1 /*
2 * Copyright (c) 2005, 2024, 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 "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.get_flags() & JVM_RECOGNIZED_FIELD_MODIFIERS);
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()->operand_argument_count_at(n);
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 u2 bootstrap_method_ref = cpool()->operand_bootstrap_method_ref_index_at(n);
411 u2 num_bootstrap_arguments = cpool()->operand_argument_count_at(n);
412 write_u2(bootstrap_method_ref);
413 write_u2(num_bootstrap_arguments);
414 for (int arg = 0; arg < num_bootstrap_arguments; arg++) {
415 u2 bootstrap_argument = cpool()->operand_argument_index_at(n, 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 // Record {
476 // u2 attribute_name_index;
477 // u4 attribute_length;
478 // u2 components_count;
479 // component_info components[components_count];
480 // }
481 // component_info {
482 // u2 name_index;
483 // u2 descriptor_index
484 // u2 attributes_count;
485 // attribute_info_attributes[attributes_count];
486 // }
487 void JvmtiClassFileReconstituter::write_record_attribute() {
488 Array<RecordComponent*>* components = ik()->record_components();
489 int number_of_components = components->length();
490
491 // Each component has a u2 for name, descr, attribute count
492 u4 length = checked_cast<u4>(sizeof(u2) + (sizeof(u2) * 3 * number_of_components));
493 for (int x = 0; x < number_of_components; x++) {
494 RecordComponent* component = components->at(x);
495 if (component->generic_signature_index() != 0) {
496 length += 8; // Signature attribute size
497 }
498 if (component->annotations() != nullptr) {
499 length += 6 + component->annotations()->length();
500 }
501 if (component->type_annotations() != nullptr) {
502 length += 6 + component->type_annotations()->length();
503 }
504 }
505
506 write_attribute_name_index("Record");
507 write_u4(length);
508 write_u2(checked_cast<u2>(number_of_components));
509 for (int i = 0; i < number_of_components; i++) {
510 RecordComponent* component = components->at(i);
511 write_u2(component->name_index());
512 write_u2(component->descriptor_index());
513 u2 attributes_count = (component->generic_signature_index() != 0 ? 1 : 0)
514 + (component->annotations() != nullptr ? 1 : 0)
515 + (component->type_annotations() != nullptr ? 1 : 0);
516
517 write_u2(attributes_count);
518 if (component->generic_signature_index() != 0) {
519 write_signature_attribute(component->generic_signature_index());
520 }
521 if (component->annotations() != nullptr) {
522 write_annotations_attribute("RuntimeVisibleAnnotations", component->annotations());
523 }
524 if (component->type_annotations() != nullptr) {
525 write_annotations_attribute("RuntimeVisibleTypeAnnotations", component->type_annotations());
526 }
527 }
528 }
529
530 // Write InnerClasses attribute
531 // JVMSpec| InnerClasses_attribute {
532 // JVMSpec| u2 attribute_name_index;
533 // JVMSpec| u4 attribute_length;
534 // JVMSpec| u2 number_of_classes;
535 // JVMSpec| { u2 inner_class_info_index;
536 // JVMSpec| u2 outer_class_info_index;
537 // JVMSpec| u2 inner_name_index;
538 // JVMSpec| u2 inner_class_access_flags;
539 // JVMSpec| } classes[number_of_classes];
540 // JVMSpec| }
541 void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {
542 InnerClassesIterator iter(ik());
543 guarantee(iter.length() != 0 && iter.length() == length,
544 "caller must check");
545 u2 entry_count = checked_cast<u2>(length / InstanceKlass::inner_class_next_offset);
546 u4 size = 2 + entry_count * (2+2+2+2);
547
548 write_attribute_name_index("InnerClasses");
549 write_u4(size);
550 write_u2(entry_count);
551 for (; !iter.done(); iter.next()) {
552 write_u2(iter.inner_class_info_index());
553 write_u2(iter.outer_class_info_index());
554 write_u2(iter.inner_name_index());
555 write_u2(iter.inner_access_flags());
556 }
557 }
558
559 // Write Synthetic attribute
560 // JVMSpec| Synthetic_attribute {
561 // JVMSpec| u2 attribute_name_index;
562 // JVMSpec| u4 attribute_length;
563 // JVMSpec| }
564 void JvmtiClassFileReconstituter::write_synthetic_attribute() {
565 write_attribute_name_index("Synthetic");
566 write_u4(0); //length always zero
567 }
568
569 // Compute size of LineNumberTable
570 u2 JvmtiClassFileReconstituter::line_number_table_entries(const methodHandle& method) {
571 // The line number table is compressed so we don't know how big it is until decompressed.
572 // Decompression is really fast so we just do it twice.
573 u2 num_entries = 0;
574 CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
575 while (stream.read_pair()) {
576 num_entries++;
577 }
578 return num_entries;
579 }
580
581 // Write LineNumberTable attribute
582 // JVMSpec| LineNumberTable_attribute {
583 // JVMSpec| u2 attribute_name_index;
584 // JVMSpec| u4 attribute_length;
585 // JVMSpec| u2 line_number_table_length;
586 // JVMSpec| { u2 start_pc;
587 // JVMSpec| u2 line_number;
588 // JVMSpec| } line_number_table[line_number_table_length];
589 // JVMSpec| }
590 void JvmtiClassFileReconstituter::write_line_number_table_attribute(const methodHandle& method,
591 u2 num_entries) {
592
593 write_attribute_name_index("LineNumberTable");
594 write_u4(2 + num_entries * (2 + 2));
595 write_u2(num_entries);
596
597 CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
598 while (stream.read_pair()) {
599 write_u2(checked_cast<u2>(stream.bci()));
600 write_u2(checked_cast<u2>(stream.line()));
601 }
602 }
603
604 // Write LocalVariableTable attribute
605 // JVMSpec| LocalVariableTable_attribute {
606 // JVMSpec| u2 attribute_name_index;
607 // JVMSpec| u4 attribute_length;
608 // JVMSpec| u2 local_variable_table_length;
609 // JVMSpec| { u2 start_pc;
610 // JVMSpec| u2 length;
611 // JVMSpec| u2 name_index;
612 // JVMSpec| u2 descriptor_index;
613 // JVMSpec| u2 index;
614 // JVMSpec| } local_variable_table[local_variable_table_length];
615 // JVMSpec| }
616 void JvmtiClassFileReconstituter::write_local_variable_table_attribute(const methodHandle& method, u2 num_entries) {
617 write_attribute_name_index("LocalVariableTable");
618 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
619 write_u2(num_entries);
620
621 assert(method->localvariable_table_length() == num_entries, "just checking");
622
623 LocalVariableTableElement *elem = method->localvariable_table_start();
624 for (int j=0; j<method->localvariable_table_length(); j++) {
625 write_u2(elem->start_bci);
626 write_u2(elem->length);
627 write_u2(elem->name_cp_index);
628 write_u2(elem->descriptor_cp_index);
629 write_u2(elem->slot);
630 elem++;
631 }
632 }
633
634 // Write LocalVariableTypeTable attribute
635 // JVMSpec| LocalVariableTypeTable_attribute {
636 // JVMSpec| u2 attribute_name_index;
637 // JVMSpec| u4 attribute_length;
638 // JVMSpec| u2 local_variable_type_table_length;
639 // JVMSpec| { u2 start_pc;
640 // JVMSpec| u2 length;
641 // JVMSpec| u2 name_index;
642 // JVMSpec| u2 signature_index;
643 // JVMSpec| u2 index;
644 // JVMSpec| } local_variable_type_table[local_variable_type_table_length];
645 // JVMSpec| }
646 void JvmtiClassFileReconstituter::write_local_variable_type_table_attribute(const methodHandle& method, u2 num_entries) {
647 write_attribute_name_index("LocalVariableTypeTable");
648 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2));
649 write_u2(num_entries);
650
651 LocalVariableTableElement *elem = method->localvariable_table_start();
652 for (int j=0; j<method->localvariable_table_length(); j++) {
653 if (elem->signature_cp_index > 0) {
654 // Local variable has a generic signature - write LVTT attribute entry
655 write_u2(elem->start_bci);
656 write_u2(elem->length);
657 write_u2(elem->name_cp_index);
658 write_u2(elem->signature_cp_index);
659 write_u2(elem->slot);
660 num_entries--;
661 }
662 elem++;
663 }
664 assert(num_entries == 0, "just checking");
665 }
666
667 // Write stack map table attribute
668 // JSR-202| StackMapTable_attribute {
669 // JSR-202| u2 attribute_name_index;
670 // JSR-202| u4 attribute_length;
671 // JSR-202| u2 number_of_entries;
672 // JSR-202| stack_map_frame_entries[number_of_entries];
673 // JSR-202| }
674 void JvmtiClassFileReconstituter::write_stackmap_table_attribute(const methodHandle& method,
675 int stackmap_len) {
676
677 write_attribute_name_index("StackMapTable");
678 write_u4(stackmap_len);
679 memcpy(
680 writeable_address(stackmap_len),
681 (void*)(method->stackmap_data()->adr_at(0)),
682 stackmap_len);
683 }
684
685 // Write one method_info structure
686 // JVMSpec| method_info {
687 // JVMSpec| u2 access_flags;
688 // JVMSpec| u2 name_index;
689 // JVMSpec| u2 descriptor_index;
690 // JVMSpec| u2 attributes_count;
691 // JVMSpec| attribute_info attributes[attributes_count];
692 // JVMSpec| }
693 void JvmtiClassFileReconstituter::write_method_info(const methodHandle& method) {
694 AccessFlags access_flags = method->access_flags();
695 ConstMethod* const_method = method->constMethod();
696 u2 generic_signature_index = const_method->generic_signature_index();
697 AnnotationArray* anno = method->annotations();
698 AnnotationArray* param_anno = method->parameter_annotations();
699 AnnotationArray* default_anno = method->annotation_default();
700 AnnotationArray* type_anno = method->type_annotations();
701
702 // skip generated default interface methods
703 if (method->is_overpass()) {
704 return;
705 }
706
707 write_u2(access_flags.get_flags() & JVM_RECOGNIZED_METHOD_MODIFIERS);
708 write_u2(const_method->name_index());
709 write_u2(const_method->signature_index());
710
711 // write attributes in the same order javac does, so we can test with byte for
712 // byte comparison
713 int attr_count = 0;
714 if (const_method->code_size() != 0) {
715 ++attr_count; // has Code attribute
716 }
717 if (const_method->has_checked_exceptions()) {
718 ++attr_count; // has Exceptions attribute
719 }
720 if (default_anno != nullptr) {
721 ++attr_count; // has AnnotationDefault attribute
722 }
723 if (const_method->has_method_parameters()) {
724 ++attr_count; // has MethodParameters attribute
725 }
726 // Deprecated attribute would go here
727 if (access_flags.is_synthetic()) { // FIXME
728 // ++attr_count;
729 }
730 if (generic_signature_index != 0) {
731 ++attr_count;
732 }
733 if (anno != nullptr) {
734 ++attr_count; // has RuntimeVisibleAnnotations attribute
735 }
736 if (param_anno != nullptr) {
737 ++attr_count; // has RuntimeVisibleParameterAnnotations attribute
738 }
739 if (type_anno != nullptr) {
740 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
741 }
742
743 write_u2(checked_cast<u2>(attr_count));
744 if (const_method->code_size() > 0) {
745 write_code_attribute(method);
746 }
747 if (const_method->has_checked_exceptions()) {
748 write_exceptions_attribute(const_method);
749 }
750 if (default_anno != nullptr) {
751 write_annotations_attribute("AnnotationDefault", default_anno);
752 }
753 if (const_method->has_method_parameters()) {
754 write_method_parameter_attribute(const_method);
755 }
756 // Deprecated attribute would go here
757 if (access_flags.is_synthetic()) {
758 // write_synthetic_attribute();
759 }
760 if (generic_signature_index != 0) {
761 write_signature_attribute(generic_signature_index);
762 }
763 if (anno != nullptr) {
764 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
765 }
766 if (param_anno != nullptr) {
767 write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno);
768 }
769 if (type_anno != nullptr) {
770 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
771 }
772 }
773
774 // Write the class attributes portion of ClassFile structure
775 // JVMSpec| u2 attributes_count;
776 // JVMSpec| attribute_info attributes[attributes_count];
777 void JvmtiClassFileReconstituter::write_class_attributes() {
778 u2 inner_classes_length = inner_classes_attribute_length();
779 Symbol* generic_signature = ik()->generic_signature();
780 AnnotationArray* anno = ik()->class_annotations();
781 AnnotationArray* type_anno = ik()->class_type_annotations();
782
783 u2 attr_count = 0;
784 if (generic_signature != nullptr) {
785 ++attr_count;
786 }
787 if (ik()->source_file_name() != nullptr) {
788 ++attr_count;
789 }
790 if (ik()->source_debug_extension() != nullptr) {
791 ++attr_count;
792 }
793 if (inner_classes_length > 0) {
794 ++attr_count;
795 }
796 if (anno != nullptr) {
797 ++attr_count; // has RuntimeVisibleAnnotations attribute
798 }
799 if (type_anno != nullptr) {
800 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute
801 }
802 if (cpool()->operands() != nullptr) {
803 ++attr_count;
804 }
805 if (ik()->nest_host_index() != 0) {
806 ++attr_count;
807 }
808 if (ik()->nest_members() != Universe::the_empty_short_array()) {
809 ++attr_count;
810 }
811 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) {
812 ++attr_count;
813 }
814 if (ik()->record_components() != nullptr) {
815 ++attr_count;
816 }
817
818 write_u2(attr_count);
819
820 if (generic_signature != nullptr) {
821 write_signature_attribute(symbol_to_cpool_index(generic_signature));
822 }
823 if (ik()->source_file_name() != nullptr) {
824 write_source_file_attribute();
825 }
826 if (ik()->source_debug_extension() != nullptr) {
827 write_source_debug_extension_attribute();
828 }
829 if (anno != nullptr) {
830 write_annotations_attribute("RuntimeVisibleAnnotations", anno);
831 }
832 if (type_anno != nullptr) {
833 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno);
834 }
835 if (ik()->nest_host_index() != 0) {
836 write_nest_host_attribute();
837 }
838 if (ik()->nest_members() != Universe::the_empty_short_array()) {
839 write_nest_members_attribute();
840 }
841 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) {
842 write_permitted_subclasses_attribute();
843 }
844 if (ik()->record_components() != nullptr) {
845 write_record_attribute();
846 }
847 if (cpool()->operands() != nullptr) {
848 write_bootstrapmethod_attribute();
849 }
850 if (inner_classes_length > 0) {
851 write_inner_classes_attribute(inner_classes_length);
852 }
853 }
854
855 // Write the method information portion of ClassFile structure
856 // JVMSpec| u2 methods_count;
857 // JVMSpec| method_info methods[methods_count];
858 void JvmtiClassFileReconstituter::write_method_infos() {
859 HandleMark hm(thread());
860 Array<Method*>* methods = ik()->methods();
861 int num_methods = methods->length();
862 int num_overpass = 0;
863
864 // count the generated default interface methods
865 // these will not be re-created by write_method_info
866 // and should not be included in the total count
867 for (int index = 0; index < num_methods; index++) {
868 Method* method = methods->at(index);
869 if (method->is_overpass()) {
870 num_overpass++;
871 }
872 }
873
874 write_u2(checked_cast<u2>(num_methods - num_overpass));
875 if (JvmtiExport::can_maintain_original_method_order()) {
876 int index;
877 int original_index;
878 intArray method_order(num_methods, num_methods, 0);
879
880 // invert the method order mapping
881 for (index = 0; index < num_methods; index++) {
882 original_index = ik()->method_ordering()->at(index);
883 assert(original_index >= 0 && original_index < num_methods,
884 "invalid original method index");
885 method_order.at_put(original_index, index);
886 }
887
888 // write in original order
889 for (original_index = 0; original_index < num_methods; original_index++) {
890 index = method_order.at(original_index);
891 methodHandle method(thread(), methods->at(index));
892 write_method_info(method);
893 }
894 } else {
895 // method order not preserved just dump the method infos
896 for (int index = 0; index < num_methods; index++) {
897 methodHandle method(thread(), methods->at(index));
898 write_method_info(method);
899 }
900 }
901 }
902
903 void JvmtiClassFileReconstituter::write_class_file_format() {
904 ReallocMark();
905
906 // JVMSpec| ClassFile {
907 // JVMSpec| u4 magic;
908 write_u4(0xCAFEBABE);
909
910 // JVMSpec| u2 minor_version;
911 // JVMSpec| u2 major_version;
912 write_u2(ik()->minor_version());
913 u2 major = ik()->major_version();
914 write_u2(major);
915
916 // JVMSpec| u2 constant_pool_count;
917 // JVMSpec| cp_info constant_pool[constant_pool_count-1];
918 write_u2(checked_cast<u2>(cpool()->length()));
919 copy_cpool_bytes(writeable_address(cpool_size()));
920
921 // JVMSpec| u2 access_flags;
922 write_u2(ik()->access_flags().get_flags() & JVM_RECOGNIZED_CLASS_MODIFIERS);
923
924 // JVMSpec| u2 this_class;
925 // JVMSpec| u2 super_class;
926 write_u2(class_symbol_to_cpool_index(ik()->name()));
927 Klass* super_class = ik()->super();
928 write_u2(super_class == nullptr? 0 : // zero for java.lang.Object
929 class_symbol_to_cpool_index(super_class->name()));
930
931 // JVMSpec| u2 interfaces_count;
932 // JVMSpec| u2 interfaces[interfaces_count];
933 Array<InstanceKlass*>* interfaces = ik()->local_interfaces();
934 int num_interfaces = interfaces->length();
935 write_u2(checked_cast<u2>(num_interfaces));
936 for (int index = 0; index < num_interfaces; index++) {
937 HandleMark hm(thread());
938 InstanceKlass* iik = interfaces->at(index);
939 write_u2(class_symbol_to_cpool_index(iik->name()));
940 }
941
942 // JVMSpec| u2 fields_count;
943 // JVMSpec| field_info fields[fields_count];
944 write_field_infos();
945
946 // JVMSpec| u2 methods_count;
947 // JVMSpec| method_info methods[methods_count];
948 write_method_infos();
949
950 // JVMSpec| u2 attributes_count;
951 // JVMSpec| attribute_info attributes[attributes_count];
952 // JVMSpec| } /* end ClassFile 8?
953 write_class_attributes();
954 }
955
956 address JvmtiClassFileReconstituter::writeable_address(size_t size) {
957 size_t used_size = _buffer_ptr - _buffer;
958 if (size + used_size >= _buffer_size) {
959 // compute the new buffer size: must be at least twice as big as before
960 // plus whatever new is being used; then convert to nice clean block boundary
961 size_t new_buffer_size = (size + _buffer_size*2 + 1) / initial_buffer_size
962 * initial_buffer_size;
963
964 // VM goes belly-up if the memory isn't available, so cannot do OOM processing
965 _buffer = REALLOC_RESOURCE_ARRAY(u1, _buffer, _buffer_size, new_buffer_size);
966 _buffer_size = new_buffer_size;
967 _buffer_ptr = _buffer + used_size;
968 }
969 u1* ret_ptr = _buffer_ptr;
970 _buffer_ptr += size;
971 return ret_ptr;
972 }
973
974 void JvmtiClassFileReconstituter::write_attribute_name_index(const char* name) {
975 TempNewSymbol sym = SymbolTable::probe(name, (int)strlen(name));
976 assert(sym != nullptr, "attribute name symbol not found");
977 u2 attr_name_index = symbol_to_cpool_index(sym);
978 assert(attr_name_index != 0, "attribute name symbol not in constant pool");
979 write_u2(attr_name_index);
980 }
981
982 void JvmtiClassFileReconstituter::write_u1(u1 x) {
983 *writeable_address(1) = x;
984 }
985
986 void JvmtiClassFileReconstituter::write_u2(u2 x) {
987 Bytes::put_Java_u2(writeable_address(2), x);
988 }
989
990 void JvmtiClassFileReconstituter::write_u4(u4 x) {
991 Bytes::put_Java_u4(writeable_address(4), x);
992 }
993
994 void JvmtiClassFileReconstituter::write_u8(u8 x) {
995 Bytes::put_Java_u8(writeable_address(8), x);
996 }
997
998 void JvmtiClassFileReconstituter::copy_bytecodes(const methodHandle& mh,
999 unsigned char* bytecodes) {
1000 // use a BytecodeStream to iterate over the bytecodes. JVM/fast bytecodes
1001 // and the breakpoint bytecode are converted to their original bytecodes.
1002
1003 BytecodeStream bs(mh);
1004
1005 unsigned char* p = bytecodes;
1006 Bytecodes::Code code;
1007 bool is_rewritten = mh->method_holder()->is_rewritten();
1008
1009 while ((code = bs.next()) >= 0) {
1010 assert(Bytecodes::is_java_code(code), "sanity check");
1011 assert(code != Bytecodes::_breakpoint, "sanity check");
1012
1013 // length of bytecode (mnemonic + operands)
1014 address bcp = bs.bcp();
1015 int len = bs.instruction_size();
1016 assert(len > 0, "length must be > 0");
1017
1018 // copy the bytecodes
1019 *p = (unsigned char) (bs.is_wide()? Bytecodes::_wide : code);
1020 if (len > 1) {
1021 memcpy(p+1, bcp+1, len-1);
1022 }
1023
1024 // During linking the get/put and invoke instructions are rewritten
1025 // with an index into the constant pool cache. The original constant
1026 // pool index must be returned to caller. Rewrite the index.
1027 if (is_rewritten && len > 1) {
1028 bool is_wide = false;
1029 switch (code) {
1030 case Bytecodes::_getstatic : // fall through
1031 case Bytecodes::_putstatic : // fall through
1032 case Bytecodes::_getfield : // fall through
1033 case Bytecodes::_putfield : {
1034 int field_index = Bytes::get_native_u2(bcp+1);
1035 u2 pool_index = mh->constants()->resolved_field_entry_at(field_index)->constant_pool_index();
1036 assert(pool_index < mh->constants()->length(), "sanity check");
1037 Bytes::put_Java_u2((address)(p+1), pool_index); // java byte ordering
1038 break;
1039 }
1040 case Bytecodes::_invokevirtual : // fall through
1041 case Bytecodes::_invokespecial : // fall through
1042 case Bytecodes::_invokestatic : // fall through
1043 case Bytecodes::_invokedynamic : // fall through
1044 case Bytecodes::_invokeinterface : {
1045 assert(len == 3 ||
1046 (code == Bytecodes::_invokeinterface && len == 5) ||
1047 (code == Bytecodes::_invokedynamic && len == 5),
1048 "sanity check");
1049
1050 int cpci = Bytes::get_native_u2(bcp+1);
1051 bool is_invokedynamic = (code == Bytecodes::_invokedynamic);
1052 int pool_index;
1053 if (is_invokedynamic) {
1054 cpci = Bytes::get_native_u4(bcp+1);
1055 pool_index = mh->constants()->resolved_indy_entry_at(cpci)->constant_pool_index();
1056 } else {
1057 // cache cannot be pre-fetched since some classes won't have it yet
1058 pool_index = mh->constants()->resolved_method_entry_at(cpci)->constant_pool_index();
1059 }
1060 assert(pool_index < mh->constants()->length(), "sanity check");
1061 Bytes::put_Java_u2((address)(p+1), (u2)pool_index); // java byte ordering
1062 if (is_invokedynamic) *(p+3) = *(p+4) = 0;
1063 break;
1064 }
1065 case Bytecodes::_ldc_w:
1066 is_wide = true; // fall through
1067 case Bytecodes::_ldc: {
1068 if (bs.raw_code() == Bytecodes::_fast_aldc || bs.raw_code() == Bytecodes::_fast_aldc_w) {
1069 int cpci = is_wide ? Bytes::get_native_u2(bcp+1) : (u1)(*(bcp+1));
1070 int i = mh->constants()->object_to_cp_index(cpci);
1071 assert(i < mh->constants()->length(), "sanity check");
1072 if (is_wide) {
1073 Bytes::put_Java_u2((address)(p+1), (u2)i); // java byte ordering
1074 } else {
1075 *(p+1) = (u1)i;
1076 }
1077 }
1078 break;
1079 }
1080 default:
1081 break;
1082 }
1083 }
1084
1085 p += len;
1086 }
1087 }