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/constantPool.inline.hpp"
30 #include "oops/fieldStreams.inline.hpp"
31 #include "oops/instanceKlass.inline.hpp"
32 #include "oops/recordComponent.hpp"
33 #include "prims/jvmtiClassFileReconstituter.hpp"
34 #include "runtime/handles.inline.hpp"
35 #include "runtime/signature.hpp"
36 #include "utilities/bytes.hpp"
37 #include "utilities/checkedCast.hpp"
38
39 // FIXME: add Deprecated attribute
40 // FIXME: fix Synthetic attribute
41 // FIXME: per Serguei, add error return handling for ConstantPool::copy_cpool_bytes()
42
43 JvmtiConstantPoolReconstituter::JvmtiConstantPoolReconstituter(InstanceKlass* ik) {
44 set_error(JVMTI_ERROR_NONE);
45 _ik = ik;
46 _cpool = constantPoolHandle(Thread::current(), ik->constants());
47 _symmap = new ConstantPool::SymbolHash();
48 _classmap = new ConstantPool::SymbolHash();
49 _cpool_size = _cpool->hash_entries_to(_symmap, _classmap);
50 if (_cpool_size == 0) {
51 set_error(JVMTI_ERROR_OUT_OF_MEMORY);
52 } else if (_cpool_size < 0) {
53 set_error(JVMTI_ERROR_INTERNAL);
54 }
55 }
56
57 // Write the field information portion of ClassFile structure
58 // JVMSpec| u2 fields_count;
59 // JVMSpec| field_info fields[fields_count];
60 void JvmtiClassFileReconstituter::write_field_infos() {
61 HandleMark hm(thread());
62 Array<AnnotationArray*>* fields_anno = ik()->fields_annotations();
63 Array<AnnotationArray*>* fields_type_anno = ik()->fields_type_annotations();
64
65 // Compute the real number of Java fields
66 int java_fields = ik()->java_fields_count();
67
68 write_u2(checked_cast<u2>(java_fields));
69 for (JavaFieldStream fs(ik()); !fs.done(); fs.next()) {
70 AccessFlags access_flags = fs.access_flags();
71 u2 name_index = fs.name_index();
72 u2 signature_index = fs.signature_index();
73 u2 initial_value_index = fs.initval_index();
74 guarantee(name_index != 0 && signature_index != 0, "bad constant pool index for field");
75 // int offset = ik()->field_offset( index );
76 u2 generic_signature_index = fs.generic_signature_index();
77 AnnotationArray* anno = fields_anno == nullptr ? nullptr : fields_anno->at(fs.index());
78 AnnotationArray* type_anno = fields_type_anno == nullptr ? nullptr : fields_type_anno->at(fs.index());
79
80 // JVMSpec| field_info {
81 // JVMSpec| u2 access_flags;
82 // JVMSpec| u2 name_index;
83 // JVMSpec| u2 descriptor_index;
84 // JVMSpec| u2 attributes_count;
85 // JVMSpec| attribute_info attributes[attributes_count];
86 // JVMSpec| }
87
88 write_u2(access_flags.as_field_flags());
89 write_u2(name_index);
90 write_u2(signature_index);
91 u2 attr_count = 0;
92 if (initial_value_index != 0) {
93 ++attr_count;
94 }
95 if (access_flags.is_synthetic()) {
96 // ++attr_count;
97 }
98 if (generic_signature_index != 0) {
99 ++attr_count;
100 }
101 if (anno != nullptr) {
102 ++attr_count; // has RuntimeVisibleAnnotations attribute
103 }
104 if (type_anno != nullptr) {
105 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
106 }
107
108 write_u2(attr_count);
109
110 if (initial_value_index != 0) {
111 write_attribute_name_index("ConstantValue");
112 write_u4(2); //length always 2
113 write_u2(initial_value_index);
114 }
115 if (access_flags.is_synthetic()) {
116 // write_synthetic_attribute();
117 }
118 if (generic_signature_index != 0) {
119 write_signature_attribute(generic_signature_index);
120 }
121 if (anno != nullptr) {
122 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
123 }
124 if (type_anno != nullptr) {
125 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
126 }
127 }
128 }
129
130 // Write Code attribute
131 // JVMSpec| Code_attribute {
132 // JVMSpec| u2 attribute_name_index;
133 // JVMSpec| u4 attribute_length;
134 // JVMSpec| u2 max_stack;
135 // JVMSpec| u2 max_locals;
136 // JVMSpec| u4 code_length;
137 // JVMSpec| u1 code[code_length];
138 // JVMSpec| u2 exception_table_length;
139 // JVMSpec| { u2 start_pc;
140 // JVMSpec| u2 end_pc;
141 // JVMSpec| u2 handler_pc;
142 // JVMSpec| u2 catch_type;
143 // JVMSpec| } exception_table[exception_table_length];
144 // JVMSpec| u2 attributes_count;
145 // JVMSpec| attribute_info attributes[attributes_count];
146 // JVMSpec| }
147 void JvmtiClassFileReconstituter::write_code_attribute(const methodHandle& method) {
148 ConstMethod* const_method = method->constMethod();
149 u2 line_num_cnt = 0;
150 int stackmap_len = 0;
151 u2 local_variable_table_length = 0;
152 u2 local_variable_type_table_length = 0;
153
154 // compute number and length of attributes
155 u2 attr_count = 0;
156 int attr_size = 0;
157 if (const_method->has_linenumber_table()) {
158 line_num_cnt = line_number_table_entries(method);
159 if (line_num_cnt != 0) {
160 ++attr_count;
161 // Compute the complete size of the line number table attribute:
162 // LineNumberTable_attribute {
163 // u2 attribute_name_index;
164 // u4 attribute_length;
165 // u2 line_number_table_length;
166 // { u2 start_pc;
167 // u2 line_number;
168 // } line_number_table[line_number_table_length];
169 // }
170 attr_size += 2 + 4 + 2 + line_num_cnt * (2 + 2);
171 }
172 }
173 if (method->has_stackmap_table()) {
174 stackmap_len = method->stackmap_data()->length();
175 if (stackmap_len != 0) {
176 ++attr_count;
177 // Compute the size of the stack map table attribute (VM stores raw):
178 // StackMapTable_attribute {
179 // u2 attribute_name_index;
180 // u4 attribute_length;
181 // u2 number_of_entries;
182 // stack_map_frame_entries[number_of_entries];
183 // }
184 attr_size += 2 + 4 + stackmap_len;
185 }
186 }
187 if (method->has_localvariable_table()) {
188 local_variable_table_length = method->localvariable_table_length();
189 if (local_variable_table_length != 0) {
190 ++attr_count;
191 // Compute the size of the local variable table attribute (VM stores raw):
192 // LocalVariableTable_attribute {
193 // u2 attribute_name_index;
194 // u4 attribute_length;
195 // u2 local_variable_table_length;
196 // {
197 // u2 start_pc;
198 // u2 length;
199 // u2 name_index;
200 // u2 descriptor_index;
201 // u2 index;
202 // }
203 attr_size += 2 + 4 + 2 + local_variable_table_length * (2 + 2 + 2 + 2 + 2);
204
205 // Local variables with generic signatures must have LVTT entries
206 LocalVariableTableElement *elem = method->localvariable_table_start();
207 for (int idx = 0; idx < local_variable_table_length; idx++) {
208 if (elem[idx].signature_cp_index != 0) {
209 local_variable_type_table_length++;
210 }
211 }
212
213 if (local_variable_type_table_length != 0) {
214 ++attr_count;
215 // Compute the size of the local variable type table attribute (VM stores raw):
216 // LocalVariableTypeTable_attribute {
217 // u2 attribute_name_index;
218 // u4 attribute_length;
219 // u2 local_variable_type_table_length;
220 // {
221 // u2 start_pc;
222 // u2 length;
223 // u2 name_index;
224 // u2 signature_index;
225 // u2 index;
226 // }
227 attr_size += 2 + 4 + 2 + local_variable_type_table_length * (2 + 2 + 2 + 2 + 2);
228 }
229 }
230 }
231
232 ExceptionTable exception_table(method());
233 u2 exception_table_length = exception_table.length();
234 int code_size = const_method->code_size();
235 int size =
236 2+2+4 + // max_stack, max_locals, code_length
237 code_size + // code
238 2 + // exception_table_length
239 (2+2+2+2) * exception_table_length + // exception_table
240 2 + // attributes_count
241 attr_size; // attributes
242
243 write_attribute_name_index("Code");
244 write_u4(size);
245 write_u2(method->verifier_max_stack());
246 write_u2(method->max_locals());
247 write_u4(code_size);
248 copy_bytecodes(method, (unsigned char*)writeable_address(code_size));
249 write_u2(exception_table_length);
250 for (int index = 0; index < exception_table_length; index++) {
251 write_u2(exception_table.start_pc(index));
252 write_u2(exception_table.end_pc(index));
253 write_u2(exception_table.handler_pc(index));
254 write_u2(exception_table.catch_type_index(index));
255 }
256 write_u2(attr_count);
257 if (line_num_cnt != 0) {
258 write_line_number_table_attribute(method, line_num_cnt);
259 }
260 if (stackmap_len != 0) {
261 write_stackmap_table_attribute(method, stackmap_len);
262 }
263 if (local_variable_table_length != 0) {
264 write_local_variable_table_attribute(method, local_variable_table_length);
265 }
266 if (local_variable_type_table_length != 0) {
267 write_local_variable_type_table_attribute(method, local_variable_type_table_length);
268 }
269 }
270
271 // Write Exceptions attribute
272 // JVMSpec| Exceptions_attribute {
273 // JVMSpec| u2 attribute_name_index;
274 // JVMSpec| u4 attribute_length;
275 // JVMSpec| u2 number_of_exceptions;
276 // JVMSpec| u2 exception_index_table[number_of_exceptions];
277 // JVMSpec| }
278 void JvmtiClassFileReconstituter::write_exceptions_attribute(ConstMethod* const_method) {
279 CheckedExceptionElement* checked_exceptions = const_method->checked_exceptions_start();
280 u2 checked_exceptions_length = const_method->checked_exceptions_length();
281 int size =
282 2 + // number_of_exceptions
283 2 * checked_exceptions_length; // exception_index_table
284
285 write_attribute_name_index("Exceptions");
286 write_u4(size);
287 write_u2(checked_exceptions_length);
288 for (int index = 0; index < checked_exceptions_length; index++) {
289 write_u2(checked_exceptions[index].class_cp_index);
290 }
291 }
292
293 // Write MethodParameters attribute
294 // JVMSpec| MethodParameters_attribute {
295 // JVMSpec| u2 attribute_name_index;
296 // JVMSpec| u4 attribute_length;
297 // JVMSpec| u1 parameters_count;
298 // JVMSpec| { u2 name_index;
299 // JVMSpec| u2 access_flags;
300 // JVMSpec| } parameters[parameters_count];
301 // JVMSpec| }
302 void JvmtiClassFileReconstituter::write_method_parameter_attribute(const ConstMethod* const_method) {
303 const MethodParametersElement *parameters = const_method->method_parameters_start();
304 int length = const_method->method_parameters_length();
305 assert(length <= max_jubyte, "must fit u1");
306 int size = 1 // parameters_count
307 + (2 + 2) * length; // parameters
308
309 write_attribute_name_index("MethodParameters");
310 write_u4(size);
311 write_u1((u1)length);
312 for (int index = 0; index < length; index++) {
313 write_u2(parameters[index].name_cp_index);
314 write_u2(parameters[index].flags);
315 }
316 }
317
318 // Write SourceFile attribute
319 // JVMSpec| SourceFile_attribute {
320 // JVMSpec| u2 attribute_name_index;
321 // JVMSpec| u4 attribute_length;
322 // JVMSpec| u2 sourcefile_index;
323 // JVMSpec| }
324 void JvmtiClassFileReconstituter::write_source_file_attribute() {
325 assert(ik()->source_file_name() != nullptr, "caller must check");
326
327 write_attribute_name_index("SourceFile");
328 write_u4(2); // always length 2
329 write_u2(symbol_to_cpool_index(ik()->source_file_name()));
330 }
331
332 // Write SourceDebugExtension attribute
333 // JSR45| SourceDebugExtension_attribute {
334 // JSR45| u2 attribute_name_index;
335 // JSR45| u4 attribute_length;
336 // JSR45| u1 debug_extension[attribute_length];
337 // JSR45| }
338 void JvmtiClassFileReconstituter::write_source_debug_extension_attribute() {
339 assert(ik()->source_debug_extension() != nullptr, "caller must check");
340
341 write_attribute_name_index("SourceDebugExtension");
342 int len = (int)strlen(ik()->source_debug_extension());
343 write_u4(len);
344 u1* ext = (u1*)ik()->source_debug_extension();
345 for (int i=0; i<len; i++) {
346 write_u1(ext[i]);
347 }
348 }
349
350 // Write (generic) Signature attribute
351 // JVMSpec| Signature_attribute {
352 // JVMSpec| u2 attribute_name_index;
353 // JVMSpec| u4 attribute_length;
354 // JVMSpec| u2 signature_index;
355 // JVMSpec| }
356 void JvmtiClassFileReconstituter::write_signature_attribute(u2 generic_signature_index) {
357 write_attribute_name_index("Signature");
358 write_u4(2); // always length 2
359 write_u2(generic_signature_index);
360 }
361
362 // Compute the number of entries in the InnerClasses attribute
363 u2 JvmtiClassFileReconstituter::inner_classes_attribute_length() {
364 InnerClassesIterator iter(ik());
365 return checked_cast<u2>(iter.length());
366 }
367
368 // Write an annotation attribute. The VM stores them in raw form, so all we need
369 // to do is add the attribute name and fill in the length.
370 // JSR202| *Annotations_attribute {
371 // JSR202| u2 attribute_name_index;
372 // JSR202| u4 attribute_length;
373 // JSR202| ...
374 // JSR202| }
375 void JvmtiClassFileReconstituter::write_annotations_attribute(const char* attr_name,
376 AnnotationArray* annos) {
377 u4 length = annos->length();
378 write_attribute_name_index(attr_name);
379 write_u4(length);
380 memcpy(writeable_address(length), annos->adr_at(0), length);
381 }
382
383 // BootstrapMethods_attribute {
384 // u2 attribute_name_index;
385 // u4 attribute_length;
386 // u2 num_bootstrap_methods;
387 // { u2 bootstrap_method_ref;
388 // u2 num_bootstrap_arguments;
389 // u2 bootstrap_arguments[num_bootstrap_arguments];
390 // } bootstrap_methods[num_bootstrap_methods];
391 // }
392 void JvmtiClassFileReconstituter::write_bootstrapmethod_attribute() {
393 Array<u2>* operands = cpool()->operands();
394 write_attribute_name_index("BootstrapMethods");
395 int num_bootstrap_methods = ConstantPool::operand_array_length(operands);
396
397 // calculate length of attribute
398 u4 length = sizeof(u2); // num_bootstrap_methods
399 for (int n = 0; n < num_bootstrap_methods; n++) {
400 u2 num_bootstrap_arguments = cpool()->bsm_attribute_entry(n)->argument_count();
401 length += sizeof(u2); // bootstrap_method_ref
402 length += sizeof(u2); // num_bootstrap_arguments
403 length += (u4)sizeof(u2) * num_bootstrap_arguments; // bootstrap_arguments[num_bootstrap_arguments]
404 }
405 write_u4(length);
406
407 // write attribute
408 write_u2(checked_cast<u2>(num_bootstrap_methods));
409 for (int n = 0; n < num_bootstrap_methods; n++) {
410 BSMAttributeEntry* bsme = cpool()->bsm_attribute_entry(n);
411 u2 num_bootstrap_arguments = bsme->argument_count();
412 write_u2(bsme->bootstrap_method_index());
413 write_u2(num_bootstrap_arguments);
414 for (int arg = 0; arg < num_bootstrap_arguments; arg++) {
415 u2 bootstrap_argument = bsme->argument_index(arg);
416 write_u2(bootstrap_argument);
417 }
418 }
419 }
420
421 // NestHost_attribute {
422 // u2 attribute_name_index;
423 // u4 attribute_length;
424 // u2 host_class_index;
425 // }
426 void JvmtiClassFileReconstituter::write_nest_host_attribute() {
427 int length = sizeof(u2);
428 u2 host_class_index = ik()->nest_host_index();
429
430 write_attribute_name_index("NestHost");
431 write_u4(length);
432 write_u2(host_class_index);
433 }
434
435 // NestMembers_attribute {
436 // u2 attribute_name_index;
437 // u4 attribute_length;
438 // u2 number_of_classes;
439 // u2 classes[number_of_classes];
440 // }
441 void JvmtiClassFileReconstituter::write_nest_members_attribute() {
442 Array<u2>* nest_members = ik()->nest_members();
443 int number_of_classes = nest_members->length();
444 int length = sizeof(u2) * (1 + number_of_classes);
445
446 write_attribute_name_index("NestMembers");
447 write_u4(length);
448 write_u2(checked_cast<u2>(number_of_classes));
449 for (int i = 0; i < number_of_classes; i++) {
450 u2 class_cp_index = nest_members->at(i);
451 write_u2(class_cp_index);
452 }
453 }
454
455 // PermittedSubclasses {
456 // u2 attribute_name_index;
457 // u4 attribute_length;
458 // u2 number_of_classes;
459 // u2 classes[number_of_classes];
460 // }
461 void JvmtiClassFileReconstituter::write_permitted_subclasses_attribute() {
462 Array<u2>* permitted_subclasses = ik()->permitted_subclasses();
463 int number_of_classes = permitted_subclasses->length();
464 int length = sizeof(u2) * (1 + number_of_classes); // '1 +' is for number_of_classes field
465
466 write_attribute_name_index("PermittedSubclasses");
467 write_u4(length);
468 write_u2(checked_cast<u2>(number_of_classes));
469 for (int i = 0; i < number_of_classes; i++) {
470 u2 class_cp_index = permitted_subclasses->at(i);
471 write_u2(class_cp_index);
472 }
473 }
474
475 // LoadableDescriptors {
476 // u2 attribute_name_index;
477 // u4 attribute_length;
478 // u2 number_of_descriptors;
479 // u2 descriptors[number_of_descriptors];
480 // }
481 void JvmtiClassFileReconstituter::write_loadable_descriptors_attribute() {
482 Array<u2>* loadable_descriptors = ik()->loadable_descriptors();
483 int number_of_descriptors = loadable_descriptors->length();
484 int length = sizeof(u2) * (1 + number_of_descriptors); // '1 +' is for number_of_descriptors field
485
486 write_attribute_name_index("LoadableDescriptors");
487 write_u4(length);
488 write_u2(checked_cast<u2>(number_of_descriptors));
489 for (int i = 0; i < number_of_descriptors; i++) {
490 u2 utf8_index = loadable_descriptors->at(i);
491 write_u2(utf8_index);
492 }
493 }
494
495 // Record {
496 // u2 attribute_name_index;
497 // u4 attribute_length;
498 // u2 components_count;
499 // component_info components[components_count];
500 // }
501 // component_info {
502 // u2 name_index;
503 // u2 descriptor_index
504 // u2 attributes_count;
505 // attribute_info_attributes[attributes_count];
506 // }
507 void JvmtiClassFileReconstituter::write_record_attribute() {
508 Array<RecordComponent*>* components = ik()->record_components();
509 int number_of_components = components->length();
510
511 // Each component has a u2 for name, descr, attribute count
512 u4 length = checked_cast<u4>(sizeof(u2) + (sizeof(u2) * 3 * number_of_components));
513 for (int x = 0; x < number_of_components; x++) {
514 RecordComponent* component = components->at(x);
515 if (component->generic_signature_index() != 0) {
516 length += 8; // Signature attribute size
517 }
518 if (component->annotations() != nullptr) {
519 length += 6 + component->annotations()->length();
520 }
521 if (component->type_annotations() != nullptr) {
522 length += 6 + component->type_annotations()->length();
523 }
524 }
525
526 write_attribute_name_index("Record");
527 write_u4(length);
528 write_u2(checked_cast<u2>(number_of_components));
529 for (int i = 0; i < number_of_components; i++) {
530 RecordComponent* component = components->at(i);
531 write_u2(component->name_index());
532 write_u2(component->descriptor_index());
533 u2 attributes_count = (component->generic_signature_index() != 0 ? 1 : 0)
534 + (component->annotations() != nullptr ? 1 : 0)
535 + (component->type_annotations() != nullptr ? 1 : 0);
536
537 write_u2(attributes_count);
538 if (component->generic_signature_index() != 0) {
539 write_signature_attribute(component->generic_signature_index());
540 }
541 if (component->annotations() != nullptr) {
542 write_annotations_attribute("RuntimeVisibleAnnotations", component->annotations());
543 }
544 if (component->type_annotations() != nullptr) {
545 write_annotations_attribute("RuntimeVisibleTypeAnnotations", component->type_annotations());
546 }
547 }
548 }
549
550 // Write InnerClasses attribute
551 // JVMSpec| InnerClasses_attribute {
552 // JVMSpec| u2 attribute_name_index;
553 // JVMSpec| u4 attribute_length;
554 // JVMSpec| u2 number_of_classes;
555 // JVMSpec| { u2 inner_class_info_index;
556 // JVMSpec| u2 outer_class_info_index;
557 // JVMSpec| u2 inner_name_index;
558 // JVMSpec| u2 inner_class_access_flags;
559 // JVMSpec| } classes[number_of_classes];
560 // JVMSpec| }
561 void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {
562 InnerClassesIterator iter(ik());
563 guarantee(iter.length() != 0 && iter.length() == length,
564 "caller must check");
565 u2 entry_count = checked_cast<u2>(length / InstanceKlass::inner_class_next_offset);
566 u4 size = 2 + entry_count * (2+2+2+2);
567
568 write_attribute_name_index("InnerClasses");
569 write_u4(size);
570 write_u2(entry_count);
571 for (; !iter.done(); iter.next()) {
572 write_u2(iter.inner_class_info_index());
573 write_u2(iter.outer_class_info_index());
574 write_u2(iter.inner_name_index());
575 u2 flags = iter.inner_access_flags();
576 // ClassFileParser may add identity to inner class attributes, so remove it.
577 if (!ik()->supports_inline_types()) {
578 flags &= ~JVM_ACC_IDENTITY;;
579 }
580 write_u2(flags);
581 }
582 }
583
584 // Write Synthetic attribute
585 // JVMSpec| Synthetic_attribute {
586 // JVMSpec| u2 attribute_name_index;
587 // JVMSpec| u4 attribute_length;
588 // JVMSpec| }
589 void JvmtiClassFileReconstituter::write_synthetic_attribute() {
590 write_attribute_name_index("Synthetic");
591 write_u4(0); //length always zero
592 }
593
594 // Compute size of LineNumberTable
595 u2 JvmtiClassFileReconstituter::line_number_table_entries(const methodHandle& method) {
596 // The line number table is compressed so we don't know how big it is until decompressed.
597 // Decompression is really fast so we just do it twice.
598 u2 num_entries = 0;
599 CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
600 while (stream.read_pair()) {
601 num_entries++;
602 }
603 return num_entries;
604 }
605
606 // Write LineNumberTable attribute
607 // JVMSpec| LineNumberTable_attribute {
608 // JVMSpec| u2 attribute_name_index;
609 // JVMSpec| u4 attribute_length;
610 // JVMSpec| u2 line_number_table_length;
611 // JVMSpec| { u2 start_pc;
612 // JVMSpec| u2 line_number;
613 // JVMSpec| } line_number_table[line_number_table_length];
614 // JVMSpec| }
615 void JvmtiClassFileReconstituter::write_line_number_table_attribute(const methodHandle& method,
616 u2 num_entries) {
617
618 write_attribute_name_index("LineNumberTable");
619 write_u4(2 + num_entries * (2 + 2));
620 write_u2(num_entries);
621
622 CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
623 while (stream.read_pair()) {
624 write_u2(checked_cast<u2>(stream.bci()));
625 write_u2(checked_cast<u2>(stream.line()));
626 }
627 }
628
629 // Write LocalVariableTable attribute
630 // JVMSpec| LocalVariableTable_attribute {
631 // JVMSpec| u2 attribute_name_index;
632 // JVMSpec| u4 attribute_length;
633 // JVMSpec| u2 local_variable_table_length;
634 // JVMSpec| { u2 start_pc;
635 // JVMSpec| u2 length;
636 // JVMSpec| u2 name_index;
637 // JVMSpec| u2 descriptor_index;
638 // JVMSpec| u2 index;
639 // JVMSpec| } local_variable_table[local_variable_table_length];
640 // JVMSpec| }
641 void JvmtiClassFileReconstituter::write_local_variable_table_attribute(const methodHandle& method, u2 num_entries) {
642 write_attribute_name_index("LocalVariableTable");
643 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
644 write_u2(num_entries);
645
646 assert(method->localvariable_table_length() == num_entries, "just checking");
647
648 LocalVariableTableElement *elem = method->localvariable_table_start();
649 for (int j=0; j<method->localvariable_table_length(); j++) {
650 write_u2(elem->start_bci);
651 write_u2(elem->length);
652 write_u2(elem->name_cp_index);
653 write_u2(elem->descriptor_cp_index);
654 write_u2(elem->slot);
655 elem++;
656 }
657 }
658
659 // Write LocalVariableTypeTable attribute
660 // JVMSpec| LocalVariableTypeTable_attribute {
661 // JVMSpec| u2 attribute_name_index;
662 // JVMSpec| u4 attribute_length;
663 // JVMSpec| u2 local_variable_type_table_length;
664 // JVMSpec| { u2 start_pc;
665 // JVMSpec| u2 length;
666 // JVMSpec| u2 name_index;
667 // JVMSpec| u2 signature_index;
668 // JVMSpec| u2 index;
669 // JVMSpec| } local_variable_type_table[local_variable_type_table_length];
670 // JVMSpec| }
671 void JvmtiClassFileReconstituter::write_local_variable_type_table_attribute(const methodHandle& method, u2 num_entries) {
672 write_attribute_name_index("LocalVariableTypeTable");
673 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
674 write_u2(num_entries);
675
676 LocalVariableTableElement *elem = method->localvariable_table_start();
677 for (int j=0; j<method->localvariable_table_length(); j++) {
678 if (elem->signature_cp_index > 0) {
679 // Local variable has a generic signature - write LVTT attribute entry
680 write_u2(elem->start_bci);
681 write_u2(elem->length);
682 write_u2(elem->name_cp_index);
683 write_u2(elem->signature_cp_index);
684 write_u2(elem->slot);
685 num_entries--;
686 }
687 elem++;
688 }
689 assert(num_entries == 0, "just checking");
690 }
691
692 // Write stack map table attribute
693 // JSR-202| StackMapTable_attribute {
694 // JSR-202| u2 attribute_name_index;
695 // JSR-202| u4 attribute_length;
696 // JSR-202| u2 number_of_entries;
697 // JSR-202| stack_map_frame_entries[number_of_entries];
698 // JSR-202| }
699 void JvmtiClassFileReconstituter::write_stackmap_table_attribute(const methodHandle& method,
700 int stackmap_len) {
701
702 write_attribute_name_index("StackMapTable");
703 write_u4(stackmap_len);
704 memcpy(
705 writeable_address(stackmap_len),
706 (void*)(method->stackmap_data()->adr_at(0)),
707 stackmap_len);
708 }
709
710 // Write one method_info structure
711 // JVMSpec| method_info {
712 // JVMSpec| u2 access_flags;
713 // JVMSpec| u2 name_index;
714 // JVMSpec| u2 descriptor_index;
715 // JVMSpec| u2 attributes_count;
716 // JVMSpec| attribute_info attributes[attributes_count];
717 // JVMSpec| }
718 void JvmtiClassFileReconstituter::write_method_info(const methodHandle& method) {
719 AccessFlags access_flags = method->access_flags();
720 ConstMethod* const_method = method->constMethod();
721 u2 generic_signature_index = const_method->generic_signature_index();
722 AnnotationArray* anno = method->annotations();
723 AnnotationArray* param_anno = method->parameter_annotations();
724 AnnotationArray* default_anno = method->annotation_default();
725 AnnotationArray* type_anno = method->type_annotations();
726
727 // skip generated default interface methods
728 if (method->is_overpass()) {
729 return;
730 }
731
732 write_u2(access_flags.as_method_flags());
733 write_u2(const_method->name_index());
734 write_u2(const_method->signature_index());
735
736 // write attributes in the same order javac does, so we can test with byte for
737 // byte comparison
738 int attr_count = 0;
739 if (const_method->code_size() != 0) {
740 ++attr_count; // has Code attribute
741 }
742 if (const_method->has_checked_exceptions()) {
743 ++attr_count; // has Exceptions attribute
744 }
745 if (default_anno != nullptr) {
746 ++attr_count; // has AnnotationDefault attribute
747 }
748 if (const_method->has_method_parameters()) {
749 ++attr_count; // has MethodParameters attribute
750 }
751 // Deprecated attribute would go here
752 if (access_flags.is_synthetic()) { // FIXME
753 // ++attr_count;
754 }
755 if (generic_signature_index != 0) {
756 ++attr_count;
757 }
758 if (anno != nullptr) {
759 ++attr_count; // has RuntimeVisibleAnnotations attribute
760 }
761 if (param_anno != nullptr) {
762 ++attr_count; // has RuntimeVisibleParameterAnnotations attribute
763 }
764 if (type_anno != nullptr) {
765 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
766 }
767
768 write_u2(checked_cast<u2>(attr_count));
769 if (const_method->code_size() > 0) {
770 write_code_attribute(method);
771 }
772 if (const_method->has_checked_exceptions()) {
773 write_exceptions_attribute(const_method);
774 }
775 if (default_anno != nullptr) {
776 write_annotations_attribute("AnnotationDefault", default_anno);
777 }
778 if (const_method->has_method_parameters()) {
779 write_method_parameter_attribute(const_method);
780 }
781 // Deprecated attribute would go here
782 if (access_flags.is_synthetic()) {
783 // write_synthetic_attribute();
784 }
785 if (generic_signature_index != 0) {
786 write_signature_attribute(generic_signature_index);
787 }
788 if (anno != nullptr) {
789 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
790 }
791 if (param_anno != nullptr) {
792 write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno);
793 }
794 if (type_anno != nullptr) {
795 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
796 }
797 }
798
799 // Write the class attributes portion of ClassFile structure
800 // JVMSpec| u2 attributes_count;
801 // JVMSpec| attribute_info attributes[attributes_count];
802 void JvmtiClassFileReconstituter::write_class_attributes() {
803 u2 inner_classes_length = inner_classes_attribute_length();
804 Symbol* generic_signature = ik()->generic_signature();
805 AnnotationArray* anno = ik()->class_annotations();
806 AnnotationArray* type_anno = ik()->class_type_annotations();
807
808 u2 attr_count = 0;
809 if (generic_signature != nullptr) {
810 ++attr_count;
811 }
812 if (ik()->source_file_name() != nullptr) {
813 ++attr_count;
814 }
815 if (ik()->source_debug_extension() != nullptr) {
816 ++attr_count;
817 }
818 if (inner_classes_length > 0) {
819 ++attr_count;
820 }
821 if (anno != nullptr) {
822 ++attr_count; // has RuntimeVisibleAnnotations attribute
823 }
824 if (type_anno != nullptr) {
825 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
826 }
827 if (cpool()->operands() != nullptr) {
828 ++attr_count;
829 }
830 if (ik()->nest_host_index() != 0) {
831 ++attr_count;
832 }
833 if (ik()->nest_members() != Universe::the_empty_short_array()) {
834 ++attr_count;
835 }
836 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) {
837 ++attr_count;
838 }
839 if (ik()->loadable_descriptors() != Universe::the_empty_short_array()) {
840 ++attr_count;
841 }
842 if (ik()->record_components() != nullptr) {
843 ++attr_count;
844 }
845
846 write_u2(attr_count);
847
848 if (generic_signature != nullptr) {
849 write_signature_attribute(symbol_to_cpool_index(generic_signature));
850 }
851 if (ik()->source_file_name() != nullptr) {
852 write_source_file_attribute();
853 }
854 if (ik()->source_debug_extension() != nullptr) {
855 write_source_debug_extension_attribute();
856 }
857 if (anno != nullptr) {
858 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
859 }
860 if (type_anno != nullptr) {
861 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
862 }
863 if (ik()->nest_host_index() != 0) {
864 write_nest_host_attribute();
865 }
866 if (ik()->nest_members() != Universe::the_empty_short_array()) {
867 write_nest_members_attribute();
868 }
869 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) {
870 write_permitted_subclasses_attribute();
871 }
872 if (ik()->loadable_descriptors() != Universe::the_empty_short_array()) {
873 write_loadable_descriptors_attribute();
874 }
875 if (ik()->record_components() != nullptr) {
876 write_record_attribute();
877 }
878 if (cpool()->operands() != nullptr) {
879 write_bootstrapmethod_attribute();
880 }
881 if (inner_classes_length > 0) {
882 write_inner_classes_attribute(inner_classes_length);
883 }
884 }
885
886 // Write the method information portion of ClassFile structure
887 // JVMSpec| u2 methods_count;
888 // JVMSpec| method_info methods[methods_count];
889 void JvmtiClassFileReconstituter::write_method_infos() {
890 HandleMark hm(thread());
891 Array<Method*>* methods = ik()->methods();
892 int num_methods = methods->length();
893 int num_overpass = 0;
894
895 // count the generated default interface methods
896 // these will not be re-created by write_method_info
897 // and should not be included in the total count
898 for (int index = 0; index < num_methods; index++) {
899 Method* method = methods->at(index);
900 if (method->is_overpass()) {
901 num_overpass++;
902 }
903 }
904
905 write_u2(checked_cast<u2>(num_methods - num_overpass));
906 if (JvmtiExport::can_maintain_original_method_order()) {
907 int index;
908 int original_index;
909 intArray method_order(num_methods, num_methods, 0);
910
911 // invert the method order mapping
912 for (index = 0; index < num_methods; index++) {
913 original_index = ik()->method_ordering()->at(index);
914 assert(original_index >= 0 && original_index < num_methods,
915 "invalid original method index");
916 method_order.at_put(original_index, index);
917 }
918
919 // write in original order
920 for (original_index = 0; original_index < num_methods; original_index++) {
921 index = method_order.at(original_index);
922 methodHandle method(thread(), methods->at(index));
923 write_method_info(method);
924 }
925 } else {
926 // method order not preserved just dump the method infos
927 for (int index = 0; index < num_methods; index++) {
928 methodHandle method(thread(), methods->at(index));
929 write_method_info(method);
930 }
931 }
932 }
933
934 void JvmtiClassFileReconstituter::write_class_file_format() {
935 ReallocMark();
936
937 // JVMSpec| ClassFile {
938 // JVMSpec| u4 magic;
939 write_u4(0xCAFEBABE);
940
941 // JVMSpec| u2 minor_version;
942 // JVMSpec| u2 major_version;
943 write_u2(ik()->minor_version());
944 u2 major = ik()->major_version();
945 write_u2(major);
946
947 // JVMSpec| u2 constant_pool_count;
948 // JVMSpec| cp_info constant_pool[constant_pool_count-1];
949 write_u2(checked_cast<u2>(cpool()->length()));
950 copy_cpool_bytes(writeable_address(cpool_size()));
951
952 // JVMSpec| u2 access_flags;
953 write_u2(ik()->access_flags().as_class_flags());
954
955 // JVMSpec| u2 this_class;
956 // JVMSpec| u2 super_class;
957 write_u2(class_symbol_to_cpool_index(ik()->name()));
958 Klass* super_class = ik()->super();
959 write_u2(super_class == nullptr? 0 : // zero for java.lang.Object
960 class_symbol_to_cpool_index(super_class->name()));
961
962 // JVMSpec| u2 interfaces_count;
963 // JVMSpec| u2 interfaces[interfaces_count];
964 Array<InstanceKlass*>* interfaces = ik()->local_interfaces();
965 int num_interfaces = interfaces->length();
966 write_u2(checked_cast<u2>(num_interfaces));
967 for (int index = 0; index < num_interfaces; index++) {
968 HandleMark hm(thread());
969 InstanceKlass* iik = interfaces->at(index);
970 write_u2(class_symbol_to_cpool_index(iik->name()));
971 }
972
973 // JVMSpec| u2 fields_count;
974 // JVMSpec| field_info fields[fields_count];
975 write_field_infos();
976
977 // JVMSpec| u2 methods_count;
978 // JVMSpec| method_info methods[methods_count];
979 write_method_infos();
980
981 // JVMSpec| u2 attributes_count;
982 // JVMSpec| attribute_info attributes[attributes_count];
983 // JVMSpec| } /* end ClassFile 8?
984 write_class_attributes();
985 }
986
987 address JvmtiClassFileReconstituter::writeable_address(size_t size) {
988 size_t used_size = _buffer_ptr - _buffer;
989 if (size + used_size >= _buffer_size) {
990 // compute the new buffer size: must be at least twice as big as before
991 // plus whatever new is being used; then convert to nice clean block boundary
992 size_t new_buffer_size = (size + _buffer_size*2 + 1) / initial_buffer_size
993 * initial_buffer_size;
994
995 // VM goes belly-up if the memory isn't available, so cannot do OOM processing
996 _buffer = REALLOC_RESOURCE_ARRAY(u1, _buffer, _buffer_size, new_buffer_size);
997 _buffer_size = new_buffer_size;
998 _buffer_ptr = _buffer + used_size;
999 }
1000 u1* ret_ptr = _buffer_ptr;
1001 _buffer_ptr += size;
1002 return ret_ptr;
1003 }
1004
1005 void JvmtiClassFileReconstituter::write_attribute_name_index(const char* name) {
1006 TempNewSymbol sym = SymbolTable::probe(name, (int)strlen(name));
1007 assert(sym != nullptr, "attribute name symbol not found");
1008 u2 attr_name_index = symbol_to_cpool_index(sym);
1009 assert(attr_name_index != 0, "attribute name symbol not in constant pool");
1010 write_u2(attr_name_index);
1011 }
1012
1013 void JvmtiClassFileReconstituter::write_u1(u1 x) {
1014 *writeable_address(1) = x;
1015 }
1016
1017 void JvmtiClassFileReconstituter::write_u2(u2 x) {
1018 Bytes::put_Java_u2(writeable_address(2), x);
1019 }
1020
1021 void JvmtiClassFileReconstituter::write_u4(u4 x) {
1022 Bytes::put_Java_u4(writeable_address(4), x);
1023 }
1024
1025 void JvmtiClassFileReconstituter::write_u8(u8 x) {
1026 Bytes::put_Java_u8(writeable_address(8), x);
1027 }
1028
1029 void JvmtiClassFileReconstituter::copy_bytecodes(const methodHandle& mh,
1030 unsigned char* bytecodes) {
1031 // We must copy bytecodes only from linked classes.
1032 // Being linked guarantees we are not getting bytecodes at
1033 // the same time the linking process is rewriting them.
1034 guarantee(mh->method_holder()->is_linked(), "Bytecodes must be copied from a linked class");
1035
1036 // use a BytecodeStream to iterate over the bytecodes. JVM/fast bytecodes
1037 // and the breakpoint bytecode are converted to their original bytecodes.
1038
1039 BytecodeStream bs(mh);
1040
1041 unsigned char* p = bytecodes;
1042 Bytecodes::Code code;
1043 bool is_rewritten = mh->method_holder()->is_rewritten();
1044
1045 while ((code = bs.next()) >= 0) {
1046 assert(Bytecodes::is_java_code(code), "sanity check");
1047 assert(code != Bytecodes::_breakpoint, "sanity check");
1048
1049 // length of bytecode (mnemonic + operands)
1050 address bcp = bs.bcp();
1051 int len = bs.instruction_size();
1052 assert(len > 0, "length must be > 0");
1053
1054 // copy the bytecodes
1055 *p = (unsigned char) (bs.is_wide()? Bytecodes::_wide : code);
1056 if (len > 1) {
1057 memcpy(p+1, bcp+1, len-1);
1058 }
1059
1060 // During linking the get/put and invoke instructions are rewritten
1061 // with an index into the constant pool cache. The original constant
1062 // pool index must be returned to caller. Rewrite the index.
1063 if (is_rewritten && len > 1) {
1064 bool is_wide = false;
1065 switch (code) {
1066 case Bytecodes::_getstatic : // fall through
1067 case Bytecodes::_putstatic : // fall through
1068 case Bytecodes::_getfield : // fall through
1069 case Bytecodes::_putfield : {
1070 int field_index = Bytes::get_native_u2(bcp+1);
1071 u2 pool_index = mh->constants()->resolved_field_entry_at(field_index)->constant_pool_index();
1072 assert(pool_index < mh->constants()->length(), "sanity check");
1073 Bytes::put_Java_u2((address)(p+1), pool_index); // java byte ordering
1074 break;
1075 }
1076 case Bytecodes::_invokevirtual : // fall through
1077 case Bytecodes::_invokespecial : // fall through
1078 case Bytecodes::_invokestatic : // fall through
1079 case Bytecodes::_invokedynamic : // fall through
1080 case Bytecodes::_invokeinterface : {
1081 assert(len == 3 ||
1082 (code == Bytecodes::_invokeinterface && len == 5) ||
1083 (code == Bytecodes::_invokedynamic && len == 5),
1084 "sanity check");
1085
1086 int cpci = Bytes::get_native_u2(bcp+1);
1087 bool is_invokedynamic = (code == Bytecodes::_invokedynamic);
1088 int pool_index;
1089 if (is_invokedynamic) {
1090 cpci = Bytes::get_native_u4(bcp+1);
1091 pool_index = mh->constants()->resolved_indy_entry_at(cpci)->constant_pool_index();
1092 } else {
1093 // cache cannot be pre-fetched since some classes won't have it yet
1094 pool_index = mh->constants()->resolved_method_entry_at(cpci)->constant_pool_index();
1095 }
1096 assert(pool_index < mh->constants()->length(), "sanity check");
1097 Bytes::put_Java_u2((address)(p+1), (u2)pool_index); // java byte ordering
1098 if (is_invokedynamic) *(p+3) = *(p+4) = 0;
1099 break;
1100 }
1101 case Bytecodes::_ldc_w:
1102 is_wide = true; // fall through
1103 case Bytecodes::_ldc: {
1104 if (bs.raw_code() == Bytecodes::_fast_aldc || bs.raw_code() == Bytecodes::_fast_aldc_w) {
1105 int cpci = is_wide ? Bytes::get_native_u2(bcp+1) : (u1)(*(bcp+1));
1106 int i = mh->constants()->object_to_cp_index(cpci);
1107 assert(i < mh->constants()->length(), "sanity check");
1108 if (is_wide) {
1109 Bytes::put_Java_u2((address)(p+1), (u2)i); // java byte ordering
1110 } else {
1111 *(p+1) = (u1)i;
1112 }
1113 }
1114 break;
1115 }
1116 default:
1117 break;
1118 }
1119 }
1120
1121 p += len;
1122 }
1123 }