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()->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 // 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 write_u2(iter.inner_access_flags()); 576 } 577 } 578 579 // Write Synthetic attribute 580 // JVMSpec| Synthetic_attribute { 581 // JVMSpec| u2 attribute_name_index; 582 // JVMSpec| u4 attribute_length; 583 // JVMSpec| } 584 void JvmtiClassFileReconstituter::write_synthetic_attribute() { 585 write_attribute_name_index("Synthetic"); 586 write_u4(0); //length always zero 587 } 588 589 // Compute size of LineNumberTable 590 u2 JvmtiClassFileReconstituter::line_number_table_entries(const methodHandle& method) { 591 // The line number table is compressed so we don't know how big it is until decompressed. 592 // Decompression is really fast so we just do it twice. 593 u2 num_entries = 0; 594 CompressedLineNumberReadStream stream(method->compressed_linenumber_table()); 595 while (stream.read_pair()) { 596 num_entries++; 597 } 598 return num_entries; 599 } 600 601 // Write LineNumberTable attribute 602 // JVMSpec| LineNumberTable_attribute { 603 // JVMSpec| u2 attribute_name_index; 604 // JVMSpec| u4 attribute_length; 605 // JVMSpec| u2 line_number_table_length; 606 // JVMSpec| { u2 start_pc; 607 // JVMSpec| u2 line_number; 608 // JVMSpec| } line_number_table[line_number_table_length]; 609 // JVMSpec| } 610 void JvmtiClassFileReconstituter::write_line_number_table_attribute(const methodHandle& method, 611 u2 num_entries) { 612 613 write_attribute_name_index("LineNumberTable"); 614 write_u4(2 + num_entries * (2 + 2)); 615 write_u2(num_entries); 616 617 CompressedLineNumberReadStream stream(method->compressed_linenumber_table()); 618 while (stream.read_pair()) { 619 write_u2(checked_cast<u2>(stream.bci())); 620 write_u2(checked_cast<u2>(stream.line())); 621 } 622 } 623 624 // Write LocalVariableTable attribute 625 // JVMSpec| LocalVariableTable_attribute { 626 // JVMSpec| u2 attribute_name_index; 627 // JVMSpec| u4 attribute_length; 628 // JVMSpec| u2 local_variable_table_length; 629 // JVMSpec| { u2 start_pc; 630 // JVMSpec| u2 length; 631 // JVMSpec| u2 name_index; 632 // JVMSpec| u2 descriptor_index; 633 // JVMSpec| u2 index; 634 // JVMSpec| } local_variable_table[local_variable_table_length]; 635 // JVMSpec| } 636 void JvmtiClassFileReconstituter::write_local_variable_table_attribute(const methodHandle& method, u2 num_entries) { 637 write_attribute_name_index("LocalVariableTable"); 638 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2)); 639 write_u2(num_entries); 640 641 assert(method->localvariable_table_length() == num_entries, "just checking"); 642 643 LocalVariableTableElement *elem = method->localvariable_table_start(); 644 for (int j=0; j<method->localvariable_table_length(); j++) { 645 write_u2(elem->start_bci); 646 write_u2(elem->length); 647 write_u2(elem->name_cp_index); 648 write_u2(elem->descriptor_cp_index); 649 write_u2(elem->slot); 650 elem++; 651 } 652 } 653 654 // Write LocalVariableTypeTable attribute 655 // JVMSpec| LocalVariableTypeTable_attribute { 656 // JVMSpec| u2 attribute_name_index; 657 // JVMSpec| u4 attribute_length; 658 // JVMSpec| u2 local_variable_type_table_length; 659 // JVMSpec| { u2 start_pc; 660 // JVMSpec| u2 length; 661 // JVMSpec| u2 name_index; 662 // JVMSpec| u2 signature_index; 663 // JVMSpec| u2 index; 664 // JVMSpec| } local_variable_type_table[local_variable_type_table_length]; 665 // JVMSpec| } 666 void JvmtiClassFileReconstituter::write_local_variable_type_table_attribute(const methodHandle& method, u2 num_entries) { 667 write_attribute_name_index("LocalVariableTypeTable"); 668 write_u4(2 + num_entries * (2 + 2 + 2 + 2 + 2)); 669 write_u2(num_entries); 670 671 LocalVariableTableElement *elem = method->localvariable_table_start(); 672 for (int j=0; j<method->localvariable_table_length(); j++) { 673 if (elem->signature_cp_index > 0) { 674 // Local variable has a generic signature - write LVTT attribute entry 675 write_u2(elem->start_bci); 676 write_u2(elem->length); 677 write_u2(elem->name_cp_index); 678 write_u2(elem->signature_cp_index); 679 write_u2(elem->slot); 680 num_entries--; 681 } 682 elem++; 683 } 684 assert(num_entries == 0, "just checking"); 685 } 686 687 // Write stack map table attribute 688 // JSR-202| StackMapTable_attribute { 689 // JSR-202| u2 attribute_name_index; 690 // JSR-202| u4 attribute_length; 691 // JSR-202| u2 number_of_entries; 692 // JSR-202| stack_map_frame_entries[number_of_entries]; 693 // JSR-202| } 694 void JvmtiClassFileReconstituter::write_stackmap_table_attribute(const methodHandle& method, 695 int stackmap_len) { 696 697 write_attribute_name_index("StackMapTable"); 698 write_u4(stackmap_len); 699 memcpy( 700 writeable_address(stackmap_len), 701 (void*)(method->stackmap_data()->adr_at(0)), 702 stackmap_len); 703 } 704 705 // Write one method_info structure 706 // JVMSpec| method_info { 707 // JVMSpec| u2 access_flags; 708 // JVMSpec| u2 name_index; 709 // JVMSpec| u2 descriptor_index; 710 // JVMSpec| u2 attributes_count; 711 // JVMSpec| attribute_info attributes[attributes_count]; 712 // JVMSpec| } 713 void JvmtiClassFileReconstituter::write_method_info(const methodHandle& method) { 714 AccessFlags access_flags = method->access_flags(); 715 ConstMethod* const_method = method->constMethod(); 716 u2 generic_signature_index = const_method->generic_signature_index(); 717 AnnotationArray* anno = method->annotations(); 718 AnnotationArray* param_anno = method->parameter_annotations(); 719 AnnotationArray* default_anno = method->annotation_default(); 720 AnnotationArray* type_anno = method->type_annotations(); 721 722 // skip generated default interface methods 723 if (method->is_overpass()) { 724 return; 725 } 726 727 write_u2(access_flags.as_method_flags()); 728 write_u2(const_method->name_index()); 729 write_u2(const_method->signature_index()); 730 731 // write attributes in the same order javac does, so we can test with byte for 732 // byte comparison 733 int attr_count = 0; 734 if (const_method->code_size() != 0) { 735 ++attr_count; // has Code attribute 736 } 737 if (const_method->has_checked_exceptions()) { 738 ++attr_count; // has Exceptions attribute 739 } 740 if (default_anno != nullptr) { 741 ++attr_count; // has AnnotationDefault attribute 742 } 743 if (const_method->has_method_parameters()) { 744 ++attr_count; // has MethodParameters attribute 745 } 746 // Deprecated attribute would go here 747 if (access_flags.is_synthetic()) { // FIXME 748 // ++attr_count; 749 } 750 if (generic_signature_index != 0) { 751 ++attr_count; 752 } 753 if (anno != nullptr) { 754 ++attr_count; // has RuntimeVisibleAnnotations attribute 755 } 756 if (param_anno != nullptr) { 757 ++attr_count; // has RuntimeVisibleParameterAnnotations attribute 758 } 759 if (type_anno != nullptr) { 760 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute 761 } 762 763 write_u2(checked_cast<u2>(attr_count)); 764 if (const_method->code_size() > 0) { 765 write_code_attribute(method); 766 } 767 if (const_method->has_checked_exceptions()) { 768 write_exceptions_attribute(const_method); 769 } 770 if (default_anno != nullptr) { 771 write_annotations_attribute("AnnotationDefault", default_anno); 772 } 773 if (const_method->has_method_parameters()) { 774 write_method_parameter_attribute(const_method); 775 } 776 // Deprecated attribute would go here 777 if (access_flags.is_synthetic()) { 778 // write_synthetic_attribute(); 779 } 780 if (generic_signature_index != 0) { 781 write_signature_attribute(generic_signature_index); 782 } 783 if (anno != nullptr) { 784 write_annotations_attribute("RuntimeVisibleAnnotations", anno); 785 } 786 if (param_anno != nullptr) { 787 write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno); 788 } 789 if (type_anno != nullptr) { 790 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno); 791 } 792 } 793 794 // Write the class attributes portion of ClassFile structure 795 // JVMSpec| u2 attributes_count; 796 // JVMSpec| attribute_info attributes[attributes_count]; 797 void JvmtiClassFileReconstituter::write_class_attributes() { 798 u2 inner_classes_length = inner_classes_attribute_length(); 799 Symbol* generic_signature = ik()->generic_signature(); 800 AnnotationArray* anno = ik()->class_annotations(); 801 AnnotationArray* type_anno = ik()->class_type_annotations(); 802 803 u2 attr_count = 0; 804 if (generic_signature != nullptr) { 805 ++attr_count; 806 } 807 if (ik()->source_file_name() != nullptr) { 808 ++attr_count; 809 } 810 if (ik()->source_debug_extension() != nullptr) { 811 ++attr_count; 812 } 813 if (inner_classes_length > 0) { 814 ++attr_count; 815 } 816 if (anno != nullptr) { 817 ++attr_count; // has RuntimeVisibleAnnotations attribute 818 } 819 if (type_anno != nullptr) { 820 ++attr_count; // has RuntimeVisibleTypeAnnotations attribute 821 } 822 if (cpool()->operands() != nullptr) { 823 ++attr_count; 824 } 825 if (ik()->nest_host_index() != 0) { 826 ++attr_count; 827 } 828 if (ik()->nest_members() != Universe::the_empty_short_array()) { 829 ++attr_count; 830 } 831 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) { 832 ++attr_count; 833 } 834 if (ik()->loadable_descriptors() != Universe::the_empty_short_array()) { 835 ++attr_count; 836 } 837 if (ik()->record_components() != nullptr) { 838 ++attr_count; 839 } 840 841 write_u2(attr_count); 842 843 if (generic_signature != nullptr) { 844 write_signature_attribute(symbol_to_cpool_index(generic_signature)); 845 } 846 if (ik()->source_file_name() != nullptr) { 847 write_source_file_attribute(); 848 } 849 if (ik()->source_debug_extension() != nullptr) { 850 write_source_debug_extension_attribute(); 851 } 852 if (anno != nullptr) { 853 write_annotations_attribute("RuntimeVisibleAnnotations", anno); 854 } 855 if (type_anno != nullptr) { 856 write_annotations_attribute("RuntimeVisibleTypeAnnotations", type_anno); 857 } 858 if (ik()->nest_host_index() != 0) { 859 write_nest_host_attribute(); 860 } 861 if (ik()->nest_members() != Universe::the_empty_short_array()) { 862 write_nest_members_attribute(); 863 } 864 if (ik()->permitted_subclasses() != Universe::the_empty_short_array()) { 865 write_permitted_subclasses_attribute(); 866 } 867 if (ik()->loadable_descriptors() != Universe::the_empty_short_array()) { 868 write_loadable_descriptors_attribute(); 869 } 870 if (ik()->record_components() != nullptr) { 871 write_record_attribute(); 872 } 873 if (cpool()->operands() != nullptr) { 874 write_bootstrapmethod_attribute(); 875 } 876 if (inner_classes_length > 0) { 877 write_inner_classes_attribute(inner_classes_length); 878 } 879 } 880 881 // Write the method information portion of ClassFile structure 882 // JVMSpec| u2 methods_count; 883 // JVMSpec| method_info methods[methods_count]; 884 void JvmtiClassFileReconstituter::write_method_infos() { 885 HandleMark hm(thread()); 886 Array<Method*>* methods = ik()->methods(); 887 int num_methods = methods->length(); 888 int num_overpass = 0; 889 890 // count the generated default interface methods 891 // these will not be re-created by write_method_info 892 // and should not be included in the total count 893 for (int index = 0; index < num_methods; index++) { 894 Method* method = methods->at(index); 895 if (method->is_overpass()) { 896 num_overpass++; 897 } 898 } 899 900 write_u2(checked_cast<u2>(num_methods - num_overpass)); 901 if (JvmtiExport::can_maintain_original_method_order()) { 902 int index; 903 int original_index; 904 intArray method_order(num_methods, num_methods, 0); 905 906 // invert the method order mapping 907 for (index = 0; index < num_methods; index++) { 908 original_index = ik()->method_ordering()->at(index); 909 assert(original_index >= 0 && original_index < num_methods, 910 "invalid original method index"); 911 method_order.at_put(original_index, index); 912 } 913 914 // write in original order 915 for (original_index = 0; original_index < num_methods; original_index++) { 916 index = method_order.at(original_index); 917 methodHandle method(thread(), methods->at(index)); 918 write_method_info(method); 919 } 920 } else { 921 // method order not preserved just dump the method infos 922 for (int index = 0; index < num_methods; index++) { 923 methodHandle method(thread(), methods->at(index)); 924 write_method_info(method); 925 } 926 } 927 } 928 929 void JvmtiClassFileReconstituter::write_class_file_format() { 930 ReallocMark(); 931 932 // JVMSpec| ClassFile { 933 // JVMSpec| u4 magic; 934 write_u4(0xCAFEBABE); 935 936 // JVMSpec| u2 minor_version; 937 // JVMSpec| u2 major_version; 938 write_u2(ik()->minor_version()); 939 u2 major = ik()->major_version(); 940 write_u2(major); 941 942 // JVMSpec| u2 constant_pool_count; 943 // JVMSpec| cp_info constant_pool[constant_pool_count-1]; 944 write_u2(checked_cast<u2>(cpool()->length())); 945 copy_cpool_bytes(writeable_address(cpool_size())); 946 947 // JVMSpec| u2 access_flags; 948 write_u2(ik()->access_flags().as_class_flags()); 949 950 // JVMSpec| u2 this_class; 951 // JVMSpec| u2 super_class; 952 write_u2(class_symbol_to_cpool_index(ik()->name())); 953 Klass* super_class = ik()->super(); 954 write_u2(super_class == nullptr? 0 : // zero for java.lang.Object 955 class_symbol_to_cpool_index(super_class->name())); 956 957 // JVMSpec| u2 interfaces_count; 958 // JVMSpec| u2 interfaces[interfaces_count]; 959 Array<InstanceKlass*>* interfaces = ik()->local_interfaces(); 960 int num_interfaces = interfaces->length(); 961 write_u2(checked_cast<u2>(num_interfaces)); 962 for (int index = 0; index < num_interfaces; index++) { 963 HandleMark hm(thread()); 964 InstanceKlass* iik = interfaces->at(index); 965 write_u2(class_symbol_to_cpool_index(iik->name())); 966 } 967 968 // JVMSpec| u2 fields_count; 969 // JVMSpec| field_info fields[fields_count]; 970 write_field_infos(); 971 972 // JVMSpec| u2 methods_count; 973 // JVMSpec| method_info methods[methods_count]; 974 write_method_infos(); 975 976 // JVMSpec| u2 attributes_count; 977 // JVMSpec| attribute_info attributes[attributes_count]; 978 // JVMSpec| } /* end ClassFile 8? 979 write_class_attributes(); 980 } 981 982 address JvmtiClassFileReconstituter::writeable_address(size_t size) { 983 size_t used_size = _buffer_ptr - _buffer; 984 if (size + used_size >= _buffer_size) { 985 // compute the new buffer size: must be at least twice as big as before 986 // plus whatever new is being used; then convert to nice clean block boundary 987 size_t new_buffer_size = (size + _buffer_size*2 + 1) / initial_buffer_size 988 * initial_buffer_size; 989 990 // VM goes belly-up if the memory isn't available, so cannot do OOM processing 991 _buffer = REALLOC_RESOURCE_ARRAY(u1, _buffer, _buffer_size, new_buffer_size); 992 _buffer_size = new_buffer_size; 993 _buffer_ptr = _buffer + used_size; 994 } 995 u1* ret_ptr = _buffer_ptr; 996 _buffer_ptr += size; 997 return ret_ptr; 998 } 999 1000 void JvmtiClassFileReconstituter::write_attribute_name_index(const char* name) { 1001 TempNewSymbol sym = SymbolTable::probe(name, (int)strlen(name)); 1002 assert(sym != nullptr, "attribute name symbol not found"); 1003 u2 attr_name_index = symbol_to_cpool_index(sym); 1004 assert(attr_name_index != 0, "attribute name symbol not in constant pool"); 1005 write_u2(attr_name_index); 1006 } 1007 1008 void JvmtiClassFileReconstituter::write_u1(u1 x) { 1009 *writeable_address(1) = x; 1010 } 1011 1012 void JvmtiClassFileReconstituter::write_u2(u2 x) { 1013 Bytes::put_Java_u2(writeable_address(2), x); 1014 } 1015 1016 void JvmtiClassFileReconstituter::write_u4(u4 x) { 1017 Bytes::put_Java_u4(writeable_address(4), x); 1018 } 1019 1020 void JvmtiClassFileReconstituter::write_u8(u8 x) { 1021 Bytes::put_Java_u8(writeable_address(8), x); 1022 } 1023 1024 void JvmtiClassFileReconstituter::copy_bytecodes(const methodHandle& mh, 1025 unsigned char* bytecodes) { 1026 // use a BytecodeStream to iterate over the bytecodes. JVM/fast bytecodes 1027 // and the breakpoint bytecode are converted to their original bytecodes. 1028 1029 BytecodeStream bs(mh); 1030 1031 unsigned char* p = bytecodes; 1032 Bytecodes::Code code; 1033 bool is_rewritten = mh->method_holder()->is_rewritten(); 1034 1035 while ((code = bs.next()) >= 0) { 1036 assert(Bytecodes::is_java_code(code), "sanity check"); 1037 assert(code != Bytecodes::_breakpoint, "sanity check"); 1038 1039 // length of bytecode (mnemonic + operands) 1040 address bcp = bs.bcp(); 1041 int len = bs.instruction_size(); 1042 assert(len > 0, "length must be > 0"); 1043 1044 // copy the bytecodes 1045 *p = (unsigned char) (bs.is_wide()? Bytecodes::_wide : code); 1046 if (len > 1) { 1047 memcpy(p+1, bcp+1, len-1); 1048 } 1049 1050 // During linking the get/put and invoke instructions are rewritten 1051 // with an index into the constant pool cache. The original constant 1052 // pool index must be returned to caller. Rewrite the index. 1053 if (is_rewritten && len > 1) { 1054 bool is_wide = false; 1055 switch (code) { 1056 case Bytecodes::_getstatic : // fall through 1057 case Bytecodes::_putstatic : // fall through 1058 case Bytecodes::_getfield : // fall through 1059 case Bytecodes::_putfield : { 1060 int field_index = Bytes::get_native_u2(bcp+1); 1061 u2 pool_index = mh->constants()->resolved_field_entry_at(field_index)->constant_pool_index(); 1062 assert(pool_index < mh->constants()->length(), "sanity check"); 1063 Bytes::put_Java_u2((address)(p+1), pool_index); // java byte ordering 1064 break; 1065 } 1066 case Bytecodes::_invokevirtual : // fall through 1067 case Bytecodes::_invokespecial : // fall through 1068 case Bytecodes::_invokestatic : // fall through 1069 case Bytecodes::_invokedynamic : // fall through 1070 case Bytecodes::_invokeinterface : { 1071 assert(len == 3 || 1072 (code == Bytecodes::_invokeinterface && len == 5) || 1073 (code == Bytecodes::_invokedynamic && len == 5), 1074 "sanity check"); 1075 1076 int cpci = Bytes::get_native_u2(bcp+1); 1077 bool is_invokedynamic = (code == Bytecodes::_invokedynamic); 1078 int pool_index; 1079 if (is_invokedynamic) { 1080 cpci = Bytes::get_native_u4(bcp+1); 1081 pool_index = mh->constants()->resolved_indy_entry_at(cpci)->constant_pool_index(); 1082 } else { 1083 // cache cannot be pre-fetched since some classes won't have it yet 1084 pool_index = mh->constants()->resolved_method_entry_at(cpci)->constant_pool_index(); 1085 } 1086 assert(pool_index < mh->constants()->length(), "sanity check"); 1087 Bytes::put_Java_u2((address)(p+1), (u2)pool_index); // java byte ordering 1088 if (is_invokedynamic) *(p+3) = *(p+4) = 0; 1089 break; 1090 } 1091 case Bytecodes::_ldc_w: 1092 is_wide = true; // fall through 1093 case Bytecodes::_ldc: { 1094 if (bs.raw_code() == Bytecodes::_fast_aldc || bs.raw_code() == Bytecodes::_fast_aldc_w) { 1095 int cpci = is_wide ? Bytes::get_native_u2(bcp+1) : (u1)(*(bcp+1)); 1096 int i = mh->constants()->object_to_cp_index(cpci); 1097 assert(i < mh->constants()->length(), "sanity check"); 1098 if (is_wide) { 1099 Bytes::put_Java_u2((address)(p+1), (u2)i); // java byte ordering 1100 } else { 1101 *(p+1) = (u1)i; 1102 } 1103 } 1104 break; 1105 } 1106 default: 1107 break; 1108 } 1109 } 1110 1111 p += len; 1112 } 1113 }