1 /*
2 * Copyright (c) 2005, 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 #include "precompiled.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/vmClasses.hpp"
28 #include "interpreter/bytecodeStream.hpp"
29 #include "memory/universe.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.get_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 Array<u2>* operands = cpool()->operands();
395 write_attribute_name_index("BootstrapMethods");
396 int num_bootstrap_methods = ConstantPool::operand_array_length(operands);
397
398 // calculate length of attribute
399 u4 length = sizeof(u2); // num_bootstrap_methods
400 for (int n = 0; n < num_bootstrap_methods; n++) {
401 u2 num_bootstrap_arguments = cpool()->operand_argument_count_at(n);
402 length += sizeof(u2); // bootstrap_method_ref
403 length += sizeof(u2); // num_bootstrap_arguments
404 length += (u4)sizeof(u2) * num_bootstrap_arguments; // bootstrap_arguments[num_bootstrap_arguments]
405 }
406 write_u4(length);
407
408 // write attribute
409 write_u2(checked_cast<u2>(num_bootstrap_methods));
410 for (int n = 0; n < num_bootstrap_methods; n++) {
411 u2 bootstrap_method_ref = cpool()->operand_bootstrap_method_ref_index_at(n);
412 u2 num_bootstrap_arguments = cpool()->operand_argument_count_at(n);
413 write_u2(bootstrap_method_ref);
414 write_u2(num_bootstrap_arguments);
415 for (int arg = 0; arg < num_bootstrap_arguments; arg++) {
416 u2 bootstrap_argument = cpool()->operand_argument_index_at(n, arg);
417 write_u2(bootstrap_argument);
418 }
419 }
420 }
421
422 // NestHost_attribute {
423 // u2 attribute_name_index;
424 // u4 attribute_length;
425 // u2 host_class_index;
426 // }
427 void JvmtiClassFileReconstituter::write_nest_host_attribute() {
428 int length = sizeof(u2);
429 u2 host_class_index = ik()->nest_host_index();
430
431 write_attribute_name_index("NestHost");
432 write_u4(length);
433 write_u2(host_class_index);
434 }
435
436 // NestMembers_attribute {
437 // u2 attribute_name_index;
438 // u4 attribute_length;
439 // u2 number_of_classes;
440 // u2 classes[number_of_classes];
441 // }
442 void JvmtiClassFileReconstituter::write_nest_members_attribute() {
443 Array<u2>* nest_members = ik()->nest_members();
444 int number_of_classes = nest_members->length();
445 int length = sizeof(u2) * (1 + number_of_classes);
446
447 write_attribute_name_index("NestMembers");
448 write_u4(length);
449 write_u2(checked_cast<u2>(number_of_classes));
450 for (int i = 0; i < number_of_classes; i++) {
451 u2 class_cp_index = nest_members->at(i);
452 write_u2(class_cp_index);
453 }
454 }
455
456 // PermittedSubclasses {
457 // u2 attribute_name_index;
458 // u4 attribute_length;
459 // u2 number_of_classes;
460 // u2 classes[number_of_classes];
461 // }
462 void JvmtiClassFileReconstituter::write_permitted_subclasses_attribute() {
463 Array<u2>* permitted_subclasses = ik()->permitted_subclasses();
464 int number_of_classes = permitted_subclasses->length();
465 int length = sizeof(u2) * (1 + number_of_classes); // '1 +' is for number_of_classes field
466
467 write_attribute_name_index("PermittedSubclasses");
468 write_u4(length);
469 write_u2(checked_cast<u2>(number_of_classes));
470 for (int i = 0; i < number_of_classes; i++) {
471 u2 class_cp_index = permitted_subclasses->at(i);
472 write_u2(class_cp_index);
473 }
474 }
475
476 // Record {
477 // u2 attribute_name_index;
478 // u4 attribute_length;
479 // u2 components_count;
480 // component_info components[components_count];
481 // }
482 // component_info {
483 // u2 name_index;
484 // u2 descriptor_index
485 // u2 attributes_count;
486 // attribute_info_attributes[attributes_count];
487 // }
488 void JvmtiClassFileReconstituter::write_record_attribute() {
489 Array<RecordComponent*>* components = ik()->record_components();
490 int number_of_components = components->length();
491
492 // Each component has a u2 for name, descr, attribute count
493 u4 length = checked_cast<u4>(sizeof(u2) + (sizeof(u2) * 3 * number_of_components));
494 for (int x = 0; x < number_of_components; x++) {
495 RecordComponent* component = components->at(x);
496 if (component->generic_signature_index() != 0) {
497 length += 8; // Signature attribute size
498 assert(component->attributes_count() > 0, "Bad component attributes count");
499 }
500 if (component->annotations() != nullptr) {
501 length += 6 + component->annotations()->length();
502 }
503 if (component->type_annotations() != nullptr) {
504 length += 6 + component->type_annotations()->length();
505 }
506 }
507
508 write_attribute_name_index("Record");
509 write_u4(length);
510 write_u2(checked_cast<u2>(number_of_components));
511 for (int i = 0; i < number_of_components; i++) {
512 RecordComponent* component = components->at(i);
513 write_u2(component->name_index());
514 write_u2(component->descriptor_index());
515 write_u2(component->attributes_count());
516 if (component->generic_signature_index() != 0) {
517 write_signature_attribute(component->generic_signature_index());
518 }
519 if (component->annotations() != nullptr) {
520 write_annotations_attribute("RuntimeVisibleAnnotations", component->annotations());
521 }
522 if (component->type_annotations() != nullptr) {
523 write_annotations_attribute("RuntimeVisibleTypeAnnotations", component->type_annotations());
524 }
525 }
526 }
527
528 // Write InnerClasses attribute
529 // JVMSpec| InnerClasses_attribute {
530 // JVMSpec| u2 attribute_name_index;
531 // JVMSpec| u4 attribute_length;
532 // JVMSpec| u2 number_of_classes;
533 // JVMSpec| { u2 inner_class_info_index;
534 // JVMSpec| u2 outer_class_info_index;
535 // JVMSpec| u2 inner_name_index;
536 // JVMSpec| u2 inner_class_access_flags;
537 // JVMSpec| } classes[number_of_classes];
538 // JVMSpec| }
539 void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {
540 InnerClassesIterator iter(ik());
541 guarantee(iter.length() != 0 && iter.length() == length,
542 "caller must check");
543 u2 entry_count = checked_cast<u2>(length / InstanceKlass::inner_class_next_offset);
544 u4 size = 2 + entry_count * (2+2+2+2);
545
546 write_attribute_name_index("InnerClasses");
547 write_u4(size);
548 write_u2(entry_count);
549 for (; !iter.done(); iter.next()) {
550 write_u2(iter.inner_class_info_index());
551 write_u2(iter.outer_class_info_index());
552 write_u2(iter.inner_name_index());
553 write_u2(iter.inner_access_flags());
554 }
555 }
556
557 // Write Synthetic attribute
558 // JVMSpec| Synthetic_attribute {
559 // JVMSpec| u2 attribute_name_index;
560 // JVMSpec| u4 attribute_length;
561 // JVMSpec| }
562 void JvmtiClassFileReconstituter::write_synthetic_attribute() {
563 write_attribute_name_index("Synthetic");
564 write_u4(0); //length always zero
565 }
566
567 // Compute size of LineNumberTable
568 u2 JvmtiClassFileReconstituter::line_number_table_entries(const methodHandle& method) {
569 // The line number table is compressed so we don't know how big it is until decompressed.
570 // Decompression is really fast so we just do it twice.
571 u2 num_entries = 0;
572 CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
573 while (stream.read_pair()) {
574 num_entries++;
575 }
576 return num_entries;
577 }
578
579 // Write LineNumberTable attribute
580 // JVMSpec| LineNumberTable_attribute {
581 // JVMSpec| u2 attribute_name_index;
582 // JVMSpec| u4 attribute_length;
583 // JVMSpec| u2 line_number_table_length;
584 // JVMSpec| { u2 start_pc;
585 // JVMSpec| u2 line_number;
586 // JVMSpec| } line_number_table[line_number_table_length];
587 // JVMSpec| }
588 void JvmtiClassFileReconstituter::write_line_number_table_attribute(const methodHandle& method,
589 u2 num_entries) {
590
591 write_attribute_name_index("LineNumberTable");
592 write_u4(2 + num_entries * (2 + 2));
593 write_u2(num_entries);
594
595 CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
596 while (stream.read_pair()) {
597 write_u2(checked_cast<u2>(stream.bci()));
598 write_u2(checked_cast<u2>(stream.line()));
599 }
600 }
601
602 // Write LocalVariableTable attribute
603 // JVMSpec| LocalVariableTable_attribute {
604 // JVMSpec| u2 attribute_name_index;
605 // JVMSpec| u4 attribute_length;
606 // JVMSpec| u2 local_variable_table_length;
607 // JVMSpec| { u2 start_pc;
608 // JVMSpec| u2 length;
609 // JVMSpec| u2 name_index;
610 // JVMSpec| u2 descriptor_index;
611 // JVMSpec| u2 index;
612 // JVMSpec| } local_variable_table[local_variable_table_length];
613 // JVMSpec| }
614 void JvmtiClassFileReconstituter::write_local_variable_table_attribute(const methodHandle& method, u2 num_entries) {
615 write_attribute_name_index("LocalVariableTable");
616 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
617 write_u2(num_entries);
618
619 assert(method->localvariable_table_length() == num_entries, "just checking");
620
621 LocalVariableTableElement *elem = method->localvariable_table_start();
622 for (int j=0; j<method->localvariable_table_length(); j++) {
623 write_u2(elem->start_bci);
624 write_u2(elem->length);
625 write_u2(elem->name_cp_index);
626 write_u2(elem->descriptor_cp_index);
627 write_u2(elem->slot);
628 elem++;
629 }
630 }
631
632 // Write LocalVariableTypeTable attribute
633 // JVMSpec| LocalVariableTypeTable_attribute {
634 // JVMSpec| u2 attribute_name_index;
635 // JVMSpec| u4 attribute_length;
636 // JVMSpec| u2 local_variable_type_table_length;
637 // JVMSpec| { u2 start_pc;
638 // JVMSpec| u2 length;
639 // JVMSpec| u2 name_index;
640 // JVMSpec| u2 signature_index;
641 // JVMSpec| u2 index;
642 // JVMSpec| } local_variable_type_table[local_variable_type_table_length];
643 // JVMSpec| }
644 void JvmtiClassFileReconstituter::write_local_variable_type_table_attribute(const methodHandle& method, u2 num_entries) {
645 write_attribute_name_index("LocalVariableTypeTable");
646 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
647 write_u2(num_entries);
648
649 LocalVariableTableElement *elem = method->localvariable_table_start();
650 for (int j=0; j<method->localvariable_table_length(); j++) {
651 if (elem->signature_cp_index > 0) {
652 // Local variable has a generic signature - write LVTT attribute entry
653 write_u2(elem->start_bci);
654 write_u2(elem->length);
655 write_u2(elem->name_cp_index);
656 write_u2(elem->signature_cp_index);
657 write_u2(elem->slot);
658 num_entries--;
659 }
660 elem++;
661 }
662 assert(num_entries == 0, "just checking");
663 }
664
665 // Write stack map table attribute
666 // JSR-202| StackMapTable_attribute {
667 // JSR-202| u2 attribute_name_index;
668 // JSR-202| u4 attribute_length;
669 // JSR-202| u2 number_of_entries;
670 // JSR-202| stack_map_frame_entries[number_of_entries];
671 // JSR-202| }
672 void JvmtiClassFileReconstituter::write_stackmap_table_attribute(const methodHandle& method,
673 int stackmap_len) {
674
675 write_attribute_name_index("StackMapTable");
676 write_u4(stackmap_len);
677 memcpy(
678 writeable_address(stackmap_len),
679 (void*)(method->stackmap_data()->adr_at(0)),
680 stackmap_len);
681 }
682
683 // Write one method_info structure
684 // JVMSpec| method_info {
685 // JVMSpec| u2 access_flags;
686 // JVMSpec| u2 name_index;
687 // JVMSpec| u2 descriptor_index;
688 // JVMSpec| u2 attributes_count;
689 // JVMSpec| attribute_info attributes[attributes_count];
690 // JVMSpec| }
691 void JvmtiClassFileReconstituter::write_method_info(const methodHandle& method) {
692 AccessFlags access_flags = method->access_flags();
693 ConstMethod* const_method = method->constMethod();
694 u2 generic_signature_index = const_method->generic_signature_index();
695 AnnotationArray* anno = method->annotations();
696 AnnotationArray* param_anno = method->parameter_annotations();
697 AnnotationArray* default_anno = method->annotation_default();
698 AnnotationArray* type_anno = method->type_annotations();
699
700 // skip generated default interface methods
701 if (method->is_overpass()) {
702 return;
703 }
704
705 write_u2(access_flags.get_flags() & JVM_RECOGNIZED_METHOD_MODIFIERS);
706 write_u2(const_method->name_index());
707 write_u2(const_method->signature_index());
708
709 // write attributes in the same order javac does, so we can test with byte for
710 // byte comparison
711 int attr_count = 0;
712 if (const_method->code_size() != 0) {
713 ++attr_count; // has Code attribute
714 }
715 if (const_method->has_checked_exceptions()) {
716 ++attr_count; // has Exceptions attribute
717 }
718 if (default_anno != nullptr) {
719 ++attr_count; // has AnnotationDefault attribute
720 }
721 if (const_method->has_method_parameters()) {
722 ++attr_count; // has MethodParameters attribute
723 }
724 // Deprecated attribute would go here
725 if (access_flags.is_synthetic()) { // FIXME
726 // ++attr_count;
727 }
728 if (generic_signature_index != 0) {
729 ++attr_count;
730 }
731 if (anno != nullptr) {
732 ++attr_count; // has RuntimeVisibleAnnotations attribute
733 }
734 if (param_anno != nullptr) {
735 ++attr_count; // has RuntimeVisibleParameterAnnotations attribute
736 }
737 if (type_anno != nullptr) {
738 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
739 }
740
741 write_u2(checked_cast<u2>(attr_count));
742 if (const_method->code_size() > 0) {
743 write_code_attribute(method);
744 }
745 if (const_method->has_checked_exceptions()) {
746 write_exceptions_attribute(const_method);
747 }
748 if (default_anno != nullptr) {
749 write_annotations_attribute("AnnotationDefault", default_anno);
750 }
751 if (const_method->has_method_parameters()) {
752 write_method_parameter_attribute(const_method);
753 }
754 // Deprecated attribute would go here
755 if (access_flags.is_synthetic()) {
756 // write_synthetic_attribute();
757 }
758 if (generic_signature_index != 0) {
759 write_signature_attribute(generic_signature_index);
760 }
761 if (anno != nullptr) {
762 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
763 }
764 if (param_anno != nullptr) {
765 write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno);
766 }
767 if (type_anno != nullptr) {
768 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
769 }
770 }
771
772 // Write the class attributes portion of ClassFile structure
773 // JVMSpec| u2 attributes_count;
774 // JVMSpec| attribute_info attributes[attributes_count];
775 void JvmtiClassFileReconstituter::write_class_attributes() {
776 u2 inner_classes_length = inner_classes_attribute_length();
777 Symbol* generic_signature = ik()->generic_signature();
778 AnnotationArray* anno = ik()->class_annotations();
779 AnnotationArray* type_anno = ik()->class_type_annotations();
780
781 u2 attr_count = 0;
782 if (generic_signature != nullptr) {
783 ++attr_count;
784 }
785 if (ik()->source_file_name() != nullptr) {
786 ++attr_count;
787 }
788 if (ik()->source_debug_extension() != nullptr) {
789 ++attr_count;
790 }
791 if (inner_classes_length > 0) {
792 ++attr_count;
793 }
794 if (anno != nullptr) {
795 ++attr_count; // has RuntimeVisibleAnnotations attribute
796 }
797 if (type_anno != nullptr) {
798 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
799 }
800 if (cpool()->operands() != nullptr) {
801 ++attr_count;
802 }
803 if (ik()->nest_host_index() != 0) {
804 ++attr_count;
805 }
806 if (ik()->nest_members() != Universe::the_empty_short_array()) {
807 ++attr_count;
808 }
809 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) {
810 ++attr_count;
811 }
812 if (ik()->record_components() != nullptr) {
813 ++attr_count;
814 }
815
816 write_u2(attr_count);
817
818 if (generic_signature != nullptr) {
819 write_signature_attribute(symbol_to_cpool_index(generic_signature));
820 }
821 if (ik()->source_file_name() != nullptr) {
822 write_source_file_attribute();
823 }
824 if (ik()->source_debug_extension() != nullptr) {
825 write_source_debug_extension_attribute();
826 }
827 if (anno != nullptr) {
828 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
829 }
830 if (type_anno != nullptr) {
831 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
832 }
833 if (ik()->nest_host_index() != 0) {
834 write_nest_host_attribute();
835 }
836 if (ik()->nest_members() != Universe::the_empty_short_array()) {
837 write_nest_members_attribute();
838 }
839 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) {
840 write_permitted_subclasses_attribute();
841 }
842 if (ik()->record_components() != nullptr) {
843 write_record_attribute();
844 }
845 if (cpool()->operands() != nullptr) {
846 write_bootstrapmethod_attribute();
847 }
848 if (inner_classes_length > 0) {
849 write_inner_classes_attribute(inner_classes_length);
850 }
851 }
852
853 // Write the method information portion of ClassFile structure
854 // JVMSpec| u2 methods_count;
855 // JVMSpec| method_info methods[methods_count];
856 void JvmtiClassFileReconstituter::write_method_infos() {
857 HandleMark hm(thread());
858 Array<Method*>* methods = ik()->methods();
859 int num_methods = methods->length();
860 int num_overpass = 0;
861
862 // count the generated default interface methods
863 // these will not be re-created by write_method_info
864 // and should not be included in the total count
865 for (int index = 0; index < num_methods; index++) {
866 Method* method = methods->at(index);
867 if (method->is_overpass()) {
868 num_overpass++;
869 }
870 }
871
872 write_u2(checked_cast<u2>(num_methods - num_overpass));
873 if (JvmtiExport::can_maintain_original_method_order()) {
874 int index;
875 int original_index;
876 intArray method_order(num_methods, num_methods, 0);
877
878 // invert the method order mapping
879 for (index = 0; index < num_methods; index++) {
880 original_index = ik()->method_ordering()->at(index);
881 assert(original_index >= 0 && original_index < num_methods,
882 "invalid original method index");
883 method_order.at_put(original_index, index);
884 }
885
886 // write in original order
887 for (original_index = 0; original_index < num_methods; original_index++) {
888 index = method_order.at(original_index);
889 methodHandle method(thread(), methods->at(index));
890 write_method_info(method);
891 }
892 } else {
893 // method order not preserved just dump the method infos
894 for (int index = 0; index < num_methods; index++) {
895 methodHandle method(thread(), methods->at(index));
896 write_method_info(method);
897 }
898 }
899 }
900
901 void JvmtiClassFileReconstituter::write_class_file_format() {
902 ReallocMark();
903
904 // JVMSpec| ClassFile {
905 // JVMSpec| u4 magic;
906 write_u4(0xCAFEBABE);
907
908 // JVMSpec| u2 minor_version;
909 // JVMSpec| u2 major_version;
910 write_u2(ik()->minor_version());
911 u2 major = ik()->major_version();
912 write_u2(major);
913
914 // JVMSpec| u2 constant_pool_count;
915 // JVMSpec| cp_info constant_pool[constant_pool_count-1];
916 write_u2(checked_cast<u2>(cpool()->length()));
917 copy_cpool_bytes(writeable_address(cpool_size()));
918
919 // JVMSpec| u2 access_flags;
920 write_u2(ik()->access_flags().get_flags() & (JVM_RECOGNIZED_CLASS_MODIFIERS));
921 // JVMSpec| u2 this_class;
922 // JVMSpec| u2 super_class;
923 write_u2(class_symbol_to_cpool_index(ik()->name()));
924 Klass* super_class = ik()->super();
925 write_u2(super_class == nullptr? 0 : // zero for java.lang.Object
926 class_symbol_to_cpool_index(super_class->name()));
927
928 // JVMSpec| u2 interfaces_count;
929 // JVMSpec| u2 interfaces[interfaces_count];
930 Array<InstanceKlass*>* interfaces = ik()->local_interfaces();
931 int num_interfaces = interfaces->length();
932 write_u2(checked_cast<u2>(num_interfaces));
933 for (int index = 0; index < num_interfaces; index++) {
934 HandleMark hm(thread());
935 InstanceKlass* iik = interfaces->at(index);
936 write_u2(class_symbol_to_cpool_index(iik->name()));
937 }
938
939 // JVMSpec| u2 fields_count;
940 // JVMSpec| field_info fields[fields_count];
941 write_field_infos();
942
943 // JVMSpec| u2 methods_count;
944 // JVMSpec| method_info methods[methods_count];
945 write_method_infos();
946
947 // JVMSpec| u2 attributes_count;
948 // JVMSpec| attribute_info attributes[attributes_count];
949 // JVMSpec| } /* end ClassFile 8?
950 write_class_attributes();
951 }
952
953 address JvmtiClassFileReconstituter::writeable_address(size_t size) {
954 size_t used_size = _buffer_ptr - _buffer;
955 if (size + used_size >= _buffer_size) {
956 // compute the new buffer size: must be at least twice as big as before
957 // plus whatever new is being used; then convert to nice clean block boundary
958 size_t new_buffer_size = (size + _buffer_size*2 + 1) / initial_buffer_size
959 * initial_buffer_size;
960
961 // VM goes belly-up if the memory isn't available, so cannot do OOM processing
962 _buffer = REALLOC_RESOURCE_ARRAY(u1, _buffer, _buffer_size, new_buffer_size);
963 _buffer_size = new_buffer_size;
964 _buffer_ptr = _buffer + used_size;
965 }
966 u1* ret_ptr = _buffer_ptr;
967 _buffer_ptr += size;
968 return ret_ptr;
969 }
970
971 void JvmtiClassFileReconstituter::write_attribute_name_index(const char* name) {
972 TempNewSymbol sym = SymbolTable::probe(name, (int)strlen(name));
973 assert(sym != nullptr, "attribute name symbol not found");
974 u2 attr_name_index = symbol_to_cpool_index(sym);
975 assert(attr_name_index != 0, "attribute name symbol not in constant pool");
976 write_u2(attr_name_index);
977 }
978
979 void JvmtiClassFileReconstituter::write_u1(u1 x) {
980 *writeable_address(1) = x;
981 }
982
983 void JvmtiClassFileReconstituter::write_u2(u2 x) {
984 Bytes::put_Java_u2(writeable_address(2), x);
985 }
986
987 void JvmtiClassFileReconstituter::write_u4(u4 x) {
988 Bytes::put_Java_u4(writeable_address(4), x);
989 }
990
991 void JvmtiClassFileReconstituter::write_u8(u8 x) {
992 Bytes::put_Java_u8(writeable_address(8), x);
993 }
994
995 void JvmtiClassFileReconstituter::copy_bytecodes(const methodHandle& mh,
996 unsigned char* bytecodes) {
997 // use a BytecodeStream to iterate over the bytecodes. JVM/fast bytecodes
998 // and the breakpoint bytecode are converted to their original bytecodes.
999
1000 BytecodeStream bs(mh);
1001
1002 unsigned char* p = bytecodes;
1003 Bytecodes::Code code;
1004 bool is_rewritten = mh->method_holder()->is_rewritten();
1005
1006 while ((code = bs.next()) >= 0) {
1007 assert(Bytecodes::is_java_code(code), "sanity check");
1008 assert(code != Bytecodes::_breakpoint, "sanity check");
1009
1010 // length of bytecode (mnemonic + operands)
1011 address bcp = bs.bcp();
1012 int len = bs.instruction_size();
1013 assert(len > 0, "length must be > 0");
1014
1015 // copy the bytecodes
1016 *p = (unsigned char) (bs.is_wide()? Bytecodes::_wide : code);
1017 if (len > 1) {
1018 memcpy(p+1, bcp+1, len-1);
1019 }
1020
1021 // During linking the get/put and invoke instructions are rewritten
1022 // with an index into the constant pool cache. The original constant
1023 // pool index must be returned to caller. Rewrite the index.
1024 if (is_rewritten && len > 1) {
1025 bool is_wide = false;
1026 switch (code) {
1027 case Bytecodes::_getstatic : // fall through
1028 case Bytecodes::_putstatic : // fall through
1029 case Bytecodes::_getfield : // fall through
1030 case Bytecodes::_putfield : {
1031 int field_index = Bytes::get_native_u2(bcp+1);
1032 u2 pool_index = mh->constants()->resolved_field_entry_at(field_index)->constant_pool_index();
1033 assert(pool_index < mh->constants()->length(), "sanity check");
1034 Bytes::put_Java_u2((address)(p+1), pool_index); // java byte ordering
1035 break;
1036 }
1037 case Bytecodes::_invokevirtual : // fall through
1038 case Bytecodes::_invokespecial : // fall through
1039 case Bytecodes::_invokestatic : // fall through
1040 case Bytecodes::_invokedynamic : // fall through
1041 case Bytecodes::_invokeinterface : {
1042 assert(len == 3 ||
1043 (code == Bytecodes::_invokeinterface && len == 5) ||
1044 (code == Bytecodes::_invokedynamic && len == 5),
1045 "sanity check");
1046
1047 int cpci = Bytes::get_native_u2(bcp+1);
1048 bool is_invokedynamic = (code == Bytecodes::_invokedynamic);
1049 int pool_index;
1050 if (is_invokedynamic) {
1051 cpci = Bytes::get_native_u4(bcp+1);
1052 pool_index = mh->constants()->resolved_indy_entry_at(mh->constants()->decode_invokedynamic_index(cpci))->constant_pool_index();
1053 } else {
1054 // cache cannot be pre-fetched since some classes won't have it yet
1055 pool_index = mh->constants()->resolved_method_entry_at(cpci)->constant_pool_index();
1056 }
1057 assert(pool_index < mh->constants()->length(), "sanity check");
1058 Bytes::put_Java_u2((address)(p+1), (u2)pool_index); // java byte ordering
1059 if (is_invokedynamic) *(p+3) = *(p+4) = 0;
1060 break;
1061 }
1062 case Bytecodes::_ldc_w:
1063 is_wide = true; // fall through
1064 case Bytecodes::_ldc: {
1065 if (bs.raw_code() == Bytecodes::_fast_aldc || bs.raw_code() == Bytecodes::_fast_aldc_w) {
1066 int cpci = is_wide ? Bytes::get_native_u2(bcp+1) : (u1)(*(bcp+1));
1067 int i = mh->constants()->object_to_cp_index(cpci);
1068 assert(i < mh->constants()->length(), "sanity check");
1069 if (is_wide) {
1070 Bytes::put_Java_u2((address)(p+1), (u2)i); // java byte ordering
1071 } else {
1072 *(p+1) = (u1)i;
1073 }
1074 }
1075 break;
1076 }
1077 default:
1078 break;
1079 }
1080 }
1081
1082 p += len;
1083 }
1084 }