1 /*
2 * Copyright (c) 2005, 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/symbolTable.hpp"
26 #include "classfile/vmClasses.hpp"
27 #include "interpreter/bytecodeStream.hpp"
28 #include "memory/universe.hpp"
29 #include "oops/bsmAttribute.inline.hpp"
30 #include "oops/constantPool.inline.hpp"
31 #include "oops/fieldStreams.inline.hpp"
32 #include "oops/instanceKlass.inline.hpp"
33 #include "oops/recordComponent.hpp"
34 #include "prims/jvmtiClassFileReconstituter.hpp"
35 #include "runtime/handles.inline.hpp"
36 #include "runtime/signature.hpp"
37 #include "utilities/bytes.hpp"
38 #include "utilities/checkedCast.hpp"
39
40 // FIXME: add Deprecated attribute
41 // FIXME: fix Synthetic attribute
42 // FIXME: per Serguei, add error return handling for ConstantPool::copy_cpool_bytes()
43
44 JvmtiConstantPoolReconstituter::JvmtiConstantPoolReconstituter(InstanceKlass* ik) {
45 set_error(JVMTI_ERROR_NONE);
46 _ik = ik;
47 _cpool = constantPoolHandle(Thread::current(), ik->constants());
48 _symmap = new ConstantPool::SymbolHash();
49 _classmap = new ConstantPool::SymbolHash();
50 _cpool_size = _cpool->hash_entries_to(_symmap, _classmap);
51 if (_cpool_size == 0) {
52 set_error(JVMTI_ERROR_OUT_OF_MEMORY);
53 } else if (_cpool_size < 0) {
54 set_error(JVMTI_ERROR_INTERNAL);
55 }
56 }
57
58 // Write the field information portion of ClassFile structure
59 // JVMSpec| u2 fields_count;
60 // JVMSpec| field_info fields[fields_count];
61 void JvmtiClassFileReconstituter::write_field_infos() {
62 HandleMark hm(thread());
63 Array<AnnotationArray*>* fields_anno = ik()->fields_annotations();
64 Array<AnnotationArray*>* fields_type_anno = ik()->fields_type_annotations();
65
66 // Compute the real number of Java fields
67 int java_fields = ik()->java_fields_count();
68
69 write_u2(checked_cast<u2>(java_fields));
70 for (JavaFieldStream fs(ik()); !fs.done(); fs.next()) {
71 AccessFlags access_flags = fs.access_flags();
72 u2 name_index = fs.name_index();
73 u2 signature_index = fs.signature_index();
74 u2 initial_value_index = fs.initval_index();
75 guarantee(name_index != 0 && signature_index != 0, "bad constant pool index for field");
76 // int offset = ik()->field_offset( index );
77 u2 generic_signature_index = fs.generic_signature_index();
78 AnnotationArray* anno = fields_anno == nullptr ? nullptr : fields_anno->at(fs.index());
79 AnnotationArray* type_anno = fields_type_anno == nullptr ? nullptr : fields_type_anno->at(fs.index());
80
81 // JVMSpec| field_info {
82 // JVMSpec| u2 access_flags;
83 // JVMSpec| u2 name_index;
84 // JVMSpec| u2 descriptor_index;
85 // JVMSpec| u2 attributes_count;
86 // JVMSpec| attribute_info attributes[attributes_count];
87 // JVMSpec| }
88
89 write_u2(access_flags.as_field_flags());
90 write_u2(name_index);
91 write_u2(signature_index);
92 u2 attr_count = 0;
93 if (initial_value_index != 0) {
94 ++attr_count;
95 }
96 if (access_flags.is_synthetic()) {
97 // ++attr_count;
98 }
99 if (generic_signature_index != 0) {
100 ++attr_count;
101 }
102 if (anno != nullptr) {
103 ++attr_count; // has RuntimeVisibleAnnotations attribute
104 }
105 if (type_anno != nullptr) {
106 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
107 }
108
109 write_u2(attr_count);
110
111 if (initial_value_index != 0) {
112 write_attribute_name_index("ConstantValue");
113 write_u4(2); //length always 2
114 write_u2(initial_value_index);
115 }
116 if (access_flags.is_synthetic()) {
117 // write_synthetic_attribute();
118 }
119 if (generic_signature_index != 0) {
120 write_signature_attribute(generic_signature_index);
121 }
122 if (anno != nullptr) {
123 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
124 }
125 if (type_anno != nullptr) {
126 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
127 }
128 }
129 }
130
131 // Write Code attribute
132 // JVMSpec| Code_attribute {
133 // JVMSpec| u2 attribute_name_index;
134 // JVMSpec| u4 attribute_length;
135 // JVMSpec| u2 max_stack;
136 // JVMSpec| u2 max_locals;
137 // JVMSpec| u4 code_length;
138 // JVMSpec| u1 code[code_length];
139 // JVMSpec| u2 exception_table_length;
140 // JVMSpec| { u2 start_pc;
141 // JVMSpec| u2 end_pc;
142 // JVMSpec| u2 handler_pc;
143 // JVMSpec| u2 catch_type;
144 // JVMSpec| } exception_table[exception_table_length];
145 // JVMSpec| u2 attributes_count;
146 // JVMSpec| attribute_info attributes[attributes_count];
147 // JVMSpec| }
148 void JvmtiClassFileReconstituter::write_code_attribute(const methodHandle& method) {
149 ConstMethod* const_method = method->constMethod();
150 u2 line_num_cnt = 0;
151 int stackmap_len = 0;
152 u2 local_variable_table_length = 0;
153 u2 local_variable_type_table_length = 0;
154
155 // compute number and length of attributes
156 u2 attr_count = 0;
157 int attr_size = 0;
158 if (const_method->has_linenumber_table()) {
159 line_num_cnt = line_number_table_entries(method);
160 if (line_num_cnt != 0) {
161 ++attr_count;
162 // Compute the complete size of the line number table attribute:
163 // LineNumberTable_attribute {
164 // u2 attribute_name_index;
165 // u4 attribute_length;
166 // u2 line_number_table_length;
167 // { u2 start_pc;
168 // u2 line_number;
169 // } line_number_table[line_number_table_length];
170 // }
171 attr_size += 2 + 4 + 2 + line_num_cnt * (2 + 2);
172 }
173 }
174 if (method->has_stackmap_table()) {
175 stackmap_len = method->stackmap_data()->length();
176 if (stackmap_len != 0) {
177 ++attr_count;
178 // Compute the size of the stack map table attribute (VM stores raw):
179 // StackMapTable_attribute {
180 // u2 attribute_name_index;
181 // u4 attribute_length;
182 // u2 number_of_entries;
183 // stack_map_frame_entries[number_of_entries];
184 // }
185 attr_size += 2 + 4 + stackmap_len;
186 }
187 }
188 if (method->has_localvariable_table()) {
189 local_variable_table_length = method->localvariable_table_length();
190 if (local_variable_table_length != 0) {
191 ++attr_count;
192 // Compute the size of the local variable table attribute (VM stores raw):
193 // LocalVariableTable_attribute {
194 // u2 attribute_name_index;
195 // u4 attribute_length;
196 // u2 local_variable_table_length;
197 // {
198 // u2 start_pc;
199 // u2 length;
200 // u2 name_index;
201 // u2 descriptor_index;
202 // u2 index;
203 // }
204 attr_size += 2 + 4 + 2 + local_variable_table_length * (2 + 2 + 2 + 2 + 2);
205
206 // Local variables with generic signatures must have LVTT entries
207 LocalVariableTableElement *elem = method->localvariable_table_start();
208 for (int idx = 0; idx < local_variable_table_length; idx++) {
209 if (elem[idx].signature_cp_index != 0) {
210 local_variable_type_table_length++;
211 }
212 }
213
214 if (local_variable_type_table_length != 0) {
215 ++attr_count;
216 // Compute the size of the local variable type table attribute (VM stores raw):
217 // LocalVariableTypeTable_attribute {
218 // u2 attribute_name_index;
219 // u4 attribute_length;
220 // u2 local_variable_type_table_length;
221 // {
222 // u2 start_pc;
223 // u2 length;
224 // u2 name_index;
225 // u2 signature_index;
226 // u2 index;
227 // }
228 attr_size += 2 + 4 + 2 + local_variable_type_table_length * (2 + 2 + 2 + 2 + 2);
229 }
230 }
231 }
232
233 ExceptionTable exception_table(method());
234 u2 exception_table_length = exception_table.length();
235 int code_size = const_method->code_size();
236 int size =
237 2+2+4 + // max_stack, max_locals, code_length
238 code_size + // code
239 2 + // exception_table_length
240 (2+2+2+2) * exception_table_length + // exception_table
241 2 + // attributes_count
242 attr_size; // attributes
243
244 write_attribute_name_index("Code");
245 write_u4(size);
246 write_u2(method->verifier_max_stack());
247 write_u2(method->max_locals());
248 write_u4(code_size);
249 copy_bytecodes(method, (unsigned char*)writeable_address(code_size));
250 write_u2(exception_table_length);
251 for (int index = 0; index < exception_table_length; index++) {
252 write_u2(exception_table.start_pc(index));
253 write_u2(exception_table.end_pc(index));
254 write_u2(exception_table.handler_pc(index));
255 write_u2(exception_table.catch_type_index(index));
256 }
257 write_u2(attr_count);
258 if (line_num_cnt != 0) {
259 write_line_number_table_attribute(method, line_num_cnt);
260 }
261 if (stackmap_len != 0) {
262 write_stackmap_table_attribute(method, stackmap_len);
263 }
264 if (local_variable_table_length != 0) {
265 write_local_variable_table_attribute(method, local_variable_table_length);
266 }
267 if (local_variable_type_table_length != 0) {
268 write_local_variable_type_table_attribute(method, local_variable_type_table_length);
269 }
270 }
271
272 // Write Exceptions attribute
273 // JVMSpec| Exceptions_attribute {
274 // JVMSpec| u2 attribute_name_index;
275 // JVMSpec| u4 attribute_length;
276 // JVMSpec| u2 number_of_exceptions;
277 // JVMSpec| u2 exception_index_table[number_of_exceptions];
278 // JVMSpec| }
279 void JvmtiClassFileReconstituter::write_exceptions_attribute(ConstMethod* const_method) {
280 CheckedExceptionElement* checked_exceptions = const_method->checked_exceptions_start();
281 u2 checked_exceptions_length = const_method->checked_exceptions_length();
282 int size =
283 2 + // number_of_exceptions
284 2 * checked_exceptions_length; // exception_index_table
285
286 write_attribute_name_index("Exceptions");
287 write_u4(size);
288 write_u2(checked_exceptions_length);
289 for (int index = 0; index < checked_exceptions_length; index++) {
290 write_u2(checked_exceptions[index].class_cp_index);
291 }
292 }
293
294 // Write MethodParameters attribute
295 // JVMSpec| MethodParameters_attribute {
296 // JVMSpec| u2 attribute_name_index;
297 // JVMSpec| u4 attribute_length;
298 // JVMSpec| u1 parameters_count;
299 // JVMSpec| { u2 name_index;
300 // JVMSpec| u2 access_flags;
301 // JVMSpec| } parameters[parameters_count];
302 // JVMSpec| }
303 void JvmtiClassFileReconstituter::write_method_parameter_attribute(const ConstMethod* const_method) {
304 const MethodParametersElement *parameters = const_method->method_parameters_start();
305 int length = const_method->method_parameters_length();
306 assert(length <= max_jubyte, "must fit u1");
307 int size = 1 // parameters_count
308 + (2 + 2) * length; // parameters
309
310 write_attribute_name_index("MethodParameters");
311 write_u4(size);
312 write_u1((u1)length);
313 for (int index = 0; index < length; index++) {
314 write_u2(parameters[index].name_cp_index);
315 write_u2(parameters[index].flags);
316 }
317 }
318
319 // Write SourceFile attribute
320 // JVMSpec| SourceFile_attribute {
321 // JVMSpec| u2 attribute_name_index;
322 // JVMSpec| u4 attribute_length;
323 // JVMSpec| u2 sourcefile_index;
324 // JVMSpec| }
325 void JvmtiClassFileReconstituter::write_source_file_attribute() {
326 assert(ik()->source_file_name() != nullptr, "caller must check");
327
328 write_attribute_name_index("SourceFile");
329 write_u4(2); // always length 2
330 write_u2(symbol_to_cpool_index(ik()->source_file_name()));
331 }
332
333 // Write SourceDebugExtension attribute
334 // JSR45| SourceDebugExtension_attribute {
335 // JSR45| u2 attribute_name_index;
336 // JSR45| u4 attribute_length;
337 // JSR45| u1 debug_extension[attribute_length];
338 // JSR45| }
339 void JvmtiClassFileReconstituter::write_source_debug_extension_attribute() {
340 assert(ik()->source_debug_extension() != nullptr, "caller must check");
341
342 write_attribute_name_index("SourceDebugExtension");
343 int len = (int)strlen(ik()->source_debug_extension());
344 write_u4(len);
345 u1* ext = (u1*)ik()->source_debug_extension();
346 for (int i=0; i<len; i++) {
347 write_u1(ext[i]);
348 }
349 }
350
351 // Write (generic) Signature attribute
352 // JVMSpec| Signature_attribute {
353 // JVMSpec| u2 attribute_name_index;
354 // JVMSpec| u4 attribute_length;
355 // JVMSpec| u2 signature_index;
356 // JVMSpec| }
357 void JvmtiClassFileReconstituter::write_signature_attribute(u2 generic_signature_index) {
358 write_attribute_name_index("Signature");
359 write_u4(2); // always length 2
360 write_u2(generic_signature_index);
361 }
362
363 // Compute the number of entries in the InnerClasses attribute
364 u2 JvmtiClassFileReconstituter::inner_classes_attribute_length() {
365 InnerClassesIterator iter(ik());
366 return checked_cast<u2>(iter.length());
367 }
368
369 // Write an annotation attribute. The VM stores them in raw form, so all we need
370 // to do is add the attribute name and fill in the length.
371 // JSR202| *Annotations_attribute {
372 // JSR202| u2 attribute_name_index;
373 // JSR202| u4 attribute_length;
374 // JSR202| ...
375 // JSR202| }
376 void JvmtiClassFileReconstituter::write_annotations_attribute(const char* attr_name,
377 AnnotationArray* annos) {
378 u4 length = annos->length();
379 write_attribute_name_index(attr_name);
380 write_u4(length);
381 memcpy(writeable_address(length), annos->adr_at(0), length);
382 }
383
384 // BootstrapMethods_attribute {
385 // u2 attribute_name_index;
386 // u4 attribute_length;
387 // u2 num_bootstrap_methods;
388 // { u2 bootstrap_method_ref;
389 // u2 num_bootstrap_arguments;
390 // u2 bootstrap_arguments[num_bootstrap_arguments];
391 // } bootstrap_methods[num_bootstrap_methods];
392 // }
393 void JvmtiClassFileReconstituter::write_bootstrapmethod_attribute() {
394 write_attribute_name_index("BootstrapMethods");
395 u4 length = sizeof(u2) + // Size of num_bootstrap_methods
396 // The rest of the data for the attribute is exactly the u2s in the data array.
397 sizeof(u2) * cpool()->bsm_entries().array_length();
398 write_u4(length);
399
400 int num_bootstrap_methods = cpool()->bsm_entries().number_of_entries();
401 // write attribute
402 write_u2(checked_cast<u2>(num_bootstrap_methods));
403 for (int n = 0; n < num_bootstrap_methods; n++) {
404 BSMAttributeEntry* bsme = cpool()->bsm_attribute_entry(n);
405 u2 num_bootstrap_arguments = bsme->argument_count();
406 write_u2(bsme->bootstrap_method_index());
407 write_u2(num_bootstrap_arguments);
408 for (int arg = 0; arg < num_bootstrap_arguments; arg++) {
409 u2 bootstrap_argument = bsme->argument(arg);
410 write_u2(bootstrap_argument);
411 }
412 }
413 }
414
415 // NestHost_attribute {
416 // u2 attribute_name_index;
417 // u4 attribute_length;
418 // u2 host_class_index;
419 // }
420 void JvmtiClassFileReconstituter::write_nest_host_attribute() {
421 int length = sizeof(u2);
422 u2 host_class_index = ik()->nest_host_index();
423
424 write_attribute_name_index("NestHost");
425 write_u4(length);
426 write_u2(host_class_index);
427 }
428
429 // NestMembers_attribute {
430 // u2 attribute_name_index;
431 // u4 attribute_length;
432 // u2 number_of_classes;
433 // u2 classes[number_of_classes];
434 // }
435 void JvmtiClassFileReconstituter::write_nest_members_attribute() {
436 Array<u2>* nest_members = ik()->nest_members();
437 int number_of_classes = nest_members->length();
438 int length = sizeof(u2) * (1 + number_of_classes);
439
440 write_attribute_name_index("NestMembers");
441 write_u4(length);
442 write_u2(checked_cast<u2>(number_of_classes));
443 for (int i = 0; i < number_of_classes; i++) {
444 u2 class_cp_index = nest_members->at(i);
445 write_u2(class_cp_index);
446 }
447 }
448
449 // PermittedSubclasses {
450 // u2 attribute_name_index;
451 // u4 attribute_length;
452 // u2 number_of_classes;
453 // u2 classes[number_of_classes];
454 // }
455 void JvmtiClassFileReconstituter::write_permitted_subclasses_attribute() {
456 Array<u2>* permitted_subclasses = ik()->permitted_subclasses();
457 int number_of_classes = permitted_subclasses->length();
458 int length = sizeof(u2) * (1 + number_of_classes); // '1 +' is for number_of_classes field
459
460 write_attribute_name_index("PermittedSubclasses");
461 write_u4(length);
462 write_u2(checked_cast<u2>(number_of_classes));
463 for (int i = 0; i < number_of_classes; i++) {
464 u2 class_cp_index = permitted_subclasses->at(i);
465 write_u2(class_cp_index);
466 }
467 }
468
469 // LoadableDescriptors {
470 // u2 attribute_name_index;
471 // u4 attribute_length;
472 // u2 number_of_descriptors;
473 // u2 descriptors[number_of_descriptors];
474 // }
475 void JvmtiClassFileReconstituter::write_loadable_descriptors_attribute() {
476 Array<u2>* loadable_descriptors = ik()->loadable_descriptors();
477 int number_of_descriptors = loadable_descriptors->length();
478 int length = sizeof(u2) * (1 + number_of_descriptors); // '1 +' is for number_of_descriptors field
479
480 write_attribute_name_index("LoadableDescriptors");
481 write_u4(length);
482 write_u2(checked_cast<u2>(number_of_descriptors));
483 for (int i = 0; i < number_of_descriptors; i++) {
484 u2 utf8_index = loadable_descriptors->at(i);
485 write_u2(utf8_index);
486 }
487 }
488
489 // Record {
490 // u2 attribute_name_index;
491 // u4 attribute_length;
492 // u2 components_count;
493 // component_info components[components_count];
494 // }
495 // component_info {
496 // u2 name_index;
497 // u2 descriptor_index
498 // u2 attributes_count;
499 // attribute_info_attributes[attributes_count];
500 // }
501 void JvmtiClassFileReconstituter::write_record_attribute() {
502 Array<RecordComponent*>* components = ik()->record_components();
503 int number_of_components = components->length();
504
505 // Each component has a u2 for name, descr, attribute count
506 u4 length = checked_cast<u4>(sizeof(u2) + (sizeof(u2) * 3 * number_of_components));
507 for (int x = 0; x < number_of_components; x++) {
508 RecordComponent* component = components->at(x);
509 if (component->generic_signature_index() != 0) {
510 length += 8; // Signature attribute size
511 }
512 if (component->annotations() != nullptr) {
513 length += 6 + component->annotations()->length();
514 }
515 if (component->type_annotations() != nullptr) {
516 length += 6 + component->type_annotations()->length();
517 }
518 }
519
520 write_attribute_name_index("Record");
521 write_u4(length);
522 write_u2(checked_cast<u2>(number_of_components));
523 for (int i = 0; i < number_of_components; i++) {
524 RecordComponent* component = components->at(i);
525 write_u2(component->name_index());
526 write_u2(component->descriptor_index());
527 u2 attributes_count = (component->generic_signature_index() != 0 ? 1 : 0)
528 + (component->annotations() != nullptr ? 1 : 0)
529 + (component->type_annotations() != nullptr ? 1 : 0);
530
531 write_u2(attributes_count);
532 if (component->generic_signature_index() != 0) {
533 write_signature_attribute(component->generic_signature_index());
534 }
535 if (component->annotations() != nullptr) {
536 write_annotations_attribute("RuntimeVisibleAnnotations", component->annotations());
537 }
538 if (component->type_annotations() != nullptr) {
539 write_annotations_attribute("RuntimeVisibleTypeAnnotations", component->type_annotations());
540 }
541 }
542 }
543
544 // Write InnerClasses attribute
545 // JVMSpec| InnerClasses_attribute {
546 // JVMSpec| u2 attribute_name_index;
547 // JVMSpec| u4 attribute_length;
548 // JVMSpec| u2 number_of_classes;
549 // JVMSpec| { u2 inner_class_info_index;
550 // JVMSpec| u2 outer_class_info_index;
551 // JVMSpec| u2 inner_name_index;
552 // JVMSpec| u2 inner_class_access_flags;
553 // JVMSpec| } classes[number_of_classes];
554 // JVMSpec| }
555 void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {
556 InnerClassesIterator iter(ik());
557 guarantee(iter.length() != 0 && iter.length() == length,
558 "caller must check");
559 u2 entry_count = checked_cast<u2>(length / InstanceKlass::inner_class_next_offset);
560 u4 size = 2 + entry_count * (2+2+2+2);
561
562 write_attribute_name_index("InnerClasses");
563 write_u4(size);
564 write_u2(entry_count);
565 for (; !iter.done(); iter.next()) {
566 write_u2(iter.inner_class_info_index());
567 write_u2(iter.outer_class_info_index());
568 write_u2(iter.inner_name_index());
569 u2 flags = iter.inner_access_flags();
570 // ClassFileParser may add identity to inner class attributes, so remove it.
571 if (!ik()->supports_inline_types()) {
572 flags &= ~JVM_ACC_IDENTITY;;
573 }
574 write_u2(flags);
575 }
576 }
577
578 // Write Synthetic attribute
579 // JVMSpec| Synthetic_attribute {
580 // JVMSpec| u2 attribute_name_index;
581 // JVMSpec| u4 attribute_length;
582 // JVMSpec| }
583 void JvmtiClassFileReconstituter::write_synthetic_attribute() {
584 write_attribute_name_index("Synthetic");
585 write_u4(0); //length always zero
586 }
587
588 // Compute size of LineNumberTable
589 u2 JvmtiClassFileReconstituter::line_number_table_entries(const methodHandle& method) {
590 // The line number table is compressed so we don't know how big it is until decompressed.
591 // Decompression is really fast so we just do it twice.
592 u2 num_entries = 0;
593 CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
594 while (stream.read_pair()) {
595 num_entries++;
596 }
597 return num_entries;
598 }
599
600 // Write LineNumberTable attribute
601 // JVMSpec| LineNumberTable_attribute {
602 // JVMSpec| u2 attribute_name_index;
603 // JVMSpec| u4 attribute_length;
604 // JVMSpec| u2 line_number_table_length;
605 // JVMSpec| { u2 start_pc;
606 // JVMSpec| u2 line_number;
607 // JVMSpec| } line_number_table[line_number_table_length];
608 // JVMSpec| }
609 void JvmtiClassFileReconstituter::write_line_number_table_attribute(const methodHandle& method,
610 u2 num_entries) {
611
612 write_attribute_name_index("LineNumberTable");
613 write_u4(2 + num_entries * (2 + 2));
614 write_u2(num_entries);
615
616 CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
617 while (stream.read_pair()) {
618 write_u2(checked_cast<u2>(stream.bci()));
619 write_u2(checked_cast<u2>(stream.line()));
620 }
621 }
622
623 // Write LocalVariableTable attribute
624 // JVMSpec| LocalVariableTable_attribute {
625 // JVMSpec| u2 attribute_name_index;
626 // JVMSpec| u4 attribute_length;
627 // JVMSpec| u2 local_variable_table_length;
628 // JVMSpec| { u2 start_pc;
629 // JVMSpec| u2 length;
630 // JVMSpec| u2 name_index;
631 // JVMSpec| u2 descriptor_index;
632 // JVMSpec| u2 index;
633 // JVMSpec| } local_variable_table[local_variable_table_length];
634 // JVMSpec| }
635 void JvmtiClassFileReconstituter::write_local_variable_table_attribute(const methodHandle& method, u2 num_entries) {
636 write_attribute_name_index("LocalVariableTable");
637 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
638 write_u2(num_entries);
639
640 assert(method->localvariable_table_length() == num_entries, "just checking");
641
642 LocalVariableTableElement *elem = method->localvariable_table_start();
643 for (int j=0; j<method->localvariable_table_length(); j++) {
644 write_u2(elem->start_bci);
645 write_u2(elem->length);
646 write_u2(elem->name_cp_index);
647 write_u2(elem->descriptor_cp_index);
648 write_u2(elem->slot);
649 elem++;
650 }
651 }
652
653 // Write LocalVariableTypeTable attribute
654 // JVMSpec| LocalVariableTypeTable_attribute {
655 // JVMSpec| u2 attribute_name_index;
656 // JVMSpec| u4 attribute_length;
657 // JVMSpec| u2 local_variable_type_table_length;
658 // JVMSpec| { u2 start_pc;
659 // JVMSpec| u2 length;
660 // JVMSpec| u2 name_index;
661 // JVMSpec| u2 signature_index;
662 // JVMSpec| u2 index;
663 // JVMSpec| } local_variable_type_table[local_variable_type_table_length];
664 // JVMSpec| }
665 void JvmtiClassFileReconstituter::write_local_variable_type_table_attribute(const methodHandle& method, u2 num_entries) {
666 write_attribute_name_index("LocalVariableTypeTable");
667 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
668 write_u2(num_entries);
669
670 LocalVariableTableElement *elem = method->localvariable_table_start();
671 for (int j=0; j<method->localvariable_table_length(); j++) {
672 if (elem->signature_cp_index > 0) {
673 // Local variable has a generic signature - write LVTT attribute entry
674 write_u2(elem->start_bci);
675 write_u2(elem->length);
676 write_u2(elem->name_cp_index);
677 write_u2(elem->signature_cp_index);
678 write_u2(elem->slot);
679 num_entries--;
680 }
681 elem++;
682 }
683 assert(num_entries == 0, "just checking");
684 }
685
686 // Write stack map table attribute
687 // JSR-202| StackMapTable_attribute {
688 // JSR-202| u2 attribute_name_index;
689 // JSR-202| u4 attribute_length;
690 // JSR-202| u2 number_of_entries;
691 // JSR-202| stack_map_frame_entries[number_of_entries];
692 // JSR-202| }
693 void JvmtiClassFileReconstituter::write_stackmap_table_attribute(const methodHandle& method,
694 int stackmap_len) {
695
696 write_attribute_name_index("StackMapTable");
697 write_u4(stackmap_len);
698 memcpy(
699 writeable_address(stackmap_len),
700 (void*)(method->stackmap_data()->adr_at(0)),
701 stackmap_len);
702 }
703
704 // Write one method_info structure
705 // JVMSpec| method_info {
706 // JVMSpec| u2 access_flags;
707 // JVMSpec| u2 name_index;
708 // JVMSpec| u2 descriptor_index;
709 // JVMSpec| u2 attributes_count;
710 // JVMSpec| attribute_info attributes[attributes_count];
711 // JVMSpec| }
712 void JvmtiClassFileReconstituter::write_method_info(const methodHandle& method) {
713 AccessFlags access_flags = method->access_flags();
714 ConstMethod* const_method = method->constMethod();
715 u2 generic_signature_index = const_method->generic_signature_index();
716 AnnotationArray* anno = method->annotations();
717 AnnotationArray* param_anno = method->parameter_annotations();
718 AnnotationArray* default_anno = method->annotation_default();
719 AnnotationArray* type_anno = method->type_annotations();
720
721 // skip generated default interface methods
722 if (method->is_overpass()) {
723 return;
724 }
725
726 write_u2(access_flags.as_method_flags());
727 write_u2(const_method->name_index());
728 write_u2(const_method->signature_index());
729
730 // write attributes in the same order javac does, so we can test with byte for
731 // byte comparison
732 int attr_count = 0;
733 if (const_method->code_size() != 0) {
734 ++attr_count; // has Code attribute
735 }
736 if (const_method->has_checked_exceptions()) {
737 ++attr_count; // has Exceptions attribute
738 }
739 if (default_anno != nullptr) {
740 ++attr_count; // has AnnotationDefault attribute
741 }
742 if (const_method->has_method_parameters()) {
743 ++attr_count; // has MethodParameters attribute
744 }
745 // Deprecated attribute would go here
746 if (access_flags.is_synthetic()) { // FIXME
747 // ++attr_count;
748 }
749 if (generic_signature_index != 0) {
750 ++attr_count;
751 }
752 if (anno != nullptr) {
753 ++attr_count; // has RuntimeVisibleAnnotations attribute
754 }
755 if (param_anno != nullptr) {
756 ++attr_count; // has RuntimeVisibleParameterAnnotations attribute
757 }
758 if (type_anno != nullptr) {
759 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
760 }
761
762 write_u2(checked_cast<u2>(attr_count));
763 if (const_method->code_size() > 0) {
764 write_code_attribute(method);
765 }
766 if (const_method->has_checked_exceptions()) {
767 write_exceptions_attribute(const_method);
768 }
769 if (default_anno != nullptr) {
770 write_annotations_attribute("AnnotationDefault", default_anno);
771 }
772 if (const_method->has_method_parameters()) {
773 write_method_parameter_attribute(const_method);
774 }
775 // Deprecated attribute would go here
776 if (access_flags.is_synthetic()) {
777 // write_synthetic_attribute();
778 }
779 if (generic_signature_index != 0) {
780 write_signature_attribute(generic_signature_index);
781 }
782 if (anno != nullptr) {
783 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
784 }
785 if (param_anno != nullptr) {
786 write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno);
787 }
788 if (type_anno != nullptr) {
789 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
790 }
791 }
792
793 // Write the class attributes portion of ClassFile structure
794 // JVMSpec| u2 attributes_count;
795 // JVMSpec| attribute_info attributes[attributes_count];
796 void JvmtiClassFileReconstituter::write_class_attributes() {
797 u2 inner_classes_length = inner_classes_attribute_length();
798 Symbol* generic_signature = ik()->generic_signature();
799 AnnotationArray* anno = ik()->class_annotations();
800 AnnotationArray* type_anno = ik()->class_type_annotations();
801
802 u2 attr_count = 0;
803 if (generic_signature != nullptr) {
804 ++attr_count;
805 }
806 if (ik()->source_file_name() != nullptr) {
807 ++attr_count;
808 }
809 if (ik()->source_debug_extension() != nullptr) {
810 ++attr_count;
811 }
812 if (inner_classes_length > 0) {
813 ++attr_count;
814 }
815 if (anno != nullptr) {
816 ++attr_count; // has RuntimeVisibleAnnotations attribute
817 }
818 if (type_anno != nullptr) {
819 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
820 }
821 if (!cpool()->bsm_entries().is_empty()) {
822 ++attr_count;
823 }
824 if (ik()->nest_host_index() != 0) {
825 ++attr_count;
826 }
827 if (ik()->nest_members() != Universe::the_empty_short_array()) {
828 ++attr_count;
829 }
830 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) {
831 ++attr_count;
832 }
833 if (ik()->loadable_descriptors() != Universe::the_empty_short_array()) {
834 ++attr_count;
835 }
836 if (ik()->record_components() != nullptr) {
837 ++attr_count;
838 }
839
840 write_u2(attr_count);
841
842 if (generic_signature != nullptr) {
843 write_signature_attribute(symbol_to_cpool_index(generic_signature));
844 }
845 if (ik()->source_file_name() != nullptr) {
846 write_source_file_attribute();
847 }
848 if (ik()->source_debug_extension() != nullptr) {
849 write_source_debug_extension_attribute();
850 }
851 if (anno != nullptr) {
852 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
853 }
854 if (type_anno != nullptr) {
855 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
856 }
857 if (ik()->nest_host_index() != 0) {
858 write_nest_host_attribute();
859 }
860 if (ik()->nest_members() != Universe::the_empty_short_array()) {
861 write_nest_members_attribute();
862 }
863 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) {
864 write_permitted_subclasses_attribute();
865 }
866 if (ik()->loadable_descriptors() != Universe::the_empty_short_array()) {
867 write_loadable_descriptors_attribute();
868 }
869 if (ik()->record_components() != nullptr) {
870 write_record_attribute();
871 }
872 if (!cpool()->bsm_entries().is_empty()) {
873 write_bootstrapmethod_attribute();
874 }
875 if (inner_classes_length > 0) {
876 write_inner_classes_attribute(inner_classes_length);
877 }
878 }
879
880 // Write the method information portion of ClassFile structure
881 // JVMSpec| u2 methods_count;
882 // JVMSpec| method_info methods[methods_count];
883 void JvmtiClassFileReconstituter::write_method_infos() {
884 HandleMark hm(thread());
885 Array<Method*>* methods = ik()->methods();
886 int num_methods = methods->length();
887 int num_overpass = 0;
888
889 // count the generated default interface methods
890 // these will not be re-created by write_method_info
891 // and should not be included in the total count
892 for (int index = 0; index < num_methods; index++) {
893 Method* method = methods->at(index);
894 if (method->is_overpass()) {
895 num_overpass++;
896 }
897 }
898
899 write_u2(checked_cast<u2>(num_methods - num_overpass));
900 if (JvmtiExport::can_maintain_original_method_order()) {
901 int index;
902 int original_index;
903 intArray method_order(num_methods, num_methods, 0);
904
905 // invert the method order mapping
906 for (index = 0; index < num_methods; index++) {
907 original_index = ik()->method_ordering()->at(index);
908 assert(original_index >= 0 && original_index < num_methods,
909 "invalid original method index");
910 method_order.at_put(original_index, index);
911 }
912
913 // write in original order
914 for (original_index = 0; original_index < num_methods; original_index++) {
915 index = method_order.at(original_index);
916 methodHandle method(thread(), methods->at(index));
917 write_method_info(method);
918 }
919 } else {
920 // method order not preserved just dump the method infos
921 for (int index = 0; index < num_methods; index++) {
922 methodHandle method(thread(), methods->at(index));
923 write_method_info(method);
924 }
925 }
926 }
927
928 void JvmtiClassFileReconstituter::write_class_file_format() {
929 ReallocMark();
930
931 // JVMSpec| ClassFile {
932 // JVMSpec| u4 magic;
933 write_u4(0xCAFEBABE);
934
935 // JVMSpec| u2 minor_version;
936 // JVMSpec| u2 major_version;
937 write_u2(ik()->minor_version());
938 u2 major = ik()->major_version();
939 write_u2(major);
940
941 // JVMSpec| u2 constant_pool_count;
942 // JVMSpec| cp_info constant_pool[constant_pool_count-1];
943 write_u2(checked_cast<u2>(cpool()->length()));
944 copy_cpool_bytes(writeable_address(cpool_size()));
945
946 // JVMSpec| u2 access_flags;
947 write_u2(ik()->access_flags().as_class_flags());
948
949 // JVMSpec| u2 this_class;
950 // JVMSpec| u2 super_class;
951 write_u2(class_symbol_to_cpool_index(ik()->name()));
952 Klass* super_class = ik()->super();
953 write_u2(super_class == nullptr? 0 : // zero for java.lang.Object
954 class_symbol_to_cpool_index(super_class->name()));
955
956 // JVMSpec| u2 interfaces_count;
957 // JVMSpec| u2 interfaces[interfaces_count];
958 Array<InstanceKlass*>* interfaces = ik()->local_interfaces();
959 int num_interfaces = interfaces->length();
960 write_u2(checked_cast<u2>(num_interfaces));
961 for (int index = 0; index < num_interfaces; index++) {
962 HandleMark hm(thread());
963 InstanceKlass* iik = interfaces->at(index);
964 write_u2(class_symbol_to_cpool_index(iik->name()));
965 }
966
967 // JVMSpec| u2 fields_count;
968 // JVMSpec| field_info fields[fields_count];
969 write_field_infos();
970
971 // JVMSpec| u2 methods_count;
972 // JVMSpec| method_info methods[methods_count];
973 write_method_infos();
974
975 // JVMSpec| u2 attributes_count;
976 // JVMSpec| attribute_info attributes[attributes_count];
977 // JVMSpec| } /* end ClassFile 8?
978 write_class_attributes();
979 }
980
981 address JvmtiClassFileReconstituter::writeable_address(size_t size) {
982 size_t used_size = _buffer_ptr - _buffer;
983 if (size + used_size >= _buffer_size) {
984 // compute the new buffer size: must be at least twice as big as before
985 // plus whatever new is being used; then convert to nice clean block boundary
986 size_t new_buffer_size = (size + _buffer_size*2 + 1) / initial_buffer_size
987 * initial_buffer_size;
988
989 // VM goes belly-up if the memory isn't available, so cannot do OOM processing
990 _buffer = REALLOC_RESOURCE_ARRAY(u1, _buffer, _buffer_size, new_buffer_size);
991 _buffer_size = new_buffer_size;
992 _buffer_ptr = _buffer + used_size;
993 }
994 u1* ret_ptr = _buffer_ptr;
995 _buffer_ptr += size;
996 return ret_ptr;
997 }
998
999 void JvmtiClassFileReconstituter::write_attribute_name_index(const char* name) {
1000 TempNewSymbol sym = SymbolTable::probe(name, (int)strlen(name));
1001 assert(sym != nullptr, "attribute name symbol not found");
1002 u2 attr_name_index = symbol_to_cpool_index(sym);
1003 assert(attr_name_index != 0, "attribute name symbol not in constant pool");
1004 write_u2(attr_name_index);
1005 }
1006
1007 void JvmtiClassFileReconstituter::write_u1(u1 x) {
1008 *writeable_address(1) = x;
1009 }
1010
1011 void JvmtiClassFileReconstituter::write_u2(u2 x) {
1012 Bytes::put_Java_u2(writeable_address(2), x);
1013 }
1014
1015 void JvmtiClassFileReconstituter::write_u4(u4 x) {
1016 Bytes::put_Java_u4(writeable_address(4), x);
1017 }
1018
1019 void JvmtiClassFileReconstituter::write_u8(u8 x) {
1020 Bytes::put_Java_u8(writeable_address(8), x);
1021 }
1022
1023 void JvmtiClassFileReconstituter::copy_bytecodes(const methodHandle& mh,
1024 unsigned char* bytecodes) {
1025 // We must copy bytecodes only from linked classes.
1026 // Being linked guarantees we are not getting bytecodes at
1027 // the same time the linking process is rewriting them.
1028 guarantee(mh->method_holder()->is_linked(), "Bytecodes must be copied from a linked class");
1029
1030 // use a BytecodeStream to iterate over the bytecodes. JVM/fast bytecodes
1031 // and the breakpoint bytecode are converted to their original bytecodes.
1032
1033 BytecodeStream bs(mh);
1034
1035 unsigned char* p = bytecodes;
1036 Bytecodes::Code code;
1037 bool is_rewritten = mh->method_holder()->is_rewritten();
1038
1039 while ((code = bs.next()) >= 0) {
1040 assert(Bytecodes::is_java_code(code), "sanity check");
1041 assert(code != Bytecodes::_breakpoint, "sanity check");
1042
1043 // length of bytecode (mnemonic + operands)
1044 address bcp = bs.bcp();
1045 int len = bs.instruction_size();
1046 assert(len > 0, "length must be > 0");
1047
1048 // copy the bytecodes
1049 *p = (unsigned char) (bs.is_wide()? Bytecodes::_wide : code);
1050 if (len > 1) {
1051 memcpy(p+1, bcp+1, len-1);
1052 }
1053
1054 // During linking the get/put and invoke instructions are rewritten
1055 // with an index into the constant pool cache. The original constant
1056 // pool index must be returned to caller. Rewrite the index.
1057 if (is_rewritten && len > 1) {
1058 bool is_wide = false;
1059 switch (code) {
1060 case Bytecodes::_getstatic : // fall through
1061 case Bytecodes::_putstatic : // fall through
1062 case Bytecodes::_getfield : // fall through
1063 case Bytecodes::_putfield : {
1064 int field_index = Bytes::get_native_u2(bcp+1);
1065 u2 pool_index = mh->constants()->resolved_field_entry_at(field_index)->constant_pool_index();
1066 assert(pool_index < mh->constants()->length(), "sanity check");
1067 Bytes::put_Java_u2((address)(p+1), pool_index); // java byte ordering
1068 break;
1069 }
1070 case Bytecodes::_invokevirtual : // fall through
1071 case Bytecodes::_invokespecial : // fall through
1072 case Bytecodes::_invokestatic : // fall through
1073 case Bytecodes::_invokedynamic : // fall through
1074 case Bytecodes::_invokeinterface : {
1075 assert(len == 3 ||
1076 (code == Bytecodes::_invokeinterface && len == 5) ||
1077 (code == Bytecodes::_invokedynamic && len == 5),
1078 "sanity check");
1079
1080 int cpci = Bytes::get_native_u2(bcp+1);
1081 bool is_invokedynamic = (code == Bytecodes::_invokedynamic);
1082 int pool_index;
1083 if (is_invokedynamic) {
1084 cpci = Bytes::get_native_u4(bcp+1);
1085 pool_index = mh->constants()->resolved_indy_entry_at(cpci)->constant_pool_index();
1086 } else {
1087 // cache cannot be pre-fetched since some classes won't have it yet
1088 pool_index = mh->constants()->resolved_method_entry_at(cpci)->constant_pool_index();
1089 }
1090 assert(pool_index < mh->constants()->length(), "sanity check");
1091 Bytes::put_Java_u2((address)(p+1), (u2)pool_index); // java byte ordering
1092 if (is_invokedynamic) *(p+3) = *(p+4) = 0;
1093 break;
1094 }
1095 case Bytecodes::_ldc_w:
1096 is_wide = true; // fall through
1097 case Bytecodes::_ldc: {
1098 if (bs.raw_code() == Bytecodes::_fast_aldc || bs.raw_code() == Bytecodes::_fast_aldc_w) {
1099 int cpci = is_wide ? Bytes::get_native_u2(bcp+1) : (u1)(*(bcp+1));
1100 int i = mh->constants()->object_to_cp_index(cpci);
1101 assert(i < mh->constants()->length(), "sanity check");
1102 if (is_wide) {
1103 Bytes::put_Java_u2((address)(p+1), (u2)i); // java byte ordering
1104 } else {
1105 *(p+1) = (u1)i;
1106 }
1107 }
1108 break;
1109 }
1110 default:
1111 break;
1112 }
1113 }
1114
1115 p += len;
1116 }
1117 }