1 /*
   2  * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "cds/aotMetaspace.hpp"
  26 #include "cds/cdsConfig.hpp"
  27 #include "cds/cppVtables.hpp"
  28 #include "classfile/classLoader.hpp"
  29 #include "classfile/classLoaderDataGraph.hpp"
  30 #include "classfile/metadataOnStackMark.hpp"
  31 #include "classfile/symbolTable.hpp"
  32 #include "classfile/systemDictionary.hpp"
  33 #include "classfile/vmClasses.hpp"
  34 #include "code/aotCodeCache.hpp"
  35 #include "code/codeCache.hpp"
  36 #include "code/debugInfoRec.hpp"
  37 #include "compiler/compilationPolicy.hpp"
  38 #include "gc/shared/collectedHeap.inline.hpp"
  39 #include "interpreter/bytecodes.hpp"
  40 #include "interpreter/bytecodeStream.hpp"
  41 #include "interpreter/bytecodeTracer.hpp"
  42 #include "interpreter/interpreter.hpp"
  43 #include "interpreter/oopMapCache.hpp"
  44 #include "logging/log.hpp"
  45 #include "logging/logStream.hpp"
  46 #include "logging/logTag.hpp"
  47 #include "memory/allocation.inline.hpp"
  48 #include "memory/metadataFactory.hpp"
  49 #include "memory/metaspaceClosure.hpp"
  50 #include "memory/oopFactory.hpp"
  51 #include "memory/resourceArea.hpp"
  52 #include "memory/universe.hpp"
  53 #include "nmt/memTracker.hpp"
  54 #include "oops/constantPool.hpp"
  55 #include "oops/constMethod.hpp"

  56 #include "oops/jmethodIDTable.hpp"
  57 #include "oops/klass.inline.hpp"
  58 #include "oops/method.inline.hpp"
  59 #include "oops/methodData.hpp"
  60 #include "oops/objArrayKlass.hpp"
  61 #include "oops/objArrayOop.inline.hpp"
  62 #include "oops/oop.inline.hpp"
  63 #include "oops/symbol.hpp"
  64 #include "oops/trainingData.hpp"
  65 #include "prims/jvmtiExport.hpp"
  66 #include "prims/methodHandles.hpp"
  67 #include "runtime/arguments.hpp"
  68 #include "runtime/atomicAccess.hpp"
  69 #include "runtime/continuationEntry.hpp"
  70 #include "runtime/frame.inline.hpp"
  71 #include "runtime/handles.inline.hpp"
  72 #include "runtime/init.hpp"
  73 #include "runtime/java.hpp"
  74 #include "runtime/orderAccess.hpp"
  75 #include "runtime/perfData.hpp"
  76 #include "runtime/relocator.hpp"
  77 #include "runtime/safepointVerifiers.hpp"
  78 #include "runtime/sharedRuntime.hpp"
  79 #include "runtime/signature.hpp"
  80 #include "runtime/threads.hpp"
  81 #include "runtime/vm_version.hpp"
  82 #include "utilities/align.hpp"
  83 #include "utilities/quickSort.hpp"
  84 #include "utilities/vmError.hpp"
  85 #include "utilities/xmlstream.hpp"
  86 
  87 // Implementation of Method
  88 
  89 Method* Method::allocate(ClassLoaderData* loader_data,
  90                          int byte_code_size,
  91                          AccessFlags access_flags,
  92                          InlineTableSizes* sizes,
  93                          ConstMethod::MethodType method_type,
  94                          Symbol* name,
  95                          TRAPS) {
  96   assert(!access_flags.is_native() || byte_code_size == 0,
  97          "native methods should not contain byte codes");
  98   ConstMethod* cm = ConstMethod::allocate(loader_data,
  99                                           byte_code_size,
 100                                           sizes,
 101                                           method_type,
 102                                           CHECK_NULL);
 103   int size = Method::size(access_flags.is_native());
 104   return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, name);
 105 }
 106 
 107 Method::Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name) {
 108   NoSafepointVerifier no_safepoint;
 109   set_constMethod(xconst);
 110   set_access_flags(access_flags);
 111   set_intrinsic_id(vmIntrinsics::_none);
 112   clear_method_data();
 113   clear_method_counters();
 114   set_vtable_index(Method::garbage_vtable_index);
 115 
 116   // Fix and bury in Method*
 117   set_interpreter_entry(nullptr); // sets i2i entry and from_int
 118   set_adapter_entry(nullptr);
 119   Method::clear_code(); // from_c/from_i get set to c2i/i2i
 120 
 121   if (access_flags.is_native()) {
 122     clear_native_function();
 123     set_signature_handler(nullptr);
 124   }
 125 
 126   NOT_PRODUCT(set_compiled_invocation_count(0);)
 127   // Name is very useful for debugging.
 128   NOT_PRODUCT(_name = name;)
 129 }
 130 
 131 // Release Method*.  The nmethod will be gone when we get here because
 132 // we've walked the code cache.
 133 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 134   MetadataFactory::free_metadata(loader_data, constMethod());
 135   set_constMethod(nullptr);
 136   MetadataFactory::free_metadata(loader_data, method_data());
 137   clear_method_data();
 138   MetadataFactory::free_metadata(loader_data, method_counters());
 139   clear_method_counters();
 140   set_adapter_entry(nullptr);
 141   // The nmethod will be gone when we get here.
 142   if (code() != nullptr) _code = nullptr;
 143 }
 144 
 145 void Method::release_C_heap_structures() {
 146   if (method_data()) {
 147     method_data()->release_C_heap_structures();
 148 
 149     // Destroy MethodData embedded lock
 150     method_data()->~MethodData();
 151   }
 152 }
 153 
 154 address Method::get_i2c_entry() {
 155   if (is_abstract()) {
 156     return SharedRuntime::throw_AbstractMethodError_entry();
 157   }
 158   assert(adapter() != nullptr, "must have");
 159   return adapter()->get_i2c_entry();
 160 }
 161 
 162 address Method::get_c2i_entry() {
 163   if (is_abstract()) {
 164     return SharedRuntime::get_handle_wrong_method_abstract_stub();
 165   }
 166   assert(adapter() != nullptr, "must have");
 167   return adapter()->get_c2i_entry();
 168 }
 169 





 170 address Method::get_c2i_unverified_entry() {
 171   if (is_abstract()) {
 172     return SharedRuntime::get_handle_wrong_method_abstract_stub();
 173   }
 174   assert(adapter() != nullptr, "must have");
 175   return adapter()->get_c2i_unverified_entry();
 176 }
 177 





 178 address Method::get_c2i_no_clinit_check_entry() {
 179   if (is_abstract()) {
 180     return nullptr;
 181   }
 182   assert(VM_Version::supports_fast_class_init_checks(), "");
 183   assert(adapter() != nullptr, "must have");
 184   return adapter()->get_c2i_no_clinit_check_entry();
 185 }
 186 
 187 char* Method::name_and_sig_as_C_string() const {
 188   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 189 }
 190 
 191 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 192   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 193 }
 194 
 195 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 196   const char* klass_name = klass->external_name();
 197   int klass_name_len  = (int)strlen(klass_name);
 198   int method_name_len = method_name->utf8_length();
 199   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 200   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 201   strcpy(dest, klass_name);
 202   dest[klass_name_len] = '.';
 203   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 204   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 205   dest[len] = 0;
 206   return dest;
 207 }
 208 
 209 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 210   Symbol* klass_name = klass->name();
 211   klass_name->as_klass_external_name(buf, size);
 212   int len = (int)strlen(buf);
 213 
 214   if (len < size - 1) {
 215     buf[len++] = '.';
 216 
 217     method_name->as_C_string(&(buf[len]), size - len);
 218     len = (int)strlen(buf);
 219 
 220     signature->as_C_string(&(buf[len]), size - len);
 221   }
 222 
 223   return buf;
 224 }
 225 
 226 const char* Method::external_name() const {
 227   return external_name(constants()->pool_holder(), name(), signature());
 228 }
 229 
 230 void Method::print_external_name(outputStream *os) const {
 231   print_external_name(os, constants()->pool_holder(), name(), signature());
 232 }
 233 
 234 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
 235   stringStream ss;
 236   print_external_name(&ss, klass, method_name, signature);
 237   return ss.as_string();
 238 }
 239 
 240 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
 241   signature->print_as_signature_external_return_type(os);
 242   os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
 243   signature->print_as_signature_external_parameters(os);
 244   os->print(")");
 245 }
 246 
 247 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
 248   if (log_is_enabled(Debug, exceptions)) {
 249     ResourceMark rm(THREAD);
 250     log_debug(exceptions)("Looking for catch handler for exception of type \"%s\" in method \"%s\"",
 251                           ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string());
 252   }
 253   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 254   // access exception table
 255   ExceptionTable table(mh());
 256   int length = table.length();
 257   // iterate through all entries sequentially
 258   constantPoolHandle pool(THREAD, mh->constants());
 259   for (int i = 0; i < length; i ++) {
 260     //reacquire the table in case a GC happened
 261     ExceptionTable table(mh());
 262     int beg_bci = table.start_pc(i);
 263     int end_bci = table.end_pc(i);
 264     assert(beg_bci <= end_bci, "inconsistent exception table");
 265     log_debug(exceptions)("  - checking exception table entry for BCI %d to %d",
 266                          beg_bci, end_bci);
 267 
 268     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 269       // exception handler bci range covers throw_bci => investigate further
 270       log_debug(exceptions)("    - entry covers throw point BCI %d", throw_bci);
 271 
 272       int handler_bci = table.handler_pc(i);
 273       int klass_index = table.catch_type_index(i);
 274       if (klass_index == 0) {
 275         if (log_is_enabled(Info, exceptions)) {
 276           ResourceMark rm(THREAD);
 277           log_info(exceptions)("Found catch-all handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
 278                                ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
 279         }
 280         return handler_bci;
 281       } else if (ex_klass == nullptr) {
 282         // Is this even possible?
 283         if (log_is_enabled(Info, exceptions)) {
 284           ResourceMark rm(THREAD);
 285           log_info(exceptions)("null exception class is implicitly caught by handler in method \"%s\" at BCI: %d",
 286                                mh()->name()->as_C_string(), handler_bci);
 287         }
 288         return handler_bci;
 289       } else {
 290         if (log_is_enabled(Debug, exceptions)) {
 291           ResourceMark rm(THREAD);
 292           log_debug(exceptions)("    - resolving catch type \"%s\"",
 293                                pool->klass_name_at(klass_index)->as_C_string());
 294         }
 295         // we know the exception class => get the constraint class
 296         // this may require loading of the constraint class; if verification
 297         // fails or some other exception occurs, return handler_bci
 298         Klass* k = pool->klass_at(klass_index, THREAD);
 299         if (HAS_PENDING_EXCEPTION) {
 300           if (log_is_enabled(Debug, exceptions)) {
 301             ResourceMark rm(THREAD);
 302             log_debug(exceptions)("    - exception \"%s\" occurred resolving catch type",
 303                                  PENDING_EXCEPTION->klass()->external_name());
 304           }
 305           return handler_bci;
 306         }
 307         assert(k != nullptr, "klass not loaded");
 308         if (ex_klass->is_subtype_of(k)) {
 309           if (log_is_enabled(Info, exceptions)) {
 310             ResourceMark rm(THREAD);
 311             log_info(exceptions)("Found matching handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
 312                                  ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
 313           }
 314           return handler_bci;
 315         }
 316       }
 317     }
 318   }
 319 
 320   if (log_is_enabled(Debug, exceptions)) {
 321     ResourceMark rm(THREAD);
 322     log_debug(exceptions)("No catch handler found for exception of type \"%s\" in method \"%s\"",
 323                           ex_klass->external_name(), mh->name()->as_C_string());
 324   }
 325 
 326   return -1;
 327 }
 328 
 329 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 330   methodHandle h_this(Thread::current(), this);
 331   mask_for(h_this, bci, mask);
 332 }
 333 
 334 void Method::mask_for(const methodHandle& this_mh, int bci, InterpreterOopMap* mask) {
 335   assert(this_mh() == this, "Sanity");
 336   method_holder()->mask_for(this_mh, bci, mask);
 337 }
 338 
 339 int Method::bci_from(address bcp) const {
 340   if (is_native() && bcp == nullptr) {
 341     return 0;
 342   }
 343   // Do not have a ResourceMark here because AsyncGetCallTrace stack walking code
 344   // may call this after interrupting a nested ResourceMark.
 345   assert((is_native() && bcp == code_base()) || contains(bcp) || VMError::is_error_reported(),
 346          "bcp doesn't belong to this method. bcp: " PTR_FORMAT, p2i(bcp));
 347 
 348   return int(bcp - code_base());
 349 }
 350 
 351 
 352 int Method::validate_bci(int bci) const {
 353   // Called from the verifier, and should return -1 if not valid.
 354   return ((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size())) ? bci : -1;
 355 }
 356 
 357 // Return bci if it appears to be a valid bcp
 358 // Return -1 otherwise.
 359 // Used by profiling code, when invalid data is a possibility.
 360 // The caller is responsible for validating the Method* itself.
 361 int Method::validate_bci_from_bcp(address bcp) const {
 362   // keep bci as -1 if not a valid bci
 363   int bci = -1;
 364   if (bcp == nullptr || bcp == code_base()) {
 365     // code_size() may return 0 and we allow 0 here
 366     // the method may be native
 367     bci = 0;
 368   } else if (contains(bcp)) {
 369     bci = int(bcp - code_base());
 370   }
 371   // Assert that if we have dodged any asserts, bci is negative.
 372   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 373   return bci;
 374 }
 375 
 376 address Method::bcp_from(int bci) const {
 377   assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
 378          "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
 379   address bcp = code_base() + bci;
 380   assert((is_native() && bcp == code_base()) || contains(bcp), "bcp doesn't belong to this method");
 381   return bcp;
 382 }
 383 
 384 address Method::bcp_from(address bcp) const {
 385   if (is_native() && bcp == nullptr) {
 386     return code_base();
 387   } else {
 388     return bcp;
 389   }
 390 }
 391 
 392 int Method::size(bool is_native) {
 393   // If native, then include pointers for native_function and signature_handler
 394   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 395   int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
 396   return align_metadata_size(header_size() + extra_words);
 397 }
 398 
 399 Symbol* Method::klass_name() const {
 400   return method_holder()->name();
 401 }
 402 
 403 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
 404   log_trace(aot)("Iter(Method): %p", this);
 405 
 406   if (!method_holder()->is_rewritten()) {
 407     it->push(&_constMethod, MetaspaceClosure::_writable);
 408   } else {
 409     it->push(&_constMethod);
 410   }
 411   it->push(&_adapter);
 412   it->push(&_method_data);
 413   it->push(&_method_counters);
 414   NOT_PRODUCT(it->push(&_name);)
 415 }
 416 
 417 #if INCLUDE_CDS
 418 // Attempt to return method to original state.  Clear any pointers
 419 // (to objects outside the shared spaces).  We won't be able to predict
 420 // where they should point in a new JVM.  Further initialize some
 421 // entries now in order allow them to be write protected later.
 422 
 423 void Method::remove_unshareable_info() {
 424   unlink_method();
 425   if (method_data() != nullptr) {
 426     method_data()->remove_unshareable_info();
 427   }
 428   if (method_counters() != nullptr) {
 429     method_counters()->remove_unshareable_info();
 430   }
 431   if (CDSConfig::is_dumping_adapters() && _adapter != nullptr) {
 432     _adapter->remove_unshareable_info();
 433     _adapter = nullptr;
 434   }
 435   JFR_ONLY(REMOVE_METHOD_ID(this);)
 436 }
 437 
 438 void Method::restore_unshareable_info(TRAPS) {
 439   assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
 440   if (method_data() != nullptr) {
 441     method_data()->restore_unshareable_info(CHECK);
 442   }
 443   if (method_counters() != nullptr) {
 444     method_counters()->restore_unshareable_info(CHECK);
 445   }
 446   if (_adapter != nullptr) {
 447     assert(_adapter->is_linked(), "must be");
 448     _from_compiled_entry = _adapter->get_c2i_entry();


 449   }
 450   assert(!queued_for_compilation(), "method's queued_for_compilation flag should not be set");
 451 }
 452 #endif
 453 
 454 void Method::set_vtable_index(int index) {
 455   if (in_aot_cache() && !AOTMetaspace::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
 456     // At runtime initialize_vtable is rerun as part of link_class_impl()
 457     // for a shared class loaded by the non-boot loader to obtain the loader
 458     // constraints based on the runtime classloaders' context.
 459     return; // don't write into the shared class
 460   } else {
 461     _vtable_index = index;
 462   }
 463 }
 464 
 465 void Method::set_itable_index(int index) {
 466   if (in_aot_cache() && !AOTMetaspace::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
 467     // At runtime initialize_itable is rerun as part of link_class_impl()
 468     // for a shared class loaded by the non-boot loader to obtain the loader
 469     // constraints based on the runtime classloaders' context. The dumptime
 470     // itable index should be the same as the runtime index.
 471     assert(_vtable_index == itable_index_max - index,
 472            "archived itable index is different from runtime index");
 473     return; // don't write into the shared class
 474   } else {
 475     _vtable_index = itable_index_max - index;
 476   }
 477   assert(valid_itable_index(), "");
 478 }
 479 
 480 // The RegisterNatives call being attempted tried to register with a method that
 481 // is not native.  Ask JVM TI what prefixes have been specified.  Then check
 482 // to see if the native method is now wrapped with the prefixes.  See the
 483 // SetNativeMethodPrefix(es) functions in the JVM TI Spec for details.
 484 static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS) {
 485 #if INCLUDE_JVMTI
 486   ResourceMark rm(THREAD);
 487   Method* method;
 488   int name_len = name->utf8_length();
 489   char* name_str = name->as_utf8();
 490   int prefix_count;
 491   char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
 492   for (int i = 0; i < prefix_count; i++) {
 493     char* prefix = prefixes[i];
 494     int prefix_len = (int)strlen(prefix);
 495 
 496     // try adding this prefix to the method name and see if it matches another method name
 497     int trial_len = name_len + prefix_len;
 498     char* trial_name_str = NEW_RESOURCE_ARRAY(char, trial_len + 1);
 499     strcpy(trial_name_str, prefix);
 500     strcat(trial_name_str, name_str);
 501     TempNewSymbol trial_name = SymbolTable::probe(trial_name_str, trial_len);
 502     if (trial_name == nullptr) {
 503       continue; // no such symbol, so this prefix wasn't used, try the next prefix
 504     }
 505     method = k->lookup_method(trial_name, signature);
 506     if (method == nullptr) {
 507       continue; // signature doesn't match, try the next prefix
 508     }
 509     if (method->is_native()) {
 510       method->set_is_prefixed_native();
 511       return method; // wahoo, we found a prefixed version of the method, return it
 512     }
 513     // found as non-native, so prefix is good, add it, probably just need more prefixes
 514     name_len = trial_len;
 515     name_str = trial_name_str;
 516   }
 517 #endif // INCLUDE_JVMTI
 518   return nullptr; // not found
 519 }
 520 
 521 bool Method::register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS) {
 522   Method* method = k->lookup_method(name, signature);
 523   if (method == nullptr) {
 524     ResourceMark rm(THREAD);
 525     stringStream st;
 526     st.print("Method '");
 527     print_external_name(&st, k, name, signature);
 528     st.print("' name or signature does not match");
 529     THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
 530   }
 531   if (!method->is_native()) {
 532     // trying to register to a non-native method, see if a JVM TI agent has added prefix(es)
 533     method = find_prefixed_native(k, name, signature, THREAD);
 534     if (method == nullptr) {
 535       ResourceMark rm(THREAD);
 536       stringStream st;
 537       st.print("Method '");
 538       print_external_name(&st, k, name, signature);
 539       st.print("' is not declared as native");
 540       THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
 541     }
 542   }
 543 
 544   if (entry != nullptr) {
 545     method->set_native_function(entry, native_bind_event_is_interesting);
 546   } else {
 547     method->clear_native_function();
 548   }
 549   if (log_is_enabled(Debug, jni, resolve)) {
 550     ResourceMark rm(THREAD);
 551     log_debug(jni, resolve)("[Registering JNI native method %s.%s]",
 552                             method->method_holder()->external_name(),
 553                             method->name()->as_C_string());
 554   }
 555   return true;
 556 }
 557 
 558 bool Method::was_executed_more_than(int n) {
 559   // Invocation counter is reset when the Method* is compiled.
 560   // If the method has compiled code we therefore assume it has
 561   // be executed more than n times.
 562   if (is_accessor() || is_empty_method() || (code() != nullptr)) {
 563     // interpreter doesn't bump invocation counter of trivial methods
 564     // compiler does not bump invocation counter of compiled methods
 565     return true;
 566   }
 567   else if ((method_counters() != nullptr &&
 568             method_counters()->invocation_counter()->carry()) ||
 569            (method_data() != nullptr &&
 570             method_data()->invocation_counter()->carry())) {
 571     // The carry bit is set when the counter overflows and causes
 572     // a compilation to occur.  We don't know how many times
 573     // the counter has been reset, so we simply assume it has
 574     // been executed more than n times.
 575     return true;
 576   } else {
 577     return invocation_count() > n;
 578   }
 579 }
 580 
 581 void Method::print_invocation_count(outputStream* st) {
 582   //---<  compose+print method return type, klass, name, and signature  >---
 583   if (is_static())       { st->print("static "); }
 584   if (is_final())        { st->print("final "); }
 585   if (is_synchronized()) { st->print("synchronized "); }
 586   if (is_native())       { st->print("native "); }
 587   st->print("%s::", method_holder()->external_name());
 588   name()->print_symbol_on(st);
 589   signature()->print_symbol_on(st);
 590 
 591   if (WizardMode) {
 592     // dump the size of the byte codes
 593     st->print(" {%d}", code_size());
 594   }
 595   st->cr();
 596 
 597   // Counting based on signed int counters tends to overflow with
 598   // longer-running workloads on fast machines. The counters under
 599   // consideration here, however, are limited in range by counting
 600   // logic. See InvocationCounter:count_limit for example.
 601   // No "overflow precautions" need to be implemented here.
 602   st->print_cr ("  interpreter_invocation_count: " INT32_FORMAT_W(11), interpreter_invocation_count());
 603   st->print_cr ("  invocation_counter:           " INT32_FORMAT_W(11), invocation_count());
 604   st->print_cr ("  backedge_counter:             " INT32_FORMAT_W(11), backedge_count());
 605 
 606   if (method_data() != nullptr) {
 607     st->print_cr ("  decompile_count:              " UINT32_FORMAT_W(11), method_data()->decompile_count());
 608   }
 609 
 610 #ifndef PRODUCT
 611   if (CountCompiledCalls) {
 612     st->print_cr ("  compiled_invocation_count:    " INT64_FORMAT_W(11), compiled_invocation_count());
 613   }
 614 #endif
 615 }
 616 
 617 MethodTrainingData* Method::training_data_or_null() const {
 618   MethodCounters* mcs = method_counters();
 619   if (mcs == nullptr) {
 620     return nullptr;
 621   } else {
 622     MethodTrainingData* mtd = mcs->method_training_data();
 623     if (mtd == mcs->method_training_data_sentinel()) {
 624       return nullptr;
 625     }
 626     return mtd;
 627   }
 628 }
 629 
 630 bool Method::init_training_data(MethodTrainingData* td) {
 631   MethodCounters* mcs = method_counters();
 632   if (mcs == nullptr) {
 633     return false;
 634   } else {
 635     return mcs->init_method_training_data(td);
 636   }
 637 }
 638 
 639 bool Method::install_training_method_data(const methodHandle& method) {
 640   MethodTrainingData* mtd = MethodTrainingData::find(method);
 641   if (mtd != nullptr && mtd->final_profile() != nullptr) {
 642     AtomicAccess::replace_if_null(&method->_method_data, mtd->final_profile());
 643     return true;
 644   }
 645   return false;
 646 }
 647 
 648 // Build a MethodData* object to hold profiling information collected on this
 649 // method when requested.
 650 void Method::build_profiling_method_data(const methodHandle& method, TRAPS) {
 651   if (install_training_method_data(method)) {
 652     return;
 653   }
 654   // Do not profile the method if metaspace has hit an OOM previously
 655   // allocating profiling data. Callers clear pending exception so don't
 656   // add one here.
 657   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 658     return;
 659   }
 660 
 661   ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 662   MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 663   if (HAS_PENDING_EXCEPTION) {
 664     CompileBroker::log_metaspace_failure();
 665     ClassLoaderDataGraph::set_metaspace_oom(true);
 666     return;   // return the exception (which is cleared)
 667   }
 668 
 669   if (!AtomicAccess::replace_if_null(&method->_method_data, method_data)) {
 670     MetadataFactory::free_metadata(loader_data, method_data);
 671     return;
 672   }
 673 
 674   if (PrintMethodData && (Verbose || WizardMode)) {
 675     ResourceMark rm(THREAD);
 676     tty->print("build_profiling_method_data for ");
 677     method->print_name(tty);
 678     tty->cr();
 679     // At the end of the run, the MDO, full of data, will be dumped.
 680   }
 681 }
 682 
 683 MethodCounters* Method::build_method_counters(Thread* current, Method* m) {
 684   // Do not profile the method if metaspace has hit an OOM previously
 685   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 686     return nullptr;
 687   }
 688 
 689   methodHandle mh(current, m);
 690   MethodCounters* counters;
 691   if (current->is_Java_thread()) {
 692     JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
 693     // Use the TRAPS version for a JavaThread so it will adjust the GC threshold
 694     // if needed.
 695     counters = MethodCounters::allocate_with_exception(mh, THREAD);
 696     if (HAS_PENDING_EXCEPTION) {
 697       CLEAR_PENDING_EXCEPTION;
 698     }
 699   } else {
 700     // Call metaspace allocation that doesn't throw exception if the
 701     // current thread isn't a JavaThread, ie. the VMThread.
 702     counters = MethodCounters::allocate_no_exception(mh);
 703   }
 704 
 705   if (counters == nullptr) {
 706     CompileBroker::log_metaspace_failure();
 707     ClassLoaderDataGraph::set_metaspace_oom(true);
 708     return nullptr;
 709   }
 710 
 711   if (!mh->init_method_counters(counters)) {
 712     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 713   }
 714 
 715   return mh->method_counters();
 716 }
 717 
 718 bool Method::init_method_counters(MethodCounters* counters) {
 719   // Try to install a pointer to MethodCounters, return true on success.
 720   return AtomicAccess::replace_if_null(&_method_counters, counters);
 721 }
 722 
 723 void Method::set_exception_handler_entered(int handler_bci) {
 724   if (ProfileExceptionHandlers) {
 725     MethodData* mdo = method_data();
 726     if (mdo != nullptr) {
 727       BitData handler_data = mdo->exception_handler_bci_to_data(handler_bci);
 728       handler_data.set_exception_handler_entered();
 729     }
 730   }
 731 }
 732 
 733 int Method::extra_stack_words() {
 734   // not an inline function, to avoid a header dependency on Interpreter
 735   return extra_stack_entries() * Interpreter::stackElementSize;
 736 }
 737 














 738 bool Method::compute_has_loops_flag() {
 739   BytecodeStream bcs(methodHandle(Thread::current(), this));
 740   Bytecodes::Code bc;
 741 
 742   while ((bc = bcs.next()) >= 0) {
 743     switch (bc) {
 744       case Bytecodes::_ifeq:
 745       case Bytecodes::_ifnull:
 746       case Bytecodes::_iflt:
 747       case Bytecodes::_ifle:
 748       case Bytecodes::_ifne:
 749       case Bytecodes::_ifnonnull:
 750       case Bytecodes::_ifgt:
 751       case Bytecodes::_ifge:
 752       case Bytecodes::_if_icmpeq:
 753       case Bytecodes::_if_icmpne:
 754       case Bytecodes::_if_icmplt:
 755       case Bytecodes::_if_icmpgt:
 756       case Bytecodes::_if_icmple:
 757       case Bytecodes::_if_icmpge:
 758       case Bytecodes::_if_acmpeq:
 759       case Bytecodes::_if_acmpne:
 760       case Bytecodes::_goto:
 761       case Bytecodes::_jsr:
 762         if (bcs.dest() < bcs.next_bci()) {
 763           return set_has_loops();
 764         }
 765         break;
 766 
 767       case Bytecodes::_goto_w:
 768       case Bytecodes::_jsr_w:
 769         if (bcs.dest_w() < bcs.next_bci()) {
 770           return set_has_loops();
 771         }
 772         break;
 773 
 774       case Bytecodes::_lookupswitch: {
 775         Bytecode_lookupswitch lookupswitch(this, bcs.bcp());
 776         if (lookupswitch.default_offset() < 0) {
 777           return set_has_loops();
 778         } else {
 779           for (int i = 0; i < lookupswitch.number_of_pairs(); ++i) {
 780             LookupswitchPair pair = lookupswitch.pair_at(i);
 781             if (pair.offset() < 0) {
 782               return set_has_loops();
 783             }
 784           }
 785         }
 786         break;
 787       }
 788       case Bytecodes::_tableswitch: {
 789         Bytecode_tableswitch tableswitch(this, bcs.bcp());
 790         if (tableswitch.default_offset() < 0) {
 791           return set_has_loops();
 792         } else {
 793           for (int i = 0; i < tableswitch.length(); ++i) {
 794             if (tableswitch.dest_offset_at(i) < 0) {
 795               return set_has_loops();
 796             }
 797           }
 798         }
 799         break;
 800       }
 801       default:
 802         break;
 803     }
 804   }
 805 
 806   _flags.set_has_loops_flag_init(true);
 807   return false;
 808 }
 809 
 810 bool Method::is_final_method(AccessFlags class_access_flags) const {
 811   // or "does_not_require_vtable_entry"
 812   // default method or overpass can occur, is not final (reuses vtable entry)
 813   // private methods in classes get vtable entries for backward class compatibility.
 814   if (is_overpass() || is_default_method())  return false;
 815   return is_final() || class_access_flags.is_final();
 816 }
 817 
 818 bool Method::is_final_method() const {
 819   return is_final_method(method_holder()->access_flags());
 820 }
 821 
 822 bool Method::is_default_method() const {
 823   if (method_holder() != nullptr &&
 824       method_holder()->is_interface() &&
 825       !is_abstract() && !is_private()) {
 826     return true;
 827   } else {
 828     return false;
 829   }
 830 }
 831 
 832 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 833   if (is_final_method(class_access_flags))  return true;
 834 #ifdef ASSERT
 835   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 836   if (class_access_flags.is_interface()) {
 837       ResourceMark rm;
 838       assert(is_nonv == is_static() || is_nonv == is_private(),
 839              "nonvirtual unexpected for non-static, non-private: %s",
 840              name_and_sig_as_C_string());
 841   }
 842 #endif
 843   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 844   return vtable_index() == nonvirtual_vtable_index;
 845 }
 846 
 847 bool Method::can_be_statically_bound() const {
 848   return can_be_statically_bound(method_holder()->access_flags());
 849 }
 850 
 851 bool Method::can_be_statically_bound(InstanceKlass* context) const {
 852   return (method_holder() == context) && can_be_statically_bound();
 853 }
 854 
 855 /**
 856  *  Returns false if this is one of specially treated methods for
 857  *  which we have to provide stack trace in throw in compiled code.
 858  *  Returns true otherwise.
 859  */
 860 bool Method::can_omit_stack_trace() {
 861   if (klass_name() == vmSymbols::sun_invoke_util_ValueConversions()) {
 862     return false; // All methods in sun.invoke.util.ValueConversions
 863   }
 864   return true;
 865 }
 866 
 867 bool Method::is_accessor() const {
 868   return is_getter() || is_setter();
 869 }
 870 
 871 bool Method::is_getter() const {
 872   if (code_size() != 5) return false;
 873   if (size_of_parameters() != 1) return false;
 874   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 875   if (java_code_at(1) != Bytecodes::_getfield) return false;
 876   switch (java_code_at(4)) {
 877     case Bytecodes::_ireturn:
 878     case Bytecodes::_lreturn:
 879     case Bytecodes::_freturn:
 880     case Bytecodes::_dreturn:
 881     case Bytecodes::_areturn:
 882       break;
 883     default:
 884       return false;
 885   }





 886   return true;
 887 }
 888 
 889 bool Method::is_setter() const {
 890   if (code_size() != 6) return false;
 891   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 892   switch (java_code_at(1)) {
 893     case Bytecodes::_iload_1:
 894     case Bytecodes::_aload_1:
 895     case Bytecodes::_fload_1:
 896       if (size_of_parameters() != 2) return false;
 897       break;
 898     case Bytecodes::_dload_1:
 899     case Bytecodes::_lload_1:
 900       if (size_of_parameters() != 3) return false;
 901       break;
 902     default:
 903       return false;
 904   }
 905   if (java_code_at(2) != Bytecodes::_putfield) return false;
 906   if (java_code_at(5) != Bytecodes::_return)   return false;





 907   return true;
 908 }
 909 
 910 bool Method::is_constant_getter() const {
 911   int last_index = code_size() - 1;
 912   // Check if the first 1-3 bytecodes are a constant push
 913   // and the last bytecode is a return.
 914   return (2 <= code_size() && code_size() <= 4 &&
 915           Bytecodes::is_const(java_code_at(0)) &&
 916           Bytecodes::length_for(java_code_at(0)) == last_index &&
 917           Bytecodes::is_return(java_code_at(last_index)));
 918 }
 919 
 920 bool Method::has_valid_initializer_flags() const {
 921   return (is_static() ||
 922           method_holder()->major_version() < 51);
 923 }
 924 
 925 bool Method::is_static_initializer() const {
 926   // For classfiles version 51 or greater, ensure that the clinit method is
 927   // static.  Non-static methods with the name "<clinit>" are not static
 928   // initializers. (older classfiles exempted for backward compatibility)
 929   return name() == vmSymbols::class_initializer_name() &&
 930          has_valid_initializer_flags();

 931 }
 932 
 933 bool Method::is_object_initializer() const {
 934    return name() == vmSymbols::object_initializer_name();

 935 }
 936 
 937 bool Method::needs_clinit_barrier() const {
 938   return is_static() && !method_holder()->is_initialized();
 939 }
 940 
 941 bool Method::is_object_wait0() const {
 942   return klass_name() == vmSymbols::java_lang_Object()
 943          && name() == vmSymbols::wait_name();
 944 }
 945 
 946 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 947   int length = method->checked_exceptions_length();
 948   if (length == 0) {  // common case
 949     return objArrayHandle(THREAD, Universe::the_empty_class_array());
 950   } else {
 951     methodHandle h_this(THREAD, method);
 952     objArrayOop m_oop = oopFactory::new_objArray(vmClasses::Class_klass(), length, CHECK_(objArrayHandle()));
 953     objArrayHandle mirrors (THREAD, m_oop);
 954     for (int i = 0; i < length; i++) {
 955       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 956       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 957       if (log_is_enabled(Warning, exceptions) &&
 958           !k->is_subclass_of(vmClasses::Throwable_klass())) {
 959         ResourceMark rm(THREAD);
 960         log_warning(exceptions)(
 961           "Class %s in throws clause of method %s is not a subtype of class java.lang.Throwable",
 962           k->external_name(), method->external_name());
 963       }
 964       mirrors->obj_at_put(i, k->java_mirror());
 965     }
 966     return mirrors;
 967   }
 968 };
 969 
 970 
 971 int Method::line_number_from_bci(int bci) const {
 972   int best_bci  =  0;
 973   int best_line = -1;
 974   if (bci == SynchronizationEntryBCI) bci = 0;
 975   if (0 <= bci && bci < code_size() && has_linenumber_table()) {
 976     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 977     // Not necessarily sorted and not necessarily one-to-one.
 978     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 979     while (stream.read_pair()) {
 980       if (stream.bci() == bci) {
 981         // perfect match
 982         return stream.line();
 983       } else {
 984         // update best_bci/line
 985         if (stream.bci() < bci && stream.bci() >= best_bci) {
 986           best_bci  = stream.bci();
 987           best_line = stream.line();
 988         }
 989       }
 990     }
 991   }
 992   return best_line;
 993 }
 994 
 995 
 996 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 997   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 998     Thread *thread = Thread::current();
 999     Symbol* klass_name = constants()->klass_name_at(klass_index);
1000     Handle loader(thread, method_holder()->class_loader());
1001     return SystemDictionary::find_instance_klass(thread, klass_name, loader) != nullptr;
1002   } else {
1003     return true;
1004   }
1005 }
1006 
1007 
1008 bool Method::is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved) const {
1009   int klass_index = constants()->klass_ref_index_at(refinfo_index, bc);
1010   if (must_be_resolved) {
1011     // Make sure klass is resolved in constantpool.
1012     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;


1013   }
1014   return is_klass_loaded_by_klass_index(klass_index);
1015 }
1016 
1017 
1018 void Method::set_native_function(address function, bool post_event_flag) {
1019   assert(function != nullptr, "use clear_native_function to unregister natives");
1020   assert(!is_special_native_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
1021   address* native_function = native_function_addr();
1022 
1023   // We can see racers trying to place the same native function into place. Once
1024   // is plenty.
1025   address current = *native_function;
1026   if (current == function) return;
1027   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
1028       function != nullptr) {
1029     // native_method_throw_unsatisfied_link_error_entry() should only
1030     // be passed when post_event_flag is false.
1031     assert(function !=
1032       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1033       "post_event_flag mismatch");
1034 
1035     // post the bind event, and possible change the bind function
1036     JvmtiExport::post_native_method_bind(this, &function);
1037   }
1038   *native_function = function;
1039   // This function can be called more than once. We must make sure that we always
1040   // use the latest registered method -> check if a stub already has been generated.
1041   // If so, we have to make it not_entrant.
1042   nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
1043   if (nm != nullptr) {
1044     nm->make_not_entrant(nmethod::InvalidationReason::SET_NATIVE_FUNCTION);
1045   }
1046 }
1047 
1048 
1049 bool Method::has_native_function() const {
1050   if (is_special_native_intrinsic())
1051     return false;  // special-cased in SharedRuntime::generate_native_wrapper
1052   address func = native_function();
1053   return (func != nullptr && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
1054 }
1055 
1056 
1057 void Method::clear_native_function() {
1058   // Note: is_method_handle_intrinsic() is allowed here.
1059   set_native_function(
1060     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1061     !native_bind_event_is_interesting);
1062   this->unlink_code();
1063 }
1064 
1065 
1066 void Method::set_signature_handler(address handler) {
1067   address* signature_handler =  signature_handler_addr();
1068   *signature_handler = handler;
1069 }
1070 
1071 
1072 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
1073   assert(reason != nullptr, "must provide a reason");
1074   if (PrintCompilation && report) {
1075     ttyLocker ttyl;
1076     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
1077     if (comp_level == CompLevel_all) {
1078       tty->print("all levels ");
1079     } else {
1080       tty->print("level %d ", comp_level);
1081     }
1082     this->print_short_name(tty);
1083     int size = this->code_size();
1084     if (size > 0) {
1085       tty->print(" (%d bytes)", size);
1086     }
1087     if (reason != nullptr) {
1088       tty->print("   %s", reason);
1089     }
1090     tty->cr();
1091   }
1092   if ((TraceDeoptimization || LogCompilation) && (xtty != nullptr)) {
1093     ttyLocker ttyl;
1094     xtty->begin_elem("make_not_compilable thread='%zu' osr='%d' level='%d'",
1095                      os::current_thread_id(), is_osr, comp_level);
1096     if (reason != nullptr) {
1097       xtty->print(" reason=\'%s\'", reason);
1098     }
1099     xtty->method(this);
1100     xtty->stamp();
1101     xtty->end_elem();
1102   }
1103 }
1104 
1105 bool Method::is_always_compilable() const {
1106   // Generated adapters must be compiled
1107   if (is_special_native_intrinsic() && is_synthetic()) {
1108     assert(!is_not_c1_compilable(), "sanity check");
1109     assert(!is_not_c2_compilable(), "sanity check");
1110     return true;
1111   }
1112 
1113   return false;
1114 }
1115 
1116 bool Method::is_not_compilable(int comp_level) const {
1117   if (number_of_breakpoints() > 0)
1118     return true;
1119   if (is_always_compilable())
1120     return false;
1121   if (comp_level == CompLevel_any)
1122     return is_not_c1_compilable() && is_not_c2_compilable();
1123   if (is_c1_compile(comp_level))
1124     return is_not_c1_compilable();
1125   if (is_c2_compile(comp_level))
1126     return is_not_c2_compilable();
1127   return false;
1128 }
1129 
1130 // call this when compiler finds that this method is not compilable
1131 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
1132   if (is_always_compilable()) {
1133     // Don't mark a method which should be always compilable
1134     return;
1135   }
1136   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
1137   if (comp_level == CompLevel_all) {
1138     set_is_not_c1_compilable();
1139     set_is_not_c2_compilable();
1140   } else {
1141     if (is_c1_compile(comp_level))
1142       set_is_not_c1_compilable();
1143     if (is_c2_compile(comp_level))
1144       set_is_not_c2_compilable();
1145   }
1146   assert(!CompilationPolicy::can_be_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1147 }
1148 
1149 bool Method::is_not_osr_compilable(int comp_level) const {
1150   if (is_not_compilable(comp_level))
1151     return true;
1152   if (comp_level == CompLevel_any)
1153     return is_not_c1_osr_compilable() && is_not_c2_osr_compilable();
1154   if (is_c1_compile(comp_level))
1155     return is_not_c1_osr_compilable();
1156   if (is_c2_compile(comp_level))
1157     return is_not_c2_osr_compilable();
1158   return false;
1159 }
1160 
1161 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
1162   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
1163   if (comp_level == CompLevel_all) {
1164     set_is_not_c1_osr_compilable();
1165     set_is_not_c2_osr_compilable();
1166   } else {
1167     if (is_c1_compile(comp_level))
1168       set_is_not_c1_osr_compilable();
1169     if (is_c2_compile(comp_level))
1170       set_is_not_c2_osr_compilable();
1171   }
1172   assert(!CompilationPolicy::can_be_osr_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1173 }
1174 
1175 // Revert to using the interpreter and clear out the nmethod
1176 void Method::clear_code() {
1177   // this may be null if c2i adapters have not been made yet
1178   // Only should happen at allocate time.
1179   if (adapter() == nullptr) {
1180     _from_compiled_entry = nullptr;


1181   } else {
1182     _from_compiled_entry = adapter()->get_c2i_entry();


1183   }
1184   OrderAccess::storestore();
1185   _from_interpreted_entry = _i2i_entry;
1186   OrderAccess::storestore();
1187   _code = nullptr;
1188 }
1189 
1190 void Method::unlink_code(nmethod *compare) {
1191   ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1192   // We need to check if either the _code or _from_compiled_code_entry_point
1193   // refer to this nmethod because there is a race in setting these two fields
1194   // in Method* as seen in bugid 4947125.
1195   if (code() == compare ||
1196       from_compiled_entry() == compare->verified_entry_point()) {
1197     clear_code();
1198   }
1199 }
1200 
1201 void Method::unlink_code() {
1202   ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1203   clear_code();
1204 }
1205 
1206 #if INCLUDE_CDS
1207 // Called by class data sharing to remove any entry points (which are not shared)
1208 void Method::unlink_method() {
1209   assert(CDSConfig::is_dumping_archive(), "sanity");
1210   _code = nullptr;
1211   if (!CDSConfig::is_dumping_adapters()) {
1212     _adapter = nullptr;
1213   }
1214   _i2i_entry = nullptr;
1215   _from_compiled_entry = nullptr;


1216   _from_interpreted_entry = nullptr;
1217 
1218   if (is_native()) {
1219     *native_function_addr() = nullptr;
1220     set_signature_handler(nullptr);
1221   }
1222   NOT_PRODUCT(set_compiled_invocation_count(0);)
1223 
1224   clear_method_data();
1225   clear_method_counters();
1226   clear_is_not_c1_compilable();
1227   clear_is_not_c1_osr_compilable();
1228   clear_is_not_c2_compilable();
1229   clear_is_not_c2_osr_compilable();
1230   clear_queued_for_compilation();
1231 
1232   remove_unshareable_flags();
1233 }
1234 
1235 void Method::remove_unshareable_flags() {
1236   // clear all the flags that shouldn't be in the archived version
1237   assert(!is_old(), "must be");
1238   assert(!is_obsolete(), "must be");
1239   assert(!is_deleted(), "must be");
1240 
1241   set_is_prefixed_native(false);
1242   set_queued_for_compilation(false);
1243   set_is_not_c2_compilable(false);
1244   set_is_not_c1_compilable(false);
1245   set_is_not_c2_osr_compilable(false);
1246   set_on_stack_flag(false);


1247 }
1248 #endif
1249 
1250 // Called when the method_holder is getting linked. Setup entrypoints so the method
1251 // is ready to be called from interpreter, compiler, and vtables.
1252 void Method::link_method(const methodHandle& h_method, TRAPS) {
1253   if (log_is_enabled(Info, perf, class, link)) {
1254     ClassLoader::perf_ik_link_methods_count()->inc();
1255   }
1256 
1257   // If the code cache is full, we may reenter this function for the
1258   // leftover methods that weren't linked.
1259   if (adapter() != nullptr) {
1260     if (adapter()->in_aot_cache()) {
1261       assert(adapter()->is_linked(), "Adapter is shared but not linked");
1262     } else {
1263       return;
1264     }
1265   }
1266   assert( _code == nullptr, "nothing compiled yet" );
1267 
1268   // Setup interpreter entrypoint
1269   assert(this == h_method(), "wrong h_method()" );
1270 
1271   assert(adapter() == nullptr || adapter()->is_linked(), "init'd to null or restored from cache");
1272   address entry = Interpreter::entry_for_method(h_method);
1273   assert(entry != nullptr, "interpreter entry must be non-null");
1274   // Sets both _i2i_entry and _from_interpreted_entry
1275   set_interpreter_entry(entry);
1276 
1277   // Don't overwrite already registered native entries.
1278   if (is_native() && !has_native_function()) {
1279     set_native_function(
1280       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1281       !native_bind_event_is_interesting);
1282   }



1283 
1284   // Setup compiler entrypoint.  This is made eagerly, so we do not need
1285   // special handling of vtables.  An alternative is to make adapters more
1286   // lazily by calling make_adapter() from from_compiled_entry() for the
1287   // normal calls.  For vtable calls life gets more complicated.  When a
1288   // call-site goes mega-morphic we need adapters in all methods which can be
1289   // called from the vtable.  We need adapters on such methods that get loaded
1290   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
1291   // problem we'll make these lazily later.
1292   if (is_abstract()) {
1293     h_method->_from_compiled_entry = SharedRuntime::get_handle_wrong_method_abstract_stub();



1294   } else if (_adapter == nullptr) {
1295     (void) make_adapters(h_method, CHECK);
1296 #ifndef ZERO
1297     assert(adapter()->is_linked(), "Adapter must have been linked");
1298 #endif
1299     h_method->_from_compiled_entry = adapter()->get_c2i_entry();


1300   }
1301 
1302   // ONLY USE the h_method now as make_adapter may have blocked
1303 
1304   if (h_method->is_continuation_native_intrinsic()) {
1305     _from_interpreted_entry = nullptr;
1306     _from_compiled_entry = nullptr;
1307     _i2i_entry = nullptr;
1308     if (Continuations::enabled()) {
1309       assert(!Threads::is_vm_complete(), "should only be called during vm init");
1310       AdapterHandlerLibrary::create_native_wrapper(h_method);
1311       if (!h_method->has_compiled_code()) {
1312         THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), "Initial size of CodeCache is too small");
1313       }
1314       assert(_from_interpreted_entry == get_i2c_entry(), "invariant");
1315     }
1316   }
1317 }
1318 
1319 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1320   assert(!mh->is_abstract(), "abstract methods do not have adapters");
1321   PerfTraceTime timer(ClassLoader::perf_method_adapters_time());
1322 
1323   // Adapters for compiled code are made eagerly here.  They are fairly
1324   // small (generally < 100 bytes) and quick to make (and cached and shared)
1325   // so making them eagerly shouldn't be too expensive.
1326   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1327   if (adapter == nullptr ) {
1328     if (!is_init_completed()) {
1329       // Don't throw exceptions during VM initialization because java.lang.* classes
1330       // might not have been initialized, causing problems when constructing the
1331       // Java exception object.
1332       vm_exit_during_initialization("Out of space in CodeCache for adapters");
1333     } else {
1334       THROW_MSG_NULL(vmSymbols::java_lang_OutOfMemoryError(), "Out of space in CodeCache for adapters");
1335     }
1336   }
1337 


1338   mh->set_adapter_entry(adapter);
1339   return adapter->get_c2i_entry();
1340 }
1341 
1342 // The verified_code_entry() must be called when a invoke is resolved
1343 // on this method.
1344 
1345 // It returns the compiled code entry point, after asserting not null.
1346 // This function is called after potential safepoints so that nmethod
1347 // or adapter that it points to is still live and valid.
1348 // This function must not hit a safepoint!
1349 address Method::verified_code_entry() {
1350   DEBUG_ONLY(NoSafepointVerifier nsv;)
1351   assert(_from_compiled_entry != nullptr, "must be set");
1352   return _from_compiled_entry;
1353 }
1354 












1355 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1356 // (could be racing a deopt).
1357 // Not inline to avoid circular ref.
1358 bool Method::check_code() const {
1359   // cached in a register or local.  There's a race on the value of the field.
1360   nmethod *code = AtomicAccess::load_acquire(&_code);
1361   return code == nullptr || (code->method() == nullptr) || (code->method() == (Method*)this && !code->is_osr_method());
1362 }
1363 
1364 // Install compiled code.  Instantly it can execute.
1365 void Method::set_code(const methodHandle& mh, nmethod *code) {
1366   assert_lock_strong(NMethodState_lock);
1367   assert( code, "use clear_code to remove code" );
1368   assert( mh->check_code(), "" );
1369 
1370   guarantee(mh->adapter() != nullptr, "Adapter blob must already exist!");
1371 
1372   // These writes must happen in this order, because the interpreter will
1373   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1374   // which jumps to _from_compiled_entry.
1375   mh->_code = code;             // Assign before allowing compiled code to exec
1376 
1377   int comp_level = code->comp_level();
1378   // In theory there could be a race here. In practice it is unlikely
1379   // and not worth worrying about.
1380   if (comp_level > mh->highest_comp_level()) {
1381     mh->set_highest_comp_level(comp_level);
1382   }
1383 
1384   OrderAccess::storestore();
1385   mh->_from_compiled_entry = code->verified_entry_point();


1386   OrderAccess::storestore();
1387 
1388   if (mh->is_continuation_native_intrinsic()) {
1389     assert(mh->_from_interpreted_entry == nullptr, "initialized incorrectly"); // see link_method
1390 
1391     if (mh->is_continuation_enter_intrinsic()) {
1392       // This is the entry used when we're in interpreter-only mode; see InterpreterMacroAssembler::jump_from_interpreted
1393       mh->_i2i_entry = ContinuationEntry::interpreted_entry();
1394     } else if (mh->is_continuation_yield_intrinsic()) {
1395       mh->_i2i_entry = mh->get_i2c_entry();
1396     } else {
1397       guarantee(false, "Unknown Continuation native intrinsic");
1398     }
1399     // This must come last, as it is what's tested in LinkResolver::resolve_static_call
1400     AtomicAccess::release_store(&mh->_from_interpreted_entry , mh->get_i2c_entry());
1401   } else if (!mh->is_method_handle_intrinsic()) {
1402     // Instantly compiled code can execute.
1403     mh->_from_interpreted_entry = mh->get_i2c_entry();
1404   }
1405 }
1406 
1407 
1408 bool Method::is_overridden_in(Klass* k) const {
1409   InstanceKlass* ik = InstanceKlass::cast(k);
1410 
1411   if (ik->is_interface()) return false;
1412 
1413   // If method is an interface, we skip it - except if it
1414   // is a miranda method
1415   if (method_holder()->is_interface()) {
1416     // Check that method is not a miranda method
1417     if (ik->lookup_method(name(), signature()) == nullptr) {
1418       // No implementation exist - so miranda method
1419       return false;
1420     }
1421     return true;
1422   }
1423 
1424   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1425   if (!has_vtable_index()) {
1426     return false;
1427   } else {
1428     Method* vt_m = ik->method_at_vtable(vtable_index());
1429     return vt_m != this;
1430   }
1431 }
1432 
1433 
1434 // give advice about whether this Method* should be cached or not
1435 bool Method::should_not_be_cached() const {
1436   if (is_old()) {
1437     // This method has been redefined. It is either EMCP or obsolete
1438     // and we don't want to cache it because that would pin the method
1439     // down and prevent it from being collectible if and when it
1440     // finishes executing.
1441     return true;
1442   }
1443 
1444   // caching this method should be just fine
1445   return false;
1446 }
1447 
1448 
1449 /**
1450  *  Returns true if this is one of the specially treated methods for
1451  *  security related stack walks (like Reflection.getCallerClass).
1452  */
1453 bool Method::is_ignored_by_security_stack_walk() const {
1454   if (intrinsic_id() == vmIntrinsics::_invoke) {
1455     // This is Method.invoke() -- ignore it
1456     return true;
1457   }
1458   if (method_holder()->is_subclass_of(vmClasses::reflect_MethodAccessorImpl_klass())) {
1459     // This is an auxiliary frame -- ignore it
1460     return true;
1461   }
1462   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1463     // This is an internal adapter frame for method handles -- ignore it
1464     return true;
1465   }
1466   return false;
1467 }
1468 
1469 
1470 // Constant pool structure for invoke methods:
1471 enum {
1472   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1473   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1474   _imcp_limit
1475 };
1476 
1477 // Test if this method is an MH adapter frame generated by Java code.
1478 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1479 bool Method::is_compiled_lambda_form() const {
1480   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1481 }
1482 
1483 // Test if this method is an internal MH primitive method.
1484 bool Method::is_method_handle_intrinsic() const {
1485   vmIntrinsics::ID iid = intrinsic_id();
1486   return (MethodHandles::is_signature_polymorphic(iid) &&
1487           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1488 }
1489 
1490 bool Method::has_member_arg() const {
1491   vmIntrinsics::ID iid = intrinsic_id();
1492   return (MethodHandles::is_signature_polymorphic(iid) &&
1493           MethodHandles::has_member_arg(iid));
1494 }
1495 
1496 // Make an instance of a signature-polymorphic internal MH primitive.
1497 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1498                                                          Symbol* signature,
1499                                                          TRAPS) {
1500   ResourceMark rm(THREAD);
1501   methodHandle empty;
1502 
1503   InstanceKlass* holder = vmClasses::MethodHandle_klass();
1504   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1505   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1506 
1507   log_info(methodhandles)("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1508 
1509   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1510   name->increment_refcount();
1511   signature->increment_refcount();
1512 
1513   int cp_length = _imcp_limit;
1514   ClassLoaderData* loader_data = holder->class_loader_data();
1515   constantPoolHandle cp;
1516   {
1517     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1518     cp = constantPoolHandle(THREAD, cp_oop);
1519   }
1520   cp->copy_fields(holder->constants());
1521   cp->set_pool_holder(holder);
1522   cp->symbol_at_put(_imcp_invoke_name,       name);
1523   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1524   cp->set_has_preresolution();
1525   cp->set_is_for_method_handle_intrinsic();
1526 
1527   // decide on access bits:  public or not?
1528   u2 flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1529   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1530   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1531   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1532 
1533   methodHandle m;
1534   {
1535     InlineTableSizes sizes;
1536     Method* m_oop = Method::allocate(loader_data, 0,
1537                                      accessFlags_from(flags_bits), &sizes,
1538                                      ConstMethod::NORMAL,
1539                                      name,
1540                                      CHECK_(empty));
1541     m = methodHandle(THREAD, m_oop);
1542   }
1543   m->set_constants(cp());
1544   m->set_name_index(_imcp_invoke_name);
1545   m->set_signature_index(_imcp_invoke_signature);
1546   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1547   assert(m->signature() == signature, "");
1548   m->constMethod()->compute_from_signature(signature, must_be_static);
1549   m->init_intrinsic_id(klass_id_for_intrinsics(m->method_holder()));
1550   assert(m->is_method_handle_intrinsic(), "");
1551 #ifdef ASSERT
1552   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1553   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1554   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1555 #endif //ASSERT
1556 
1557   // Finally, set up its entry points.
1558   assert(m->can_be_statically_bound(), "");
1559   m->set_vtable_index(Method::nonvirtual_vtable_index);
1560   m->link_method(m, CHECK_(empty));
1561 
1562   if (iid == vmIntrinsics::_linkToNative) {
1563     m->set_interpreter_entry(m->adapter()->get_i2c_entry());
1564   }
1565   if (log_is_enabled(Debug, methodhandles)) {
1566     LogTarget(Debug, methodhandles) lt;
1567     LogStream ls(lt);
1568     m->print_on(&ls);
1569   }
1570 
1571   return m;
1572 }
1573 
1574 #if INCLUDE_CDS
1575 void Method::restore_archived_method_handle_intrinsic(methodHandle m, TRAPS) {
1576   if (m->adapter() != nullptr) {
1577     m->set_from_compiled_entry(m->adapter()->get_c2i_entry());


1578   }
1579   m->link_method(m, CHECK);
1580 
1581   if (m->intrinsic_id() == vmIntrinsics::_linkToNative) {
1582     m->set_interpreter_entry(m->adapter()->get_i2c_entry());
1583   }
1584 }
1585 #endif
1586 
1587 Klass* Method::check_non_bcp_klass(Klass* klass) {
1588   if (klass != nullptr && klass->class_loader() != nullptr) {
1589     if (klass->is_objArray_klass())
1590       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1591     return klass;
1592   }
1593   return nullptr;
1594 }
1595 
1596 
1597 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1598                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1599   // Code below does not work for native methods - they should never get rewritten anyway
1600   assert(!m->is_native(), "cannot rewrite native methods");
1601   // Allocate new Method*
1602   AccessFlags flags = m->access_flags();
1603 
1604   ConstMethod* cm = m->constMethod();
1605   int checked_exceptions_len = cm->checked_exceptions_length();
1606   int localvariable_len = cm->localvariable_table_length();
1607   int exception_table_len = cm->exception_table_length();
1608   int method_parameters_len = cm->method_parameters_length();
1609   int method_annotations_len = cm->method_annotations_length();
1610   int parameter_annotations_len = cm->parameter_annotations_length();
1611   int type_annotations_len = cm->type_annotations_length();
1612   int default_annotations_len = cm->default_annotations_length();
1613 
1614   InlineTableSizes sizes(
1615       localvariable_len,
1616       new_compressed_linenumber_size,
1617       exception_table_len,
1618       checked_exceptions_len,
1619       method_parameters_len,
1620       cm->generic_signature_index(),
1621       method_annotations_len,
1622       parameter_annotations_len,
1623       type_annotations_len,
1624       default_annotations_len,
1625       0);
1626 
1627   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1628   Method* newm_oop = Method::allocate(loader_data,
1629                                       new_code_length,
1630                                       flags,
1631                                       &sizes,
1632                                       m->method_type(),
1633                                       m->name(),
1634                                       CHECK_(methodHandle()));
1635   methodHandle newm (THREAD, newm_oop);
1636 
1637   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1638   ConstMethod* newcm = newm->constMethod();
1639   int new_const_method_size = newm->constMethod()->size();
1640 
1641   // This works because the source and target are both Methods. Some compilers
1642   // (e.g., clang) complain that the target vtable pointer will be stomped,
1643   // so cast away newm()'s and m()'s Methodness.
1644   memcpy((void*)newm(), (void*)m(), sizeof(Method));
1645 
1646   // Create shallow copy of ConstMethod.
1647   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1648 
1649   // Reset correct method/const method, method size, and parameter info
1650   newm->set_constMethod(newcm);
1651   newm->constMethod()->set_code_size(new_code_length);
1652   newm->constMethod()->set_constMethod_size(new_const_method_size);
1653   assert(newm->code_size() == new_code_length, "check");
1654   assert(newm->method_parameters_length() == method_parameters_len, "check");
1655   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1656   assert(newm->exception_table_length() == exception_table_len, "check");
1657   assert(newm->localvariable_table_length() == localvariable_len, "check");
1658   // Copy new byte codes
1659   memcpy(newm->code_base(), new_code, new_code_length);
1660   // Copy line number table
1661   if (new_compressed_linenumber_size > 0) {
1662     memcpy(newm->compressed_linenumber_table(),
1663            new_compressed_linenumber_table,
1664            new_compressed_linenumber_size);
1665   }
1666   // Copy method_parameters
1667   if (method_parameters_len > 0) {
1668     memcpy(newm->method_parameters_start(),
1669            m->method_parameters_start(),
1670            method_parameters_len * sizeof(MethodParametersElement));
1671   }
1672   // Copy checked_exceptions
1673   if (checked_exceptions_len > 0) {
1674     memcpy(newm->checked_exceptions_start(),
1675            m->checked_exceptions_start(),
1676            checked_exceptions_len * sizeof(CheckedExceptionElement));
1677   }
1678   // Copy exception table
1679   if (exception_table_len > 0) {
1680     memcpy(newm->exception_table_start(),
1681            m->exception_table_start(),
1682            exception_table_len * sizeof(ExceptionTableElement));
1683   }
1684   // Copy local variable number table
1685   if (localvariable_len > 0) {
1686     memcpy(newm->localvariable_table_start(),
1687            m->localvariable_table_start(),
1688            localvariable_len * sizeof(LocalVariableTableElement));
1689   }
1690   // Copy stackmap table
1691   if (m->has_stackmap_table()) {
1692     int code_attribute_length = m->stackmap_data()->length();
1693     Array<u1>* stackmap_data =
1694       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_(methodHandle()));
1695     memcpy((void*)stackmap_data->adr_at(0),
1696            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1697     newm->set_stackmap_data(stackmap_data);
1698   }
1699 
1700   // copy annotations over to new method
1701   newcm->copy_annotations_from(loader_data, cm, CHECK_(methodHandle()));
1702   return newm;
1703 }
1704 
1705 vmSymbolID Method::klass_id_for_intrinsics(const Klass* holder) {
1706   // if loader is not the default loader (i.e., non-null), we can't know the intrinsics
1707   // because we are not loading from core libraries
1708   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1709   // which does not use the class default class loader so we check for its loader here
1710   const InstanceKlass* ik = InstanceKlass::cast(holder);
1711   if ((ik->class_loader() != nullptr) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1712     return vmSymbolID::NO_SID;   // regardless of name, no intrinsics here
1713   }
1714 
1715   // see if the klass name is well-known:
1716   Symbol* klass_name = ik->name();
1717   vmSymbolID id = vmSymbols::find_sid(klass_name);
1718   if (id != vmSymbolID::NO_SID && vmIntrinsics::class_has_intrinsics(id)) {
1719     return id;
1720   } else {
1721     return vmSymbolID::NO_SID;
1722   }
1723 }
1724 
1725 void Method::init_intrinsic_id(vmSymbolID klass_id) {
1726   assert(_intrinsic_id == static_cast<int>(vmIntrinsics::_none), "do this just once");
1727   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1728   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1729   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1730 
1731   // the klass name is well-known:
1732   assert(klass_id == klass_id_for_intrinsics(method_holder()), "must be");
1733   assert(klass_id != vmSymbolID::NO_SID, "caller responsibility");
1734 
1735   // ditto for method and signature:
1736   vmSymbolID name_id = vmSymbols::find_sid(name());
1737   if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1738       && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1739       && name_id == vmSymbolID::NO_SID) {
1740     return;
1741   }
1742   vmSymbolID sig_id = vmSymbols::find_sid(signature());
1743   if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1744       && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1745       && sig_id == vmSymbolID::NO_SID) {
1746     return;
1747   }
1748 
1749   u2 flags = access_flags().as_method_flags();
1750   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1751   if (id != vmIntrinsics::_none) {
1752     set_intrinsic_id(id);
1753     if (id == vmIntrinsics::_Class_cast) {
1754       // Even if the intrinsic is rejected, we want to inline this simple method.
1755       set_force_inline();
1756     }
1757     return;
1758   }
1759 
1760   // A few slightly irregular cases:
1761   switch (klass_id) {
1762   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1763   case VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1764   case VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1765     if (!is_native())  break;
1766     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1767     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1768       id = vmIntrinsics::_none;
1769     break;
1770 
1771   default:
1772     break;
1773   }
1774 
1775   if (id != vmIntrinsics::_none) {
1776     // Set up its iid.  It is an alias method.
1777     set_intrinsic_id(id);
1778     return;
1779   }
1780 }
1781 
1782 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1783   if (!THREAD->can_call_java()) {
1784     // There is nothing useful this routine can do from within the Compile thread.
1785     // Hopefully, the signature contains only well-known classes.
1786     // We could scan for this and return true/false, but the caller won't care.
1787     return false;
1788   }
1789   bool sig_is_loaded = true;
1790   ResourceMark rm(THREAD);
1791   for (ResolvingSignatureStream ss(m()); !ss.is_done(); ss.next()) {
1792     if (ss.is_reference()) {
1793       // load everything, including arrays "[Lfoo;"
1794       Klass* klass = ss.as_klass(SignatureStream::ReturnNull, THREAD);
1795       // We are loading classes eagerly. If a ClassNotFoundException or
1796       // a LinkageError was generated, be sure to ignore it.
1797       if (HAS_PENDING_EXCEPTION) {
1798         if (PENDING_EXCEPTION->is_a(vmClasses::ClassNotFoundException_klass()) ||
1799             PENDING_EXCEPTION->is_a(vmClasses::LinkageError_klass())) {
1800           CLEAR_PENDING_EXCEPTION;
1801         } else {
1802           return false;
1803         }
1804       }
1805       if( klass == nullptr) { sig_is_loaded = false; }
1806     }
1807   }
1808   return sig_is_loaded;
1809 }
1810 
1811 // Exposed so field engineers can debug VM
1812 void Method::print_short_name(outputStream* st) const {
1813   ResourceMark rm;
1814 #ifdef PRODUCT
1815   st->print(" %s::", method_holder()->external_name());
1816 #else
1817   st->print(" %s::", method_holder()->internal_name());
1818 #endif
1819   name()->print_symbol_on(st);
1820   if (WizardMode) signature()->print_symbol_on(st);
1821   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1822     MethodHandles::print_as_basic_type_signature_on(st, signature());
1823 }
1824 
1825 // Comparer for sorting an object array containing
1826 // Method*s.
1827 static int method_comparator(Method* a, Method* b) {
1828   return a->name()->fast_compare(b->name());
1829 }
1830 
1831 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1832 // default_methods also uses this without the ordering for fast find_method
1833 void Method::sort_methods(Array<Method*>* methods, bool set_idnums, method_comparator_func func) {
1834   int length = methods->length();
1835   if (length > 1) {
1836     if (func == nullptr) {
1837       func = method_comparator;
1838     }
1839     {
1840       NoSafepointVerifier nsv;
1841       QuickSort::sort(methods->data(), length, func);
1842     }
1843     // Reset method ordering
1844     if (set_idnums) {
1845       for (u2 i = 0; i < length; i++) {
1846         Method* m = methods->at(i);
1847         m->set_method_idnum(i);
1848         m->set_orig_method_idnum(i);
1849       }
1850     }
1851   }
1852 }
1853 
1854 //-----------------------------------------------------------------------------------
1855 // Non-product code unless JVM/TI needs it
1856 
1857 #if !defined(PRODUCT) || INCLUDE_JVMTI
1858 class SignatureTypePrinter : public SignatureTypeNames {
1859  private:
1860   outputStream* _st;
1861   bool _use_separator;
1862 
1863   void type_name(const char* name) {
1864     if (_use_separator) _st->print(", ");
1865     _st->print("%s", name);
1866     _use_separator = true;
1867   }
1868 
1869  public:
1870   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1871     _st = st;
1872     _use_separator = false;
1873   }
1874 
1875   void print_parameters()              { _use_separator = false; do_parameters_on(this); }
1876   void print_returntype()              { _use_separator = false; do_type(return_type()); }
1877 };
1878 
1879 
1880 void Method::print_name(outputStream* st) const {
1881   Thread *thread = Thread::current();
1882   ResourceMark rm(thread);
1883   st->print("%s ", is_static() ? "static" : "virtual");
1884   if (WizardMode) {
1885     st->print("%s.", method_holder()->internal_name());
1886     name()->print_symbol_on(st);
1887     signature()->print_symbol_on(st);
1888   } else {
1889     SignatureTypePrinter sig(signature(), st);
1890     sig.print_returntype();
1891     st->print(" %s.", method_holder()->internal_name());
1892     name()->print_symbol_on(st);
1893     st->print("(");
1894     sig.print_parameters();
1895     st->print(")");
1896   }
1897 }
1898 #endif // !PRODUCT || INCLUDE_JVMTI
1899 
1900 
1901 void Method::print_codes_on(outputStream* st, int flags) const {
1902   print_codes_on(0, code_size(), st, flags);
1903 }
1904 
1905 void Method::print_codes_on(int from, int to, outputStream* st, int flags) const {
1906   Thread *thread = Thread::current();
1907   ResourceMark rm(thread);
1908   methodHandle mh (thread, (Method*)this);
1909   BytecodeTracer::print_method_codes(mh, from, to, st, flags);
1910 }
1911 
1912 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1913   _bci = 0;
1914   _line = 0;
1915 };
1916 
1917 bool CompressedLineNumberReadStream::read_pair() {
1918   jubyte next = read_byte();
1919   // Check for terminator
1920   if (next == 0) return false;
1921   if (next == 0xFF) {
1922     // Escape character, regular compression used
1923     _bci  += read_signed_int();
1924     _line += read_signed_int();
1925   } else {
1926     // Single byte compression used
1927     _bci  += next >> 3;
1928     _line += next & 0x7;
1929   }
1930   return true;
1931 }
1932 
1933 #if INCLUDE_JVMTI
1934 
1935 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1936   BreakpointInfo* bp = method_holder()->breakpoints();
1937   for (; bp != nullptr; bp = bp->next()) {
1938     if (bp->match(this, bci)) {
1939       return bp->orig_bytecode();
1940     }
1941   }
1942   {
1943     ResourceMark rm;
1944     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1945   }
1946   return Bytecodes::_shouldnotreachhere;
1947 }
1948 
1949 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1950   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1951   BreakpointInfo* bp = method_holder()->breakpoints();
1952   for (; bp != nullptr; bp = bp->next()) {
1953     if (bp->match(this, bci)) {
1954       bp->set_orig_bytecode(code);
1955       // and continue, in case there is more than one
1956     }
1957   }
1958 }
1959 
1960 void Method::set_breakpoint(int bci) {
1961   InstanceKlass* ik = method_holder();
1962   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1963   bp->set_next(ik->breakpoints());
1964   ik->set_breakpoints(bp);
1965   // do this last:
1966   bp->set(this);
1967 }
1968 
1969 static void clear_matches(Method* m, int bci) {
1970   InstanceKlass* ik = m->method_holder();
1971   BreakpointInfo* prev_bp = nullptr;
1972   BreakpointInfo* next_bp;
1973   for (BreakpointInfo* bp = ik->breakpoints(); bp != nullptr; bp = next_bp) {
1974     next_bp = bp->next();
1975     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1976     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1977       // do this first:
1978       bp->clear(m);
1979       // unhook it
1980       if (prev_bp != nullptr)
1981         prev_bp->set_next(next_bp);
1982       else
1983         ik->set_breakpoints(next_bp);
1984       delete bp;
1985       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1986       // at same location. So we have multiple matching (method_index and bci)
1987       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1988       // breakpoint for clear_breakpoint request and keep all other method versions
1989       // BreakpointInfo for future clear_breakpoint request.
1990       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1991       // which is being called when class is unloaded. We delete all the Breakpoint
1992       // information for all versions of method. We may not correctly restore the original
1993       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1994       // so these methods won't be used anymore.
1995       if (bci >= 0) {
1996         break;
1997       }
1998     } else {
1999       // This one is a keeper.
2000       prev_bp = bp;
2001     }
2002   }
2003 }
2004 
2005 void Method::clear_breakpoint(int bci) {
2006   assert(bci >= 0, "");
2007   clear_matches(this, bci);
2008 }
2009 
2010 void Method::clear_all_breakpoints() {
2011   clear_matches(this, -1);
2012 }
2013 
2014 #endif // INCLUDE_JVMTI
2015 
2016 int Method::highest_osr_comp_level() const {
2017   const MethodCounters* mcs = method_counters();
2018   if (mcs != nullptr) {
2019     return mcs->highest_osr_comp_level();
2020   } else {
2021     return CompLevel_none;
2022   }
2023 }
2024 
2025 void Method::set_highest_comp_level(int level) {
2026   MethodCounters* mcs = method_counters();
2027   if (mcs != nullptr) {
2028     mcs->set_highest_comp_level(level);
2029   }
2030 }
2031 
2032 void Method::set_highest_osr_comp_level(int level) {
2033   MethodCounters* mcs = method_counters();
2034   if (mcs != nullptr) {
2035     mcs->set_highest_osr_comp_level(level);
2036   }
2037 }
2038 
2039 #if INCLUDE_JVMTI
2040 
2041 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
2042   _bci = bci;
2043   _name_index = m->name_index();
2044   _signature_index = m->signature_index();
2045   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
2046   if (_orig_bytecode == Bytecodes::_breakpoint)
2047     _orig_bytecode = m->orig_bytecode_at(_bci);
2048   _next = nullptr;
2049 }
2050 
2051 void BreakpointInfo::set(Method* method) {
2052 #ifdef ASSERT
2053   {
2054     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
2055     if (code == Bytecodes::_breakpoint)
2056       code = method->orig_bytecode_at(_bci);
2057     assert(orig_bytecode() == code, "original bytecode must be the same");
2058   }
2059 #endif
2060   Thread *thread = Thread::current();
2061   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2062   method->incr_number_of_breakpoints(thread);
2063   {
2064     // Deoptimize all dependents on this method
2065     HandleMark hm(thread);
2066     methodHandle mh(thread, method);
2067     CodeCache::mark_dependents_on_method_for_breakpoint(mh);
2068   }
2069 }
2070 
2071 void BreakpointInfo::clear(Method* method) {
2072   *method->bcp_from(_bci) = orig_bytecode();
2073   assert(method->number_of_breakpoints() > 0, "must not go negative");
2074   method->decr_number_of_breakpoints(Thread::current());
2075 }
2076 
2077 #endif // INCLUDE_JVMTI
2078 
2079 // jmethodID handling
2080 // jmethodIDs are 64-bit integers that will never run out and are mapped in a table
2081 // to their Method and vice versa.  If JNI code has access to stale jmethodID, this
2082 // wastes no memory but the Method* returned is null.
2083 
2084 // Add a method id to the jmethod_ids
2085 jmethodID Method::make_jmethod_id(ClassLoaderData* cld, Method* m) {
2086   // Have to add jmethod_ids() to class loader data thread-safely.
2087   // Also have to add the method to the InstanceKlass list safely, which the lock
2088   // protects as well.
2089   assert(JmethodIdCreation_lock->owned_by_self(), "sanity check");
2090   jmethodID jmid = JmethodIDTable::make_jmethod_id(m);
2091   assert(jmid != nullptr, "must be created");
2092 
2093   // Add to growable array in CLD.
2094   cld->add_jmethod_id(jmid);
2095   return jmid;
2096 }
2097 
2098 // This looks in the InstanceKlass cache, then calls back to make_jmethod_id if not found.
2099 jmethodID Method::jmethod_id() {
2100   return method_holder()->get_jmethod_id(this);
2101 }
2102 
2103 // Get the Method out of the table given the method id.
2104 Method* Method::resolve_jmethod_id(jmethodID mid) {
2105   assert(mid != nullptr, "JNI method id should not be null");
2106   return JmethodIDTable::resolve_jmethod_id(mid);
2107 }
2108 
2109 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2110   // Can't assert the method_holder is the same because the new method has the
2111   // scratch method holder.
2112   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2113            == new_method->method_holder()->class_loader() ||
2114          new_method->method_holder()->class_loader() == nullptr, // allow substitution to Unsafe method
2115          "changing to a different class loader");
2116   JmethodIDTable::change_method_associated_with_jmethod_id(jmid, new_method);
2117 }
2118 
2119 // If there's a jmethodID for this method, clear the Method
2120 // but leave jmethodID for this method in the table.
2121 // It's deallocated with class unloading.
2122 void Method::clear_jmethod_id() {
2123   jmethodID mid = method_holder()->jmethod_id_or_null(this);
2124   if (mid != nullptr) {
2125     JmethodIDTable::clear_jmethod_id(mid, this);
2126   }
2127 }
2128 
2129 bool Method::validate_jmethod_id(jmethodID mid) {
2130   Method* m = resolve_jmethod_id(mid);
2131   assert(m != nullptr, "should be called with non-null method");
2132   InstanceKlass* ik = m->method_holder();
2133   ClassLoaderData* cld = ik->class_loader_data();
2134   if (cld->jmethod_ids() == nullptr) return false;
2135   return (cld->jmethod_ids()->contains(mid));
2136 }
2137 
2138 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2139   if (mid == nullptr) return nullptr;
2140   Method* o = resolve_jmethod_id(mid);
2141   if (o == nullptr) {
2142     return nullptr;
2143   }
2144   // Method should otherwise be valid. Assert for testing.
2145   assert(is_valid_method(o), "should be valid jmethodid");
2146   // If the method's class holder object is unreferenced, but not yet marked as
2147   // unloaded, we need to return null here too because after a safepoint, its memory
2148   // will be reclaimed.
2149   return o->method_holder()->is_loader_alive() ? o : nullptr;
2150 }
2151 
2152 void Method::set_on_stack(const bool value) {
2153   // Set both the method itself and its constant pool.  The constant pool
2154   // on stack means some method referring to it is also on the stack.
2155   constants()->set_on_stack(value);
2156 
2157   bool already_set = on_stack_flag();
2158   set_on_stack_flag(value);
2159   if (value && !already_set) {
2160     MetadataOnStackMark::record(this);
2161   }
2162 }
2163 
2164 void Method::record_gc_epoch() {
2165   // If any method is on the stack in continuations, none of them can be reclaimed,
2166   // so save the marking cycle to check for the whole class in the cpCache.
2167   // The cpCache is writeable.
2168   constants()->cache()->record_gc_epoch();
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 Method* m) {
2179   if (m == nullptr) {
2180     return false;
2181   } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2182     // Quick sanity check on pointer.
2183     return false;
2184   } else if (!os::is_readable_range(m, m + 1)) {
2185     return false;
2186   } else if (m->in_aot_cache()) {
2187     return CppVtables::is_valid_shared_method(m);
2188   } else if (Metaspace::contains_non_shared(m)) {
2189     return has_method_vptr((const void*)m);
2190   } else {
2191     return false;
2192   }
2193 }
2194 

























2195 // Printing
2196 
2197 #ifndef PRODUCT
2198 
2199 void Method::print_on(outputStream* st) const {
2200   ResourceMark rm;
2201   assert(is_method(), "must be method");
2202   st->print_cr("%s", internal_name());
2203   st->print_cr(" - this oop:          " PTR_FORMAT, p2i(this));
2204   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2205   st->print   (" - constants:         " PTR_FORMAT " ", p2i(constants()));
2206   constants()->print_value_on(st); st->cr();
2207   st->print   (" - access:            0x%x  ", access_flags().as_method_flags()); access_flags().print_on(st); st->cr();
2208   st->print   (" - flags:             0x%x  ", _flags.as_int()); _flags.print_on(st); st->cr();
2209   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2210   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2211   st->print_cr(" - max stack:         %d",   max_stack());
2212   st->print_cr(" - max locals:        %d",   max_locals());
2213   st->print_cr(" - size of params:    %d",   size_of_parameters());
2214   st->print_cr(" - method size:       %d",   method_size());
2215   if (intrinsic_id() != vmIntrinsics::_none)
2216     st->print_cr(" - intrinsic id:      %d %s", vmIntrinsics::as_int(intrinsic_id()), vmIntrinsics::name_at(intrinsic_id()));
2217   if (highest_comp_level() != CompLevel_none)
2218     st->print_cr(" - highest level:     %d", highest_comp_level());
2219   st->print_cr(" - vtable index:      %d",   _vtable_index);




2220   st->print_cr(" - i2i entry:         " PTR_FORMAT, p2i(interpreter_entry()));
2221   st->print(   " - adapters:          ");
2222   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2223   if (a == nullptr)
2224     st->print_cr(PTR_FORMAT, p2i(a));
2225   else
2226     a->print_adapter_on(st);
2227   st->print_cr(" - compiled entry     " PTR_FORMAT, p2i(from_compiled_entry()));


2228   st->print_cr(" - code size:         %d",   code_size());
2229   if (code_size() != 0) {
2230     st->print_cr(" - code start:        " PTR_FORMAT, p2i(code_base()));
2231     st->print_cr(" - code end (excl):   " PTR_FORMAT, p2i(code_base() + code_size()));
2232   }
2233   if (method_data() != nullptr) {
2234     st->print_cr(" - method data:       " PTR_FORMAT, p2i(method_data()));
2235   }
2236   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2237   if (checked_exceptions_length() > 0) {
2238     CheckedExceptionElement* table = checked_exceptions_start();
2239     st->print_cr(" - checked ex start:  " PTR_FORMAT, p2i(table));
2240     if (Verbose) {
2241       for (int i = 0; i < checked_exceptions_length(); i++) {
2242         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2243       }
2244     }
2245   }
2246   if (has_linenumber_table()) {
2247     u_char* table = compressed_linenumber_table();
2248     st->print_cr(" - linenumber start:  " PTR_FORMAT, p2i(table));
2249     if (Verbose) {
2250       CompressedLineNumberReadStream stream(table);
2251       while (stream.read_pair()) {
2252         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2253       }
2254     }
2255   }
2256   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2257   if (localvariable_table_length() > 0) {
2258     LocalVariableTableElement* table = localvariable_table_start();
2259     st->print_cr(" - localvar start:    " PTR_FORMAT, p2i(table));
2260     if (Verbose) {
2261       for (int i = 0; i < localvariable_table_length(); i++) {
2262         int bci = table[i].start_bci;
2263         int len = table[i].length;
2264         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2265         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2266         int slot = table[i].slot;
2267         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2268       }
2269     }
2270   }
2271   if (code() != nullptr) {
2272     st->print   (" - compiled code: ");
2273     code()->print_value_on(st);
2274   }
2275   if (is_native()) {
2276     st->print_cr(" - native function:   " PTR_FORMAT, p2i(native_function()));
2277     st->print_cr(" - signature handler: " PTR_FORMAT, p2i(signature_handler()));
2278   }
2279 }
2280 
2281 void Method::print_linkage_flags(outputStream* st) {
2282   access_flags().print_on(st);
2283   if (is_default_method()) {
2284     st->print("default ");
2285   }
2286   if (is_overpass()) {
2287     st->print("overpass ");
2288   }
2289 }
2290 #endif //PRODUCT
2291 
2292 void Method::print_value_on(outputStream* st) const {
2293   assert(is_method(), "must be method");
2294   st->print("%s", internal_name());
2295   print_address_on(st);
2296   st->print(" ");

2297   name()->print_value_on(st);
2298   st->print(" ");
2299   signature()->print_value_on(st);
2300   st->print(" in ");
2301   method_holder()->print_value_on(st);
2302   if (WizardMode) st->print("#%d", _vtable_index);
2303   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2304   if (WizardMode && code() != nullptr) st->print(" ((nmethod*)%p)", code());
2305 }
2306 
2307 // Verification
2308 
2309 void Method::verify_on(outputStream* st) {
2310   guarantee(is_method(), "object must be method");
2311   guarantee(constants()->is_constantPool(), "should be constant pool");
2312   MethodData* md = method_data();
2313   guarantee(md == nullptr ||
2314       md->is_methodData(), "should be method data");
2315 }
--- EOF ---