1 /* 2 * Copyright (c) 1998, 2018, 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 "gc/shared/gcLocker.hpp" 27 #include "interpreter/bytecodes.hpp" 28 #include "interpreter/interpreter.hpp" 29 #include "interpreter/rewriter.hpp" 30 #include "memory/metadataFactory.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "oops/generateOopMap.hpp" 33 #include "prims/methodHandles.hpp" 34 #include "runtime/handles.inline.hpp" 35 36 // Computes a CPC map (new_index -> original_index) for constant pool entries 37 // that are referred to by the interpreter at runtime via the constant pool cache. 38 // Also computes a CP map (original_index -> new_index). 39 // Marks entries in CP which require additional processing. 40 void Rewriter::compute_index_maps() { 41 const int length = _pool->length(); 42 init_maps(length); 43 bool saw_mh_symbol = false; 44 for (int i = 0; i < length; i++) { 45 int tag = _pool->tag_at(i).value(); 46 switch (tag) { 47 case JVM_CONSTANT_InterfaceMethodref: 48 case JVM_CONSTANT_Fieldref : // fall through 49 case JVM_CONSTANT_Methodref : // fall through 50 add_cp_cache_entry(i); 51 break; 52 case JVM_CONSTANT_Dynamic: 53 assert(_pool->has_dynamic_constant(), "constant pool's _has_dynamic_constant flag not set"); 54 add_resolved_references_entry(i); 55 break; 56 case JVM_CONSTANT_String : // fall through 57 case JVM_CONSTANT_MethodHandle : // fall through 58 case JVM_CONSTANT_MethodType : // fall through 59 add_resolved_references_entry(i); 60 break; 61 case JVM_CONSTANT_Utf8: 62 if (_pool->symbol_at(i) == vmSymbols::java_lang_invoke_MethodHandle() || 63 _pool->symbol_at(i) == vmSymbols::java_lang_invoke_VarHandle()) { 64 saw_mh_symbol = true; 65 } 66 break; 67 } 68 } 69 70 // Record limits of resolved reference map for constant pool cache indices 71 record_map_limits(); 72 73 guarantee((int) _cp_cache_map.length() - 1 <= (int) ((u2)-1), 74 "all cp cache indexes fit in a u2"); 75 76 if (saw_mh_symbol) { 77 _method_handle_invokers.at_grow(length, 0); 78 } 79 } 80 81 // Unrewrite the bytecodes if an error occurs. 82 void Rewriter::restore_bytecodes() { 83 int len = _methods->length(); 84 bool invokespecial_error = false; 85 86 for (int i = len-1; i >= 0; i--) { 87 Method* method = _methods->at(i); 88 scan_method(method, true, &invokespecial_error); 89 assert(!invokespecial_error, "reversing should not get an invokespecial error"); 90 } 91 } 92 93 // Creates a constant pool cache given a CPC map 94 void Rewriter::make_constant_pool_cache(TRAPS) { 95 ClassLoaderData* loader_data = _pool->pool_holder()->class_loader_data(); 96 ConstantPoolCache* cache = 97 ConstantPoolCache::allocate(loader_data, _cp_cache_map, 98 _invokedynamic_cp_cache_map, 99 _invokedynamic_references_map, CHECK); 100 101 // initialize object cache in constant pool 102 _pool->set_cache(cache); 103 cache->set_constant_pool(_pool()); 104 105 // _resolved_references is stored in pool->cache(), so need to be done after 106 // the above lines. 107 _pool->initialize_resolved_references(loader_data, _resolved_references_map, 108 _resolved_reference_limit, 109 THREAD); 110 111 // Clean up constant pool cache if initialize_resolved_references() failed. 112 if (HAS_PENDING_EXCEPTION) { 113 MetadataFactory::free_metadata(loader_data, cache); 114 _pool->set_cache(NULL); // so the verifier isn't confused 115 } else { 116 DEBUG_ONLY( 117 if (DumpSharedSpaces) { 118 cache->verify_just_initialized(); 119 }) 120 } 121 } 122 123 124 125 // The new finalization semantics says that registration of 126 // finalizable objects must be performed on successful return from the 127 // Object.<init> constructor. We could implement this trivially if 128 // <init> were never rewritten but since JVMTI allows this to occur, a 129 // more complicated solution is required. A special return bytecode 130 // is used only by Object.<init> to signal the finalization 131 // registration point. Additionally local 0 must be preserved so it's 132 // available to pass to the registration function. For simplicity we 133 // require that local 0 is never overwritten so it's available as an 134 // argument for registration. 135 136 void Rewriter::rewrite_Object_init(const methodHandle& method, TRAPS) { 137 RawBytecodeStream bcs(method); 138 while (!bcs.is_last_bytecode()) { 139 Bytecodes::Code opcode = bcs.raw_next(); 140 switch (opcode) { 141 case Bytecodes::_return: *bcs.bcp() = Bytecodes::_return_register_finalizer; break; 142 143 case Bytecodes::_istore: 144 case Bytecodes::_lstore: 145 case Bytecodes::_fstore: 146 case Bytecodes::_dstore: 147 case Bytecodes::_astore: 148 if (bcs.get_index() != 0) continue; 149 150 // fall through 151 case Bytecodes::_istore_0: 152 case Bytecodes::_lstore_0: 153 case Bytecodes::_fstore_0: 154 case Bytecodes::_dstore_0: 155 case Bytecodes::_astore_0: 156 THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), 157 "can't overwrite local 0 in Object.<init>"); 158 break; 159 160 default: 161 break; 162 } 163 } 164 } 165 166 167 // Rewrite a classfile-order CP index into a native-order CPC index. 168 void Rewriter::rewrite_member_reference(address bcp, int offset, bool reverse) { 169 address p = bcp + offset; 170 if (!reverse) { 171 int cp_index = Bytes::get_Java_u2(p); 172 int cache_index = cp_entry_to_cp_cache(cp_index); 173 Bytes::put_native_u2(p, cache_index); 174 if (!_method_handle_invokers.is_empty()) 175 maybe_rewrite_invokehandle(p - 1, cp_index, cache_index, reverse); 176 } else { 177 int cache_index = Bytes::get_native_u2(p); 178 int pool_index = cp_cache_entry_pool_index(cache_index); 179 Bytes::put_Java_u2(p, pool_index); 180 if (!_method_handle_invokers.is_empty()) 181 maybe_rewrite_invokehandle(p - 1, pool_index, cache_index, reverse); 182 } 183 } 184 185 // If the constant pool entry for invokespecial is InterfaceMethodref, 186 // we need to add a separate cpCache entry for its resolution, because it is 187 // different than the resolution for invokeinterface with InterfaceMethodref. 188 // These cannot share cpCache entries. 189 void Rewriter::rewrite_invokespecial(address bcp, int offset, bool reverse, bool* invokespecial_error) { 190 address p = bcp + offset; 191 if (!reverse) { 192 int cp_index = Bytes::get_Java_u2(p); 193 if (_pool->tag_at(cp_index).is_interface_method()) { 194 int cache_index = add_invokespecial_cp_cache_entry(cp_index); 195 if (cache_index != (int)(jushort) cache_index) { 196 *invokespecial_error = true; 197 } 198 Bytes::put_native_u2(p, cache_index); 199 } else { 200 rewrite_member_reference(bcp, offset, reverse); 201 } 202 } else { 203 rewrite_member_reference(bcp, offset, reverse); 204 } 205 } 206 207 208 // Adjust the invocation bytecode for a signature-polymorphic method (MethodHandle.invoke, etc.) 209 void Rewriter::maybe_rewrite_invokehandle(address opc, int cp_index, int cache_index, bool reverse) { 210 if (!reverse) { 211 if ((*opc) == (u1)Bytecodes::_invokevirtual || 212 // allow invokespecial as an alias, although it would be very odd: 213 (*opc) == (u1)Bytecodes::_invokespecial) { 214 assert(_pool->tag_at(cp_index).is_method(), "wrong index"); 215 // Determine whether this is a signature-polymorphic method. 216 if (cp_index >= _method_handle_invokers.length()) return; 217 int status = _method_handle_invokers.at(cp_index); 218 assert(status >= -1 && status <= 1, "oob tri-state"); 219 if (status == 0) { 220 if (_pool->klass_ref_at_noresolve(cp_index) == vmSymbols::java_lang_invoke_MethodHandle() && 221 MethodHandles::is_signature_polymorphic_name(SystemDictionary::MethodHandle_klass(), 222 _pool->name_ref_at(cp_index))) { 223 // we may need a resolved_refs entry for the appendix 224 add_invokedynamic_resolved_references_entries(cp_index, cache_index); 225 status = +1; 226 } else if (_pool->klass_ref_at_noresolve(cp_index) == vmSymbols::java_lang_invoke_VarHandle() && 227 MethodHandles::is_signature_polymorphic_name(SystemDictionary::VarHandle_klass(), 228 _pool->name_ref_at(cp_index))) { 229 // we may need a resolved_refs entry for the appendix 230 add_invokedynamic_resolved_references_entries(cp_index, cache_index); 231 status = +1; 232 } else { 233 status = -1; 234 } 235 _method_handle_invokers.at(cp_index) = status; 236 } 237 // We use a special internal bytecode for such methods (if non-static). 238 // The basic reason for this is that such methods need an extra "appendix" argument 239 // to transmit the call site's intended call type. 240 if (status > 0) { 241 (*opc) = (u1)Bytecodes::_invokehandle; 242 } 243 } 244 } else { 245 // Do not need to look at cp_index. 246 if ((*opc) == (u1)Bytecodes::_invokehandle) { 247 (*opc) = (u1)Bytecodes::_invokevirtual; 248 // Ignore corner case of original _invokespecial instruction. 249 // This is safe because (a) the signature polymorphic method was final, and 250 // (b) the implementation of MethodHandle will not call invokespecial on it. 251 } 252 } 253 } 254 255 256 void Rewriter::rewrite_invokedynamic(address bcp, int offset, bool reverse) { 257 address p = bcp + offset; 258 assert(p[-1] == Bytecodes::_invokedynamic, "not invokedynamic bytecode"); 259 if (!reverse) { 260 int cp_index = Bytes::get_Java_u2(p); 261 int cache_index = add_invokedynamic_cp_cache_entry(cp_index); 262 int resolved_index = add_invokedynamic_resolved_references_entries(cp_index, cache_index); 263 // Replace the trailing four bytes with a CPC index for the dynamic 264 // call site. Unlike other CPC entries, there is one per bytecode, 265 // not just one per distinct CP entry. In other words, the 266 // CPC-to-CP relation is many-to-one for invokedynamic entries. 267 // This means we must use a larger index size than u2 to address 268 // all these entries. That is the main reason invokedynamic 269 // must have a five-byte instruction format. (Of course, other JVM 270 // implementations can use the bytes for other purposes.) 271 // Note: We use native_u4 format exclusively for 4-byte indexes. 272 Bytes::put_native_u4(p, ConstantPool::encode_invokedynamic_index(cache_index)); 273 // add the bcp in case we need to patch this bytecode if we also find a 274 // invokespecial/InterfaceMethodref in the bytecode stream 275 _patch_invokedynamic_bcps->push(p); 276 _patch_invokedynamic_refs->push(resolved_index); 277 } else { 278 int cache_index = ConstantPool::decode_invokedynamic_index( 279 Bytes::get_native_u4(p)); 280 // We will reverse the bytecode rewriting _after_ adjusting them. 281 // Adjust the cache index by offset to the invokedynamic entries in the 282 // cpCache plus the delta if the invokedynamic bytecodes were adjusted. 283 int adjustment = cp_cache_delta() + _first_iteration_cp_cache_limit; 284 int cp_index = invokedynamic_cp_cache_entry_pool_index(cache_index - adjustment); 285 assert(_pool->tag_at(cp_index).is_invoke_dynamic(), "wrong index"); 286 // zero out 4 bytes 287 Bytes::put_Java_u4(p, 0); 288 Bytes::put_Java_u2(p, cp_index); 289 } 290 } 291 292 void Rewriter::patch_invokedynamic_bytecodes() { 293 // If the end of the cp_cache is the same as after initializing with the 294 // cpool, nothing needs to be done. Invokedynamic bytecodes are at the 295 // correct offsets. ie. no invokespecials added 296 int delta = cp_cache_delta(); 297 if (delta > 0) { 298 int length = _patch_invokedynamic_bcps->length(); 299 assert(length == _patch_invokedynamic_refs->length(), 300 "lengths should match"); 301 for (int i = 0; i < length; i++) { 302 address p = _patch_invokedynamic_bcps->at(i); 303 int cache_index = ConstantPool::decode_invokedynamic_index( 304 Bytes::get_native_u4(p)); 305 Bytes::put_native_u4(p, ConstantPool::encode_invokedynamic_index(cache_index + delta)); 306 307 // invokedynamic resolved references map also points to cp cache and must 308 // add delta to each. 309 int resolved_index = _patch_invokedynamic_refs->at(i); 310 for (int entry = 0; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) { 311 assert(_invokedynamic_references_map.at(resolved_index + entry) == cache_index, 312 "should be the same index"); 313 _invokedynamic_references_map.at_put(resolved_index+entry, 314 cache_index + delta); 315 } 316 } 317 } 318 } 319 320 321 // Rewrite some ldc bytecodes to _fast_aldc 322 void Rewriter::maybe_rewrite_ldc(address bcp, int offset, bool is_wide, 323 bool reverse) { 324 if (!reverse) { 325 assert((*bcp) == (is_wide ? Bytecodes::_ldc_w : Bytecodes::_ldc), "not ldc bytecode"); 326 address p = bcp + offset; 327 int cp_index = is_wide ? Bytes::get_Java_u2(p) : (u1)(*p); 328 constantTag tag = _pool->tag_at(cp_index).value(); 329 330 if (tag.is_method_handle() || 331 tag.is_method_type() || 332 tag.is_string() || 333 (tag.is_dynamic_constant() && 334 // keep regular ldc interpreter logic for condy primitives 335 is_reference_type(FieldType::basic_type(_pool->uncached_signature_ref_at(cp_index)))) 336 ) { 337 int ref_index = cp_entry_to_resolved_references(cp_index); 338 if (is_wide) { 339 (*bcp) = Bytecodes::_fast_aldc_w; 340 assert(ref_index == (u2)ref_index, "index overflow"); 341 Bytes::put_native_u2(p, ref_index); 342 } else { 343 (*bcp) = Bytecodes::_fast_aldc; 344 assert(ref_index == (u1)ref_index, "index overflow"); 345 (*p) = (u1)ref_index; 346 } 347 } 348 } else { 349 Bytecodes::Code rewritten_bc = 350 (is_wide ? Bytecodes::_fast_aldc_w : Bytecodes::_fast_aldc); 351 if ((*bcp) == rewritten_bc) { 352 address p = bcp + offset; 353 int ref_index = is_wide ? Bytes::get_native_u2(p) : (u1)(*p); 354 int pool_index = resolved_references_entry_to_pool_index(ref_index); 355 if (is_wide) { 356 (*bcp) = Bytecodes::_ldc_w; 357 assert(pool_index == (u2)pool_index, "index overflow"); 358 Bytes::put_Java_u2(p, pool_index); 359 } else { 360 (*bcp) = Bytecodes::_ldc; 361 assert(pool_index == (u1)pool_index, "index overflow"); 362 (*p) = (u1)pool_index; 363 } 364 } 365 } 366 } 367 368 369 // Rewrites a method given the index_map information 370 void Rewriter::scan_method(Method* method, bool reverse, bool* invokespecial_error) { 371 372 int nof_jsrs = 0; 373 bool has_monitor_bytecodes = false; 374 Bytecodes::Code c; 375 376 // Bytecodes and their length 377 const address code_base = method->code_base(); 378 const int code_length = method->code_size(); 379 380 int bc_length; 381 for (int bci = 0; bci < code_length; bci += bc_length) { 382 address bcp = code_base + bci; 383 int prefix_length = 0; 384 c = (Bytecodes::Code)(*bcp); 385 386 // Since we have the code, see if we can get the length 387 // directly. Some more complicated bytecodes will report 388 // a length of zero, meaning we need to make another method 389 // call to calculate the length. 390 bc_length = Bytecodes::length_for(c); 391 if (bc_length == 0) { 392 bc_length = Bytecodes::length_at(method, bcp); 393 394 // length_at will put us at the bytecode after the one modified 395 // by 'wide'. We don't currently examine any of the bytecodes 396 // modified by wide, but in case we do in the future... 397 if (c == Bytecodes::_wide) { 398 prefix_length = 1; 399 c = (Bytecodes::Code)bcp[1]; 400 } 401 } 402 403 assert(bc_length != 0, "impossible bytecode length"); 404 405 switch (c) { 406 case Bytecodes::_lookupswitch : { 407 #ifndef CC_INTERP 408 Bytecode_lookupswitch bc(method, bcp); 409 (*bcp) = ( 410 bc.number_of_pairs() < BinarySwitchThreshold 411 ? Bytecodes::_fast_linearswitch 412 : Bytecodes::_fast_binaryswitch 413 ); 414 #endif 415 break; 416 } 417 case Bytecodes::_fast_linearswitch: 418 case Bytecodes::_fast_binaryswitch: { 419 #ifndef CC_INTERP 420 (*bcp) = Bytecodes::_lookupswitch; 421 #endif 422 break; 423 } 424 425 case Bytecodes::_invokespecial : { 426 rewrite_invokespecial(bcp, prefix_length+1, reverse, invokespecial_error); 427 break; 428 } 429 430 case Bytecodes::_putstatic : 431 case Bytecodes::_putfield : { 432 if (!reverse) { 433 // Check if any final field of the class given as parameter is modified 434 // outside of initializer methods of the class. Fields that are modified 435 // are marked with a flag. For marked fields, the compilers do not perform 436 // constant folding (as the field can be changed after initialization). 437 // 438 // The check is performed after verification and only if verification has 439 // succeeded. Therefore, the class is guaranteed to be well-formed. 440 InstanceKlass* klass = method->method_holder(); 441 u2 bc_index = Bytes::get_Java_u2(bcp + prefix_length + 1); 442 constantPoolHandle cp(method->constants()); 443 Symbol* ref_class_name = cp->klass_name_at(cp->klass_ref_index_at(bc_index)); 444 445 if (klass->name() == ref_class_name) { 446 Symbol* field_name = cp->name_ref_at(bc_index); 447 Symbol* field_sig = cp->signature_ref_at(bc_index); 448 449 fieldDescriptor fd; 450 if (klass->find_field(field_name, field_sig, &fd) != NULL) { 451 if (fd.access_flags().is_final()) { 452 if (fd.access_flags().is_static()) { 453 if (!method->is_static_initializer()) { 454 fd.set_has_initialized_final_update(true); 455 } 456 } else { 457 if (!method->is_object_initializer()) { 458 fd.set_has_initialized_final_update(true); 459 } 460 } 461 } 462 } 463 } 464 } 465 } 466 // fall through 467 case Bytecodes::_getstatic : // fall through 468 case Bytecodes::_getfield : // fall through 469 case Bytecodes::_invokevirtual : // fall through 470 case Bytecodes::_invokestatic : 471 case Bytecodes::_invokeinterface: 472 case Bytecodes::_invokehandle : // if reverse=true 473 rewrite_member_reference(bcp, prefix_length+1, reverse); 474 break; 475 case Bytecodes::_invokedynamic: 476 rewrite_invokedynamic(bcp, prefix_length+1, reverse); 477 break; 478 case Bytecodes::_ldc: 479 case Bytecodes::_fast_aldc: // if reverse=true 480 maybe_rewrite_ldc(bcp, prefix_length+1, false, reverse); 481 break; 482 case Bytecodes::_ldc_w: 483 case Bytecodes::_fast_aldc_w: // if reverse=true 484 maybe_rewrite_ldc(bcp, prefix_length+1, true, reverse); 485 break; 486 case Bytecodes::_jsr : // fall through 487 case Bytecodes::_jsr_w : nof_jsrs++; break; 488 case Bytecodes::_monitorenter : // fall through 489 case Bytecodes::_monitorexit : has_monitor_bytecodes = true; break; 490 491 default: break; 492 } 493 } 494 495 // Update access flags 496 if (has_monitor_bytecodes) { 497 method->set_has_monitor_bytecodes(); 498 } 499 500 // The present of a jsr bytecode implies that the method might potentially 501 // have to be rewritten, so we run the oopMapGenerator on the method 502 if (nof_jsrs > 0) { 503 method->set_has_jsrs(); 504 // Second pass will revisit this method. 505 assert(method->has_jsrs(), "didn't we just set this?"); 506 } 507 } 508 509 // After constant pool is created, revisit methods containing jsrs. 510 methodHandle Rewriter::rewrite_jsrs(const methodHandle& method, TRAPS) { 511 ResourceMark rm(THREAD); 512 ResolveOopMapConflicts romc(method); 513 methodHandle new_method = romc.do_potential_rewrite(CHECK_(methodHandle())); 514 // Update monitor matching info. 515 if (romc.monitor_safe()) { 516 new_method->set_guaranteed_monitor_matching(); 517 } 518 519 return new_method; 520 } 521 522 void Rewriter::rewrite_bytecodes(TRAPS) { 523 assert(_pool->cache() == NULL, "constant pool cache must not be set yet"); 524 525 // determine index maps for Method* rewriting 526 compute_index_maps(); 527 528 if (RegisterFinalizersAtInit && _klass->name() == vmSymbols::java_lang_Object()) { 529 bool did_rewrite = false; 530 int i = _methods->length(); 531 while (i-- > 0) { 532 Method* method = _methods->at(i); 533 if (method->intrinsic_id() == vmIntrinsics::_Object_init) { 534 // rewrite the return bytecodes of Object.<init> to register the 535 // object for finalization if needed. 536 methodHandle m(THREAD, method); 537 rewrite_Object_init(m, CHECK); 538 did_rewrite = true; 539 break; 540 } 541 } 542 assert(did_rewrite, "must find Object::<init> to rewrite it"); 543 } 544 545 // rewrite methods, in two passes 546 int len = _methods->length(); 547 bool invokespecial_error = false; 548 549 for (int i = len-1; i >= 0; i--) { 550 Method* method = _methods->at(i); 551 scan_method(method, false, &invokespecial_error); 552 if (invokespecial_error) { 553 // If you get an error here, there is no reversing bytecodes 554 // This exception is stored for this class and no further attempt is 555 // made at verifying or rewriting. 556 THROW_MSG(vmSymbols::java_lang_InternalError(), 557 "This classfile overflows invokespecial for interfaces " 558 "and cannot be loaded"); 559 return; 560 } 561 } 562 563 // May have to fix invokedynamic bytecodes if invokestatic/InterfaceMethodref 564 // entries had to be added. 565 patch_invokedynamic_bytecodes(); 566 } 567 568 void Rewriter::rewrite(InstanceKlass* klass, TRAPS) { 569 if (!DumpSharedSpaces) { 570 assert(!klass->is_shared(), "archive methods must not be rewritten at run time"); 571 } 572 ResourceMark rm(THREAD); 573 Rewriter rw(klass, klass->constants(), klass->methods(), CHECK); 574 // (That's all, folks.) 575 } 576 577 Rewriter::Rewriter(InstanceKlass* klass, const constantPoolHandle& cpool, Array<Method*>* methods, TRAPS) 578 : _klass(klass), 579 _pool(cpool), 580 _methods(methods), 581 _cp_map(cpool->length()), 582 _cp_cache_map(cpool->length() / 2), 583 _reference_map(cpool->length()), 584 _resolved_references_map(cpool->length() / 2), 585 _invokedynamic_references_map(cpool->length() / 2), 586 _method_handle_invokers(cpool->length()), 587 _invokedynamic_cp_cache_map(cpool->length() / 4) 588 { 589 590 // Rewrite bytecodes - exception here exits. 591 rewrite_bytecodes(CHECK); 592 593 // Stress restoring bytecodes 594 if (StressRewriter) { 595 restore_bytecodes(); 596 rewrite_bytecodes(CHECK); 597 } 598 599 // allocate constant pool cache, now that we've seen all the bytecodes 600 make_constant_pool_cache(THREAD); 601 602 // Restore bytecodes to their unrewritten state if there are exceptions 603 // rewriting bytecodes or allocating the cpCache 604 if (HAS_PENDING_EXCEPTION) { 605 restore_bytecodes(); 606 return; 607 } 608 609 // Relocate after everything, but still do this under the is_rewritten flag, 610 // so methods with jsrs in custom class lists in aren't attempted to be 611 // rewritten in the RO section of the shared archive. 612 // Relocated bytecodes don't have to be restored, only the cp cache entries 613 int len = _methods->length(); 614 for (int i = len-1; i >= 0; i--) { 615 methodHandle m(THREAD, _methods->at(i)); 616 617 if (m->has_jsrs()) { 618 m = rewrite_jsrs(m, THREAD); 619 // Restore bytecodes to their unrewritten state if there are exceptions 620 // relocating bytecodes. If some are relocated, that is ok because that 621 // doesn't affect constant pool to cpCache rewriting. 622 if (HAS_PENDING_EXCEPTION) { 623 restore_bytecodes(); 624 return; 625 } 626 // Method might have gotten rewritten. 627 methods->at_put(i, m()); 628 } 629 } 630 }