1 /* 2 * Copyright (c) 1997, 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 "classfile/metadataOnStackMark.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "code/codeCache.hpp" 29 #include "code/debugInfoRec.hpp" 30 #include "gc/shared/collectedHeap.inline.hpp" 31 #include "gc/shared/gcLocker.hpp" 32 #include "gc/shared/generation.hpp" 33 #include "interpreter/bytecodeStream.hpp" 34 #include "interpreter/bytecodeTracer.hpp" 35 #include "interpreter/bytecodes.hpp" 36 #include "interpreter/interpreter.hpp" 37 #include "interpreter/oopMapCache.hpp" 38 #include "memory/heapInspection.hpp" 39 #include "memory/metadataFactory.hpp" 40 #include "memory/metaspaceClosure.hpp" 41 #include "memory/metaspaceShared.hpp" 42 #include "memory/oopFactory.hpp" 43 #include "memory/resourceArea.hpp" 44 #include "oops/constMethod.hpp" 45 #include "oops/method.inline.hpp" 46 #include "oops/methodData.hpp" 47 #include "oops/objArrayOop.inline.hpp" 48 #include "oops/oop.inline.hpp" 49 #include "oops/symbol.hpp" 50 #include "prims/jvmtiExport.hpp" 51 #include "prims/methodHandles.hpp" 52 #include "prims/nativeLookup.hpp" 53 #include "runtime/arguments.hpp" 54 #include "runtime/compilationPolicy.hpp" 55 #include "runtime/frame.inline.hpp" 56 #include "runtime/handles.inline.hpp" 57 #include "runtime/init.hpp" 58 #include "runtime/orderAccess.inline.hpp" 59 #include "runtime/relocator.hpp" 60 #include "runtime/sharedRuntime.hpp" 61 #include "runtime/signature.hpp" 62 #include "utilities/align.hpp" 63 #include "utilities/quickSort.hpp" 64 #include "utilities/vmError.hpp" 65 #include "utilities/xmlstream.hpp" 66 67 // Implementation of Method 68 69 Method* Method::allocate(ClassLoaderData* loader_data, 70 int byte_code_size, 71 AccessFlags access_flags, 72 InlineTableSizes* sizes, 73 ConstMethod::MethodType method_type, 74 TRAPS) { 75 assert(!access_flags.is_native() || byte_code_size == 0, 76 "native methods should not contain byte codes"); 77 ConstMethod* cm = ConstMethod::allocate(loader_data, 78 byte_code_size, 79 sizes, 80 method_type, 81 CHECK_NULL); 82 int size = Method::size(access_flags.is_native()); 83 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags); 84 } 85 86 Method::Method(ConstMethod* xconst, AccessFlags access_flags) { 87 NoSafepointVerifier no_safepoint; 88 set_constMethod(xconst); 89 set_access_flags(access_flags); 90 set_intrinsic_id(vmIntrinsics::_none); 91 set_force_inline(false); 92 set_hidden(false); 93 set_dont_inline(false); 94 set_has_injected_profile(false); 95 set_method_data(NULL); 96 clear_method_counters(); 97 set_vtable_index(Method::garbage_vtable_index); 98 99 // Fix and bury in Method* 100 set_interpreter_entry(NULL); // sets i2i entry and from_int 101 set_adapter_entry(NULL); 102 clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i 103 104 if (access_flags.is_native()) { 105 clear_native_function(); 106 set_signature_handler(NULL); 107 } 108 109 NOT_PRODUCT(set_compiled_invocation_count(0);) 110 } 111 112 // Release Method*. The nmethod will be gone when we get here because 113 // we've walked the code cache. 114 void Method::deallocate_contents(ClassLoaderData* loader_data) { 115 MetadataFactory::free_metadata(loader_data, constMethod()); 116 set_constMethod(NULL); 117 MetadataFactory::free_metadata(loader_data, method_data()); 118 set_method_data(NULL); 119 MetadataFactory::free_metadata(loader_data, method_counters()); 120 clear_method_counters(); 121 // The nmethod will be gone when we get here. 122 if (code() != NULL) _code = NULL; 123 } 124 125 address Method::get_i2c_entry() { 126 assert(adapter() != NULL, "must have"); 127 return adapter()->get_i2c_entry(); 128 } 129 130 address Method::get_c2i_entry() { 131 assert(adapter() != NULL, "must have"); 132 return adapter()->get_c2i_entry(); 133 } 134 135 address Method::get_c2i_unverified_entry() { 136 assert(adapter() != NULL, "must have"); 137 return adapter()->get_c2i_unverified_entry(); 138 } 139 140 char* Method::name_and_sig_as_C_string() const { 141 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature()); 142 } 143 144 char* Method::name_and_sig_as_C_string(char* buf, int size) const { 145 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size); 146 } 147 148 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) { 149 const char* klass_name = klass->external_name(); 150 int klass_name_len = (int)strlen(klass_name); 151 int method_name_len = method_name->utf8_length(); 152 int len = klass_name_len + 1 + method_name_len + signature->utf8_length(); 153 char* dest = NEW_RESOURCE_ARRAY(char, len + 1); 154 strcpy(dest, klass_name); 155 dest[klass_name_len] = '.'; 156 strcpy(&dest[klass_name_len + 1], method_name->as_C_string()); 157 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string()); 158 dest[len] = 0; 159 return dest; 160 } 161 162 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) { 163 Symbol* klass_name = klass->name(); 164 klass_name->as_klass_external_name(buf, size); 165 int len = (int)strlen(buf); 166 167 if (len < size - 1) { 168 buf[len++] = '.'; 169 170 method_name->as_C_string(&(buf[len]), size - len); 171 len = (int)strlen(buf); 172 173 signature->as_C_string(&(buf[len]), size - len); 174 } 175 176 return buf; 177 } 178 179 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) { 180 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index) 181 // access exception table 182 ExceptionTable table(mh()); 183 int length = table.length(); 184 // iterate through all entries sequentially 185 constantPoolHandle pool(THREAD, mh->constants()); 186 for (int i = 0; i < length; i ++) { 187 //reacquire the table in case a GC happened 188 ExceptionTable table(mh()); 189 int beg_bci = table.start_pc(i); 190 int end_bci = table.end_pc(i); 191 assert(beg_bci <= end_bci, "inconsistent exception table"); 192 if (beg_bci <= throw_bci && throw_bci < end_bci) { 193 // exception handler bci range covers throw_bci => investigate further 194 int handler_bci = table.handler_pc(i); 195 int klass_index = table.catch_type_index(i); 196 if (klass_index == 0) { 197 return handler_bci; 198 } else if (ex_klass == NULL) { 199 return handler_bci; 200 } else { 201 // we know the exception class => get the constraint class 202 // this may require loading of the constraint class; if verification 203 // fails or some other exception occurs, return handler_bci 204 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci)); 205 assert(k != NULL, "klass not loaded"); 206 if (ex_klass->is_subtype_of(k)) { 207 return handler_bci; 208 } 209 } 210 } 211 } 212 213 return -1; 214 } 215 216 void Method::mask_for(int bci, InterpreterOopMap* mask) { 217 methodHandle h_this(Thread::current(), this); 218 // Only GC uses the OopMapCache during thread stack root scanning 219 // any other uses generate an oopmap but do not save it in the cache. 220 if (Universe::heap()->is_gc_active()) { 221 method_holder()->mask_for(h_this, bci, mask); 222 } else { 223 OopMapCache::compute_one_oop_map(h_this, bci, mask); 224 } 225 return; 226 } 227 228 229 int Method::bci_from(address bcp) const { 230 if (is_native() && bcp == 0) { 231 return 0; 232 } 233 #ifdef ASSERT 234 { 235 ResourceMark rm; 236 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(), 237 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", 238 p2i(bcp), name_and_sig_as_C_string()); 239 } 240 #endif 241 return bcp - code_base(); 242 } 243 244 245 int Method::validate_bci(int bci) const { 246 return (bci == 0 || bci < code_size()) ? bci : -1; 247 } 248 249 // Return bci if it appears to be a valid bcp 250 // Return -1 otherwise. 251 // Used by profiling code, when invalid data is a possibility. 252 // The caller is responsible for validating the Method* itself. 253 int Method::validate_bci_from_bcp(address bcp) const { 254 // keep bci as -1 if not a valid bci 255 int bci = -1; 256 if (bcp == 0 || bcp == code_base()) { 257 // code_size() may return 0 and we allow 0 here 258 // the method may be native 259 bci = 0; 260 } else if (contains(bcp)) { 261 bci = bcp - code_base(); 262 } 263 // Assert that if we have dodged any asserts, bci is negative. 264 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0"); 265 return bci; 266 } 267 268 address Method::bcp_from(int bci) const { 269 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()), 270 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native"); 271 address bcp = code_base() + bci; 272 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method"); 273 return bcp; 274 } 275 276 address Method::bcp_from(address bcp) const { 277 if (is_native() && bcp == NULL) { 278 return code_base(); 279 } else { 280 return bcp; 281 } 282 } 283 284 int Method::size(bool is_native) { 285 // If native, then include pointers for native_function and signature_handler 286 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0; 287 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord; 288 return align_metadata_size(header_size() + extra_words); 289 } 290 291 292 Symbol* Method::klass_name() const { 293 return method_holder()->name(); 294 } 295 296 297 void Method::metaspace_pointers_do(MetaspaceClosure* it) { 298 log_trace(cds)("Iter(Method): %p", this); 299 300 it->push(&_constMethod); 301 it->push(&_method_data); 302 it->push(&_method_counters); 303 } 304 305 // Attempt to return method oop to original state. Clear any pointers 306 // (to objects outside the shared spaces). We won't be able to predict 307 // where they should point in a new JVM. Further initialize some 308 // entries now in order allow them to be write protected later. 309 310 void Method::remove_unshareable_info() { 311 unlink_method(); 312 } 313 314 void Method::set_vtable_index(int index) { 315 if (is_shared() && !MetaspaceShared::remapped_readwrite()) { 316 // At runtime initialize_vtable is rerun as part of link_class_impl() 317 // for a shared class loaded by the non-boot loader to obtain the loader 318 // constraints based on the runtime classloaders' context. 319 return; // don't write into the shared class 320 } else { 321 _vtable_index = index; 322 } 323 } 324 325 void Method::set_itable_index(int index) { 326 if (is_shared() && !MetaspaceShared::remapped_readwrite()) { 327 // At runtime initialize_itable is rerun as part of link_class_impl() 328 // for a shared class loaded by the non-boot loader to obtain the loader 329 // constraints based on the runtime classloaders' context. The dumptime 330 // itable index should be the same as the runtime index. 331 assert(_vtable_index == itable_index_max - index, 332 "archived itable index is different from runtime index"); 333 return; // don’t write into the shared class 334 } else { 335 _vtable_index = itable_index_max - index; 336 } 337 assert(valid_itable_index(), ""); 338 } 339 340 341 342 bool Method::was_executed_more_than(int n) { 343 // Invocation counter is reset when the Method* is compiled. 344 // If the method has compiled code we therefore assume it has 345 // be excuted more than n times. 346 if (is_accessor() || is_empty_method() || (code() != NULL)) { 347 // interpreter doesn't bump invocation counter of trivial methods 348 // compiler does not bump invocation counter of compiled methods 349 return true; 350 } 351 else if ((method_counters() != NULL && 352 method_counters()->invocation_counter()->carry()) || 353 (method_data() != NULL && 354 method_data()->invocation_counter()->carry())) { 355 // The carry bit is set when the counter overflows and causes 356 // a compilation to occur. We don't know how many times 357 // the counter has been reset, so we simply assume it has 358 // been executed more than n times. 359 return true; 360 } else { 361 return invocation_count() > n; 362 } 363 } 364 365 void Method::print_invocation_count() { 366 if (is_static()) tty->print("static "); 367 if (is_final()) tty->print("final "); 368 if (is_synchronized()) tty->print("synchronized "); 369 if (is_native()) tty->print("native "); 370 tty->print("%s::", method_holder()->external_name()); 371 name()->print_symbol_on(tty); 372 signature()->print_symbol_on(tty); 373 374 if (WizardMode) { 375 // dump the size of the byte codes 376 tty->print(" {%d}", code_size()); 377 } 378 tty->cr(); 379 380 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count()); 381 tty->print_cr (" invocation_counter: %8d ", invocation_count()); 382 tty->print_cr (" backedge_counter: %8d ", backedge_count()); 383 #ifndef PRODUCT 384 if (CountCompiledCalls) { 385 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count()); 386 } 387 #endif 388 } 389 390 // Build a MethodData* object to hold information about this method 391 // collected in the interpreter. 392 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) { 393 // Do not profile the method if metaspace has hit an OOM previously 394 // allocating profiling data. Callers clear pending exception so don't 395 // add one here. 396 if (ClassLoaderDataGraph::has_metaspace_oom()) { 397 return; 398 } 399 400 // Grab a lock here to prevent multiple 401 // MethodData*s from being created. 402 MutexLocker ml(MethodData_lock, THREAD); 403 if (method->method_data() == NULL) { 404 ClassLoaderData* loader_data = method->method_holder()->class_loader_data(); 405 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD); 406 if (HAS_PENDING_EXCEPTION) { 407 CompileBroker::log_metaspace_failure(); 408 ClassLoaderDataGraph::set_metaspace_oom(true); 409 return; // return the exception (which is cleared) 410 } 411 412 method->set_method_data(method_data); 413 if (PrintMethodData && (Verbose || WizardMode)) { 414 ResourceMark rm(THREAD); 415 tty->print("build_interpreter_method_data for "); 416 method->print_name(tty); 417 tty->cr(); 418 // At the end of the run, the MDO, full of data, will be dumped. 419 } 420 } 421 } 422 423 MethodCounters* Method::build_method_counters(Method* m, TRAPS) { 424 // Do not profile the method if metaspace has hit an OOM previously 425 if (ClassLoaderDataGraph::has_metaspace_oom()) { 426 return NULL; 427 } 428 429 methodHandle mh(m); 430 MethodCounters* counters = MethodCounters::allocate(mh, THREAD); 431 if (HAS_PENDING_EXCEPTION) { 432 CompileBroker::log_metaspace_failure(); 433 ClassLoaderDataGraph::set_metaspace_oom(true); 434 return NULL; // return the exception (which is cleared) 435 } 436 if (!mh->init_method_counters(counters)) { 437 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters); 438 } 439 440 if (LogTouchedMethods) { 441 mh->log_touched(CHECK_NULL); 442 } 443 444 return mh->method_counters(); 445 } 446 447 bool Method::init_method_counters(MethodCounters* counters) { 448 // Try to install a pointer to MethodCounters, return true on success. 449 return Atomic::replace_if_null(counters, &_method_counters); 450 } 451 452 void Method::cleanup_inline_caches() { 453 // The current system doesn't use inline caches in the interpreter 454 // => nothing to do (keep this method around for future use) 455 } 456 457 458 int Method::extra_stack_words() { 459 // not an inline function, to avoid a header dependency on Interpreter 460 return extra_stack_entries() * Interpreter::stackElementSize; 461 } 462 463 464 void Method::compute_size_of_parameters(Thread *thread) { 465 ArgumentSizeComputer asc(signature()); 466 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1)); 467 } 468 469 BasicType Method::result_type() const { 470 ResultTypeFinder rtf(signature()); 471 return rtf.type(); 472 } 473 474 475 bool Method::is_empty_method() const { 476 return code_size() == 1 477 && *code_base() == Bytecodes::_return; 478 } 479 480 481 bool Method::is_vanilla_constructor() const { 482 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method 483 // which only calls the superclass vanilla constructor and possibly does stores of 484 // zero constants to local fields: 485 // 486 // aload_0 487 // invokespecial 488 // indexbyte1 489 // indexbyte2 490 // 491 // followed by an (optional) sequence of: 492 // 493 // aload_0 494 // aconst_null / iconst_0 / fconst_0 / dconst_0 495 // putfield 496 // indexbyte1 497 // indexbyte2 498 // 499 // followed by: 500 // 501 // return 502 503 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors"); 504 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors"); 505 int size = code_size(); 506 // Check if size match 507 if (size == 0 || size % 5 != 0) return false; 508 address cb = code_base(); 509 int last = size - 1; 510 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) { 511 // Does not call superclass default constructor 512 return false; 513 } 514 // Check optional sequence 515 for (int i = 4; i < last; i += 5) { 516 if (cb[i] != Bytecodes::_aload_0) return false; 517 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false; 518 if (cb[i+2] != Bytecodes::_putfield) return false; 519 } 520 return true; 521 } 522 523 524 bool Method::compute_has_loops_flag() { 525 BytecodeStream bcs(this); 526 Bytecodes::Code bc; 527 528 while ((bc = bcs.next()) >= 0) { 529 switch( bc ) { 530 case Bytecodes::_ifeq: 531 case Bytecodes::_ifnull: 532 case Bytecodes::_iflt: 533 case Bytecodes::_ifle: 534 case Bytecodes::_ifne: 535 case Bytecodes::_ifnonnull: 536 case Bytecodes::_ifgt: 537 case Bytecodes::_ifge: 538 case Bytecodes::_if_icmpeq: 539 case Bytecodes::_if_icmpne: 540 case Bytecodes::_if_icmplt: 541 case Bytecodes::_if_icmpgt: 542 case Bytecodes::_if_icmple: 543 case Bytecodes::_if_icmpge: 544 case Bytecodes::_if_acmpeq: 545 case Bytecodes::_if_acmpne: 546 case Bytecodes::_goto: 547 case Bytecodes::_jsr: 548 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops(); 549 break; 550 551 case Bytecodes::_goto_w: 552 case Bytecodes::_jsr_w: 553 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops(); 554 break; 555 556 default: 557 break; 558 } 559 } 560 _access_flags.set_loops_flag_init(); 561 return _access_flags.has_loops(); 562 } 563 564 bool Method::is_final_method(AccessFlags class_access_flags) const { 565 // or "does_not_require_vtable_entry" 566 // default method or overpass can occur, is not final (reuses vtable entry) 567 // private methods in classes get vtable entries for backward class compatibility. 568 if (is_overpass() || is_default_method()) return false; 569 return is_final() || class_access_flags.is_final(); 570 } 571 572 bool Method::is_final_method() const { 573 return is_final_method(method_holder()->access_flags()); 574 } 575 576 bool Method::is_default_method() const { 577 if (method_holder() != NULL && 578 method_holder()->is_interface() && 579 !is_abstract() && !is_private()) { 580 return true; 581 } else { 582 return false; 583 } 584 } 585 586 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const { 587 if (is_final_method(class_access_flags)) return true; 588 #ifdef ASSERT 589 ResourceMark rm; 590 bool is_nonv = (vtable_index() == nonvirtual_vtable_index); 591 if (class_access_flags.is_interface()) { 592 assert(is_nonv == is_static() || is_nonv == is_private(), 593 "nonvirtual unexpected for non-static, non-private: %s", 594 name_and_sig_as_C_string()); 595 } 596 #endif 597 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question"); 598 return vtable_index() == nonvirtual_vtable_index; 599 } 600 601 bool Method::can_be_statically_bound() const { 602 return can_be_statically_bound(method_holder()->access_flags()); 603 } 604 605 bool Method::is_accessor() const { 606 return is_getter() || is_setter(); 607 } 608 609 bool Method::is_getter() const { 610 if (code_size() != 5) return false; 611 if (size_of_parameters() != 1) return false; 612 if (java_code_at(0) != Bytecodes::_aload_0) return false; 613 if (java_code_at(1) != Bytecodes::_getfield) return false; 614 switch (java_code_at(4)) { 615 case Bytecodes::_ireturn: 616 case Bytecodes::_lreturn: 617 case Bytecodes::_freturn: 618 case Bytecodes::_dreturn: 619 case Bytecodes::_areturn: 620 break; 621 default: 622 return false; 623 } 624 return true; 625 } 626 627 bool Method::is_setter() const { 628 if (code_size() != 6) return false; 629 if (java_code_at(0) != Bytecodes::_aload_0) return false; 630 switch (java_code_at(1)) { 631 case Bytecodes::_iload_1: 632 case Bytecodes::_aload_1: 633 case Bytecodes::_fload_1: 634 if (size_of_parameters() != 2) return false; 635 break; 636 case Bytecodes::_dload_1: 637 case Bytecodes::_lload_1: 638 if (size_of_parameters() != 3) return false; 639 break; 640 default: 641 return false; 642 } 643 if (java_code_at(2) != Bytecodes::_putfield) return false; 644 if (java_code_at(5) != Bytecodes::_return) return false; 645 return true; 646 } 647 648 bool Method::is_constant_getter() const { 649 int last_index = code_size() - 1; 650 // Check if the first 1-3 bytecodes are a constant push 651 // and the last bytecode is a return. 652 return (2 <= code_size() && code_size() <= 4 && 653 Bytecodes::is_const(java_code_at(0)) && 654 Bytecodes::length_for(java_code_at(0)) == last_index && 655 Bytecodes::is_return(java_code_at(last_index))); 656 } 657 658 bool Method::is_initializer() const { 659 return is_object_initializer() || is_static_initializer(); 660 } 661 662 bool Method::has_valid_initializer_flags() const { 663 return (is_static() || 664 method_holder()->major_version() < 51); 665 } 666 667 bool Method::is_static_initializer() const { 668 // For classfiles version 51 or greater, ensure that the clinit method is 669 // static. Non-static methods with the name "<clinit>" are not static 670 // initializers. (older classfiles exempted for backward compatibility) 671 return name() == vmSymbols::class_initializer_name() && 672 has_valid_initializer_flags(); 673 } 674 675 bool Method::is_object_initializer() const { 676 return name() == vmSymbols::object_initializer_name(); 677 } 678 679 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) { 680 int length = method->checked_exceptions_length(); 681 if (length == 0) { // common case 682 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array()); 683 } else { 684 methodHandle h_this(THREAD, method); 685 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle())); 686 objArrayHandle mirrors (THREAD, m_oop); 687 for (int i = 0; i < length; i++) { 688 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe 689 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle())); 690 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class"); 691 mirrors->obj_at_put(i, k->java_mirror()); 692 } 693 return mirrors; 694 } 695 }; 696 697 698 int Method::line_number_from_bci(int bci) const { 699 if (bci == SynchronizationEntryBCI) bci = 0; 700 assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci"); 701 int best_bci = 0; 702 int best_line = -1; 703 704 if (has_linenumber_table()) { 705 // The line numbers are a short array of 2-tuples [start_pc, line_number]. 706 // Not necessarily sorted and not necessarily one-to-one. 707 CompressedLineNumberReadStream stream(compressed_linenumber_table()); 708 while (stream.read_pair()) { 709 if (stream.bci() == bci) { 710 // perfect match 711 return stream.line(); 712 } else { 713 // update best_bci/line 714 if (stream.bci() < bci && stream.bci() >= best_bci) { 715 best_bci = stream.bci(); 716 best_line = stream.line(); 717 } 718 } 719 } 720 } 721 return best_line; 722 } 723 724 725 bool Method::is_klass_loaded_by_klass_index(int klass_index) const { 726 if( constants()->tag_at(klass_index).is_unresolved_klass() ) { 727 Thread *thread = Thread::current(); 728 Symbol* klass_name = constants()->klass_name_at(klass_index); 729 Handle loader(thread, method_holder()->class_loader()); 730 Handle prot (thread, method_holder()->protection_domain()); 731 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL; 732 } else { 733 return true; 734 } 735 } 736 737 738 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const { 739 int klass_index = constants()->klass_ref_index_at(refinfo_index); 740 if (must_be_resolved) { 741 // Make sure klass is resolved in constantpool. 742 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false; 743 } 744 return is_klass_loaded_by_klass_index(klass_index); 745 } 746 747 748 void Method::set_native_function(address function, bool post_event_flag) { 749 assert(function != NULL, "use clear_native_function to unregister natives"); 750 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), ""); 751 address* native_function = native_function_addr(); 752 753 // We can see racers trying to place the same native function into place. Once 754 // is plenty. 755 address current = *native_function; 756 if (current == function) return; 757 if (post_event_flag && JvmtiExport::should_post_native_method_bind() && 758 function != NULL) { 759 // native_method_throw_unsatisfied_link_error_entry() should only 760 // be passed when post_event_flag is false. 761 assert(function != 762 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), 763 "post_event_flag mis-match"); 764 765 // post the bind event, and possible change the bind function 766 JvmtiExport::post_native_method_bind(this, &function); 767 } 768 *native_function = function; 769 // This function can be called more than once. We must make sure that we always 770 // use the latest registered method -> check if a stub already has been generated. 771 // If so, we have to make it not_entrant. 772 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates 773 if (nm != NULL) { 774 nm->make_not_entrant(); 775 } 776 } 777 778 779 bool Method::has_native_function() const { 780 if (is_method_handle_intrinsic()) 781 return false; // special-cased in SharedRuntime::generate_native_wrapper 782 address func = native_function(); 783 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry()); 784 } 785 786 787 void Method::clear_native_function() { 788 // Note: is_method_handle_intrinsic() is allowed here. 789 set_native_function( 790 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), 791 !native_bind_event_is_interesting); 792 clear_code(); 793 } 794 795 address Method::critical_native_function() { 796 methodHandle mh(this); 797 return NativeLookup::lookup_critical_entry(mh); 798 } 799 800 801 void Method::set_signature_handler(address handler) { 802 address* signature_handler = signature_handler_addr(); 803 *signature_handler = handler; 804 } 805 806 807 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) { 808 if (PrintCompilation && report) { 809 ttyLocker ttyl; 810 tty->print("made not %scompilable on ", is_osr ? "OSR " : ""); 811 if (comp_level == CompLevel_all) { 812 tty->print("all levels "); 813 } else { 814 tty->print("levels "); 815 for (int i = (int)CompLevel_none; i <= comp_level; i++) { 816 tty->print("%d ", i); 817 } 818 } 819 this->print_short_name(tty); 820 int size = this->code_size(); 821 if (size > 0) { 822 tty->print(" (%d bytes)", size); 823 } 824 if (reason != NULL) { 825 tty->print(" %s", reason); 826 } 827 tty->cr(); 828 } 829 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) { 830 ttyLocker ttyl; 831 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'", 832 os::current_thread_id(), is_osr, comp_level); 833 if (reason != NULL) { 834 xtty->print(" reason=\'%s\'", reason); 835 } 836 xtty->method(this); 837 xtty->stamp(); 838 xtty->end_elem(); 839 } 840 } 841 842 bool Method::is_always_compilable() const { 843 // Generated adapters must be compiled 844 if (is_method_handle_intrinsic() && is_synthetic()) { 845 assert(!is_not_c1_compilable(), "sanity check"); 846 assert(!is_not_c2_compilable(), "sanity check"); 847 return true; 848 } 849 850 return false; 851 } 852 853 bool Method::is_not_compilable(int comp_level) const { 854 if (number_of_breakpoints() > 0) 855 return true; 856 if (is_always_compilable()) 857 return false; 858 if (comp_level == CompLevel_any) 859 return is_not_c1_compilable() || is_not_c2_compilable(); 860 if (is_c1_compile(comp_level)) 861 return is_not_c1_compilable(); 862 if (is_c2_compile(comp_level)) 863 return is_not_c2_compilable(); 864 return false; 865 } 866 867 // call this when compiler finds that this method is not compilable 868 void Method::set_not_compilable(int comp_level, bool report, const char* reason) { 869 if (is_always_compilable()) { 870 // Don't mark a method which should be always compilable 871 return; 872 } 873 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason); 874 if (comp_level == CompLevel_all) { 875 set_not_c1_compilable(); 876 set_not_c2_compilable(); 877 } else { 878 if (is_c1_compile(comp_level)) 879 set_not_c1_compilable(); 880 if (is_c2_compile(comp_level)) 881 set_not_c2_compilable(); 882 } 883 CompilationPolicy::policy()->disable_compilation(this); 884 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check"); 885 } 886 887 bool Method::is_not_osr_compilable(int comp_level) const { 888 if (is_not_compilable(comp_level)) 889 return true; 890 if (comp_level == CompLevel_any) 891 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable(); 892 if (is_c1_compile(comp_level)) 893 return is_not_c1_osr_compilable(); 894 if (is_c2_compile(comp_level)) 895 return is_not_c2_osr_compilable(); 896 return false; 897 } 898 899 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) { 900 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason); 901 if (comp_level == CompLevel_all) { 902 set_not_c1_osr_compilable(); 903 set_not_c2_osr_compilable(); 904 } else { 905 if (is_c1_compile(comp_level)) 906 set_not_c1_osr_compilable(); 907 if (is_c2_compile(comp_level)) 908 set_not_c2_osr_compilable(); 909 } 910 CompilationPolicy::policy()->disable_compilation(this); 911 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check"); 912 } 913 914 // Revert to using the interpreter and clear out the nmethod 915 void Method::clear_code(bool acquire_lock /* = true */) { 916 MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag); 917 // this may be NULL if c2i adapters have not been made yet 918 // Only should happen at allocate time. 919 if (adapter() == NULL) { 920 _from_compiled_entry = NULL; 921 } else { 922 _from_compiled_entry = adapter()->get_c2i_entry(); 923 } 924 OrderAccess::storestore(); 925 _from_interpreted_entry = _i2i_entry; 926 OrderAccess::storestore(); 927 _code = NULL; 928 } 929 930 #if INCLUDE_CDS 931 // Called by class data sharing to remove any entry points (which are not shared) 932 void Method::unlink_method() { 933 _code = NULL; 934 935 assert(DumpSharedSpaces, "dump time only"); 936 // Set the values to what they should be at run time. Note that 937 // this Method can no longer be executed during dump time. 938 _i2i_entry = Interpreter::entry_for_cds_method(this); 939 _from_interpreted_entry = _i2i_entry; 940 941 if (is_native()) { 942 *native_function_addr() = NULL; 943 set_signature_handler(NULL); 944 } 945 NOT_PRODUCT(set_compiled_invocation_count(0);) 946 947 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter(); 948 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline()); 949 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline(); 950 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time"); 951 952 set_method_data(NULL); 953 clear_method_counters(); 954 } 955 #endif 956 957 /**************************************************************************** 958 // The following illustrates how the entries work for CDS shared Methods: 959 // 960 // Our goal is to delay writing into a shared Method until it's compiled. 961 // Hence, we want to determine the initial values for _i2i_entry, 962 // _from_interpreted_entry and _from_compiled_entry during CDS dump time. 963 // 964 // In this example, both Methods A and B have the _i2i_entry of "zero_locals". 965 // They also have similar signatures so that they will share the same 966 // AdapterHandlerEntry. 967 // 968 // _adapter_trampoline points to a fixed location in the RW section of 969 // the CDS archive. This location initially contains a NULL pointer. When the 970 // first of method A or B is linked, an AdapterHandlerEntry is allocated 971 // dynamically, and its c2i/i2c entries are generated. 972 // 973 // _i2i_entry and _from_interpreted_entry initially points to the same 974 // (fixed) location in the CODE section of the CDS archive. This contains 975 // an unconditional branch to the actual entry for "zero_locals", which is 976 // generated at run time and may be on an arbitrary address. Thus, the 977 // unconditional branch is also generated at run time to jump to the correct 978 // address. 979 // 980 // Similarly, _from_compiled_entry points to a fixed address in the CODE 981 // section. This address has enough space for an unconditional branch 982 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is 983 // initialized, and the address for the actual c2i_entry is known, we emit a 984 // branch instruction here to branch to the actual c2i_entry. 985 // 986 // The effect of the extra branch on the i2i and c2i entries is negligible. 987 // 988 // The reason for putting _adapter_trampoline in RO is many shared Methods 989 // share the same AdapterHandlerEntry, so we can save space in the RW section 990 // by having the extra indirection. 991 992 993 [Method A: RW] 994 _constMethod ----> [ConstMethod: RO] 995 _adapter_trampoline -----------+ 996 | 997 _i2i_entry (same value as method B) | 998 _from_interpreted_entry (same value as method B) | 999 _from_compiled_entry (same value as method B) | 1000 | 1001 | 1002 [Method B: RW] +--------+ 1003 _constMethod ----> [ConstMethod: RO] | 1004 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+ 1005 | 1006 +-------------------------------+ 1007 | 1008 +----> [AdapterHandlerEntry] (allocated at run time) 1009 _fingerprint 1010 _c2i_entry ---------------------------------+->[c2i entry..] 1011 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] | 1012 _from_interpreted_entry | _c2i_unverified_entry | | 1013 | | | | 1014 | | (_cds_entry_table: CODE) | | 1015 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | | 1016 | | (allocated at run time) | | 1017 | | ... [asm code ...] | | 1018 +-[not compiled]-+ [n]: jmp _entry_table[n] | | 1019 | | | 1020 | | | 1021 +-[compiled]-------------------------------------------------------------------+ | 1022 | 1023 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) | 1024 [jmp c2i_entry] ------------------------------------------------------+ 1025 1026 ***/ 1027 1028 // Called when the method_holder is getting linked. Setup entrypoints so the method 1029 // is ready to be called from interpreter, compiler, and vtables. 1030 void Method::link_method(const methodHandle& h_method, TRAPS) { 1031 // If the code cache is full, we may reenter this function for the 1032 // leftover methods that weren't linked. 1033 if (is_shared()) { 1034 address entry = Interpreter::entry_for_cds_method(h_method); 1035 assert(entry != NULL && entry == _i2i_entry, 1036 "should be correctly set during dump time"); 1037 if (adapter() != NULL) { 1038 return; 1039 } 1040 assert(entry == _from_interpreted_entry, 1041 "should be correctly set during dump time"); 1042 } else if (_i2i_entry != NULL) { 1043 return; 1044 } 1045 assert( _code == NULL, "nothing compiled yet" ); 1046 1047 // Setup interpreter entrypoint 1048 assert(this == h_method(), "wrong h_method()" ); 1049 1050 if (!is_shared()) { 1051 assert(adapter() == NULL, "init'd to NULL"); 1052 address entry = Interpreter::entry_for_method(h_method); 1053 assert(entry != NULL, "interpreter entry must be non-null"); 1054 // Sets both _i2i_entry and _from_interpreted_entry 1055 set_interpreter_entry(entry); 1056 } 1057 1058 // Don't overwrite already registered native entries. 1059 if (is_native() && !has_native_function()) { 1060 set_native_function( 1061 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), 1062 !native_bind_event_is_interesting); 1063 } 1064 1065 // Setup compiler entrypoint. This is made eagerly, so we do not need 1066 // special handling of vtables. An alternative is to make adapters more 1067 // lazily by calling make_adapter() from from_compiled_entry() for the 1068 // normal calls. For vtable calls life gets more complicated. When a 1069 // call-site goes mega-morphic we need adapters in all methods which can be 1070 // called from the vtable. We need adapters on such methods that get loaded 1071 // later. Ditto for mega-morphic itable calls. If this proves to be a 1072 // problem we'll make these lazily later. 1073 (void) make_adapters(h_method, CHECK); 1074 1075 // ONLY USE the h_method now as make_adapter may have blocked 1076 1077 } 1078 1079 address Method::make_adapters(const methodHandle& mh, TRAPS) { 1080 // Adapters for compiled code are made eagerly here. They are fairly 1081 // small (generally < 100 bytes) and quick to make (and cached and shared) 1082 // so making them eagerly shouldn't be too expensive. 1083 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh); 1084 if (adapter == NULL ) { 1085 if (!is_init_completed()) { 1086 // Don't throw exceptions during VM initialization because java.lang.* classes 1087 // might not have been initialized, causing problems when constructing the 1088 // Java exception object. 1089 vm_exit_during_initialization("Out of space in CodeCache for adapters"); 1090 } else { 1091 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters"); 1092 } 1093 } 1094 1095 if (mh->is_shared()) { 1096 assert(mh->adapter() == adapter, "must be"); 1097 assert(mh->_from_compiled_entry != NULL, "must be"); 1098 } else { 1099 mh->set_adapter_entry(adapter); 1100 mh->_from_compiled_entry = adapter->get_c2i_entry(); 1101 } 1102 return adapter->get_c2i_entry(); 1103 } 1104 1105 void Method::restore_unshareable_info(TRAPS) { 1106 assert(is_method() && is_valid_method(), "ensure C++ vtable is restored"); 1107 1108 // Since restore_unshareable_info can be called more than once for a method, don't 1109 // redo any work. 1110 if (adapter() == NULL) { 1111 methodHandle mh(THREAD, this); 1112 link_method(mh, CHECK); 1113 } 1114 } 1115 1116 address Method::from_compiled_entry_no_trampoline() const { 1117 CompiledMethod *code = OrderAccess::load_acquire(&_code); 1118 if (code) { 1119 return code->verified_entry_point(); 1120 } else { 1121 return adapter()->get_c2i_entry(); 1122 } 1123 } 1124 1125 // The verified_code_entry() must be called when a invoke is resolved 1126 // on this method. 1127 1128 // It returns the compiled code entry point, after asserting not null. 1129 // This function is called after potential safepoints so that nmethod 1130 // or adapter that it points to is still live and valid. 1131 // This function must not hit a safepoint! 1132 address Method::verified_code_entry() { 1133 debug_only(NoSafepointVerifier nsv;) 1134 assert(_from_compiled_entry != NULL, "must be set"); 1135 return _from_compiled_entry; 1136 } 1137 1138 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all 1139 // (could be racing a deopt). 1140 // Not inline to avoid circular ref. 1141 bool Method::check_code() const { 1142 // cached in a register or local. There's a race on the value of the field. 1143 CompiledMethod *code = OrderAccess::load_acquire(&_code); 1144 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method()); 1145 } 1146 1147 // Install compiled code. Instantly it can execute. 1148 void Method::set_code(const methodHandle& mh, CompiledMethod *code) { 1149 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 1150 assert( code, "use clear_code to remove code" ); 1151 assert( mh->check_code(), "" ); 1152 1153 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!"); 1154 1155 // These writes must happen in this order, because the interpreter will 1156 // directly jump to from_interpreted_entry which jumps to an i2c adapter 1157 // which jumps to _from_compiled_entry. 1158 mh->_code = code; // Assign before allowing compiled code to exec 1159 1160 int comp_level = code->comp_level(); 1161 // In theory there could be a race here. In practice it is unlikely 1162 // and not worth worrying about. 1163 if (comp_level > mh->highest_comp_level()) { 1164 mh->set_highest_comp_level(comp_level); 1165 } 1166 1167 OrderAccess::storestore(); 1168 mh->_from_compiled_entry = code->verified_entry_point(); 1169 OrderAccess::storestore(); 1170 // Instantly compiled code can execute. 1171 if (!mh->is_method_handle_intrinsic()) 1172 mh->_from_interpreted_entry = mh->get_i2c_entry(); 1173 } 1174 1175 1176 bool Method::is_overridden_in(Klass* k) const { 1177 InstanceKlass* ik = InstanceKlass::cast(k); 1178 1179 if (ik->is_interface()) return false; 1180 1181 // If method is an interface, we skip it - except if it 1182 // is a miranda method 1183 if (method_holder()->is_interface()) { 1184 // Check that method is not a miranda method 1185 if (ik->lookup_method(name(), signature()) == NULL) { 1186 // No implementation exist - so miranda method 1187 return false; 1188 } 1189 return true; 1190 } 1191 1192 assert(ik->is_subclass_of(method_holder()), "should be subklass"); 1193 if (!has_vtable_index()) { 1194 return false; 1195 } else { 1196 Method* vt_m = ik->method_at_vtable(vtable_index()); 1197 return vt_m != this; 1198 } 1199 } 1200 1201 1202 // give advice about whether this Method* should be cached or not 1203 bool Method::should_not_be_cached() const { 1204 if (is_old()) { 1205 // This method has been redefined. It is either EMCP or obsolete 1206 // and we don't want to cache it because that would pin the method 1207 // down and prevent it from being collectible if and when it 1208 // finishes executing. 1209 return true; 1210 } 1211 1212 // caching this method should be just fine 1213 return false; 1214 } 1215 1216 1217 /** 1218 * Returns true if this is one of the specially treated methods for 1219 * security related stack walks (like Reflection.getCallerClass). 1220 */ 1221 bool Method::is_ignored_by_security_stack_walk() const { 1222 if (intrinsic_id() == vmIntrinsics::_invoke) { 1223 // This is Method.invoke() -- ignore it 1224 return true; 1225 } 1226 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) { 1227 // This is an auxilary frame -- ignore it 1228 return true; 1229 } 1230 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) { 1231 // This is an internal adapter frame for method handles -- ignore it 1232 return true; 1233 } 1234 return false; 1235 } 1236 1237 1238 // Constant pool structure for invoke methods: 1239 enum { 1240 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc. 1241 _imcp_invoke_signature, // utf8: (variable Symbol*) 1242 _imcp_limit 1243 }; 1244 1245 // Test if this method is an MH adapter frame generated by Java code. 1246 // Cf. java/lang/invoke/InvokerBytecodeGenerator 1247 bool Method::is_compiled_lambda_form() const { 1248 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm; 1249 } 1250 1251 // Test if this method is an internal MH primitive method. 1252 bool Method::is_method_handle_intrinsic() const { 1253 vmIntrinsics::ID iid = intrinsic_id(); 1254 return (MethodHandles::is_signature_polymorphic(iid) && 1255 MethodHandles::is_signature_polymorphic_intrinsic(iid)); 1256 } 1257 1258 bool Method::has_member_arg() const { 1259 vmIntrinsics::ID iid = intrinsic_id(); 1260 return (MethodHandles::is_signature_polymorphic(iid) && 1261 MethodHandles::has_member_arg(iid)); 1262 } 1263 1264 // Make an instance of a signature-polymorphic internal MH primitive. 1265 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid, 1266 Symbol* signature, 1267 TRAPS) { 1268 ResourceMark rm; 1269 methodHandle empty; 1270 1271 InstanceKlass* holder = SystemDictionary::MethodHandle_klass(); 1272 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid); 1273 assert(iid == MethodHandles::signature_polymorphic_name_id(name), ""); 1274 if (TraceMethodHandles) { 1275 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string()); 1276 } 1277 1278 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup) 1279 name->increment_refcount(); 1280 signature->increment_refcount(); 1281 1282 int cp_length = _imcp_limit; 1283 ClassLoaderData* loader_data = holder->class_loader_data(); 1284 constantPoolHandle cp; 1285 { 1286 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty)); 1287 cp = constantPoolHandle(THREAD, cp_oop); 1288 } 1289 cp->set_pool_holder(holder); 1290 cp->symbol_at_put(_imcp_invoke_name, name); 1291 cp->symbol_at_put(_imcp_invoke_signature, signature); 1292 cp->set_has_preresolution(); 1293 1294 // decide on access bits: public or not? 1295 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL); 1296 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid); 1297 if (must_be_static) flags_bits |= JVM_ACC_STATIC; 1298 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods"); 1299 1300 methodHandle m; 1301 { 1302 InlineTableSizes sizes; 1303 Method* m_oop = Method::allocate(loader_data, 0, 1304 accessFlags_from(flags_bits), &sizes, 1305 ConstMethod::NORMAL, CHECK_(empty)); 1306 m = methodHandle(THREAD, m_oop); 1307 } 1308 m->set_constants(cp()); 1309 m->set_name_index(_imcp_invoke_name); 1310 m->set_signature_index(_imcp_invoke_signature); 1311 assert(MethodHandles::is_signature_polymorphic_name(m->name()), ""); 1312 assert(m->signature() == signature, ""); 1313 ResultTypeFinder rtf(signature); 1314 m->constMethod()->set_result_type(rtf.type()); 1315 m->compute_size_of_parameters(THREAD); 1316 m->init_intrinsic_id(); 1317 assert(m->is_method_handle_intrinsic(), ""); 1318 #ifdef ASSERT 1319 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print(); 1320 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker"); 1321 assert(m->intrinsic_id() == iid, "correctly predicted iid"); 1322 #endif //ASSERT 1323 1324 // Finally, set up its entry points. 1325 assert(m->can_be_statically_bound(), ""); 1326 m->set_vtable_index(Method::nonvirtual_vtable_index); 1327 m->link_method(m, CHECK_(empty)); 1328 1329 if (TraceMethodHandles && (Verbose || WizardMode)) { 1330 ttyLocker ttyl; 1331 m->print_on(tty); 1332 } 1333 1334 return m; 1335 } 1336 1337 Klass* Method::check_non_bcp_klass(Klass* klass) { 1338 if (klass != NULL && klass->class_loader() != NULL) { 1339 if (klass->is_objArray_klass()) 1340 klass = ObjArrayKlass::cast(klass)->bottom_klass(); 1341 return klass; 1342 } 1343 return NULL; 1344 } 1345 1346 1347 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length, 1348 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) { 1349 // Code below does not work for native methods - they should never get rewritten anyway 1350 assert(!m->is_native(), "cannot rewrite native methods"); 1351 // Allocate new Method* 1352 AccessFlags flags = m->access_flags(); 1353 1354 ConstMethod* cm = m->constMethod(); 1355 int checked_exceptions_len = cm->checked_exceptions_length(); 1356 int localvariable_len = cm->localvariable_table_length(); 1357 int exception_table_len = cm->exception_table_length(); 1358 int method_parameters_len = cm->method_parameters_length(); 1359 int method_annotations_len = cm->method_annotations_length(); 1360 int parameter_annotations_len = cm->parameter_annotations_length(); 1361 int type_annotations_len = cm->type_annotations_length(); 1362 int default_annotations_len = cm->default_annotations_length(); 1363 1364 InlineTableSizes sizes( 1365 localvariable_len, 1366 new_compressed_linenumber_size, 1367 exception_table_len, 1368 checked_exceptions_len, 1369 method_parameters_len, 1370 cm->generic_signature_index(), 1371 method_annotations_len, 1372 parameter_annotations_len, 1373 type_annotations_len, 1374 default_annotations_len, 1375 0); 1376 1377 ClassLoaderData* loader_data = m->method_holder()->class_loader_data(); 1378 Method* newm_oop = Method::allocate(loader_data, 1379 new_code_length, 1380 flags, 1381 &sizes, 1382 m->method_type(), 1383 CHECK_(methodHandle())); 1384 methodHandle newm (THREAD, newm_oop); 1385 1386 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod* 1387 ConstMethod* newcm = newm->constMethod(); 1388 int new_const_method_size = newm->constMethod()->size(); 1389 1390 // This works because the source and target are both Methods. Some compilers 1391 // (e.g., clang) complain that the target vtable pointer will be stomped, 1392 // so cast away newm()'s and m()'s Methodness. 1393 memcpy((void*)newm(), (void*)m(), sizeof(Method)); 1394 1395 // Create shallow copy of ConstMethod. 1396 memcpy(newcm, m->constMethod(), sizeof(ConstMethod)); 1397 1398 // Reset correct method/const method, method size, and parameter info 1399 newm->set_constMethod(newcm); 1400 newm->constMethod()->set_code_size(new_code_length); 1401 newm->constMethod()->set_constMethod_size(new_const_method_size); 1402 assert(newm->code_size() == new_code_length, "check"); 1403 assert(newm->method_parameters_length() == method_parameters_len, "check"); 1404 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check"); 1405 assert(newm->exception_table_length() == exception_table_len, "check"); 1406 assert(newm->localvariable_table_length() == localvariable_len, "check"); 1407 // Copy new byte codes 1408 memcpy(newm->code_base(), new_code, new_code_length); 1409 // Copy line number table 1410 if (new_compressed_linenumber_size > 0) { 1411 memcpy(newm->compressed_linenumber_table(), 1412 new_compressed_linenumber_table, 1413 new_compressed_linenumber_size); 1414 } 1415 // Copy method_parameters 1416 if (method_parameters_len > 0) { 1417 memcpy(newm->method_parameters_start(), 1418 m->method_parameters_start(), 1419 method_parameters_len * sizeof(MethodParametersElement)); 1420 } 1421 // Copy checked_exceptions 1422 if (checked_exceptions_len > 0) { 1423 memcpy(newm->checked_exceptions_start(), 1424 m->checked_exceptions_start(), 1425 checked_exceptions_len * sizeof(CheckedExceptionElement)); 1426 } 1427 // Copy exception table 1428 if (exception_table_len > 0) { 1429 memcpy(newm->exception_table_start(), 1430 m->exception_table_start(), 1431 exception_table_len * sizeof(ExceptionTableElement)); 1432 } 1433 // Copy local variable number table 1434 if (localvariable_len > 0) { 1435 memcpy(newm->localvariable_table_start(), 1436 m->localvariable_table_start(), 1437 localvariable_len * sizeof(LocalVariableTableElement)); 1438 } 1439 // Copy stackmap table 1440 if (m->has_stackmap_table()) { 1441 int code_attribute_length = m->stackmap_data()->length(); 1442 Array<u1>* stackmap_data = 1443 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL); 1444 memcpy((void*)stackmap_data->adr_at(0), 1445 (void*)m->stackmap_data()->adr_at(0), code_attribute_length); 1446 newm->set_stackmap_data(stackmap_data); 1447 } 1448 1449 // copy annotations over to new method 1450 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL); 1451 return newm; 1452 } 1453 1454 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) { 1455 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics 1456 // because we are not loading from core libraries 1457 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar 1458 // which does not use the class default class loader so we check for its loader here 1459 const InstanceKlass* ik = InstanceKlass::cast(holder); 1460 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) { 1461 return vmSymbols::NO_SID; // regardless of name, no intrinsics here 1462 } 1463 1464 // see if the klass name is well-known: 1465 Symbol* klass_name = ik->name(); 1466 return vmSymbols::find_sid(klass_name); 1467 } 1468 1469 void Method::init_intrinsic_id() { 1470 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once"); 1471 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte)); 1472 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size"); 1473 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), ""); 1474 1475 // the klass name is well-known: 1476 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder()); 1477 assert(klass_id != vmSymbols::NO_SID, "caller responsibility"); 1478 1479 // ditto for method and signature: 1480 vmSymbols::SID name_id = vmSymbols::find_sid(name()); 1481 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle) 1482 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle) 1483 && name_id == vmSymbols::NO_SID) { 1484 return; 1485 } 1486 vmSymbols::SID sig_id = vmSymbols::find_sid(signature()); 1487 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle) 1488 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle) 1489 && sig_id == vmSymbols::NO_SID) { 1490 return; 1491 } 1492 jshort flags = access_flags().as_short(); 1493 1494 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags); 1495 if (id != vmIntrinsics::_none) { 1496 set_intrinsic_id(id); 1497 if (id == vmIntrinsics::_Class_cast) { 1498 // Even if the intrinsic is rejected, we want to inline this simple method. 1499 set_force_inline(true); 1500 } 1501 return; 1502 } 1503 1504 // A few slightly irregular cases: 1505 switch (klass_id) { 1506 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath): 1507 // Second chance: check in regular Math. 1508 switch (name_id) { 1509 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name): 1510 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name): 1511 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name): 1512 // pretend it is the corresponding method in the non-strict class: 1513 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math); 1514 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags); 1515 break; 1516 default: 1517 break; 1518 } 1519 break; 1520 1521 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle 1522 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle): 1523 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle): 1524 if (!is_native()) break; 1525 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name()); 1526 if (is_static() != MethodHandles::is_signature_polymorphic_static(id)) 1527 id = vmIntrinsics::_none; 1528 break; 1529 1530 default: 1531 break; 1532 } 1533 1534 if (id != vmIntrinsics::_none) { 1535 // Set up its iid. It is an alias method. 1536 set_intrinsic_id(id); 1537 return; 1538 } 1539 } 1540 1541 // These two methods are static since a GC may move the Method 1542 bool Method::load_signature_classes(const methodHandle& m, TRAPS) { 1543 if (!THREAD->can_call_java()) { 1544 // There is nothing useful this routine can do from within the Compile thread. 1545 // Hopefully, the signature contains only well-known classes. 1546 // We could scan for this and return true/false, but the caller won't care. 1547 return false; 1548 } 1549 bool sig_is_loaded = true; 1550 Handle class_loader(THREAD, m->method_holder()->class_loader()); 1551 Handle protection_domain(THREAD, m->method_holder()->protection_domain()); 1552 ResourceMark rm(THREAD); 1553 Symbol* signature = m->signature(); 1554 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) { 1555 if (ss.is_object()) { 1556 Symbol* sym = ss.as_symbol(CHECK_(false)); 1557 Symbol* name = sym; 1558 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader, 1559 protection_domain, THREAD); 1560 // We are loading classes eagerly. If a ClassNotFoundException or 1561 // a LinkageError was generated, be sure to ignore it. 1562 if (HAS_PENDING_EXCEPTION) { 1563 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) || 1564 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) { 1565 CLEAR_PENDING_EXCEPTION; 1566 } else { 1567 return false; 1568 } 1569 } 1570 if( klass == NULL) { sig_is_loaded = false; } 1571 } 1572 } 1573 return sig_is_loaded; 1574 } 1575 1576 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) { 1577 Handle class_loader(THREAD, m->method_holder()->class_loader()); 1578 Handle protection_domain(THREAD, m->method_holder()->protection_domain()); 1579 ResourceMark rm(THREAD); 1580 Symbol* signature = m->signature(); 1581 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) { 1582 if (ss.type() == T_OBJECT) { 1583 Symbol* name = ss.as_symbol_or_null(); 1584 if (name == NULL) return true; 1585 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD); 1586 if (klass == NULL) return true; 1587 } 1588 } 1589 return false; 1590 } 1591 1592 // Exposed so field engineers can debug VM 1593 void Method::print_short_name(outputStream* st) { 1594 ResourceMark rm; 1595 #ifdef PRODUCT 1596 st->print(" %s::", method_holder()->external_name()); 1597 #else 1598 st->print(" %s::", method_holder()->internal_name()); 1599 #endif 1600 name()->print_symbol_on(st); 1601 if (WizardMode) signature()->print_symbol_on(st); 1602 else if (MethodHandles::is_signature_polymorphic(intrinsic_id())) 1603 MethodHandles::print_as_basic_type_signature_on(st, signature(), true); 1604 } 1605 1606 // Comparer for sorting an object array containing 1607 // Method*s. 1608 static int method_comparator(Method* a, Method* b) { 1609 return a->name()->fast_compare(b->name()); 1610 } 1611 1612 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array 1613 // default_methods also uses this without the ordering for fast find_method 1614 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) { 1615 int length = methods->length(); 1616 if (length > 1) { 1617 { 1618 NoSafepointVerifier nsv; 1619 QuickSort::sort(methods->data(), length, method_comparator, idempotent); 1620 } 1621 // Reset method ordering 1622 if (set_idnums) { 1623 for (int i = 0; i < length; i++) { 1624 Method* m = methods->at(i); 1625 m->set_method_idnum(i); 1626 m->set_orig_method_idnum(i); 1627 } 1628 } 1629 } 1630 } 1631 1632 //----------------------------------------------------------------------------------- 1633 // Non-product code unless JVM/TI needs it 1634 1635 #if !defined(PRODUCT) || INCLUDE_JVMTI 1636 class SignatureTypePrinter : public SignatureTypeNames { 1637 private: 1638 outputStream* _st; 1639 bool _use_separator; 1640 1641 void type_name(const char* name) { 1642 if (_use_separator) _st->print(", "); 1643 _st->print("%s", name); 1644 _use_separator = true; 1645 } 1646 1647 public: 1648 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) { 1649 _st = st; 1650 _use_separator = false; 1651 } 1652 1653 void print_parameters() { _use_separator = false; iterate_parameters(); } 1654 void print_returntype() { _use_separator = false; iterate_returntype(); } 1655 }; 1656 1657 1658 void Method::print_name(outputStream* st) { 1659 Thread *thread = Thread::current(); 1660 ResourceMark rm(thread); 1661 st->print("%s ", is_static() ? "static" : "virtual"); 1662 if (WizardMode) { 1663 st->print("%s.", method_holder()->internal_name()); 1664 name()->print_symbol_on(st); 1665 signature()->print_symbol_on(st); 1666 } else { 1667 SignatureTypePrinter sig(signature(), st); 1668 sig.print_returntype(); 1669 st->print(" %s.", method_holder()->internal_name()); 1670 name()->print_symbol_on(st); 1671 st->print("("); 1672 sig.print_parameters(); 1673 st->print(")"); 1674 } 1675 } 1676 #endif // !PRODUCT || INCLUDE_JVMTI 1677 1678 1679 void Method::print_codes_on(outputStream* st) const { 1680 print_codes_on(0, code_size(), st); 1681 } 1682 1683 void Method::print_codes_on(int from, int to, outputStream* st) const { 1684 Thread *thread = Thread::current(); 1685 ResourceMark rm(thread); 1686 methodHandle mh (thread, (Method*)this); 1687 BytecodeStream s(mh); 1688 s.set_interval(from, to); 1689 BytecodeTracer::set_closure(BytecodeTracer::std_closure()); 1690 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st); 1691 } 1692 1693 1694 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas 1695 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned) 1696 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used 1697 // as end-of-stream terminator. 1698 1699 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) { 1700 // bci and line number does not compress into single byte. 1701 // Write out escape character and use regular compression for bci and line number. 1702 write_byte((jubyte)0xFF); 1703 write_signed_int(bci_delta); 1704 write_signed_int(line_delta); 1705 } 1706 1707 // See comment in method.hpp which explains why this exists. 1708 #if defined(_M_AMD64) && _MSC_VER >= 1400 1709 #pragma optimize("", off) 1710 void CompressedLineNumberWriteStream::write_pair(int bci, int line) { 1711 write_pair_inline(bci, line); 1712 } 1713 #pragma optimize("", on) 1714 #endif 1715 1716 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) { 1717 _bci = 0; 1718 _line = 0; 1719 }; 1720 1721 1722 bool CompressedLineNumberReadStream::read_pair() { 1723 jubyte next = read_byte(); 1724 // Check for terminator 1725 if (next == 0) return false; 1726 if (next == 0xFF) { 1727 // Escape character, regular compression used 1728 _bci += read_signed_int(); 1729 _line += read_signed_int(); 1730 } else { 1731 // Single byte compression used 1732 _bci += next >> 3; 1733 _line += next & 0x7; 1734 } 1735 return true; 1736 } 1737 1738 #if INCLUDE_JVMTI 1739 1740 Bytecodes::Code Method::orig_bytecode_at(int bci) const { 1741 BreakpointInfo* bp = method_holder()->breakpoints(); 1742 for (; bp != NULL; bp = bp->next()) { 1743 if (bp->match(this, bci)) { 1744 return bp->orig_bytecode(); 1745 } 1746 } 1747 { 1748 ResourceMark rm; 1749 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci); 1750 } 1751 return Bytecodes::_shouldnotreachhere; 1752 } 1753 1754 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) { 1755 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way"); 1756 BreakpointInfo* bp = method_holder()->breakpoints(); 1757 for (; bp != NULL; bp = bp->next()) { 1758 if (bp->match(this, bci)) { 1759 bp->set_orig_bytecode(code); 1760 // and continue, in case there is more than one 1761 } 1762 } 1763 } 1764 1765 void Method::set_breakpoint(int bci) { 1766 InstanceKlass* ik = method_holder(); 1767 BreakpointInfo *bp = new BreakpointInfo(this, bci); 1768 bp->set_next(ik->breakpoints()); 1769 ik->set_breakpoints(bp); 1770 // do this last: 1771 bp->set(this); 1772 } 1773 1774 static void clear_matches(Method* m, int bci) { 1775 InstanceKlass* ik = m->method_holder(); 1776 BreakpointInfo* prev_bp = NULL; 1777 BreakpointInfo* next_bp; 1778 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) { 1779 next_bp = bp->next(); 1780 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint). 1781 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) { 1782 // do this first: 1783 bp->clear(m); 1784 // unhook it 1785 if (prev_bp != NULL) 1786 prev_bp->set_next(next_bp); 1787 else 1788 ik->set_breakpoints(next_bp); 1789 delete bp; 1790 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods 1791 // at same location. So we have multiple matching (method_index and bci) 1792 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one 1793 // breakpoint for clear_breakpoint request and keep all other method versions 1794 // BreakpointInfo for future clear_breakpoint request. 1795 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints) 1796 // which is being called when class is unloaded. We delete all the Breakpoint 1797 // information for all versions of method. We may not correctly restore the original 1798 // bytecode in all method versions, but that is ok. Because the class is being unloaded 1799 // so these methods won't be used anymore. 1800 if (bci >= 0) { 1801 break; 1802 } 1803 } else { 1804 // This one is a keeper. 1805 prev_bp = bp; 1806 } 1807 } 1808 } 1809 1810 void Method::clear_breakpoint(int bci) { 1811 assert(bci >= 0, ""); 1812 clear_matches(this, bci); 1813 } 1814 1815 void Method::clear_all_breakpoints() { 1816 clear_matches(this, -1); 1817 } 1818 1819 #endif // INCLUDE_JVMTI 1820 1821 int Method::invocation_count() { 1822 MethodCounters *mcs = method_counters(); 1823 if (TieredCompilation) { 1824 MethodData* const mdo = method_data(); 1825 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) || 1826 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) { 1827 return InvocationCounter::count_limit; 1828 } else { 1829 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) + 1830 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0); 1831 } 1832 } else { 1833 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count(); 1834 } 1835 } 1836 1837 int Method::backedge_count() { 1838 MethodCounters *mcs = method_counters(); 1839 if (TieredCompilation) { 1840 MethodData* const mdo = method_data(); 1841 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) || 1842 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) { 1843 return InvocationCounter::count_limit; 1844 } else { 1845 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) + 1846 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0); 1847 } 1848 } else { 1849 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count(); 1850 } 1851 } 1852 1853 int Method::highest_comp_level() const { 1854 const MethodCounters* mcs = method_counters(); 1855 if (mcs != NULL) { 1856 return mcs->highest_comp_level(); 1857 } else { 1858 return CompLevel_none; 1859 } 1860 } 1861 1862 int Method::highest_osr_comp_level() const { 1863 const MethodCounters* mcs = method_counters(); 1864 if (mcs != NULL) { 1865 return mcs->highest_osr_comp_level(); 1866 } else { 1867 return CompLevel_none; 1868 } 1869 } 1870 1871 void Method::set_highest_comp_level(int level) { 1872 MethodCounters* mcs = method_counters(); 1873 if (mcs != NULL) { 1874 mcs->set_highest_comp_level(level); 1875 } 1876 } 1877 1878 void Method::set_highest_osr_comp_level(int level) { 1879 MethodCounters* mcs = method_counters(); 1880 if (mcs != NULL) { 1881 mcs->set_highest_osr_comp_level(level); 1882 } 1883 } 1884 1885 #if INCLUDE_JVMTI 1886 1887 BreakpointInfo::BreakpointInfo(Method* m, int bci) { 1888 _bci = bci; 1889 _name_index = m->name_index(); 1890 _signature_index = m->signature_index(); 1891 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci); 1892 if (_orig_bytecode == Bytecodes::_breakpoint) 1893 _orig_bytecode = m->orig_bytecode_at(_bci); 1894 _next = NULL; 1895 } 1896 1897 void BreakpointInfo::set(Method* method) { 1898 #ifdef ASSERT 1899 { 1900 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci); 1901 if (code == Bytecodes::_breakpoint) 1902 code = method->orig_bytecode_at(_bci); 1903 assert(orig_bytecode() == code, "original bytecode must be the same"); 1904 } 1905 #endif 1906 Thread *thread = Thread::current(); 1907 *method->bcp_from(_bci) = Bytecodes::_breakpoint; 1908 method->incr_number_of_breakpoints(thread); 1909 SystemDictionary::notice_modification(); 1910 { 1911 // Deoptimize all dependents on this method 1912 HandleMark hm(thread); 1913 methodHandle mh(thread, method); 1914 CodeCache::flush_dependents_on_method(mh); 1915 } 1916 } 1917 1918 void BreakpointInfo::clear(Method* method) { 1919 *method->bcp_from(_bci) = orig_bytecode(); 1920 assert(method->number_of_breakpoints() > 0, "must not go negative"); 1921 method->decr_number_of_breakpoints(Thread::current()); 1922 } 1923 1924 #endif // INCLUDE_JVMTI 1925 1926 // jmethodID handling 1927 1928 // This is a block allocating object, sort of like JNIHandleBlock, only a 1929 // lot simpler. 1930 // It's allocated on the CHeap because once we allocate a jmethodID, we can 1931 // never get rid of it. 1932 1933 static const int min_block_size = 8; 1934 1935 class JNIMethodBlockNode : public CHeapObj<mtClass> { 1936 friend class JNIMethodBlock; 1937 Method** _methods; 1938 int _number_of_methods; 1939 int _top; 1940 JNIMethodBlockNode* _next; 1941 1942 public: 1943 1944 JNIMethodBlockNode(int num_methods = min_block_size); 1945 1946 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); } 1947 1948 void ensure_methods(int num_addl_methods) { 1949 if (_top < _number_of_methods) { 1950 num_addl_methods -= _number_of_methods - _top; 1951 if (num_addl_methods <= 0) { 1952 return; 1953 } 1954 } 1955 if (_next == NULL) { 1956 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size)); 1957 } else { 1958 _next->ensure_methods(num_addl_methods); 1959 } 1960 } 1961 }; 1962 1963 class JNIMethodBlock : public CHeapObj<mtClass> { 1964 JNIMethodBlockNode _head; 1965 JNIMethodBlockNode *_last_free; 1966 public: 1967 static Method* const _free_method; 1968 1969 JNIMethodBlock(int initial_capacity = min_block_size) 1970 : _head(initial_capacity), _last_free(&_head) {} 1971 1972 void ensure_methods(int num_addl_methods) { 1973 _last_free->ensure_methods(num_addl_methods); 1974 } 1975 1976 Method** add_method(Method* m) { 1977 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) { 1978 if (b->_top < b->_number_of_methods) { 1979 // top points to the next free entry. 1980 int i = b->_top; 1981 b->_methods[i] = m; 1982 b->_top++; 1983 _last_free = b; 1984 return &(b->_methods[i]); 1985 } else if (b->_top == b->_number_of_methods) { 1986 // if the next free entry ran off the block see if there's a free entry 1987 for (int i = 0; i < b->_number_of_methods; i++) { 1988 if (b->_methods[i] == _free_method) { 1989 b->_methods[i] = m; 1990 _last_free = b; 1991 return &(b->_methods[i]); 1992 } 1993 } 1994 // Only check each block once for frees. They're very unlikely. 1995 // Increment top past the end of the block. 1996 b->_top++; 1997 } 1998 // need to allocate a next block. 1999 if (b->_next == NULL) { 2000 b->_next = _last_free = new JNIMethodBlockNode(); 2001 } 2002 } 2003 guarantee(false, "Should always allocate a free block"); 2004 return NULL; 2005 } 2006 2007 bool contains(Method** m) { 2008 if (m == NULL) return false; 2009 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) { 2010 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) { 2011 // This is a bit of extra checking, for two reasons. One is 2012 // that contains() deals with pointers that are passed in by 2013 // JNI code, so making sure that the pointer is aligned 2014 // correctly is valuable. The other is that <= and > are 2015 // technically not defined on pointers, so the if guard can 2016 // pass spuriously; no modern compiler is likely to make that 2017 // a problem, though (and if one did, the guard could also 2018 // fail spuriously, which would be bad). 2019 ptrdiff_t idx = m - b->_methods; 2020 if (b->_methods + idx == m) { 2021 return true; 2022 } 2023 } 2024 } 2025 return false; // not found 2026 } 2027 2028 // Doesn't really destroy it, just marks it as free so it can be reused. 2029 void destroy_method(Method** m) { 2030 #ifdef ASSERT 2031 assert(contains(m), "should be a methodID"); 2032 #endif // ASSERT 2033 *m = _free_method; 2034 } 2035 2036 // During class unloading the methods are cleared, which is different 2037 // than freed. 2038 void clear_all_methods() { 2039 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) { 2040 for (int i = 0; i< b->_number_of_methods; i++) { 2041 b->_methods[i] = NULL; 2042 } 2043 } 2044 } 2045 #ifndef PRODUCT 2046 int count_methods() { 2047 // count all allocated methods 2048 int count = 0; 2049 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) { 2050 for (int i = 0; i< b->_number_of_methods; i++) { 2051 if (b->_methods[i] != _free_method) count++; 2052 } 2053 } 2054 return count; 2055 } 2056 #endif // PRODUCT 2057 }; 2058 2059 // Something that can't be mistaken for an address or a markOop 2060 Method* const JNIMethodBlock::_free_method = (Method*)55; 2061 2062 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) { 2063 _number_of_methods = MAX2(num_methods, min_block_size); 2064 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal); 2065 for (int i = 0; i < _number_of_methods; i++) { 2066 _methods[i] = JNIMethodBlock::_free_method; 2067 } 2068 } 2069 2070 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) { 2071 ClassLoaderData* cld = loader_data; 2072 if (!SafepointSynchronize::is_at_safepoint()) { 2073 // Have to add jmethod_ids() to class loader data thread-safely. 2074 // Also have to add the method to the list safely, which the cld lock 2075 // protects as well. 2076 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag); 2077 if (cld->jmethod_ids() == NULL) { 2078 cld->set_jmethod_ids(new JNIMethodBlock(capacity)); 2079 } else { 2080 cld->jmethod_ids()->ensure_methods(capacity); 2081 } 2082 } else { 2083 // At safepoint, we are single threaded and can set this. 2084 if (cld->jmethod_ids() == NULL) { 2085 cld->set_jmethod_ids(new JNIMethodBlock(capacity)); 2086 } else { 2087 cld->jmethod_ids()->ensure_methods(capacity); 2088 } 2089 } 2090 } 2091 2092 // Add a method id to the jmethod_ids 2093 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) { 2094 ClassLoaderData* cld = loader_data; 2095 2096 if (!SafepointSynchronize::is_at_safepoint()) { 2097 // Have to add jmethod_ids() to class loader data thread-safely. 2098 // Also have to add the method to the list safely, which the cld lock 2099 // protects as well. 2100 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag); 2101 if (cld->jmethod_ids() == NULL) { 2102 cld->set_jmethod_ids(new JNIMethodBlock()); 2103 } 2104 // jmethodID is a pointer to Method* 2105 return (jmethodID)cld->jmethod_ids()->add_method(m); 2106 } else { 2107 // At safepoint, we are single threaded and can set this. 2108 if (cld->jmethod_ids() == NULL) { 2109 cld->set_jmethod_ids(new JNIMethodBlock()); 2110 } 2111 // jmethodID is a pointer to Method* 2112 return (jmethodID)cld->jmethod_ids()->add_method(m); 2113 } 2114 } 2115 2116 // Mark a jmethodID as free. This is called when there is a data race in 2117 // InstanceKlass while creating the jmethodID cache. 2118 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) { 2119 ClassLoaderData* cld = loader_data; 2120 Method** ptr = (Method**)m; 2121 assert(cld->jmethod_ids() != NULL, "should have method handles"); 2122 cld->jmethod_ids()->destroy_method(ptr); 2123 } 2124 2125 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) { 2126 // Can't assert the method_holder is the same because the new method has the 2127 // scratch method holder. 2128 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader() 2129 == new_method->method_holder()->class_loader(), 2130 "changing to a different class loader"); 2131 // Just change the method in place, jmethodID pointer doesn't change. 2132 *((Method**)jmid) = new_method; 2133 } 2134 2135 bool Method::is_method_id(jmethodID mid) { 2136 Method* m = resolve_jmethod_id(mid); 2137 assert(m != NULL, "should be called with non-null method"); 2138 InstanceKlass* ik = m->method_holder(); 2139 ClassLoaderData* cld = ik->class_loader_data(); 2140 if (cld->jmethod_ids() == NULL) return false; 2141 return (cld->jmethod_ids()->contains((Method**)mid)); 2142 } 2143 2144 Method* Method::checked_resolve_jmethod_id(jmethodID mid) { 2145 if (mid == NULL) return NULL; 2146 Method* o = resolve_jmethod_id(mid); 2147 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) { 2148 return NULL; 2149 } 2150 return o; 2151 }; 2152 2153 void Method::set_on_stack(const bool value) { 2154 // Set both the method itself and its constant pool. The constant pool 2155 // on stack means some method referring to it is also on the stack. 2156 constants()->set_on_stack(value); 2157 2158 bool already_set = on_stack(); 2159 _access_flags.set_on_stack(value); 2160 if (value && !already_set) { 2161 MetadataOnStackMark::record(this); 2162 } 2163 } 2164 2165 // Called when the class loader is unloaded to make all methods weak. 2166 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) { 2167 loader_data->jmethod_ids()->clear_all_methods(); 2168 } 2169 2170 bool Method::has_method_vptr(const void* ptr) { 2171 Method m; 2172 // This assumes that the vtbl pointer is the first word of a C++ object. 2173 return dereference_vptr(&m) == dereference_vptr(ptr); 2174 } 2175 2176 // Check that this pointer is valid by checking that the vtbl pointer matches 2177 bool Method::is_valid_method() const { 2178 if (this == NULL) { 2179 return false; 2180 } else if ((intptr_t(this) & (wordSize-1)) != 0) { 2181 // Quick sanity check on pointer. 2182 return false; 2183 } else if (is_shared()) { 2184 return MetaspaceShared::is_valid_shared_method(this); 2185 } else if (Metaspace::contains_non_shared(this)) { 2186 return has_method_vptr((const void*)this); 2187 } else { 2188 return false; 2189 } 2190 } 2191 2192 #ifndef PRODUCT 2193 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) { 2194 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods()); 2195 } 2196 #endif // PRODUCT 2197 2198 2199 // Printing 2200 2201 #ifndef PRODUCT 2202 2203 void Method::print_on(outputStream* st) const { 2204 ResourceMark rm; 2205 assert(is_method(), "must be method"); 2206 st->print_cr("%s", internal_name()); 2207 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this)); 2208 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr(); 2209 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants())); 2210 constants()->print_value_on(st); st->cr(); 2211 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr(); 2212 st->print (" - name: "); name()->print_value_on(st); st->cr(); 2213 st->print (" - signature: "); signature()->print_value_on(st); st->cr(); 2214 st->print_cr(" - max stack: %d", max_stack()); 2215 st->print_cr(" - max locals: %d", max_locals()); 2216 st->print_cr(" - size of params: %d", size_of_parameters()); 2217 st->print_cr(" - method size: %d", method_size()); 2218 if (intrinsic_id() != vmIntrinsics::_none) 2219 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id())); 2220 if (highest_comp_level() != CompLevel_none) 2221 st->print_cr(" - highest level: %d", highest_comp_level()); 2222 st->print_cr(" - vtable index: %d", _vtable_index); 2223 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry())); 2224 st->print( " - adapters: "); 2225 AdapterHandlerEntry* a = ((Method*)this)->adapter(); 2226 if (a == NULL) 2227 st->print_cr(INTPTR_FORMAT, p2i(a)); 2228 else 2229 a->print_adapter_on(st); 2230 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry())); 2231 st->print_cr(" - code size: %d", code_size()); 2232 if (code_size() != 0) { 2233 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base())); 2234 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size())); 2235 } 2236 if (method_data() != NULL) { 2237 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data())); 2238 } 2239 st->print_cr(" - checked ex length: %d", checked_exceptions_length()); 2240 if (checked_exceptions_length() > 0) { 2241 CheckedExceptionElement* table = checked_exceptions_start(); 2242 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table)); 2243 if (Verbose) { 2244 for (int i = 0; i < checked_exceptions_length(); i++) { 2245 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index)); 2246 } 2247 } 2248 } 2249 if (has_linenumber_table()) { 2250 u_char* table = compressed_linenumber_table(); 2251 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table)); 2252 if (Verbose) { 2253 CompressedLineNumberReadStream stream(table); 2254 while (stream.read_pair()) { 2255 st->print_cr(" - line %d: %d", stream.line(), stream.bci()); 2256 } 2257 } 2258 } 2259 st->print_cr(" - localvar length: %d", localvariable_table_length()); 2260 if (localvariable_table_length() > 0) { 2261 LocalVariableTableElement* table = localvariable_table_start(); 2262 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table)); 2263 if (Verbose) { 2264 for (int i = 0; i < localvariable_table_length(); i++) { 2265 int bci = table[i].start_bci; 2266 int len = table[i].length; 2267 const char* name = constants()->printable_name_at(table[i].name_cp_index); 2268 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index); 2269 int slot = table[i].slot; 2270 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot); 2271 } 2272 } 2273 } 2274 if (code() != NULL) { 2275 st->print (" - compiled code: "); 2276 code()->print_value_on(st); 2277 } 2278 if (is_native()) { 2279 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function())); 2280 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler())); 2281 } 2282 } 2283 2284 void Method::print_linkage_flags(outputStream* st) { 2285 access_flags().print_on(st); 2286 if (is_default_method()) { 2287 st->print("default "); 2288 } 2289 if (is_overpass()) { 2290 st->print("overpass "); 2291 } 2292 } 2293 #endif //PRODUCT 2294 2295 void Method::print_value_on(outputStream* st) const { 2296 assert(is_method(), "must be method"); 2297 st->print("%s", internal_name()); 2298 print_address_on(st); 2299 st->print(" "); 2300 name()->print_value_on(st); 2301 st->print(" "); 2302 signature()->print_value_on(st); 2303 st->print(" in "); 2304 method_holder()->print_value_on(st); 2305 if (WizardMode) st->print("#%d", _vtable_index); 2306 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals()); 2307 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code()); 2308 } 2309 2310 #if INCLUDE_SERVICES 2311 // Size Statistics 2312 void Method::collect_statistics(KlassSizeStats *sz) const { 2313 int mysize = sz->count(this); 2314 sz->_method_bytes += mysize; 2315 sz->_method_all_bytes += mysize; 2316 sz->_rw_bytes += mysize; 2317 2318 if (constMethod()) { 2319 constMethod()->collect_statistics(sz); 2320 } 2321 if (method_data()) { 2322 method_data()->collect_statistics(sz); 2323 } 2324 } 2325 #endif // INCLUDE_SERVICES 2326 2327 // LogTouchedMethods and PrintTouchedMethods 2328 2329 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because 2330 // the Method may be garbage collected. Let's roll our own hash table. 2331 class TouchedMethodRecord : CHeapObj<mtTracing> { 2332 public: 2333 // It's OK to store Symbols here because they will NOT be GC'ed if 2334 // LogTouchedMethods is enabled. 2335 TouchedMethodRecord* _next; 2336 Symbol* _class_name; 2337 Symbol* _method_name; 2338 Symbol* _method_signature; 2339 }; 2340 2341 static const int TOUCHED_METHOD_TABLE_SIZE = 20011; 2342 static TouchedMethodRecord** _touched_method_table = NULL; 2343 2344 void Method::log_touched(TRAPS) { 2345 2346 const int table_size = TOUCHED_METHOD_TABLE_SIZE; 2347 Symbol* my_class = klass_name(); 2348 Symbol* my_name = name(); 2349 Symbol* my_sig = signature(); 2350 2351 unsigned int hash = my_class->identity_hash() + 2352 my_name->identity_hash() + 2353 my_sig->identity_hash(); 2354 juint index = juint(hash) % table_size; 2355 2356 MutexLocker ml(TouchedMethodLog_lock, THREAD); 2357 if (_touched_method_table == NULL) { 2358 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size, 2359 mtTracing, CURRENT_PC); 2360 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size); 2361 } 2362 2363 TouchedMethodRecord* ptr = _touched_method_table[index]; 2364 while (ptr) { 2365 if (ptr->_class_name == my_class && 2366 ptr->_method_name == my_name && 2367 ptr->_method_signature == my_sig) { 2368 return; 2369 } 2370 if (ptr->_next == NULL) break; 2371 ptr = ptr->_next; 2372 } 2373 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing); 2374 my_class->set_permanent(); // prevent reclaimed by GC 2375 my_name->set_permanent(); 2376 my_sig->set_permanent(); 2377 nptr->_class_name = my_class; 2378 nptr->_method_name = my_name; 2379 nptr->_method_signature = my_sig; 2380 nptr->_next = NULL; 2381 2382 if (ptr == NULL) { 2383 // first 2384 _touched_method_table[index] = nptr; 2385 } else { 2386 ptr->_next = nptr; 2387 } 2388 } 2389 2390 void Method::print_touched_methods(outputStream* out) { 2391 MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock); 2392 out->print_cr("# Method::print_touched_methods version 1"); 2393 if (_touched_method_table) { 2394 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) { 2395 TouchedMethodRecord* ptr = _touched_method_table[i]; 2396 while(ptr) { 2397 ptr->_class_name->print_symbol_on(out); out->print("."); 2398 ptr->_method_name->print_symbol_on(out); out->print(":"); 2399 ptr->_method_signature->print_symbol_on(out); out->cr(); 2400 ptr = ptr->_next; 2401 } 2402 } 2403 } 2404 } 2405 2406 // Verification 2407 2408 void Method::verify_on(outputStream* st) { 2409 guarantee(is_method(), "object must be method"); 2410 guarantee(constants()->is_constantPool(), "should be constant pool"); 2411 guarantee(constMethod()->is_constMethod(), "should be ConstMethod*"); 2412 MethodData* md = method_data(); 2413 guarantee(md == NULL || 2414 md->is_methodData(), "should be method data"); 2415 }