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/javaClasses.inline.hpp"
26 #include "code/debugInfoRec.hpp"
27 #include "code/pcDesc.hpp"
28 #include "code/scopeDesc.hpp"
29 #include "compiler/compiler_globals.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "oops/oop.inline.hpp"
32 #include "runtime/handles.inline.hpp"
33
34 ScopeDesc::ScopeDesc(const nmethod* code, PcDesc* pd, bool ignore_objects) {
35 int obj_decode_offset = ignore_objects ? DebugInformationRecorder::serialized_null : pd->obj_decode_offset();
36 _code = code;
37 _decode_offset = pd->scope_decode_offset();
38 _objects = decode_object_values(obj_decode_offset);
39 _reexecute = pd->should_reexecute();
40 _rethrow_exception = pd->rethrow_exception();
41 _return_oop = pd->return_oop();
42 _has_ea_local_in_scope = ignore_objects ? false : pd->has_ea_local_in_scope();
43 _arg_escape = ignore_objects ? false : pd->arg_escape();
44 decode_body();
45 }
46
47
48 void ScopeDesc::initialize(const ScopeDesc* parent, int decode_offset) {
49 _code = parent->_code;
50 _decode_offset = decode_offset;
51 _objects = parent->_objects;
52 _reexecute = false; //reexecute only applies to the first scope
53 _rethrow_exception = false;
54 _return_oop = false;
55 _has_ea_local_in_scope = parent->has_ea_local_in_scope();
56 _arg_escape = false;
57 decode_body();
58 }
59
60 ScopeDesc::ScopeDesc(const ScopeDesc* parent) {
61 initialize(parent, parent->_sender_decode_offset);
62 }
63
64 ScopeDesc::ScopeDesc(const ScopeDesc* parent, int decode_offset) {
65 initialize(parent, decode_offset);
66 }
67
68
69 void ScopeDesc::decode_body() {
70 if (decode_offset() == DebugInformationRecorder::serialized_null) {
71 // This is a sentinel record, which is only relevant to
72 // approximate queries. Decode a reasonable frame.
73 _sender_decode_offset = DebugInformationRecorder::serialized_null;
74 _method = _code->method();
75 _bci = InvocationEntryBci;
76 _locals_decode_offset = DebugInformationRecorder::serialized_null;
77 _expressions_decode_offset = DebugInformationRecorder::serialized_null;
78 _monitors_decode_offset = DebugInformationRecorder::serialized_null;
79 } else {
80 // decode header
81 DebugInfoReadStream* stream = stream_at(decode_offset());
82
83 _sender_decode_offset = stream->read_int();
84 _method = stream->read_method();
85 _bci = stream->read_bci();
86
87 // decode offsets for body and sender
88 _locals_decode_offset = stream->read_int();
89 _expressions_decode_offset = stream->read_int();
90 _monitors_decode_offset = stream->read_int();
91 }
92 }
93
94
95 GrowableArray<ScopeValue*>* ScopeDesc::decode_scope_values(int decode_offset) {
96 if (decode_offset == DebugInformationRecorder::serialized_null) return nullptr;
97 DebugInfoReadStream* stream = stream_at(decode_offset);
98 int length = stream->read_int();
99 GrowableArray<ScopeValue*>* result = new GrowableArray<ScopeValue*> (length);
100 for (int index = 0; index < length; index++) {
101 result->push(ScopeValue::read_from(stream));
102 }
103 return result;
104 }
105
106 GrowableArray<ScopeValue*>* ScopeDesc::decode_object_values(int decode_offset) {
107 if (decode_offset == DebugInformationRecorder::serialized_null) return nullptr;
108 GrowableArray<ScopeValue*>* result = new GrowableArray<ScopeValue*>();
109 DebugInfoReadStream* stream = new DebugInfoReadStream(_code, decode_offset, result);
110 int length = stream->read_int();
111 for (int index = 0; index < length; index++) {
112 // Objects values are pushed to 'result' array during read so that
113 // object's fields could reference it (OBJECT_ID_CODE).
114 (void)ScopeValue::read_from(stream);
115 }
116 return result;
117 }
118
119
120 GrowableArray<MonitorValue*>* ScopeDesc::decode_monitor_values(int decode_offset) {
121 if (decode_offset == DebugInformationRecorder::serialized_null) return nullptr;
122 DebugInfoReadStream* stream = stream_at(decode_offset);
123 int length = stream->read_int();
124 GrowableArray<MonitorValue*>* result = new GrowableArray<MonitorValue*> (length);
125 for (int index = 0; index < length; index++) {
126 result->push(new MonitorValue(stream));
127 }
128 return result;
129 }
130
131 GrowableArray<ScopeValue*>* ScopeDesc::objects_to_rematerialize(frame& frm, RegisterMap& map) {
132 if (_objects == nullptr) {
133 return nullptr;
134 }
135
136 GrowableArray<ScopeValue*>* result = new GrowableArray<ScopeValue*>();
137 for (int i = 0; i < _objects->length(); i++) {
138 assert(_objects->at(i)->is_object(), "invalid debug information");
139 ObjectValue* sv = _objects->at(i)->as_ObjectValue();
140
141 // If the object is not referenced in current JVM state, then it's only
142 // a candidate in an ObjectMergeValue, we don't need to rematerialize it
143 // unless when/if it's returned by 'select()' below.
144 if (!sv->is_root()) {
145 continue;
146 }
147
148 if (sv->is_object_merge()) {
149 sv = sv->as_ObjectMergeValue()->select(frm, map);
150 // 'select(...)' may return an ObjectValue that actually represents a
151 // non-scalar replaced object participating in a merge.
152 if (!sv->is_scalar_replaced()) {
153 continue;
154 }
155 }
156
157 result->append_if_missing(sv);
158 }
159
160 return result;
161 }
162
163 DebugInfoReadStream* ScopeDesc::stream_at(int decode_offset) const {
164 return new DebugInfoReadStream(_code, decode_offset, _objects);
165 }
166
167 GrowableArray<ScopeValue*>* ScopeDesc::locals() {
168 return decode_scope_values(_locals_decode_offset);
169 }
170
171 GrowableArray<ScopeValue*>* ScopeDesc::expressions() {
172 return decode_scope_values(_expressions_decode_offset);
173 }
174
175 GrowableArray<MonitorValue*>* ScopeDesc::monitors() {
176 return decode_monitor_values(_monitors_decode_offset);
177 }
178
179 GrowableArray<ScopeValue*>* ScopeDesc::objects() {
180 return _objects;
181 }
182
183 bool ScopeDesc::is_top() const {
184 return _sender_decode_offset == DebugInformationRecorder::serialized_null;
185 }
186
187 ScopeDesc* ScopeDesc::sender() const {
188 if (is_top()) return nullptr;
189 return new ScopeDesc(this);
190 }
191
192
193 #ifndef PRODUCT
194
195 void ScopeDesc::print_value_on(outputStream* st) const {
196 st->print(" ");
197 method()->print_short_name(st);
198 int lineno = method()->line_number_from_bci(bci());
199 if (lineno != -1) {
200 st->print("@%d (line %d)", bci(), lineno);
201 } else {
202 st->print("@%d", bci());
203 }
204 if (should_reexecute()) {
205 st->print(" reexecute=true");
206 }
207 st->cr();
208 }
209
210 void ScopeDesc::print_on(outputStream* st) const {
211 print_on(st, nullptr);
212 }
213
214 void ScopeDesc::print_on(outputStream* st, PcDesc* pd) const {
215 // header
216 if (pd != nullptr) {
217 st->print_cr("ScopeDesc(pc=" PTR_FORMAT " offset=%x):", p2i(pd->real_pc(_code)), pd->pc_offset());
218 }
219
220 print_value_on(st);
221 // decode offsets
222 if (WizardMode) {
223 st->print("ScopeDesc[%d]@" PTR_FORMAT " ", _decode_offset, p2i(_code->content_begin()));
224 st->print_cr(" offset: %d", _decode_offset);
225 st->print_cr(" bci: %d", bci());
226 st->print_cr(" reexecute: %s", should_reexecute() ? "true" : "false");
227 st->print_cr(" locals: %d", _locals_decode_offset);
228 st->print_cr(" stack: %d", _expressions_decode_offset);
229 st->print_cr(" monitor: %d", _monitors_decode_offset);
230 st->print_cr(" sender: %d", _sender_decode_offset);
231 }
232 // locals
233 { GrowableArray<ScopeValue*>* l = ((ScopeDesc*) this)->locals();
234 if (l != nullptr) {
235 st->print_cr(" Locals");
236 for (int index = 0; index < l->length(); index++) {
237 st->print(" - l%d: ", index);
238 l->at(index)->print_on(st);
239 st->cr();
240 }
241 }
242 }
243 // expressions
244 { GrowableArray<ScopeValue*>* l = ((ScopeDesc*) this)->expressions();
245 if (l != nullptr) {
246 st->print_cr(" Expression stack");
247 for (int index = 0; index < l->length(); index++) {
248 st->print(" - @%d: ", index);
249 l->at(index)->print_on(st);
250 st->cr();
251 }
252 }
253 }
254 // monitors
255 { GrowableArray<MonitorValue*>* l = ((ScopeDesc*) this)->monitors();
256 if (l != nullptr) {
257 st->print_cr(" Monitor stack");
258 for (int index = 0; index < l->length(); index++) {
259 st->print(" - @%d: ", index);
260 l->at(index)->print_on(st);
261 st->cr();
262 }
263 }
264 }
265
266 #if COMPILER2_OR_JVMCI
267 if (NOT_JVMCI(DoEscapeAnalysis &&) is_top() && _objects != nullptr) {
268 st->print_cr(" Objects");
269 for (int i = 0; i < _objects->length(); i++) {
270 ObjectValue* sv = (ObjectValue*) _objects->at(i);
271 st->print(" - %d: %c ", i, sv->is_root() ? 'R' : ' ');
272 sv->print_on(st);
273 st->print(", ");
274 if (!sv->is_object_merge()) {
275 st->print("%s", java_lang_Class::as_Klass(sv->klass()->as_ConstantOopReadValue()->value()())->external_name());
276 }
277 sv->print_fields_on(st);
278 st->cr();
279 }
280 }
281 #endif // COMPILER2_OR_JVMCI
282 }
283
284 #endif
285
286 void ScopeDesc::verify() {
287 Thread* current_thread = Thread::current();
288 ResourceMark rm(current_thread);
289 HandleMark hm(current_thread);
290 guarantee(method()->is_method(), "type check");
291
292 // check if we have any illegal elements on the expression stack
293 { GrowableArray<ScopeValue*>* l = expressions();
294 if (l != nullptr) {
295 for (int index = 0; index < l->length(); index++) {
296 //guarantee(!l->at(index)->is_illegal(), "expression element cannot be illegal");
297 }
298 }
299 }
300 }