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/allocation.inline.hpp" 39 #include "memory/heapInspection.hpp" 40 #include "memory/metadataFactory.hpp" 41 #include "memory/metaspaceClosure.hpp" 42 #include "memory/metaspaceShared.hpp" 43 #include "memory/oopFactory.hpp" 44 #include "memory/resourceArea.hpp" 45 #include "oops/constMethod.hpp" 46 #include "oops/method.inline.hpp" 47 #include "oops/methodData.hpp" 48 #include "oops/objArrayOop.inline.hpp" 49 #include "oops/oop.inline.hpp" 50 #include "oops/symbol.hpp" 51 #include "prims/jvmtiExport.hpp" 52 #include "prims/methodHandles.hpp" 53 #include "prims/nativeLookup.hpp" 54 #include "runtime/arguments.hpp" 55 #include "runtime/compilationPolicy.hpp" 56 #include "runtime/frame.inline.hpp" 57 #include "runtime/handles.inline.hpp" 58 #include "runtime/init.hpp" 59 #include "runtime/orderAccess.inline.hpp" 60 #include "runtime/relocator.hpp" 61 #include "runtime/sharedRuntime.hpp" 62 #include "runtime/signature.hpp" 63 #include "utilities/align.hpp" 64 #include "utilities/quickSort.hpp" 65 #include "utilities/vmError.hpp" 66 #include "utilities/xmlstream.hpp" 67 68 // Implementation of Method 69 70 Method* Method::allocate(ClassLoaderData* loader_data, 71 int byte_code_size, 72 AccessFlags access_flags, 73 InlineTableSizes* sizes, 74 ConstMethod::MethodType method_type, 75 TRAPS) { 76 assert(!access_flags.is_native() || byte_code_size == 0, 77 "native methods should not contain byte codes"); 78 ConstMethod* cm = ConstMethod::allocate(loader_data, 79 byte_code_size, 80 sizes, 81 method_type, 82 CHECK_NULL); 83 int size = Method::size(access_flags.is_native()); 84 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags); 85 } 86 87 Method::Method(ConstMethod* xconst, AccessFlags access_flags) { 88 NoSafepointVerifier no_safepoint; 89 set_constMethod(xconst); 90 set_access_flags(access_flags); 91 set_intrinsic_id(vmIntrinsics::_none); 92 set_force_inline(false); 93 set_hidden(false); 94 set_dont_inline(false); 95 set_has_injected_profile(false); 96 set_method_data(NULL); 97 clear_method_counters(); 98 set_vtable_index(Method::garbage_vtable_index); 99 100 // Fix and bury in Method* 101 set_interpreter_entry(NULL); // sets i2i entry and from_int 102 set_adapter_entry(NULL); 103 clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i 104 105 if (access_flags.is_native()) { 106 clear_native_function(); 107 set_signature_handler(NULL); 108 } 109 110 NOT_PRODUCT(set_compiled_invocation_count(0);) 111 } 112 113 // Release Method*. The nmethod will be gone when we get here because 114 // we've walked the code cache. 115 void Method::deallocate_contents(ClassLoaderData* loader_data) { 116 MetadataFactory::free_metadata(loader_data, constMethod()); 117 set_constMethod(NULL); 118 MetadataFactory::free_metadata(loader_data, method_data()); 119 set_method_data(NULL); 120 MetadataFactory::free_metadata(loader_data, method_counters()); 121 clear_method_counters(); 122 // The nmethod will be gone when we get here. 123 if (code() != NULL) _code = NULL; 124 } 125 126 address Method::get_i2c_entry() { 127 assert(adapter() != NULL, "must have"); 128 return adapter()->get_i2c_entry(); 129 } 130 131 address Method::get_c2i_entry() { 132 assert(adapter() != NULL, "must have"); 133 return adapter()->get_c2i_entry(); 134 } 135 136 address Method::get_c2i_unverified_entry() { 137 assert(adapter() != NULL, "must have"); 138 return adapter()->get_c2i_unverified_entry(); 139 } 140 141 char* Method::name_and_sig_as_C_string() const { 142 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature()); 143 } 144 145 char* Method::name_and_sig_as_C_string(char* buf, int size) const { 146 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size); 147 } 148 149 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) { 150 const char* klass_name = klass->external_name(); 151 int klass_name_len = (int)strlen(klass_name); 152 int method_name_len = method_name->utf8_length(); 153 int len = klass_name_len + 1 + method_name_len + signature->utf8_length(); 154 char* dest = NEW_RESOURCE_ARRAY(char, len + 1); 155 strcpy(dest, klass_name); 156 dest[klass_name_len] = '.'; 157 strcpy(&dest[klass_name_len + 1], method_name->as_C_string()); 158 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string()); 159 dest[len] = 0; 160 return dest; 161 } 162 163 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) { 164 Symbol* klass_name = klass->name(); 165 klass_name->as_klass_external_name(buf, size); 166 int len = (int)strlen(buf); 167 168 if (len < size - 1) { 169 buf[len++] = '.'; 170 171 method_name->as_C_string(&(buf[len]), size - len); 172 len = (int)strlen(buf); 173 174 signature->as_C_string(&(buf[len]), size - len); 175 } 176 177 return buf; 178 } 179 180 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) { 181 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index) 182 // access exception table 183 ExceptionTable table(mh()); 184 int length = table.length(); 185 // iterate through all entries sequentially 186 constantPoolHandle pool(THREAD, mh->constants()); 187 for (int i = 0; i < length; i ++) { 188 //reacquire the table in case a GC happened 189 ExceptionTable table(mh()); 190 int beg_bci = table.start_pc(i); 191 int end_bci = table.end_pc(i); 192 assert(beg_bci <= end_bci, "inconsistent exception table"); 193 if (beg_bci <= throw_bci && throw_bci < end_bci) { 194 // exception handler bci range covers throw_bci => investigate further 195 int handler_bci = table.handler_pc(i); 196 int klass_index = table.catch_type_index(i); 197 if (klass_index == 0) { 198 return handler_bci; 199 } else if (ex_klass == NULL) { 200 return handler_bci; 201 } else { 202 // we know the exception class => get the constraint class 203 // this may require loading of the constraint class; if verification 204 // fails or some other exception occurs, return handler_bci 205 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci)); 206 assert(k != NULL, "klass not loaded"); 207 if (ex_klass->is_subtype_of(k)) { 208 return handler_bci; 209 } 210 } 211 } 212 } 213 214 return -1; 215 } 216 217 void Method::mask_for(int bci, InterpreterOopMap* mask) { 218 methodHandle h_this(Thread::current(), this); 219 // Only GC uses the OopMapCache during thread stack root scanning 220 // any other uses generate an oopmap but do not save it in the cache. 221 if (Universe::heap()->is_gc_active()) { 222 method_holder()->mask_for(h_this, bci, mask); 223 } else { 224 OopMapCache::compute_one_oop_map(h_this, bci, mask); 225 } 226 return; 227 } 228 229 230 int Method::bci_from(address bcp) const { 231 if (is_native() && bcp == 0) { 232 return 0; 233 } 234 #ifdef ASSERT 235 { 236 ResourceMark rm; 237 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(), 238 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s", 239 p2i(bcp), name_and_sig_as_C_string()); 240 } 241 #endif 242 return bcp - code_base(); 243 } 244 245 246 int Method::validate_bci(int bci) const { 247 return (bci == 0 || bci < code_size()) ? bci : -1; 248 } 249 250 // Return bci if it appears to be a valid bcp 251 // Return -1 otherwise. 252 // Used by profiling code, when invalid data is a possibility. 253 // The caller is responsible for validating the Method* itself. 254 int Method::validate_bci_from_bcp(address bcp) const { 255 // keep bci as -1 if not a valid bci 256 int bci = -1; 257 if (bcp == 0 || bcp == code_base()) { 258 // code_size() may return 0 and we allow 0 here 259 // the method may be native 260 bci = 0; 261 } else if (contains(bcp)) { 262 bci = bcp - code_base(); 263 } 264 // Assert that if we have dodged any asserts, bci is negative. 265 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0"); 266 return bci; 267 } 268 269 address Method::bcp_from(int bci) const { 270 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()), 271 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native"); 272 address bcp = code_base() + bci; 273 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method"); 274 return bcp; 275 } 276 277 address Method::bcp_from(address bcp) const { 278 if (is_native() && bcp == NULL) { 279 return code_base(); 280 } else { 281 return bcp; 282 } 283 } 284 285 int Method::size(bool is_native) { 286 // If native, then include pointers for native_function and signature_handler 287 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0; 288 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord; 289 return align_metadata_size(header_size() + extra_words); 290 } 291 292 293 Symbol* Method::klass_name() const { 294 return method_holder()->name(); 295 } 296 297 298 void Method::metaspace_pointers_do(MetaspaceClosure* it) { 299 log_trace(cds)("Iter(Method): %p", this); 300 301 it->push(&_constMethod); 302 it->push(&_method_data); 303 it->push(&_method_counters); 304 } 305 306 // Attempt to return method oop to original state. Clear any pointers 307 // (to objects outside the shared spaces). We won't be able to predict 308 // where they should point in a new JVM. Further initialize some 309 // entries now in order allow them to be write protected later. 310 311 void Method::remove_unshareable_info() { 312 unlink_method(); 313 } 314 315 void Method::set_vtable_index(int index) { 316 if (is_shared() && !MetaspaceShared::remapped_readwrite()) { 317 // At runtime initialize_vtable is rerun as part of link_class_impl() 318 // for a shared class loaded by the non-boot loader to obtain the loader 319 // constraints based on the runtime classloaders' context. 320 return; // don't write into the shared class 321 } else { 322 _vtable_index = index; 323 } 324 } 325 326 void Method::set_itable_index(int index) { 327 if (is_shared() && !MetaspaceShared::remapped_readwrite()) { 328 // At runtime initialize_itable is rerun as part of link_class_impl() 329 // for a shared class loaded by the non-boot loader to obtain the loader 330 // constraints based on the runtime classloaders' context. The dumptime 331 // itable index should be the same as the runtime index. 332 assert(_vtable_index == itable_index_max - index, 333 "archived itable index is different from runtime index"); 334 return; // don’t write into the shared class 335 } else { 336 _vtable_index = itable_index_max - index; 337 } 338 assert(valid_itable_index(), ""); 339 } 340 341 342 343 bool Method::was_executed_more_than(int n) { 344 // Invocation counter is reset when the Method* is compiled. 345 // If the method has compiled code we therefore assume it has 346 // be excuted more than n times. 347 if (is_accessor() || is_empty_method() || (code() != NULL)) { 348 // interpreter doesn't bump invocation counter of trivial methods 349 // compiler does not bump invocation counter of compiled methods 350 return true; 351 } 352 else if ((method_counters() != NULL && 353 method_counters()->invocation_counter()->carry()) || 354 (method_data() != NULL && 355 method_data()->invocation_counter()->carry())) { 356 // The carry bit is set when the counter overflows and causes 357 // a compilation to occur. We don't know how many times 358 // the counter has been reset, so we simply assume it has 359 // been executed more than n times. 360 return true; 361 } else { 362 return invocation_count() > n; 363 } 364 } 365 366 void Method::print_invocation_count() { 367 if (is_static()) tty->print("static "); 368 if (is_final()) tty->print("final "); 369 if (is_synchronized()) tty->print("synchronized "); 370 if (is_native()) tty->print("native "); 371 tty->print("%s::", method_holder()->external_name()); 372 name()->print_symbol_on(tty); 373 signature()->print_symbol_on(tty); 374 375 if (WizardMode) { 376 // dump the size of the byte codes 377 tty->print(" {%d}", code_size()); 378 } 379 tty->cr(); 380 381 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count()); 382 tty->print_cr (" invocation_counter: %8d ", invocation_count()); 383 tty->print_cr (" backedge_counter: %8d ", backedge_count()); 384 #ifndef PRODUCT 385 if (CountCompiledCalls) { 386 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count()); 387 } 388 #endif 389 } 390 391 // Build a MethodData* object to hold information about this method 392 // collected in the interpreter. 393 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) { 394 // Do not profile the method if metaspace has hit an OOM previously 395 // allocating profiling data. Callers clear pending exception so don't 396 // add one here. 397 if (ClassLoaderDataGraph::has_metaspace_oom()) { 398 return; 399 } 400 401 // Grab a lock here to prevent multiple 402 // MethodData*s from being created. 403 MutexLocker ml(MethodData_lock, THREAD); 404 if (method->method_data() == NULL) { 405 ClassLoaderData* loader_data = method->method_holder()->class_loader_data(); 406 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD); 407 if (HAS_PENDING_EXCEPTION) { 408 CompileBroker::log_metaspace_failure(); 409 ClassLoaderDataGraph::set_metaspace_oom(true); 410 return; // return the exception (which is cleared) 411 } 412 413 method->set_method_data(method_data); 414 if (PrintMethodData && (Verbose || WizardMode)) { 415 ResourceMark rm(THREAD); 416 tty->print("build_interpreter_method_data for "); 417 method->print_name(tty); 418 tty->cr(); 419 // At the end of the run, the MDO, full of data, will be dumped. 420 } 421 } 422 } 423 424 MethodCounters* Method::build_method_counters(Method* m, TRAPS) { 425 // Do not profile the method if metaspace has hit an OOM previously 426 if (ClassLoaderDataGraph::has_metaspace_oom()) { 427 return NULL; 428 } 429 430 methodHandle mh(m); 431 MethodCounters* counters = MethodCounters::allocate(mh, THREAD); 432 if (HAS_PENDING_EXCEPTION) { 433 CompileBroker::log_metaspace_failure(); 434 ClassLoaderDataGraph::set_metaspace_oom(true); 435 return NULL; // return the exception (which is cleared) 436 } 437 if (!mh->init_method_counters(counters)) { 438 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters); 439 } 440 441 if (LogTouchedMethods) { 442 mh->log_touched(CHECK_NULL); 443 } 444 445 return mh->method_counters(); 446 } 447 448 bool Method::init_method_counters(MethodCounters* counters) { 449 // Try to install a pointer to MethodCounters, return true on success. 450 return Atomic::replace_if_null(counters, &_method_counters); 451 } 452 453 void Method::cleanup_inline_caches() { 454 // The current system doesn't use inline caches in the interpreter 455 // => nothing to do (keep this method around for future use) 456 } 457 458 459 int Method::extra_stack_words() { 460 // not an inline function, to avoid a header dependency on Interpreter 461 return extra_stack_entries() * Interpreter::stackElementSize; 462 } 463 464 465 void Method::compute_size_of_parameters(Thread *thread) { 466 ArgumentSizeComputer asc(signature()); 467 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1)); 468 } 469 470 BasicType Method::result_type() const { 471 ResultTypeFinder rtf(signature()); 472 return rtf.type(); 473 } 474 475 476 bool Method::is_empty_method() const { 477 return code_size() == 1 478 && *code_base() == Bytecodes::_return; 479 } 480 481 482 bool Method::is_vanilla_constructor() const { 483 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method 484 // which only calls the superclass vanilla constructor and possibly does stores of 485 // zero constants to local fields: 486 // 487 // aload_0 488 // invokespecial 489 // indexbyte1 490 // indexbyte2 491 // 492 // followed by an (optional) sequence of: 493 // 494 // aload_0 495 // aconst_null / iconst_0 / fconst_0 / dconst_0 496 // putfield 497 // indexbyte1 498 // indexbyte2 499 // 500 // followed by: 501 // 502 // return 503 504 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors"); 505 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors"); 506 int size = code_size(); 507 // Check if size match 508 if (size == 0 || size % 5 != 0) return false; 509 address cb = code_base(); 510 int last = size - 1; 511 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) { 512 // Does not call superclass default constructor 513 return false; 514 } 515 // Check optional sequence 516 for (int i = 4; i < last; i += 5) { 517 if (cb[i] != Bytecodes::_aload_0) return false; 518 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false; 519 if (cb[i+2] != Bytecodes::_putfield) return false; 520 } 521 return true; 522 } 523 524 525 bool Method::compute_has_loops_flag() { 526 BytecodeStream bcs(this); 527 Bytecodes::Code bc; 528 529 while ((bc = bcs.next()) >= 0) { 530 switch( bc ) { 531 case Bytecodes::_ifeq: 532 case Bytecodes::_ifnull: 533 case Bytecodes::_iflt: 534 case Bytecodes::_ifle: 535 case Bytecodes::_ifne: 536 case Bytecodes::_ifnonnull: 537 case Bytecodes::_ifgt: 538 case Bytecodes::_ifge: 539 case Bytecodes::_if_icmpeq: 540 case Bytecodes::_if_icmpne: 541 case Bytecodes::_if_icmplt: 542 case Bytecodes::_if_icmpgt: 543 case Bytecodes::_if_icmple: 544 case Bytecodes::_if_icmpge: 545 case Bytecodes::_if_acmpeq: 546 case Bytecodes::_if_acmpne: 547 case Bytecodes::_goto: 548 case Bytecodes::_jsr: 549 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops(); 550 break; 551 552 case Bytecodes::_goto_w: 553 case Bytecodes::_jsr_w: 554 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops(); 555 break; 556 557 default: 558 break; 559 } 560 } 561 _access_flags.set_loops_flag_init(); 562 return _access_flags.has_loops(); 563 } 564 565 bool Method::is_final_method(AccessFlags class_access_flags) const { 566 // or "does_not_require_vtable_entry" 567 // default method or overpass can occur, is not final (reuses vtable entry) 568 // private methods in classes get vtable entries for backward class compatibility. 569 if (is_overpass() || is_default_method()) return false; 570 return is_final() || class_access_flags.is_final(); 571 } 572 573 bool Method::is_final_method() const { 574 return is_final_method(method_holder()->access_flags()); 575 } 576 577 bool Method::is_default_method() const { 578 if (method_holder() != NULL && 579 method_holder()->is_interface() && 580 !is_abstract() && !is_private()) { 581 return true; 582 } else { 583 return false; 584 } 585 } 586 587 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const { 588 if (is_final_method(class_access_flags)) return true; 589 #ifdef ASSERT 590 ResourceMark rm; 591 bool is_nonv = (vtable_index() == nonvirtual_vtable_index); 592 if (class_access_flags.is_interface()) { 593 assert(is_nonv == is_static() || is_nonv == is_private(), 594 "nonvirtual unexpected for non-static, non-private: %s", 595 name_and_sig_as_C_string()); 596 } 597 #endif 598 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question"); 599 return vtable_index() == nonvirtual_vtable_index; 600 } 601 602 bool Method::can_be_statically_bound() const { 603 return can_be_statically_bound(method_holder()->access_flags()); 604 } 605 606 bool Method::is_accessor() const { 607 return is_getter() || is_setter(); 608 } 609 610 bool Method::is_getter() const { 611 if (code_size() != 5) return false; 612 if (size_of_parameters() != 1) return false; 613 if (java_code_at(0) != Bytecodes::_aload_0) return false; 614 if (java_code_at(1) != Bytecodes::_getfield) return false; 615 switch (java_code_at(4)) { 616 case Bytecodes::_ireturn: 617 case Bytecodes::_lreturn: 618 case Bytecodes::_freturn: 619 case Bytecodes::_dreturn: 620 case Bytecodes::_areturn: 621 break; 622 default: 623 return false; 624 } 625 return true; 626 } 627 628 bool Method::is_setter() const { 629 if (code_size() != 6) return false; 630 if (java_code_at(0) != Bytecodes::_aload_0) return false; 631 switch (java_code_at(1)) { 632 case Bytecodes::_iload_1: 633 case Bytecodes::_aload_1: 634 case Bytecodes::_fload_1: 635 if (size_of_parameters() != 2) return false; 636 break; 637 case Bytecodes::_dload_1: 638 case Bytecodes::_lload_1: 639 if (size_of_parameters() != 3) return false; 640 break; 641 default: 642 return false; 643 } 644 if (java_code_at(2) != Bytecodes::_putfield) return false; 645 if (java_code_at(5) != Bytecodes::_return) return false; 646 return true; 647 } 648 649 bool Method::is_constant_getter() const { 650 int last_index = code_size() - 1; 651 // Check if the first 1-3 bytecodes are a constant push 652 // and the last bytecode is a return. 653 return (2 <= code_size() && code_size() <= 4 && 654 Bytecodes::is_const(java_code_at(0)) && 655 Bytecodes::length_for(java_code_at(0)) == last_index && 656 Bytecodes::is_return(java_code_at(last_index))); 657 } 658 659 bool Method::is_initializer() const { 660 return is_object_initializer() || is_static_initializer(); 661 } 662 663 bool Method::has_valid_initializer_flags() const { 664 return (is_static() || 665 method_holder()->major_version() < 51); 666 } 667 668 bool Method::is_static_initializer() const { 669 // For classfiles version 51 or greater, ensure that the clinit method is 670 // static. Non-static methods with the name "<clinit>" are not static 671 // initializers. (older classfiles exempted for backward compatibility) 672 return name() == vmSymbols::class_initializer_name() && 673 has_valid_initializer_flags(); 674 } 675 676 bool Method::is_object_initializer() const { 677 return name() == vmSymbols::object_initializer_name(); 678 } 679 680 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) { 681 int length = method->checked_exceptions_length(); 682 if (length == 0) { // common case 683 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array()); 684 } else { 685 methodHandle h_this(THREAD, method); 686 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle())); 687 objArrayHandle mirrors (THREAD, m_oop); 688 for (int i = 0; i < length; i++) { 689 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe 690 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle())); 691 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class"); 692 mirrors->obj_at_put(i, k->java_mirror()); 693 } 694 return mirrors; 695 } 696 }; 697 698 699 int Method::line_number_from_bci(int bci) const { 700 if (bci == SynchronizationEntryBCI) bci = 0; 701 assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci"); 702 int best_bci = 0; 703 int best_line = -1; 704 705 if (has_linenumber_table()) { 706 // The line numbers are a short array of 2-tuples [start_pc, line_number]. 707 // Not necessarily sorted and not necessarily one-to-one. 708 CompressedLineNumberReadStream stream(compressed_linenumber_table()); 709 while (stream.read_pair()) { 710 if (stream.bci() == bci) { 711 // perfect match 712 return stream.line(); 713 } else { 714 // update best_bci/line 715 if (stream.bci() < bci && stream.bci() >= best_bci) { 716 best_bci = stream.bci(); 717 best_line = stream.line(); 718 } 719 } 720 } 721 } 722 return best_line; 723 } 724 725 726 bool Method::is_klass_loaded_by_klass_index(int klass_index) const { 727 if( constants()->tag_at(klass_index).is_unresolved_klass() ) { 728 Thread *thread = Thread::current(); 729 Symbol* klass_name = constants()->klass_name_at(klass_index); 730 Handle loader(thread, method_holder()->class_loader()); 731 Handle prot (thread, method_holder()->protection_domain()); 732 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL; 733 } else { 734 return true; 735 } 736 } 737 738 739 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const { 740 int klass_index = constants()->klass_ref_index_at(refinfo_index); 741 if (must_be_resolved) { 742 // Make sure klass is resolved in constantpool. 743 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false; 744 } 745 return is_klass_loaded_by_klass_index(klass_index); 746 } 747 748 749 void Method::set_native_function(address function, bool post_event_flag) { 750 assert(function != NULL, "use clear_native_function to unregister natives"); 751 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), ""); 752 address* native_function = native_function_addr(); 753 754 // We can see racers trying to place the same native function into place. Once 755 // is plenty. 756 address current = *native_function; 757 if (current == function) return; 758 if (post_event_flag && JvmtiExport::should_post_native_method_bind() && 759 function != NULL) { 760 // native_method_throw_unsatisfied_link_error_entry() should only 761 // be passed when post_event_flag is false. 762 assert(function != 763 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), 764 "post_event_flag mis-match"); 765 766 // post the bind event, and possible change the bind function 767 JvmtiExport::post_native_method_bind(this, &function); 768 } 769 *native_function = function; 770 // This function can be called more than once. We must make sure that we always 771 // use the latest registered method -> check if a stub already has been generated. 772 // If so, we have to make it not_entrant. 773 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates 774 if (nm != NULL) { 775 nm->make_not_entrant(); 776 } 777 } 778 779 780 bool Method::has_native_function() const { 781 if (is_method_handle_intrinsic()) 782 return false; // special-cased in SharedRuntime::generate_native_wrapper 783 address func = native_function(); 784 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry()); 785 } 786 787 788 void Method::clear_native_function() { 789 // Note: is_method_handle_intrinsic() is allowed here. 790 set_native_function( 791 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), 792 !native_bind_event_is_interesting); 793 clear_code(); 794 } 795 796 address Method::critical_native_function() { 797 methodHandle mh(this); 798 return NativeLookup::lookup_critical_entry(mh); 799 } 800 801 802 void Method::set_signature_handler(address handler) { 803 address* signature_handler = signature_handler_addr(); 804 *signature_handler = handler; 805 } 806 807 808 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) { 809 if (PrintCompilation && report) { 810 ttyLocker ttyl; 811 tty->print("made not %scompilable on ", is_osr ? "OSR " : ""); 812 if (comp_level == CompLevel_all) { 813 tty->print("all levels "); 814 } else { 815 tty->print("levels "); 816 for (int i = (int)CompLevel_none; i <= comp_level; i++) { 817 tty->print("%d ", i); 818 } 819 } 820 this->print_short_name(tty); 821 int size = this->code_size(); 822 if (size > 0) { 823 tty->print(" (%d bytes)", size); 824 } 825 if (reason != NULL) { 826 tty->print(" %s", reason); 827 } 828 tty->cr(); 829 } 830 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) { 831 ttyLocker ttyl; 832 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'", 833 os::current_thread_id(), is_osr, comp_level); 834 if (reason != NULL) { 835 xtty->print(" reason=\'%s\'", reason); 836 } 837 xtty->method(this); 838 xtty->stamp(); 839 xtty->end_elem(); 840 } 841 } 842 843 bool Method::is_always_compilable() const { 844 // Generated adapters must be compiled 845 if (is_method_handle_intrinsic() && is_synthetic()) { 846 assert(!is_not_c1_compilable(), "sanity check"); 847 assert(!is_not_c2_compilable(), "sanity check"); 848 return true; 849 } 850 851 return false; 852 } 853 854 bool Method::is_not_compilable(int comp_level) const { 855 if (number_of_breakpoints() > 0) 856 return true; 857 if (is_always_compilable()) 858 return false; 859 if (comp_level == CompLevel_any) 860 return is_not_c1_compilable() || is_not_c2_compilable(); 861 if (is_c1_compile(comp_level)) 862 return is_not_c1_compilable(); 863 if (is_c2_compile(comp_level)) 864 return is_not_c2_compilable(); 865 return false; 866 } 867 868 // call this when compiler finds that this method is not compilable 869 void Method::set_not_compilable(int comp_level, bool report, const char* reason) { 870 if (is_always_compilable()) { 871 // Don't mark a method which should be always compilable 872 return; 873 } 874 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason); 875 if (comp_level == CompLevel_all) { 876 set_not_c1_compilable(); 877 set_not_c2_compilable(); 878 } else { 879 if (is_c1_compile(comp_level)) 880 set_not_c1_compilable(); 881 if (is_c2_compile(comp_level)) 882 set_not_c2_compilable(); 883 } 884 CompilationPolicy::policy()->disable_compilation(this); 885 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check"); 886 } 887 888 bool Method::is_not_osr_compilable(int comp_level) const { 889 if (is_not_compilable(comp_level)) 890 return true; 891 if (comp_level == CompLevel_any) 892 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable(); 893 if (is_c1_compile(comp_level)) 894 return is_not_c1_osr_compilable(); 895 if (is_c2_compile(comp_level)) 896 return is_not_c2_osr_compilable(); 897 return false; 898 } 899 900 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) { 901 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason); 902 if (comp_level == CompLevel_all) { 903 set_not_c1_osr_compilable(); 904 set_not_c2_osr_compilable(); 905 } else { 906 if (is_c1_compile(comp_level)) 907 set_not_c1_osr_compilable(); 908 if (is_c2_compile(comp_level)) 909 set_not_c2_osr_compilable(); 910 } 911 CompilationPolicy::policy()->disable_compilation(this); 912 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check"); 913 } 914 915 // Revert to using the interpreter and clear out the nmethod 916 void Method::clear_code(bool acquire_lock /* = true */) { 917 MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag); 918 // this may be NULL if c2i adapters have not been made yet 919 // Only should happen at allocate time. 920 if (adapter() == NULL) { 921 _from_compiled_entry = NULL; 922 } else { 923 _from_compiled_entry = adapter()->get_c2i_entry(); 924 } 925 OrderAccess::storestore(); 926 _from_interpreted_entry = _i2i_entry; 927 OrderAccess::storestore(); 928 _code = NULL; 929 } 930 931 #if INCLUDE_CDS 932 // Called by class data sharing to remove any entry points (which are not shared) 933 void Method::unlink_method() { 934 _code = NULL; 935 936 assert(DumpSharedSpaces, "dump time only"); 937 // Set the values to what they should be at run time. Note that 938 // this Method can no longer be executed during dump time. 939 _i2i_entry = Interpreter::entry_for_cds_method(this); 940 _from_interpreted_entry = _i2i_entry; 941 942 if (is_native()) { 943 *native_function_addr() = NULL; 944 set_signature_handler(NULL); 945 } 946 NOT_PRODUCT(set_compiled_invocation_count(0);) 947 948 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter(); 949 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline()); 950 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline(); 951 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time"); 952 953 set_method_data(NULL); 954 clear_method_counters(); 955 } 956 #endif 957 958 /**************************************************************************** 959 // The following illustrates how the entries work for CDS shared Methods: 960 // 961 // Our goal is to delay writing into a shared Method until it's compiled. 962 // Hence, we want to determine the initial values for _i2i_entry, 963 // _from_interpreted_entry and _from_compiled_entry during CDS dump time. 964 // 965 // In this example, both Methods A and B have the _i2i_entry of "zero_locals". 966 // They also have similar signatures so that they will share the same 967 // AdapterHandlerEntry. 968 // 969 // _adapter_trampoline points to a fixed location in the RW section of 970 // the CDS archive. This location initially contains a NULL pointer. When the 971 // first of method A or B is linked, an AdapterHandlerEntry is allocated 972 // dynamically, and its c2i/i2c entries are generated. 973 // 974 // _i2i_entry and _from_interpreted_entry initially points to the same 975 // (fixed) location in the CODE section of the CDS archive. This contains 976 // an unconditional branch to the actual entry for "zero_locals", which is 977 // generated at run time and may be on an arbitrary address. Thus, the 978 // unconditional branch is also generated at run time to jump to the correct 979 // address. 980 // 981 // Similarly, _from_compiled_entry points to a fixed address in the CODE 982 // section. This address has enough space for an unconditional branch 983 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is 984 // initialized, and the address for the actual c2i_entry is known, we emit a 985 // branch instruction here to branch to the actual c2i_entry. 986 // 987 // The effect of the extra branch on the i2i and c2i entries is negligible. 988 // 989 // The reason for putting _adapter_trampoline in RO is many shared Methods 990 // share the same AdapterHandlerEntry, so we can save space in the RW section 991 // by having the extra indirection. 992 993 994 [Method A: RW] 995 _constMethod ----> [ConstMethod: RO] 996 _adapter_trampoline -----------+ 997 | 998 _i2i_entry (same value as method B) | 999 _from_interpreted_entry (same value as method B) | 1000 _from_compiled_entry (same value as method B) | 1001 | 1002 | 1003 [Method B: RW] +--------+ 1004 _constMethod ----> [ConstMethod: RO] | 1005 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+ 1006 | 1007 +-------------------------------+ 1008 | 1009 +----> [AdapterHandlerEntry] (allocated at run time) 1010 _fingerprint 1011 _c2i_entry ---------------------------------+->[c2i entry..] 1012 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] | 1013 _from_interpreted_entry | _c2i_unverified_entry | | 1014 | | | | 1015 | | (_cds_entry_table: CODE) | | 1016 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | | 1017 | | (allocated at run time) | | 1018 | | ... [asm code ...] | | 1019 +-[not compiled]-+ [n]: jmp _entry_table[n] | | 1020 | | | 1021 | | | 1022 +-[compiled]-------------------------------------------------------------------+ | 1023 | 1024 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) | 1025 [jmp c2i_entry] ------------------------------------------------------+ 1026 1027 ***/ 1028 1029 // Called when the method_holder is getting linked. Setup entrypoints so the method 1030 // is ready to be called from interpreter, compiler, and vtables. 1031 void Method::link_method(const methodHandle& h_method, TRAPS) { 1032 // If the code cache is full, we may reenter this function for the 1033 // leftover methods that weren't linked. 1034 if (is_shared()) { 1035 address entry = Interpreter::entry_for_cds_method(h_method); 1036 assert(entry != NULL && entry == _i2i_entry, 1037 "should be correctly set during dump time"); 1038 if (adapter() != NULL) { 1039 return; 1040 } 1041 assert(entry == _from_interpreted_entry, 1042 "should be correctly set during dump time"); 1043 } else if (_i2i_entry != NULL) { 1044 return; 1045 } 1046 assert( _code == NULL, "nothing compiled yet" ); 1047 1048 // Setup interpreter entrypoint 1049 assert(this == h_method(), "wrong h_method()" ); 1050 1051 if (!is_shared()) { 1052 assert(adapter() == NULL, "init'd to NULL"); 1053 address entry = Interpreter::entry_for_method(h_method); 1054 assert(entry != NULL, "interpreter entry must be non-null"); 1055 // Sets both _i2i_entry and _from_interpreted_entry 1056 set_interpreter_entry(entry); 1057 } 1058 1059 // Don't overwrite already registered native entries. 1060 if (is_native() && !has_native_function()) { 1061 set_native_function( 1062 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), 1063 !native_bind_event_is_interesting); 1064 } 1065 1066 // Setup compiler entrypoint. This is made eagerly, so we do not need 1067 // special handling of vtables. An alternative is to make adapters more 1068 // lazily by calling make_adapter() from from_compiled_entry() for the 1069 // normal calls. For vtable calls life gets more complicated. When a 1070 // call-site goes mega-morphic we need adapters in all methods which can be 1071 // called from the vtable. We need adapters on such methods that get loaded 1072 // later. Ditto for mega-morphic itable calls. If this proves to be a 1073 // problem we'll make these lazily later. 1074 (void) make_adapters(h_method, CHECK); 1075 1076 // ONLY USE the h_method now as make_adapter may have blocked 1077 1078 } 1079 1080 address Method::make_adapters(const methodHandle& mh, TRAPS) { 1081 // Adapters for compiled code are made eagerly here. They are fairly 1082 // small (generally < 100 bytes) and quick to make (and cached and shared) 1083 // so making them eagerly shouldn't be too expensive. 1084 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh); 1085 if (adapter == NULL ) { 1086 if (!is_init_completed()) { 1087 // Don't throw exceptions during VM initialization because java.lang.* classes 1088 // might not have been initialized, causing problems when constructing the 1089 // Java exception object. 1090 vm_exit_during_initialization("Out of space in CodeCache for adapters"); 1091 } else { 1092 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters"); 1093 } 1094 } 1095 1096 if (mh->is_shared()) { 1097 assert(mh->adapter() == adapter, "must be"); 1098 assert(mh->_from_compiled_entry != NULL, "must be"); 1099 } else { 1100 mh->set_adapter_entry(adapter); 1101 mh->_from_compiled_entry = adapter->get_c2i_entry(); 1102 } 1103 return adapter->get_c2i_entry(); 1104 } 1105 1106 void Method::restore_unshareable_info(TRAPS) { 1107 assert(is_method() && is_valid_method(), "ensure C++ vtable is restored"); 1108 1109 // Since restore_unshareable_info can be called more than once for a method, don't 1110 // redo any work. 1111 if (adapter() == NULL) { 1112 methodHandle mh(THREAD, this); 1113 link_method(mh, CHECK); 1114 } 1115 } 1116 1117 address Method::from_compiled_entry_no_trampoline() const { 1118 CompiledMethod *code = OrderAccess::load_acquire(&_code); 1119 if (code) { 1120 return code->verified_entry_point(); 1121 } else { 1122 return adapter()->get_c2i_entry(); 1123 } 1124 } 1125 1126 // The verified_code_entry() must be called when a invoke is resolved 1127 // on this method. 1128 1129 // It returns the compiled code entry point, after asserting not null. 1130 // This function is called after potential safepoints so that nmethod 1131 // or adapter that it points to is still live and valid. 1132 // This function must not hit a safepoint! 1133 address Method::verified_code_entry() { 1134 debug_only(NoSafepointVerifier nsv;) 1135 assert(_from_compiled_entry != NULL, "must be set"); 1136 return _from_compiled_entry; 1137 } 1138 1139 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all 1140 // (could be racing a deopt). 1141 // Not inline to avoid circular ref. 1142 bool Method::check_code() const { 1143 // cached in a register or local. There's a race on the value of the field. 1144 CompiledMethod *code = OrderAccess::load_acquire(&_code); 1145 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method()); 1146 } 1147 1148 // Install compiled code. Instantly it can execute. 1149 void Method::set_code(const methodHandle& mh, CompiledMethod *code) { 1150 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag); 1151 assert( code, "use clear_code to remove code" ); 1152 assert( mh->check_code(), "" ); 1153 1154 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!"); 1155 1156 // These writes must happen in this order, because the interpreter will 1157 // directly jump to from_interpreted_entry which jumps to an i2c adapter 1158 // which jumps to _from_compiled_entry. 1159 mh->_code = code; // Assign before allowing compiled code to exec 1160 1161 int comp_level = code->comp_level(); 1162 // In theory there could be a race here. In practice it is unlikely 1163 // and not worth worrying about. 1164 if (comp_level > mh->highest_comp_level()) { 1165 mh->set_highest_comp_level(comp_level); 1166 } 1167 1168 OrderAccess::storestore(); 1169 mh->_from_compiled_entry = code->verified_entry_point(); 1170 OrderAccess::storestore(); 1171 // Instantly compiled code can execute. 1172 if (!mh->is_method_handle_intrinsic()) 1173 mh->_from_interpreted_entry = mh->get_i2c_entry(); 1174 } 1175 1176 1177 bool Method::is_overridden_in(Klass* k) const { 1178 InstanceKlass* ik = InstanceKlass::cast(k); 1179 1180 if (ik->is_interface()) return false; 1181 1182 // If method is an interface, we skip it - except if it 1183 // is a miranda method 1184 if (method_holder()->is_interface()) { 1185 // Check that method is not a miranda method 1186 if (ik->lookup_method(name(), signature()) == NULL) { 1187 // No implementation exist - so miranda method 1188 return false; 1189 } 1190 return true; 1191 } 1192 1193 assert(ik->is_subclass_of(method_holder()), "should be subklass"); 1194 if (!has_vtable_index()) { 1195 return false; 1196 } else { 1197 Method* vt_m = ik->method_at_vtable(vtable_index()); 1198 return vt_m != this; 1199 } 1200 } 1201 1202 1203 // give advice about whether this Method* should be cached or not 1204 bool Method::should_not_be_cached() const { 1205 if (is_old()) { 1206 // This method has been redefined. It is either EMCP or obsolete 1207 // and we don't want to cache it because that would pin the method 1208 // down and prevent it from being collectible if and when it 1209 // finishes executing. 1210 return true; 1211 } 1212 1213 // caching this method should be just fine 1214 return false; 1215 } 1216 1217 1218 /** 1219 * Returns true if this is one of the specially treated methods for 1220 * security related stack walks (like Reflection.getCallerClass). 1221 */ 1222 bool Method::is_ignored_by_security_stack_walk() const { 1223 if (intrinsic_id() == vmIntrinsics::_invoke) { 1224 // This is Method.invoke() -- ignore it 1225 return true; 1226 } 1227 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) { 1228 // This is an auxilary frame -- ignore it 1229 return true; 1230 } 1231 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) { 1232 // This is an internal adapter frame for method handles -- ignore it 1233 return true; 1234 } 1235 return false; 1236 } 1237 1238 1239 // Constant pool structure for invoke methods: 1240 enum { 1241 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc. 1242 _imcp_invoke_signature, // utf8: (variable Symbol*) 1243 _imcp_limit 1244 }; 1245 1246 // Test if this method is an MH adapter frame generated by Java code. 1247 // Cf. java/lang/invoke/InvokerBytecodeGenerator 1248 bool Method::is_compiled_lambda_form() const { 1249 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm; 1250 } 1251 1252 // Test if this method is an internal MH primitive method. 1253 bool Method::is_method_handle_intrinsic() const { 1254 vmIntrinsics::ID iid = intrinsic_id(); 1255 return (MethodHandles::is_signature_polymorphic(iid) && 1256 MethodHandles::is_signature_polymorphic_intrinsic(iid)); 1257 } 1258 1259 bool Method::has_member_arg() const { 1260 vmIntrinsics::ID iid = intrinsic_id(); 1261 return (MethodHandles::is_signature_polymorphic(iid) && 1262 MethodHandles::has_member_arg(iid)); 1263 } 1264 1265 // Make an instance of a signature-polymorphic internal MH primitive. 1266 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid, 1267 Symbol* signature, 1268 TRAPS) { 1269 ResourceMark rm; 1270 methodHandle empty; 1271 1272 InstanceKlass* holder = SystemDictionary::MethodHandle_klass(); 1273 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid); 1274 assert(iid == MethodHandles::signature_polymorphic_name_id(name), ""); 1275 if (TraceMethodHandles) { 1276 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string()); 1277 } 1278 1279 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup) 1280 name->increment_refcount(); 1281 signature->increment_refcount(); 1282 1283 int cp_length = _imcp_limit; 1284 ClassLoaderData* loader_data = holder->class_loader_data(); 1285 constantPoolHandle cp; 1286 { 1287 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty)); 1288 cp = constantPoolHandle(THREAD, cp_oop); 1289 } 1290 cp->set_pool_holder(holder); 1291 cp->symbol_at_put(_imcp_invoke_name, name); 1292 cp->symbol_at_put(_imcp_invoke_signature, signature); 1293 cp->set_has_preresolution(); 1294 1295 // decide on access bits: public or not? 1296 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL); 1297 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid); 1298 if (must_be_static) flags_bits |= JVM_ACC_STATIC; 1299 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods"); 1300 1301 methodHandle m; 1302 { 1303 InlineTableSizes sizes; 1304 Method* m_oop = Method::allocate(loader_data, 0, 1305 accessFlags_from(flags_bits), &sizes, 1306 ConstMethod::NORMAL, CHECK_(empty)); 1307 m = methodHandle(THREAD, m_oop); 1308 } 1309 m->set_constants(cp()); 1310 m->set_name_index(_imcp_invoke_name); 1311 m->set_signature_index(_imcp_invoke_signature); 1312 assert(MethodHandles::is_signature_polymorphic_name(m->name()), ""); 1313 assert(m->signature() == signature, ""); 1314 ResultTypeFinder rtf(signature); 1315 m->constMethod()->set_result_type(rtf.type()); 1316 m->compute_size_of_parameters(THREAD); 1317 m->init_intrinsic_id(); 1318 assert(m->is_method_handle_intrinsic(), ""); 1319 #ifdef ASSERT 1320 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print(); 1321 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker"); 1322 assert(m->intrinsic_id() == iid, "correctly predicted iid"); 1323 #endif //ASSERT 1324 1325 // Finally, set up its entry points. 1326 assert(m->can_be_statically_bound(), ""); 1327 m->set_vtable_index(Method::nonvirtual_vtable_index); 1328 m->link_method(m, CHECK_(empty)); 1329 1330 if (TraceMethodHandles && (Verbose || WizardMode)) { 1331 ttyLocker ttyl; 1332 m->print_on(tty); 1333 } 1334 1335 return m; 1336 } 1337 1338 Klass* Method::check_non_bcp_klass(Klass* klass) { 1339 if (klass != NULL && klass->class_loader() != NULL) { 1340 if (klass->is_objArray_klass()) 1341 klass = ObjArrayKlass::cast(klass)->bottom_klass(); 1342 return klass; 1343 } 1344 return NULL; 1345 } 1346 1347 1348 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length, 1349 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) { 1350 // Code below does not work for native methods - they should never get rewritten anyway 1351 assert(!m->is_native(), "cannot rewrite native methods"); 1352 // Allocate new Method* 1353 AccessFlags flags = m->access_flags(); 1354 1355 ConstMethod* cm = m->constMethod(); 1356 int checked_exceptions_len = cm->checked_exceptions_length(); 1357 int localvariable_len = cm->localvariable_table_length(); 1358 int exception_table_len = cm->exception_table_length(); 1359 int method_parameters_len = cm->method_parameters_length(); 1360 int method_annotations_len = cm->method_annotations_length(); 1361 int parameter_annotations_len = cm->parameter_annotations_length(); 1362 int type_annotations_len = cm->type_annotations_length(); 1363 int default_annotations_len = cm->default_annotations_length(); 1364 1365 InlineTableSizes sizes( 1366 localvariable_len, 1367 new_compressed_linenumber_size, 1368 exception_table_len, 1369 checked_exceptions_len, 1370 method_parameters_len, 1371 cm->generic_signature_index(), 1372 method_annotations_len, 1373 parameter_annotations_len, 1374 type_annotations_len, 1375 default_annotations_len, 1376 0); 1377 1378 ClassLoaderData* loader_data = m->method_holder()->class_loader_data(); 1379 Method* newm_oop = Method::allocate(loader_data, 1380 new_code_length, 1381 flags, 1382 &sizes, 1383 m->method_type(), 1384 CHECK_(methodHandle())); 1385 methodHandle newm (THREAD, newm_oop); 1386 1387 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod* 1388 ConstMethod* newcm = newm->constMethod(); 1389 int new_const_method_size = newm->constMethod()->size(); 1390 1391 // This works because the source and target are both Methods. Some compilers 1392 // (e.g., clang) complain that the target vtable pointer will be stomped, 1393 // so cast away newm()'s and m()'s Methodness. 1394 memcpy((void*)newm(), (void*)m(), sizeof(Method)); 1395 1396 // Create shallow copy of ConstMethod. 1397 memcpy(newcm, m->constMethod(), sizeof(ConstMethod)); 1398 1399 // Reset correct method/const method, method size, and parameter info 1400 newm->set_constMethod(newcm); 1401 newm->constMethod()->set_code_size(new_code_length); 1402 newm->constMethod()->set_constMethod_size(new_const_method_size); 1403 assert(newm->code_size() == new_code_length, "check"); 1404 assert(newm->method_parameters_length() == method_parameters_len, "check"); 1405 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check"); 1406 assert(newm->exception_table_length() == exception_table_len, "check"); 1407 assert(newm->localvariable_table_length() == localvariable_len, "check"); 1408 // Copy new byte codes 1409 memcpy(newm->code_base(), new_code, new_code_length); 1410 // Copy line number table 1411 if (new_compressed_linenumber_size > 0) { 1412 memcpy(newm->compressed_linenumber_table(), 1413 new_compressed_linenumber_table, 1414 new_compressed_linenumber_size); 1415 } 1416 // Copy method_parameters 1417 if (method_parameters_len > 0) { 1418 memcpy(newm->method_parameters_start(), 1419 m->method_parameters_start(), 1420 method_parameters_len * sizeof(MethodParametersElement)); 1421 } 1422 // Copy checked_exceptions 1423 if (checked_exceptions_len > 0) { 1424 memcpy(newm->checked_exceptions_start(), 1425 m->checked_exceptions_start(), 1426 checked_exceptions_len * sizeof(CheckedExceptionElement)); 1427 } 1428 // Copy exception table 1429 if (exception_table_len > 0) { 1430 memcpy(newm->exception_table_start(), 1431 m->exception_table_start(), 1432 exception_table_len * sizeof(ExceptionTableElement)); 1433 } 1434 // Copy local variable number table 1435 if (localvariable_len > 0) { 1436 memcpy(newm->localvariable_table_start(), 1437 m->localvariable_table_start(), 1438 localvariable_len * sizeof(LocalVariableTableElement)); 1439 } 1440 // Copy stackmap table 1441 if (m->has_stackmap_table()) { 1442 int code_attribute_length = m->stackmap_data()->length(); 1443 Array<u1>* stackmap_data = 1444 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL); 1445 memcpy((void*)stackmap_data->adr_at(0), 1446 (void*)m->stackmap_data()->adr_at(0), code_attribute_length); 1447 newm->set_stackmap_data(stackmap_data); 1448 } 1449 1450 // copy annotations over to new method 1451 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL); 1452 return newm; 1453 } 1454 1455 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) { 1456 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics 1457 // because we are not loading from core libraries 1458 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar 1459 // which does not use the class default class loader so we check for its loader here 1460 const InstanceKlass* ik = InstanceKlass::cast(holder); 1461 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) { 1462 return vmSymbols::NO_SID; // regardless of name, no intrinsics here 1463 } 1464 1465 // see if the klass name is well-known: 1466 Symbol* klass_name = ik->name(); 1467 return vmSymbols::find_sid(klass_name); 1468 } 1469 1470 void Method::init_intrinsic_id() { 1471 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once"); 1472 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte)); 1473 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size"); 1474 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), ""); 1475 1476 // the klass name is well-known: 1477 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder()); 1478 assert(klass_id != vmSymbols::NO_SID, "caller responsibility"); 1479 1480 // ditto for method and signature: 1481 vmSymbols::SID name_id = vmSymbols::find_sid(name()); 1482 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle) 1483 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle) 1484 && name_id == vmSymbols::NO_SID) { 1485 return; 1486 } 1487 vmSymbols::SID sig_id = vmSymbols::find_sid(signature()); 1488 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle) 1489 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle) 1490 && sig_id == vmSymbols::NO_SID) { 1491 return; 1492 } 1493 jshort flags = access_flags().as_short(); 1494 1495 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags); 1496 if (id != vmIntrinsics::_none) { 1497 set_intrinsic_id(id); 1498 if (id == vmIntrinsics::_Class_cast) { 1499 // Even if the intrinsic is rejected, we want to inline this simple method. 1500 set_force_inline(true); 1501 } 1502 return; 1503 } 1504 1505 // A few slightly irregular cases: 1506 switch (klass_id) { 1507 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath): 1508 // Second chance: check in regular Math. 1509 switch (name_id) { 1510 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name): 1511 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name): 1512 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name): 1513 // pretend it is the corresponding method in the non-strict class: 1514 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math); 1515 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags); 1516 break; 1517 default: 1518 break; 1519 } 1520 break; 1521 1522 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle 1523 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle): 1524 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle): 1525 if (!is_native()) break; 1526 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name()); 1527 if (is_static() != MethodHandles::is_signature_polymorphic_static(id)) 1528 id = vmIntrinsics::_none; 1529 break; 1530 1531 default: 1532 break; 1533 } 1534 1535 if (id != vmIntrinsics::_none) { 1536 // Set up its iid. It is an alias method. 1537 set_intrinsic_id(id); 1538 return; 1539 } 1540 } 1541 1542 // These two methods are static since a GC may move the Method 1543 bool Method::load_signature_classes(const methodHandle& m, TRAPS) { 1544 if (!THREAD->can_call_java()) { 1545 // There is nothing useful this routine can do from within the Compile thread. 1546 // Hopefully, the signature contains only well-known classes. 1547 // We could scan for this and return true/false, but the caller won't care. 1548 return false; 1549 } 1550 bool sig_is_loaded = true; 1551 Handle class_loader(THREAD, m->method_holder()->class_loader()); 1552 Handle protection_domain(THREAD, m->method_holder()->protection_domain()); 1553 ResourceMark rm(THREAD); 1554 Symbol* signature = m->signature(); 1555 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) { 1556 if (ss.is_object()) { 1557 Symbol* sym = ss.as_symbol(CHECK_(false)); 1558 Symbol* name = sym; 1559 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader, 1560 protection_domain, THREAD); 1561 // We are loading classes eagerly. If a ClassNotFoundException or 1562 // a LinkageError was generated, be sure to ignore it. 1563 if (HAS_PENDING_EXCEPTION) { 1564 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) || 1565 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) { 1566 CLEAR_PENDING_EXCEPTION; 1567 } else { 1568 return false; 1569 } 1570 } 1571 if( klass == NULL) { sig_is_loaded = false; } 1572 } 1573 } 1574 return sig_is_loaded; 1575 } 1576 1577 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) { 1578 Handle class_loader(THREAD, m->method_holder()->class_loader()); 1579 Handle protection_domain(THREAD, m->method_holder()->protection_domain()); 1580 ResourceMark rm(THREAD); 1581 Symbol* signature = m->signature(); 1582 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) { 1583 if (ss.type() == T_OBJECT) { 1584 Symbol* name = ss.as_symbol_or_null(); 1585 if (name == NULL) return true; 1586 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD); 1587 if (klass == NULL) return true; 1588 } 1589 } 1590 return false; 1591 } 1592 1593 // Exposed so field engineers can debug VM 1594 void Method::print_short_name(outputStream* st) { 1595 ResourceMark rm; 1596 #ifdef PRODUCT 1597 st->print(" %s::", method_holder()->external_name()); 1598 #else 1599 st->print(" %s::", method_holder()->internal_name()); 1600 #endif 1601 name()->print_symbol_on(st); 1602 if (WizardMode) signature()->print_symbol_on(st); 1603 else if (MethodHandles::is_signature_polymorphic(intrinsic_id())) 1604 MethodHandles::print_as_basic_type_signature_on(st, signature(), true); 1605 } 1606 1607 // Comparer for sorting an object array containing 1608 // Method*s. 1609 static int method_comparator(Method* a, Method* b) { 1610 return a->name()->fast_compare(b->name()); 1611 } 1612 1613 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array 1614 // default_methods also uses this without the ordering for fast find_method 1615 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) { 1616 int length = methods->length(); 1617 if (length > 1) { 1618 { 1619 NoSafepointVerifier nsv; 1620 QuickSort::sort(methods->data(), length, method_comparator, idempotent); 1621 } 1622 // Reset method ordering 1623 if (set_idnums) { 1624 for (int i = 0; i < length; i++) { 1625 Method* m = methods->at(i); 1626 m->set_method_idnum(i); 1627 m->set_orig_method_idnum(i); 1628 } 1629 } 1630 } 1631 } 1632 1633 //----------------------------------------------------------------------------------- 1634 // Non-product code unless JVM/TI needs it 1635 1636 #if !defined(PRODUCT) || INCLUDE_JVMTI 1637 class SignatureTypePrinter : public SignatureTypeNames { 1638 private: 1639 outputStream* _st; 1640 bool _use_separator; 1641 1642 void type_name(const char* name) { 1643 if (_use_separator) _st->print(", "); 1644 _st->print("%s", name); 1645 _use_separator = true; 1646 } 1647 1648 public: 1649 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) { 1650 _st = st; 1651 _use_separator = false; 1652 } 1653 1654 void print_parameters() { _use_separator = false; iterate_parameters(); } 1655 void print_returntype() { _use_separator = false; iterate_returntype(); } 1656 }; 1657 1658 1659 void Method::print_name(outputStream* st) { 1660 Thread *thread = Thread::current(); 1661 ResourceMark rm(thread); 1662 st->print("%s ", is_static() ? "static" : "virtual"); 1663 if (WizardMode) { 1664 st->print("%s.", method_holder()->internal_name()); 1665 name()->print_symbol_on(st); 1666 signature()->print_symbol_on(st); 1667 } else { 1668 SignatureTypePrinter sig(signature(), st); 1669 sig.print_returntype(); 1670 st->print(" %s.", method_holder()->internal_name()); 1671 name()->print_symbol_on(st); 1672 st->print("("); 1673 sig.print_parameters(); 1674 st->print(")"); 1675 } 1676 } 1677 #endif // !PRODUCT || INCLUDE_JVMTI 1678 1679 1680 void Method::print_codes_on(outputStream* st) const { 1681 print_codes_on(0, code_size(), st); 1682 } 1683 1684 void Method::print_codes_on(int from, int to, outputStream* st) const { 1685 Thread *thread = Thread::current(); 1686 ResourceMark rm(thread); 1687 methodHandle mh (thread, (Method*)this); 1688 BytecodeStream s(mh); 1689 s.set_interval(from, to); 1690 BytecodeTracer::set_closure(BytecodeTracer::std_closure()); 1691 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st); 1692 } 1693 1694 1695 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas 1696 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned) 1697 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used 1698 // as end-of-stream terminator. 1699 1700 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) { 1701 // bci and line number does not compress into single byte. 1702 // Write out escape character and use regular compression for bci and line number. 1703 write_byte((jubyte)0xFF); 1704 write_signed_int(bci_delta); 1705 write_signed_int(line_delta); 1706 } 1707 1708 // See comment in method.hpp which explains why this exists. 1709 #if defined(_M_AMD64) && _MSC_VER >= 1400 1710 #pragma optimize("", off) 1711 void CompressedLineNumberWriteStream::write_pair(int bci, int line) { 1712 write_pair_inline(bci, line); 1713 } 1714 #pragma optimize("", on) 1715 #endif 1716 1717 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) { 1718 _bci = 0; 1719 _line = 0; 1720 }; 1721 1722 1723 bool CompressedLineNumberReadStream::read_pair() { 1724 jubyte next = read_byte(); 1725 // Check for terminator 1726 if (next == 0) return false; 1727 if (next == 0xFF) { 1728 // Escape character, regular compression used 1729 _bci += read_signed_int(); 1730 _line += read_signed_int(); 1731 } else { 1732 // Single byte compression used 1733 _bci += next >> 3; 1734 _line += next & 0x7; 1735 } 1736 return true; 1737 } 1738 1739 #if INCLUDE_JVMTI 1740 1741 Bytecodes::Code Method::orig_bytecode_at(int bci) const { 1742 BreakpointInfo* bp = method_holder()->breakpoints(); 1743 for (; bp != NULL; bp = bp->next()) { 1744 if (bp->match(this, bci)) { 1745 return bp->orig_bytecode(); 1746 } 1747 } 1748 { 1749 ResourceMark rm; 1750 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci); 1751 } 1752 return Bytecodes::_shouldnotreachhere; 1753 } 1754 1755 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) { 1756 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way"); 1757 BreakpointInfo* bp = method_holder()->breakpoints(); 1758 for (; bp != NULL; bp = bp->next()) { 1759 if (bp->match(this, bci)) { 1760 bp->set_orig_bytecode(code); 1761 // and continue, in case there is more than one 1762 } 1763 } 1764 } 1765 1766 void Method::set_breakpoint(int bci) { 1767 InstanceKlass* ik = method_holder(); 1768 BreakpointInfo *bp = new BreakpointInfo(this, bci); 1769 bp->set_next(ik->breakpoints()); 1770 ik->set_breakpoints(bp); 1771 // do this last: 1772 bp->set(this); 1773 } 1774 1775 static void clear_matches(Method* m, int bci) { 1776 InstanceKlass* ik = m->method_holder(); 1777 BreakpointInfo* prev_bp = NULL; 1778 BreakpointInfo* next_bp; 1779 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) { 1780 next_bp = bp->next(); 1781 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint). 1782 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) { 1783 // do this first: 1784 bp->clear(m); 1785 // unhook it 1786 if (prev_bp != NULL) 1787 prev_bp->set_next(next_bp); 1788 else 1789 ik->set_breakpoints(next_bp); 1790 delete bp; 1791 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods 1792 // at same location. So we have multiple matching (method_index and bci) 1793 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one 1794 // breakpoint for clear_breakpoint request and keep all other method versions 1795 // BreakpointInfo for future clear_breakpoint request. 1796 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints) 1797 // which is being called when class is unloaded. We delete all the Breakpoint 1798 // information for all versions of method. We may not correctly restore the original 1799 // bytecode in all method versions, but that is ok. Because the class is being unloaded 1800 // so these methods won't be used anymore. 1801 if (bci >= 0) { 1802 break; 1803 } 1804 } else { 1805 // This one is a keeper. 1806 prev_bp = bp; 1807 } 1808 } 1809 } 1810 1811 void Method::clear_breakpoint(int bci) { 1812 assert(bci >= 0, ""); 1813 clear_matches(this, bci); 1814 } 1815 1816 void Method::clear_all_breakpoints() { 1817 clear_matches(this, -1); 1818 } 1819 1820 #endif // INCLUDE_JVMTI 1821 1822 int Method::invocation_count() { 1823 MethodCounters *mcs = method_counters(); 1824 if (TieredCompilation) { 1825 MethodData* const mdo = method_data(); 1826 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) || 1827 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) { 1828 return InvocationCounter::count_limit; 1829 } else { 1830 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) + 1831 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0); 1832 } 1833 } else { 1834 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count(); 1835 } 1836 } 1837 1838 int Method::backedge_count() { 1839 MethodCounters *mcs = method_counters(); 1840 if (TieredCompilation) { 1841 MethodData* const mdo = method_data(); 1842 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) || 1843 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) { 1844 return InvocationCounter::count_limit; 1845 } else { 1846 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) + 1847 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0); 1848 } 1849 } else { 1850 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count(); 1851 } 1852 } 1853 1854 int Method::highest_comp_level() const { 1855 const MethodCounters* mcs = method_counters(); 1856 if (mcs != NULL) { 1857 return mcs->highest_comp_level(); 1858 } else { 1859 return CompLevel_none; 1860 } 1861 } 1862 1863 int Method::highest_osr_comp_level() const { 1864 const MethodCounters* mcs = method_counters(); 1865 if (mcs != NULL) { 1866 return mcs->highest_osr_comp_level(); 1867 } else { 1868 return CompLevel_none; 1869 } 1870 } 1871 1872 void Method::set_highest_comp_level(int level) { 1873 MethodCounters* mcs = method_counters(); 1874 if (mcs != NULL) { 1875 mcs->set_highest_comp_level(level); 1876 } 1877 } 1878 1879 void Method::set_highest_osr_comp_level(int level) { 1880 MethodCounters* mcs = method_counters(); 1881 if (mcs != NULL) { 1882 mcs->set_highest_osr_comp_level(level); 1883 } 1884 } 1885 1886 #if INCLUDE_JVMTI 1887 1888 BreakpointInfo::BreakpointInfo(Method* m, int bci) { 1889 _bci = bci; 1890 _name_index = m->name_index(); 1891 _signature_index = m->signature_index(); 1892 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci); 1893 if (_orig_bytecode == Bytecodes::_breakpoint) 1894 _orig_bytecode = m->orig_bytecode_at(_bci); 1895 _next = NULL; 1896 } 1897 1898 void BreakpointInfo::set(Method* method) { 1899 #ifdef ASSERT 1900 { 1901 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci); 1902 if (code == Bytecodes::_breakpoint) 1903 code = method->orig_bytecode_at(_bci); 1904 assert(orig_bytecode() == code, "original bytecode must be the same"); 1905 } 1906 #endif 1907 Thread *thread = Thread::current(); 1908 *method->bcp_from(_bci) = Bytecodes::_breakpoint; 1909 method->incr_number_of_breakpoints(thread); 1910 SystemDictionary::notice_modification(); 1911 { 1912 // Deoptimize all dependents on this method 1913 HandleMark hm(thread); 1914 methodHandle mh(thread, method); 1915 CodeCache::flush_dependents_on_method(mh); 1916 } 1917 } 1918 1919 void BreakpointInfo::clear(Method* method) { 1920 *method->bcp_from(_bci) = orig_bytecode(); 1921 assert(method->number_of_breakpoints() > 0, "must not go negative"); 1922 method->decr_number_of_breakpoints(Thread::current()); 1923 } 1924 1925 #endif // INCLUDE_JVMTI 1926 1927 // jmethodID handling 1928 1929 // This is a block allocating object, sort of like JNIHandleBlock, only a 1930 // lot simpler. 1931 // It's allocated on the CHeap because once we allocate a jmethodID, we can 1932 // never get rid of it. 1933 1934 static const int min_block_size = 8; 1935 1936 class JNIMethodBlockNode : public CHeapObj<mtClass> { 1937 friend class JNIMethodBlock; 1938 Method** _methods; 1939 int _number_of_methods; 1940 int _top; 1941 JNIMethodBlockNode* _next; 1942 1943 public: 1944 1945 JNIMethodBlockNode(int num_methods = min_block_size); 1946 1947 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); } 1948 1949 void ensure_methods(int num_addl_methods) { 1950 if (_top < _number_of_methods) { 1951 num_addl_methods -= _number_of_methods - _top; 1952 if (num_addl_methods <= 0) { 1953 return; 1954 } 1955 } 1956 if (_next == NULL) { 1957 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size)); 1958 } else { 1959 _next->ensure_methods(num_addl_methods); 1960 } 1961 } 1962 }; 1963 1964 class JNIMethodBlock : public CHeapObj<mtClass> { 1965 JNIMethodBlockNode _head; 1966 JNIMethodBlockNode *_last_free; 1967 public: 1968 static Method* const _free_method; 1969 1970 JNIMethodBlock(int initial_capacity = min_block_size) 1971 : _head(initial_capacity), _last_free(&_head) {} 1972 1973 void ensure_methods(int num_addl_methods) { 1974 _last_free->ensure_methods(num_addl_methods); 1975 } 1976 1977 Method** add_method(Method* m) { 1978 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) { 1979 if (b->_top < b->_number_of_methods) { 1980 // top points to the next free entry. 1981 int i = b->_top; 1982 b->_methods[i] = m; 1983 b->_top++; 1984 _last_free = b; 1985 return &(b->_methods[i]); 1986 } else if (b->_top == b->_number_of_methods) { 1987 // if the next free entry ran off the block see if there's a free entry 1988 for (int i = 0; i < b->_number_of_methods; i++) { 1989 if (b->_methods[i] == _free_method) { 1990 b->_methods[i] = m; 1991 _last_free = b; 1992 return &(b->_methods[i]); 1993 } 1994 } 1995 // Only check each block once for frees. They're very unlikely. 1996 // Increment top past the end of the block. 1997 b->_top++; 1998 } 1999 // need to allocate a next block. 2000 if (b->_next == NULL) { 2001 b->_next = _last_free = new JNIMethodBlockNode(); 2002 } 2003 } 2004 guarantee(false, "Should always allocate a free block"); 2005 return NULL; 2006 } 2007 2008 bool contains(Method** m) { 2009 if (m == NULL) return false; 2010 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) { 2011 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) { 2012 // This is a bit of extra checking, for two reasons. One is 2013 // that contains() deals with pointers that are passed in by 2014 // JNI code, so making sure that the pointer is aligned 2015 // correctly is valuable. The other is that <= and > are 2016 // technically not defined on pointers, so the if guard can 2017 // pass spuriously; no modern compiler is likely to make that 2018 // a problem, though (and if one did, the guard could also 2019 // fail spuriously, which would be bad). 2020 ptrdiff_t idx = m - b->_methods; 2021 if (b->_methods + idx == m) { 2022 return true; 2023 } 2024 } 2025 } 2026 return false; // not found 2027 } 2028 2029 // Doesn't really destroy it, just marks it as free so it can be reused. 2030 void destroy_method(Method** m) { 2031 #ifdef ASSERT 2032 assert(contains(m), "should be a methodID"); 2033 #endif // ASSERT 2034 *m = _free_method; 2035 } 2036 2037 // During class unloading the methods are cleared, which is different 2038 // than freed. 2039 void clear_all_methods() { 2040 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) { 2041 for (int i = 0; i< b->_number_of_methods; i++) { 2042 b->_methods[i] = NULL; 2043 } 2044 } 2045 } 2046 #ifndef PRODUCT 2047 int count_methods() { 2048 // count all allocated methods 2049 int count = 0; 2050 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) { 2051 for (int i = 0; i< b->_number_of_methods; i++) { 2052 if (b->_methods[i] != _free_method) count++; 2053 } 2054 } 2055 return count; 2056 } 2057 #endif // PRODUCT 2058 }; 2059 2060 // Something that can't be mistaken for an address or a markOop 2061 Method* const JNIMethodBlock::_free_method = (Method*)55; 2062 2063 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) { 2064 _number_of_methods = MAX2(num_methods, min_block_size); 2065 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal); 2066 for (int i = 0; i < _number_of_methods; i++) { 2067 _methods[i] = JNIMethodBlock::_free_method; 2068 } 2069 } 2070 2071 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) { 2072 ClassLoaderData* cld = loader_data; 2073 if (!SafepointSynchronize::is_at_safepoint()) { 2074 // Have to add jmethod_ids() to class loader data thread-safely. 2075 // Also have to add the method to the list safely, which the cld lock 2076 // protects as well. 2077 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag); 2078 if (cld->jmethod_ids() == NULL) { 2079 cld->set_jmethod_ids(new JNIMethodBlock(capacity)); 2080 } else { 2081 cld->jmethod_ids()->ensure_methods(capacity); 2082 } 2083 } else { 2084 // At safepoint, we are single threaded and can set this. 2085 if (cld->jmethod_ids() == NULL) { 2086 cld->set_jmethod_ids(new JNIMethodBlock(capacity)); 2087 } else { 2088 cld->jmethod_ids()->ensure_methods(capacity); 2089 } 2090 } 2091 } 2092 2093 // Add a method id to the jmethod_ids 2094 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) { 2095 ClassLoaderData* cld = loader_data; 2096 2097 if (!SafepointSynchronize::is_at_safepoint()) { 2098 // Have to add jmethod_ids() to class loader data thread-safely. 2099 // Also have to add the method to the list safely, which the cld lock 2100 // protects as well. 2101 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag); 2102 if (cld->jmethod_ids() == NULL) { 2103 cld->set_jmethod_ids(new JNIMethodBlock()); 2104 } 2105 // jmethodID is a pointer to Method* 2106 return (jmethodID)cld->jmethod_ids()->add_method(m); 2107 } else { 2108 // At safepoint, we are single threaded and can set this. 2109 if (cld->jmethod_ids() == NULL) { 2110 cld->set_jmethod_ids(new JNIMethodBlock()); 2111 } 2112 // jmethodID is a pointer to Method* 2113 return (jmethodID)cld->jmethod_ids()->add_method(m); 2114 } 2115 } 2116 2117 // Mark a jmethodID as free. This is called when there is a data race in 2118 // InstanceKlass while creating the jmethodID cache. 2119 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) { 2120 ClassLoaderData* cld = loader_data; 2121 Method** ptr = (Method**)m; 2122 assert(cld->jmethod_ids() != NULL, "should have method handles"); 2123 cld->jmethod_ids()->destroy_method(ptr); 2124 } 2125 2126 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) { 2127 // Can't assert the method_holder is the same because the new method has the 2128 // scratch method holder. 2129 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader() 2130 == new_method->method_holder()->class_loader(), 2131 "changing to a different class loader"); 2132 // Just change the method in place, jmethodID pointer doesn't change. 2133 *((Method**)jmid) = new_method; 2134 } 2135 2136 bool Method::is_method_id(jmethodID mid) { 2137 Method* m = resolve_jmethod_id(mid); 2138 assert(m != NULL, "should be called with non-null method"); 2139 InstanceKlass* ik = m->method_holder(); 2140 ClassLoaderData* cld = ik->class_loader_data(); 2141 if (cld->jmethod_ids() == NULL) return false; 2142 return (cld->jmethod_ids()->contains((Method**)mid)); 2143 } 2144 2145 Method* Method::checked_resolve_jmethod_id(jmethodID mid) { 2146 if (mid == NULL) return NULL; 2147 Method* o = resolve_jmethod_id(mid); 2148 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) { 2149 return NULL; 2150 } 2151 return o; 2152 }; 2153 2154 void Method::set_on_stack(const bool value) { 2155 // Set both the method itself and its constant pool. The constant pool 2156 // on stack means some method referring to it is also on the stack. 2157 constants()->set_on_stack(value); 2158 2159 bool already_set = on_stack(); 2160 _access_flags.set_on_stack(value); 2161 if (value && !already_set) { 2162 MetadataOnStackMark::record(this); 2163 } 2164 } 2165 2166 // Called when the class loader is unloaded to make all methods weak. 2167 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) { 2168 loader_data->jmethod_ids()->clear_all_methods(); 2169 } 2170 2171 bool Method::has_method_vptr(const void* ptr) { 2172 Method m; 2173 // This assumes that the vtbl pointer is the first word of a C++ object. 2174 return dereference_vptr(&m) == dereference_vptr(ptr); 2175 } 2176 2177 // Check that this pointer is valid by checking that the vtbl pointer matches 2178 bool Method::is_valid_method() const { 2179 if (this == NULL) { 2180 return false; 2181 } else if ((intptr_t(this) & (wordSize-1)) != 0) { 2182 // Quick sanity check on pointer. 2183 return false; 2184 } else if (is_shared()) { 2185 return MetaspaceShared::is_valid_shared_method(this); 2186 } else if (Metaspace::contains_non_shared(this)) { 2187 return has_method_vptr((const void*)this); 2188 } else { 2189 return false; 2190 } 2191 } 2192 2193 #ifndef PRODUCT 2194 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) { 2195 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods()); 2196 } 2197 #endif // PRODUCT 2198 2199 2200 // Printing 2201 2202 #ifndef PRODUCT 2203 2204 void Method::print_on(outputStream* st) const { 2205 ResourceMark rm; 2206 assert(is_method(), "must be method"); 2207 st->print_cr("%s", internal_name()); 2208 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this)); 2209 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr(); 2210 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants())); 2211 constants()->print_value_on(st); st->cr(); 2212 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr(); 2213 st->print (" - name: "); name()->print_value_on(st); st->cr(); 2214 st->print (" - signature: "); signature()->print_value_on(st); st->cr(); 2215 st->print_cr(" - max stack: %d", max_stack()); 2216 st->print_cr(" - max locals: %d", max_locals()); 2217 st->print_cr(" - size of params: %d", size_of_parameters()); 2218 st->print_cr(" - method size: %d", method_size()); 2219 if (intrinsic_id() != vmIntrinsics::_none) 2220 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id())); 2221 if (highest_comp_level() != CompLevel_none) 2222 st->print_cr(" - highest level: %d", highest_comp_level()); 2223 st->print_cr(" - vtable index: %d", _vtable_index); 2224 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry())); 2225 st->print( " - adapters: "); 2226 AdapterHandlerEntry* a = ((Method*)this)->adapter(); 2227 if (a == NULL) 2228 st->print_cr(INTPTR_FORMAT, p2i(a)); 2229 else 2230 a->print_adapter_on(st); 2231 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry())); 2232 st->print_cr(" - code size: %d", code_size()); 2233 if (code_size() != 0) { 2234 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base())); 2235 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size())); 2236 } 2237 if (method_data() != NULL) { 2238 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data())); 2239 } 2240 st->print_cr(" - checked ex length: %d", checked_exceptions_length()); 2241 if (checked_exceptions_length() > 0) { 2242 CheckedExceptionElement* table = checked_exceptions_start(); 2243 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table)); 2244 if (Verbose) { 2245 for (int i = 0; i < checked_exceptions_length(); i++) { 2246 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index)); 2247 } 2248 } 2249 } 2250 if (has_linenumber_table()) { 2251 u_char* table = compressed_linenumber_table(); 2252 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table)); 2253 if (Verbose) { 2254 CompressedLineNumberReadStream stream(table); 2255 while (stream.read_pair()) { 2256 st->print_cr(" - line %d: %d", stream.line(), stream.bci()); 2257 } 2258 } 2259 } 2260 st->print_cr(" - localvar length: %d", localvariable_table_length()); 2261 if (localvariable_table_length() > 0) { 2262 LocalVariableTableElement* table = localvariable_table_start(); 2263 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table)); 2264 if (Verbose) { 2265 for (int i = 0; i < localvariable_table_length(); i++) { 2266 int bci = table[i].start_bci; 2267 int len = table[i].length; 2268 const char* name = constants()->printable_name_at(table[i].name_cp_index); 2269 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index); 2270 int slot = table[i].slot; 2271 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot); 2272 } 2273 } 2274 } 2275 if (code() != NULL) { 2276 st->print (" - compiled code: "); 2277 code()->print_value_on(st); 2278 } 2279 if (is_native()) { 2280 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function())); 2281 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler())); 2282 } 2283 } 2284 2285 void Method::print_linkage_flags(outputStream* st) { 2286 access_flags().print_on(st); 2287 if (is_default_method()) { 2288 st->print("default "); 2289 } 2290 if (is_overpass()) { 2291 st->print("overpass "); 2292 } 2293 } 2294 #endif //PRODUCT 2295 2296 void Method::print_value_on(outputStream* st) const { 2297 assert(is_method(), "must be method"); 2298 st->print("%s", internal_name()); 2299 print_address_on(st); 2300 st->print(" "); 2301 name()->print_value_on(st); 2302 st->print(" "); 2303 signature()->print_value_on(st); 2304 st->print(" in "); 2305 method_holder()->print_value_on(st); 2306 if (WizardMode) st->print("#%d", _vtable_index); 2307 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals()); 2308 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code()); 2309 } 2310 2311 #if INCLUDE_SERVICES 2312 // Size Statistics 2313 void Method::collect_statistics(KlassSizeStats *sz) const { 2314 int mysize = sz->count(this); 2315 sz->_method_bytes += mysize; 2316 sz->_method_all_bytes += mysize; 2317 sz->_rw_bytes += mysize; 2318 2319 if (constMethod()) { 2320 constMethod()->collect_statistics(sz); 2321 } 2322 if (method_data()) { 2323 method_data()->collect_statistics(sz); 2324 } 2325 } 2326 #endif // INCLUDE_SERVICES 2327 2328 // LogTouchedMethods and PrintTouchedMethods 2329 2330 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because 2331 // the Method may be garbage collected. Let's roll our own hash table. 2332 class TouchedMethodRecord : CHeapObj<mtTracing> { 2333 public: 2334 // It's OK to store Symbols here because they will NOT be GC'ed if 2335 // LogTouchedMethods is enabled. 2336 TouchedMethodRecord* _next; 2337 Symbol* _class_name; 2338 Symbol* _method_name; 2339 Symbol* _method_signature; 2340 }; 2341 2342 static const int TOUCHED_METHOD_TABLE_SIZE = 20011; 2343 static TouchedMethodRecord** _touched_method_table = NULL; 2344 2345 void Method::log_touched(TRAPS) { 2346 2347 const int table_size = TOUCHED_METHOD_TABLE_SIZE; 2348 Symbol* my_class = klass_name(); 2349 Symbol* my_name = name(); 2350 Symbol* my_sig = signature(); 2351 2352 unsigned int hash = my_class->identity_hash() + 2353 my_name->identity_hash() + 2354 my_sig->identity_hash(); 2355 juint index = juint(hash) % table_size; 2356 2357 MutexLocker ml(TouchedMethodLog_lock, THREAD); 2358 if (_touched_method_table == NULL) { 2359 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size, 2360 mtTracing, CURRENT_PC); 2361 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size); 2362 } 2363 2364 TouchedMethodRecord* ptr = _touched_method_table[index]; 2365 while (ptr) { 2366 if (ptr->_class_name == my_class && 2367 ptr->_method_name == my_name && 2368 ptr->_method_signature == my_sig) { 2369 return; 2370 } 2371 if (ptr->_next == NULL) break; 2372 ptr = ptr->_next; 2373 } 2374 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing); 2375 my_class->set_permanent(); // prevent reclaimed by GC 2376 my_name->set_permanent(); 2377 my_sig->set_permanent(); 2378 nptr->_class_name = my_class; 2379 nptr->_method_name = my_name; 2380 nptr->_method_signature = my_sig; 2381 nptr->_next = NULL; 2382 2383 if (ptr == NULL) { 2384 // first 2385 _touched_method_table[index] = nptr; 2386 } else { 2387 ptr->_next = nptr; 2388 } 2389 } 2390 2391 void Method::print_touched_methods(outputStream* out) { 2392 MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock); 2393 out->print_cr("# Method::print_touched_methods version 1"); 2394 if (_touched_method_table) { 2395 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) { 2396 TouchedMethodRecord* ptr = _touched_method_table[i]; 2397 while(ptr) { 2398 ptr->_class_name->print_symbol_on(out); out->print("."); 2399 ptr->_method_name->print_symbol_on(out); out->print(":"); 2400 ptr->_method_signature->print_symbol_on(out); out->cr(); 2401 ptr = ptr->_next; 2402 } 2403 } 2404 } 2405 } 2406 2407 // Verification 2408 2409 void Method::verify_on(outputStream* st) { 2410 guarantee(is_method(), "object must be method"); 2411 guarantee(constants()->is_constantPool(), "should be constant pool"); 2412 guarantee(constMethod()->is_constMethod(), "should be ConstMethod*"); 2413 MethodData* md = method_data(); 2414 guarantee(md == NULL || 2415 md->is_methodData(), "should be method data"); 2416 }