1 /*
2 * Copyright (c) 1997, 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 #ifndef SHARE_CODE_DEBUGINFO_HPP
26 #define SHARE_CODE_DEBUGINFO_HPP
27
28 #include "code/compressedStream.hpp"
29 #include "code/location.hpp"
30 #include "code/nmethod.hpp"
31 #include "code/oopRecorder.hpp"
32 #include "runtime/javaThread.hpp"
33 #include "utilities/growableArray.hpp"
34
35 // Classes used for serializing debugging information.
36 // These abstractions are introducted to provide symmetric
37 // read and write operations.
38
39 // ScopeValue describes the value of a variable/expression in a scope
40 // - LocationValue describes a value in a given location (in frame or register)
41 // - ConstantValue describes a constant
42
43 class ConstantOopReadValue;
44 class ConstantOopWriteValue;
45 class LocationValue;
46 class ObjectValue;
47 class ObjectMergeValue;
48
49 class ScopeValue: public AnyObj {
50 public:
51 // Testers
52 virtual bool is_location() const { return false; }
53 virtual bool is_object() const { return false; }
54 virtual bool is_object_merge() const { return false; }
55 virtual bool is_auto_box() const { return false; }
56 virtual bool is_marker() const { return false; }
57 virtual bool is_constant_int() const { return false; }
58 virtual bool is_constant_double() const { return false; }
59 virtual bool is_constant_long() const { return false; }
60 virtual bool is_constant_oop() const { return false; }
61 virtual bool equals(ScopeValue* other) const { return false; }
62
63 ConstantOopReadValue* as_ConstantOopReadValue() {
64 assert(is_constant_oop(), "must be");
65 return (ConstantOopReadValue*) this;
66 }
67
68 ConstantOopWriteValue* as_ConstantOopWriteValue() {
69 assert(is_constant_oop(), "must be");
70 return (ConstantOopWriteValue*) this;
71 }
72
73 ObjectValue* as_ObjectValue() {
74 assert(is_object(), "must be");
75 return (ObjectValue*)this;
76 }
77
78 ObjectMergeValue* as_ObjectMergeValue() {
79 assert(is_object_merge(), "must be");
80 return (ObjectMergeValue*)this;
81 }
82
83 LocationValue* as_LocationValue() {
84 assert(is_location(), "must be");
85 return (LocationValue*)this;
86 }
87
88 // Serialization of debugging information
89 virtual void write_on(DebugInfoWriteStream* stream) = 0;
90 static ScopeValue* read_from(DebugInfoReadStream* stream);
91 };
92
93
94 // A Location value describes a value in a given location; i.e. the corresponding
95 // logical entity (e.g., a method temporary) lives in this location.
96
97 class LocationValue: public ScopeValue {
98 private:
99 Location _location;
100 public:
101 LocationValue(Location location) { _location = location; }
102 bool is_location() const { return true; }
103 Location location() const { return _location; }
104
105 // Serialization of debugging information
106 LocationValue(DebugInfoReadStream* stream);
107 void write_on(DebugInfoWriteStream* stream);
108
109 // Printing
110 void print_on(outputStream* st) const;
111 };
112
113 // A placeholder value that has no concrete meaning other than helping constructing
114 // other values.
115
116 class MarkerValue: public ScopeValue {
117 public:
118 bool is_marker() const { return true; }
119
120 // Serialization of debugging information
121 void write_on(DebugInfoWriteStream* stream);
122
123 // Printing
124 void print_on(outputStream* st) const;
125 };
126
127 // An ObjectValue describes an object eliminated by escape analysis.
128
129 class ObjectValue: public ScopeValue {
130 protected:
131 int _id;
132 ScopeValue* _klass;
133 GrowableArray<ScopeValue*> _field_values;
134 Handle _value;
135 bool _visited;
136 bool _is_root; // Will be true if this object is referred to
137 // as a local/expression/monitor in the JVMs.
138 // Otherwise false, meaning it's just a candidate
139 // in an object allocation merge.
140 public:
141 ObjectValue(int id, ScopeValue* klass)
142 : _id(id)
143 , _klass(klass)
144 , _field_values()
145 , _value()
146 , _visited(false)
147 , _is_root(true) {
148 assert(klass->is_constant_oop(), "should be constant java mirror oop");
149 }
150
151 ObjectValue(int id)
152 : _id(id)
153 , _klass(nullptr)
154 , _field_values()
155 , _value()
156 , _visited(false)
157 , _is_root(true) {}
158
159 // Accessors
160 bool is_object() const { return true; }
161 int id() const { return _id; }
162 virtual ScopeValue* klass() const { return _klass; }
163 virtual GrowableArray<ScopeValue*>* field_values() { return &_field_values; }
164 virtual ScopeValue* field_at(int i) const { return _field_values.at(i); }
165 virtual int field_size() { return _field_values.length(); }
166 virtual Handle value() const { return _value; }
167 bool is_visited() const { return _visited; }
168 bool is_root() const { return _is_root; }
169
170 void set_id(int id) { _id = id; }
171 virtual void set_value(oop value);
172 void set_visited(bool visited) { _visited = visited; }
173 void set_root(bool root) { _is_root = root; }
174
175 // Serialization of debugging information
176 void read_object(DebugInfoReadStream* stream);
177 void write_on(DebugInfoWriteStream* stream);
178
179 // Printing
180 void print_on(outputStream* st) const;
181 void print_fields_on(outputStream* st) const;
182 };
183
184 // An ObjectMergeValue describes objects that were inputs to a Phi in C2 and at
185 // least one of them was scalar replaced.
186 // '_selector' is an integer value that will be '-1' if during the execution of
187 // the C2 compiled code the path taken was that of the Phi input that was NOT
188 // scalar replaced. In that case '_merge_pointer' is a pointer to an already
189 // allocated object. If '_selector' is not '-1' then it should be the index of
190 // an object in '_possible_objects'. That object is an ObjectValue describing an
191 // object that was scalar replaced.
192
193 class ObjectMergeValue: public ObjectValue {
194 protected:
195 ScopeValue* _selector;
196 ScopeValue* _merge_pointer;
197 GrowableArray<ScopeValue*> _possible_objects;
198
199 // This holds the ObjectValue that should be used in place of this
200 // ObjectMergeValue. I.e., it's the ScopeValue from _possible_objects that was
201 // selected by 'select()' or is a on-the-fly created ScopeValue representing
202 // the _merge_pointer if _selector is -1.
203 //
204 // We need to keep this reference around because there will be entries in
205 // ScopeDesc that reference this ObjectMergeValue directly. After
206 // rematerialization ObjectMergeValue will be just a wrapper for the
207 // Objectvalue pointed by _selected.
208 ObjectValue* _selected;
209 public:
210 ObjectMergeValue(int id, ScopeValue* merge_pointer, ScopeValue* selector)
211 : ObjectValue(id)
212 , _selector(selector)
213 , _merge_pointer(merge_pointer)
214 , _possible_objects()
215 , _selected(nullptr) {}
216
217 ObjectMergeValue(int id)
218 : ObjectValue(id)
219 , _selector(nullptr)
220 , _merge_pointer(nullptr)
221 , _possible_objects()
222 , _selected(nullptr) {}
223
224 bool is_object_merge() const { return true; }
225 ScopeValue* selector() const { return _selector; }
226 ScopeValue* merge_pointer() const { return _merge_pointer; }
227 GrowableArray<ScopeValue*>* possible_objects() { return &_possible_objects; }
228 ObjectValue* select(frame& fr, RegisterMap& reg_map) ;
229
230 ScopeValue* klass() const { ShouldNotReachHere(); return nullptr; }
231 GrowableArray<ScopeValue*>* field_values() { ShouldNotReachHere(); return nullptr; }
232 ScopeValue* field_at(int i) const { ShouldNotReachHere(); return nullptr; }
233 int field_size() { ShouldNotReachHere(); return -1; }
234
235 Handle value() const;
236 void set_value(oop value) { assert(_selected != nullptr, "Should call select() first."); _selected->set_value(value); }
237
238 // Serialization of debugging information
239 void read_object(DebugInfoReadStream* stream);
240 void write_on(DebugInfoWriteStream* stream);
241 };
242
243 class AutoBoxObjectValue : public ObjectValue {
244 bool _cached;
245 public:
246 bool is_auto_box() const { return true; }
247 bool is_cached() const { return _cached; }
248 void set_cached(bool cached) { _cached = cached; }
249 AutoBoxObjectValue(int id, ScopeValue* klass) : ObjectValue(id, klass), _cached(false) { }
250 AutoBoxObjectValue(int id) : ObjectValue(id), _cached(false) { }
251 };
252
253
254 // A ConstantIntValue describes a constant int; i.e., the corresponding logical entity
255 // is either a source constant or its computation has been constant-folded.
256
257 class ConstantIntValue: public ScopeValue {
258 private:
259 jint _value;
260 public:
261 ConstantIntValue(jint value) { _value = value; }
262 jint value() const { return _value; }
263 bool is_constant_int() const { return true; }
264 bool equals(ScopeValue* other) const { return false; }
265
266 // Serialization of debugging information
267 ConstantIntValue(DebugInfoReadStream* stream);
268 void write_on(DebugInfoWriteStream* stream);
269
270 // Printing
271 void print_on(outputStream* st) const;
272 };
273
274 class ConstantLongValue: public ScopeValue {
275 private:
276 jlong _value;
277 public:
278 ConstantLongValue(jlong value) { _value = value; }
279 jlong value() const { return _value; }
280 bool is_constant_long() const { return true; }
281 bool equals(ScopeValue* other) const { return false; }
282
283 // Serialization of debugging information
284 ConstantLongValue(DebugInfoReadStream* stream);
285 void write_on(DebugInfoWriteStream* stream);
286
287 // Printing
288 void print_on(outputStream* st) const;
289 };
290
291 class ConstantDoubleValue: public ScopeValue {
292 private:
293 jdouble _value;
294 public:
295 ConstantDoubleValue(jdouble value) { _value = value; }
296 jdouble value() const { return _value; }
297 bool is_constant_double() const { return true; }
298 bool equals(ScopeValue* other) const { return false; }
299
300 // Serialization of debugging information
301 ConstantDoubleValue(DebugInfoReadStream* stream);
302 void write_on(DebugInfoWriteStream* stream);
303
304 // Printing
305 void print_on(outputStream* st) const;
306 };
307
308 // A ConstantOopWriteValue is created by the compiler to
309 // be written as debugging information.
310
311 class ConstantOopWriteValue: public ScopeValue {
312 private:
313 jobject _value;
314 public:
315 ConstantOopWriteValue(jobject value) { _value = value; }
316 jobject value() const { return _value; }
317 bool is_constant_oop() const { return true; }
318 bool equals(ScopeValue* other) const { return false; }
319
320 // Serialization of debugging information
321 void write_on(DebugInfoWriteStream* stream);
322
323 // Printing
324 void print_on(outputStream* st) const;
325 };
326
327 // A ConstantOopReadValue is created by the VM when reading
328 // debug information
329
330 class ConstantOopReadValue: public ScopeValue {
331 private:
332 Handle _value;
333 public:
334 Handle value() const { return _value; }
335 bool is_constant_oop() const { return true; }
336 bool equals(ScopeValue* other) const { return false; }
337
338 // Serialization of debugging information
339 ConstantOopReadValue(DebugInfoReadStream* stream);
340 void write_on(DebugInfoWriteStream* stream);
341
342 // Printing
343 void print_on(outputStream* st) const;
344 };
345
346 // MonitorValue describes the pair used for monitor_enter and monitor_exit.
347
348 class MonitorValue: public ResourceObj {
349 private:
350 ScopeValue* _owner;
351 Location _basic_lock;
352 bool _eliminated;
353 public:
354 // Constructor
355 MonitorValue(ScopeValue* owner, Location basic_lock, bool eliminated = false);
356
357 // Accessors
358 ScopeValue* owner() const { return _owner; }
359 Location basic_lock() const { return _basic_lock; }
360 bool eliminated() const { return _eliminated; }
361
362 // Serialization of debugging information
363 MonitorValue(DebugInfoReadStream* stream);
364 void write_on(DebugInfoWriteStream* stream);
365
366 // Printing
367 void print_on(outputStream* st) const;
368 };
369
370 // DebugInfoReadStream specializes CompressedReadStream for reading
371 // debugging information. Used by ScopeDesc.
372
373 class DebugInfoReadStream : public CompressedReadStream {
374 private:
375 const CompiledMethod* _code;
376 const CompiledMethod* code() const { return _code; }
377 GrowableArray<ScopeValue*>* _obj_pool;
378 public:
379 DebugInfoReadStream(const CompiledMethod* code, int offset, GrowableArray<ScopeValue*>* obj_pool = nullptr) :
380 CompressedReadStream(code->scopes_data_begin(), offset) {
381 _code = code;
382 _obj_pool = obj_pool;
383
384 } ;
385
386 oop read_oop();
387 Method* read_method() {
388 Method* o = (Method*)(code()->metadata_at(read_int()));
389 // is_metadata() is a faster check than is_metaspace_object()
390 assert(o == nullptr || o->is_metadata(), "meta data only");
391 return o;
392 }
393 ScopeValue* read_object_value(bool is_auto_box);
394 ScopeValue* read_object_merge_value();
395 ScopeValue* get_cached_object();
396 // BCI encoding is mostly unsigned, but -1 is a distinguished value
397 int read_bci() { return read_int() + InvocationEntryBci; }
398 };
399
400 // DebugInfoWriteStream specializes CompressedWriteStream for
401 // writing debugging information. Used by ScopeDescRecorder.
402
403 class DebugInfoWriteStream : public CompressedWriteStream {
404 private:
405 DebugInformationRecorder* _recorder;
406 DebugInformationRecorder* recorder() const { return _recorder; }
407 public:
408 DebugInfoWriteStream(DebugInformationRecorder* recorder, int initial_size);
409 void write_handle(jobject h);
410 void write_bci(int bci) { write_int(bci - InvocationEntryBci); }
411
412 void write_metadata(Metadata* m);
413 };
414
415 #endif // SHARE_CODE_DEBUGINFO_HPP