double_field(offset()));
154 break;
155 case T_FLOAT:
156 st->print("%f", obj->float_field(offset()));
157 break;
158 case T_INT:
159 st->print("%d", obj->int_field(offset()));
160 break;
161 case T_LONG:
162 st->print_jlong(obj->long_field(offset()));
163 break;
164 case T_SHORT:
165 st->print("%d", obj->short_field(offset()));
166 break;
167 case T_BOOLEAN:
168 st->print("%s", obj->bool_field(offset()) ? "true" : "false");
169 break;
170 case T_ARRAY:
171 case T_OBJECT:
172 if (is_flat()) { // only some inline types can be flat
173 InlineKlass* vk = InlineKlass::cast(field_holder()->get_inline_type_field_klass(index()));
174 st->print("Flat inline type field '%s':", vk->name()->as_C_string());
175 if (!is_null_free_inline_type()) {
176 assert(has_null_marker(), "should have null marker");
177 InlineLayoutInfo* li = field_holder()->inline_layout_info_adr(index());
178 int nm_offset = li->null_marker_offset();
179 if (obj->byte_field_acquire(nm_offset) == 0) {
180 st->print(" null");
181 return;
182 }
183 }
184 st->cr();
185 // Print fields of flat field (recursively)
186 int field_offset = offset() - vk->payload_offset();
187 obj = cast_to_oop(cast_from_oop<address>(obj) + field_offset);
188 FieldPrinter print_field(st, obj, indent + 1, base_offset + field_offset );
189 vk->do_nonstatic_fields(&print_field);
190 if (this->field_flags().has_null_marker()) {
191 for (int i = 0; i < indent + 1; i++) st->print(" ");
192 st->print_cr(" - [null_marker] @%d %s",
193 vk->null_marker_offset() - base_offset + field_offset,
194 obj->bool_field(vk->null_marker_offset()) ? "Field marked as non-null" : "Field marked as null");
195 }
196 return; // Do not print underlying representation
197 }
198 // Not flat inline type field, fall through
199 if (obj->obj_field(offset()) != nullptr) {
200 obj->obj_field(offset())->print_value_on(st);
201 } else {
202 st->print("null");
203 }
204 break;
205 default:
206 ShouldNotReachHere();
207 break;
208 }
209
210 // Print a hint as to the underlying integer representation.
211 if (is_reference_type(ft)) {
212 #ifdef _LP64
213 if (UseCompressedOops) {
214 st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));
215 } else {
216 st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset()));
217 }
218 #else
219 st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));
220 #endif
221 } else { // Primitives
222 switch (ft) {
223 case T_LONG: st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset())); break;
224 case T_DOUBLE: st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset())); break;
225 case T_BYTE: st->print(" (" INT8_FORMAT_X_0 ")", obj->byte_field(offset())); break;
226 case T_CHAR: st->print(" (" INT16_FORMAT_X_0 ")", obj->char_field(offset())); break;
227 case T_FLOAT: st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset())); break;
228 case T_INT: st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset())); break;
229 case T_SHORT: st->print(" (" INT16_FORMAT_X_0 ")", obj->short_field(offset())); break;
230 case T_BOOLEAN: st->print(" (" INT8_FORMAT_X_0 ")", obj->bool_field(offset())); break;
231 default:
232 ShouldNotReachHere();
233 break;
234 }
235 }
236 }