1 /*
   2  * Copyright (c) 1997, 2026, 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 "asm/assembler.inline.hpp"
  26 #include "cds/cdsConfig.hpp"
  27 #include "code/aotCodeCache.hpp"
  28 #include "code/codeCache.hpp"
  29 #include "code/compiledIC.hpp"
  30 #include "code/dependencies.hpp"
  31 #include "code/nativeInst.hpp"
  32 #include "code/nmethod.inline.hpp"
  33 #include "code/scopeDesc.hpp"
  34 #include "compiler/abstractCompiler.hpp"
  35 #include "compiler/compilationLog.hpp"
  36 #include "compiler/compileBroker.hpp"
  37 #include "compiler/compileLog.hpp"
  38 #include "compiler/compilerDirectives.hpp"
  39 #include "compiler/compilerOracle.hpp"
  40 #include "compiler/compileTask.hpp"
  41 #include "compiler/directivesParser.hpp"
  42 #include "compiler/disassembler.hpp"
  43 #include "compiler/oopMap.inline.hpp"
  44 #include "gc/shared/barrierSet.hpp"
  45 #include "gc/shared/barrierSetNMethod.hpp"
  46 #include "gc/shared/classUnloadingContext.hpp"
  47 #include "gc/shared/collectedHeap.hpp"
  48 #include "interpreter/bytecode.inline.hpp"
  49 #include "jvm.h"
  50 #include "logging/log.hpp"
  51 #include "logging/logStream.hpp"
  52 #include "memory/allocation.inline.hpp"
  53 #include "memory/resourceArea.hpp"
  54 #include "memory/universe.hpp"
  55 #include "oops/access.inline.hpp"
  56 #include "oops/klass.inline.hpp"
  57 #include "oops/method.inline.hpp"
  58 #include "oops/methodData.hpp"
  59 #include "oops/oop.inline.hpp"
  60 #include "oops/trainingData.hpp"
  61 #include "oops/weakHandle.inline.hpp"
  62 #include "prims/jvmtiImpl.hpp"
  63 #include "prims/jvmtiThreadState.hpp"
  64 #include "prims/methodHandles.hpp"
  65 #include "runtime/atomicAccess.hpp"
  66 #include "runtime/continuation.hpp"
  67 #include "runtime/deoptimization.hpp"
  68 #include "runtime/flags/flagSetting.hpp"
  69 #include "runtime/frame.inline.hpp"
  70 #include "runtime/handles.inline.hpp"
  71 #include "runtime/jniHandles.inline.hpp"
  72 #include "runtime/orderAccess.hpp"
  73 #include "runtime/os.hpp"
  74 #include "runtime/safepointVerifiers.hpp"
  75 #include "runtime/serviceThread.hpp"
  76 #include "runtime/sharedRuntime.hpp"
  77 #include "runtime/signature.hpp"
  78 #include "runtime/threadWXSetters.inline.hpp"
  79 #include "runtime/vmThread.hpp"
  80 #include "utilities/align.hpp"
  81 #include "utilities/copy.hpp"
  82 #include "utilities/dtrace.hpp"
  83 #include "utilities/events.hpp"
  84 #include "utilities/globalDefinitions.hpp"
  85 #include "utilities/hashTable.hpp"
  86 #include "utilities/xmlstream.hpp"
  87 #if INCLUDE_JVMCI
  88 #include "jvmci/jvmciRuntime.hpp"
  89 #endif
  90 
  91 #ifdef DTRACE_ENABLED
  92 
  93 // Only bother with this argument setup if dtrace is available
  94 
  95 #define DTRACE_METHOD_UNLOAD_PROBE(method)                                \
  96   {                                                                       \
  97     Method* m = (method);                                                 \
  98     if (m != nullptr) {                                                   \
  99       Symbol* klass_name = m->klass_name();                               \
 100       Symbol* name = m->name();                                           \
 101       Symbol* signature = m->signature();                                 \
 102       HOTSPOT_COMPILED_METHOD_UNLOAD(                                     \
 103         (char *) klass_name->bytes(), klass_name->utf8_length(),          \
 104         (char *) name->bytes(), name->utf8_length(),                      \
 105         (char *) signature->bytes(), signature->utf8_length());           \
 106     }                                                                     \
 107   }
 108 
 109 #else //  ndef DTRACE_ENABLED
 110 
 111 #define DTRACE_METHOD_UNLOAD_PROBE(method)
 112 
 113 #endif
 114 
 115 // Cast from int value to narrow type
 116 #define CHECKED_CAST(result, T, thing)      \
 117   result = static_cast<T>(thing); \
 118   guarantee(static_cast<int>(result) == thing, "failed: %d != %d", static_cast<int>(result), thing);
 119 
 120 //---------------------------------------------------------------------------------
 121 // NMethod statistics
 122 // They are printed under various flags, including:
 123 //   PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
 124 // (In the latter two cases, they like other stats are printed to the log only.)
 125 
 126 #ifndef PRODUCT
 127 // These variables are put into one block to reduce relocations
 128 // and make it simpler to print from the debugger.
 129 struct java_nmethod_stats_struct {
 130   uint nmethod_count;
 131   uint total_nm_size;
 132   uint total_immut_size;
 133   uint total_mut_size;
 134   uint relocation_size;
 135   uint consts_size;
 136   uint insts_size;
 137   uint stub_size;
 138   uint oops_size;
 139   uint metadata_size;
 140   uint dependencies_size;
 141   uint nul_chk_table_size;
 142   uint handler_table_size;
 143   uint scopes_pcs_size;
 144   uint scopes_data_size;
 145 #if INCLUDE_JVMCI
 146   uint speculations_size;
 147   uint jvmci_data_size;
 148 #endif
 149 
 150   void note_nmethod(nmethod* nm) {
 151     nmethod_count += 1;
 152     total_nm_size       += nm->size();
 153     total_immut_size    += nm->immutable_data_size();
 154     total_mut_size      += nm->mutable_data_size();
 155     relocation_size     += nm->relocation_size();
 156     consts_size         += nm->consts_size();
 157     insts_size          += nm->insts_size();
 158     stub_size           += nm->stub_size();
 159     oops_size           += nm->oops_size();
 160     metadata_size       += nm->metadata_size();
 161     scopes_data_size    += nm->scopes_data_size();
 162     scopes_pcs_size     += nm->scopes_pcs_size();
 163     dependencies_size   += nm->dependencies_size();
 164     handler_table_size  += nm->handler_table_size();
 165     nul_chk_table_size  += nm->nul_chk_table_size();
 166 #if INCLUDE_JVMCI
 167     speculations_size   += nm->speculations_size();
 168     jvmci_data_size     += nm->jvmci_data_size();
 169 #endif
 170   }
 171   void print_nmethod_stats(const char* name) {
 172     if (nmethod_count == 0)  return;
 173     tty->print_cr("Statistics for %u bytecoded nmethods for %s:", nmethod_count, name);
 174     uint total_size = total_nm_size + total_immut_size + total_mut_size;
 175     if (total_nm_size != 0) {
 176       tty->print_cr(" total size      = %u (100%%)", total_size);
 177       tty->print_cr(" in CodeCache    = %u (%f%%)", total_nm_size, (total_nm_size * 100.0f)/total_size);
 178     }
 179     uint header_size = (uint)(nmethod_count * sizeof(nmethod));
 180     if (nmethod_count != 0) {
 181       tty->print_cr("   header        = %u (%f%%)", header_size, (header_size * 100.0f)/total_nm_size);
 182     }
 183     if (consts_size != 0) {
 184       tty->print_cr("   constants     = %u (%f%%)", consts_size, (consts_size * 100.0f)/total_nm_size);
 185     }
 186     if (insts_size != 0) {
 187       tty->print_cr("   main code     = %u (%f%%)", insts_size, (insts_size * 100.0f)/total_nm_size);
 188     }
 189     if (stub_size != 0) {
 190       tty->print_cr("   stub code     = %u (%f%%)", stub_size, (stub_size * 100.0f)/total_nm_size);
 191     }
 192     if (oops_size != 0) {
 193       tty->print_cr("   oops          = %u (%f%%)", oops_size, (oops_size * 100.0f)/total_nm_size);
 194     }
 195     if (total_mut_size != 0) {
 196       tty->print_cr(" mutable data    = %u (%f%%)", total_mut_size, (total_mut_size * 100.0f)/total_size);
 197     }
 198     if (relocation_size != 0) {
 199       tty->print_cr("   relocation    = %u (%f%%)", relocation_size, (relocation_size * 100.0f)/total_mut_size);
 200     }
 201     if (metadata_size != 0) {
 202       tty->print_cr("   metadata      = %u (%f%%)", metadata_size, (metadata_size * 100.0f)/total_mut_size);
 203     }
 204 #if INCLUDE_JVMCI
 205     if (jvmci_data_size != 0) {
 206       tty->print_cr("   JVMCI data    = %u (%f%%)", jvmci_data_size, (jvmci_data_size * 100.0f)/total_mut_size);
 207     }
 208 #endif
 209     if (total_immut_size != 0) {
 210       tty->print_cr(" immutable data  = %u (%f%%)", total_immut_size, (total_immut_size * 100.0f)/total_size);
 211     }
 212     if (dependencies_size != 0) {
 213       tty->print_cr("   dependencies  = %u (%f%%)", dependencies_size, (dependencies_size * 100.0f)/total_immut_size);
 214     }
 215     if (nul_chk_table_size != 0) {
 216       tty->print_cr("   nul chk table = %u (%f%%)", nul_chk_table_size, (nul_chk_table_size * 100.0f)/total_immut_size);
 217     }
 218     if (handler_table_size != 0) {
 219       tty->print_cr("   handler table = %u (%f%%)", handler_table_size, (handler_table_size * 100.0f)/total_immut_size);
 220     }
 221     if (scopes_pcs_size != 0) {
 222       tty->print_cr("   scopes pcs    = %u (%f%%)", scopes_pcs_size, (scopes_pcs_size * 100.0f)/total_immut_size);
 223     }
 224     if (scopes_data_size != 0) {
 225       tty->print_cr("   scopes data   = %u (%f%%)", scopes_data_size, (scopes_data_size * 100.0f)/total_immut_size);
 226     }
 227 #if INCLUDE_JVMCI
 228     if (speculations_size != 0) {
 229       tty->print_cr("   speculations  = %u (%f%%)", speculations_size, (speculations_size * 100.0f)/total_immut_size);
 230     }
 231 #endif
 232   }
 233 };
 234 
 235 struct native_nmethod_stats_struct {
 236   uint native_nmethod_count;
 237   uint native_total_size;
 238   uint native_relocation_size;
 239   uint native_insts_size;
 240   uint native_oops_size;
 241   uint native_metadata_size;
 242   void note_native_nmethod(nmethod* nm) {
 243     native_nmethod_count += 1;
 244     native_total_size       += nm->size();
 245     native_relocation_size  += nm->relocation_size();
 246     native_insts_size       += nm->insts_size();
 247     native_oops_size        += nm->oops_size();
 248     native_metadata_size    += nm->metadata_size();
 249   }
 250   void print_native_nmethod_stats() {
 251     if (native_nmethod_count == 0)  return;
 252     tty->print_cr("Statistics for %u native nmethods:", native_nmethod_count);
 253     if (native_total_size != 0)       tty->print_cr(" N. total size  = %u", native_total_size);
 254     if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %u", native_relocation_size);
 255     if (native_insts_size != 0)       tty->print_cr(" N. main code   = %u", native_insts_size);
 256     if (native_oops_size != 0)        tty->print_cr(" N. oops        = %u", native_oops_size);
 257     if (native_metadata_size != 0)    tty->print_cr(" N. metadata    = %u", native_metadata_size);
 258   }
 259 };
 260 
 261 struct pc_nmethod_stats_struct {
 262   uint pc_desc_init;     // number of initialization of cache (= number of caches)
 263   uint pc_desc_queries;  // queries to nmethod::find_pc_desc
 264   uint pc_desc_approx;   // number of those which have approximate true
 265   uint pc_desc_repeats;  // number of _pc_descs[0] hits
 266   uint pc_desc_hits;     // number of LRU cache hits
 267   uint pc_desc_tests;    // total number of PcDesc examinations
 268   uint pc_desc_searches; // total number of quasi-binary search steps
 269   uint pc_desc_adds;     // number of LUR cache insertions
 270 
 271   void print_pc_stats() {
 272     tty->print_cr("PcDesc Statistics:  %u queries, %.2f comparisons per query",
 273                   pc_desc_queries,
 274                   (double)(pc_desc_tests + pc_desc_searches)
 275                   / pc_desc_queries);
 276     tty->print_cr("  caches=%d queries=%u/%u, hits=%u+%u, tests=%u+%u, adds=%u",
 277                   pc_desc_init,
 278                   pc_desc_queries, pc_desc_approx,
 279                   pc_desc_repeats, pc_desc_hits,
 280                   pc_desc_tests, pc_desc_searches, pc_desc_adds);
 281   }
 282 };
 283 
 284 #ifdef COMPILER1
 285 static java_nmethod_stats_struct c1_java_nmethod_stats;
 286 #endif
 287 #ifdef COMPILER2
 288 static java_nmethod_stats_struct c2_java_nmethod_stats;
 289 #endif
 290 #if INCLUDE_JVMCI
 291 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
 292 #endif
 293 static java_nmethod_stats_struct unknown_java_nmethod_stats;
 294 
 295 static native_nmethod_stats_struct native_nmethod_stats;
 296 static pc_nmethod_stats_struct pc_nmethod_stats;
 297 
 298 static void note_java_nmethod(nmethod* nm) {
 299 #ifdef COMPILER1
 300   if (nm->is_compiled_by_c1()) {
 301     c1_java_nmethod_stats.note_nmethod(nm);
 302   } else
 303 #endif
 304 #ifdef COMPILER2
 305   if (nm->is_compiled_by_c2()) {
 306     c2_java_nmethod_stats.note_nmethod(nm);
 307   } else
 308 #endif
 309 #if INCLUDE_JVMCI
 310   if (nm->is_compiled_by_jvmci()) {
 311     jvmci_java_nmethod_stats.note_nmethod(nm);
 312   } else
 313 #endif
 314   {
 315     unknown_java_nmethod_stats.note_nmethod(nm);
 316   }
 317 }
 318 #endif // !PRODUCT
 319 
 320 //---------------------------------------------------------------------------------
 321 
 322 
 323 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
 324   assert(pc != nullptr, "Must be non null");
 325   assert(exception.not_null(), "Must be non null");
 326   assert(handler != nullptr, "Must be non null");
 327 
 328   _count = 0;
 329   _exception_type = exception->klass();
 330   _next = nullptr;
 331   _purge_list_next = nullptr;
 332 
 333   add_address_and_handler(pc,handler);
 334 }
 335 
 336 
 337 address ExceptionCache::match(Handle exception, address pc) {
 338   assert(pc != nullptr,"Must be non null");
 339   assert(exception.not_null(),"Must be non null");
 340   if (exception->klass() == exception_type()) {
 341     return (test_address(pc));
 342   }
 343 
 344   return nullptr;
 345 }
 346 
 347 
 348 bool ExceptionCache::match_exception_with_space(Handle exception) {
 349   assert(exception.not_null(),"Must be non null");
 350   if (exception->klass() == exception_type() && count() < cache_size) {
 351     return true;
 352   }
 353   return false;
 354 }
 355 
 356 
 357 address ExceptionCache::test_address(address addr) {
 358   int limit = count();
 359   for (int i = 0; i < limit; i++) {
 360     if (pc_at(i) == addr) {
 361       return handler_at(i);
 362     }
 363   }
 364   return nullptr;
 365 }
 366 
 367 
 368 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
 369   if (test_address(addr) == handler) return true;
 370 
 371   int index = count();
 372   if (index < cache_size) {
 373     set_pc_at(index, addr);
 374     set_handler_at(index, handler);
 375     increment_count();
 376     return true;
 377   }
 378   return false;
 379 }
 380 
 381 ExceptionCache* ExceptionCache::next() {
 382   return AtomicAccess::load(&_next);
 383 }
 384 
 385 void ExceptionCache::set_next(ExceptionCache *ec) {
 386   AtomicAccess::store(&_next, ec);
 387 }
 388 
 389 //-----------------------------------------------------------------------------
 390 
 391 
 392 // Helper used by both find_pc_desc methods.
 393 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
 394   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
 395   if (!approximate) {
 396     return pc->pc_offset() == pc_offset;
 397   } else {
 398     // Do not look before the sentinel
 399     assert(pc_offset > PcDesc::lower_offset_limit, "illegal pc_offset");
 400     return pc_offset <= pc->pc_offset() && (pc-1)->pc_offset() < pc_offset;
 401   }
 402 }
 403 
 404 void PcDescCache::init_to(PcDesc* initial_pc_desc) {
 405   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_init);
 406   // initialize the cache by filling it with benign (non-null) values
 407   assert(initial_pc_desc != nullptr && initial_pc_desc->pc_offset() == PcDesc::lower_offset_limit,
 408          "must start with a sentinel");
 409   for (int i = 0; i < cache_size; i++) {
 410     _pc_descs[i] = initial_pc_desc;
 411   }
 412 }
 413 
 414 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
 415   // Note: one might think that caching the most recently
 416   // read value separately would be a win, but one would be
 417   // wrong.  When many threads are updating it, the cache
 418   // line it's in would bounce between caches, negating
 419   // any benefit.
 420 
 421   // In order to prevent race conditions do not load cache elements
 422   // repeatedly, but use a local copy:
 423   PcDesc* res;
 424 
 425   // Step one:  Check the most recently added value.
 426   res = _pc_descs[0];
 427   assert(res != nullptr, "PcDesc cache should be initialized already");
 428 
 429   // Approximate only here since PcDescContainer::find_pc_desc() checked for exact case.
 430   if (approximate && match_desc(res, pc_offset, approximate)) {
 431     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
 432     return res;
 433   }
 434 
 435   // Step two:  Check the rest of the LRU cache.
 436   for (int i = 1; i < cache_size; ++i) {
 437     res = _pc_descs[i];
 438     if (res->pc_offset() < 0) break;  // optimization: skip empty cache
 439     if (match_desc(res, pc_offset, approximate)) {
 440       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
 441       return res;
 442     }
 443   }
 444 
 445   // Report failure.
 446   return nullptr;
 447 }
 448 
 449 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
 450   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
 451   // Update the LRU cache by shifting pc_desc forward.
 452   for (int i = 0; i < cache_size; i++)  {
 453     PcDesc* next = _pc_descs[i];
 454     _pc_descs[i] = pc_desc;
 455     pc_desc = next;
 456   }
 457 }
 458 
 459 // adjust pcs_size so that it is a multiple of both oopSize and
 460 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
 461 // of oopSize, then 2*sizeof(PcDesc) is)
 462 static int adjust_pcs_size(int pcs_size) {
 463   int nsize = align_up(pcs_size,   oopSize);
 464   if ((nsize % sizeof(PcDesc)) != 0) {
 465     nsize = pcs_size + sizeof(PcDesc);
 466   }
 467   assert((nsize % oopSize) == 0, "correct alignment");
 468   return nsize;
 469 }
 470 
 471 // Returns a string version of the method state.
 472 const char* nmethod::state() const {
 473   int state = get_state();
 474   switch (state) {
 475   case not_installed:
 476     return "not installed";
 477   case in_use:
 478     return "in use";
 479   case not_entrant:
 480     return "not_entrant";
 481   default:
 482     fatal("unexpected method state: %d", state);
 483     return nullptr;
 484   }
 485 }
 486 
 487 void nmethod::set_deoptimized_done() {
 488   ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
 489   if (_deoptimization_status != deoptimize_done) { // can't go backwards
 490     AtomicAccess::store(&_deoptimization_status, deoptimize_done);
 491   }
 492 }
 493 
 494 ExceptionCache* nmethod::exception_cache_acquire() const {
 495   return AtomicAccess::load_acquire(&_exception_cache);
 496 }
 497 
 498 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
 499   assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
 500   assert(new_entry != nullptr,"Must be non null");
 501   assert(new_entry->next() == nullptr, "Must be null");
 502 
 503   for (;;) {
 504     ExceptionCache *ec = exception_cache();
 505     if (ec != nullptr) {
 506       Klass* ex_klass = ec->exception_type();
 507       if (!ex_klass->is_loader_alive()) {
 508         // We must guarantee that entries are not inserted with new next pointer
 509         // edges to ExceptionCache entries with dead klasses, due to bad interactions
 510         // with concurrent ExceptionCache cleanup. Therefore, the inserts roll
 511         // the head pointer forward to the first live ExceptionCache, so that the new
 512         // next pointers always point at live ExceptionCaches, that are not removed due
 513         // to concurrent ExceptionCache cleanup.
 514         ExceptionCache* next = ec->next();
 515         if (AtomicAccess::cmpxchg(&_exception_cache, ec, next) == ec) {
 516           CodeCache::release_exception_cache(ec);
 517         }
 518         continue;
 519       }
 520       ec = exception_cache();
 521       if (ec != nullptr) {
 522         new_entry->set_next(ec);
 523       }
 524     }
 525     if (AtomicAccess::cmpxchg(&_exception_cache, ec, new_entry) == ec) {
 526       return;
 527     }
 528   }
 529 }
 530 
 531 void nmethod::clean_exception_cache() {
 532   // For each nmethod, only a single thread may call this cleanup function
 533   // at the same time, whether called in STW cleanup or concurrent cleanup.
 534   // Note that if the GC is processing exception cache cleaning in a concurrent phase,
 535   // then a single writer may contend with cleaning up the head pointer to the
 536   // first ExceptionCache node that has a Klass* that is alive. That is fine,
 537   // as long as there is no concurrent cleanup of next pointers from concurrent writers.
 538   // And the concurrent writers do not clean up next pointers, only the head.
 539   // Also note that concurrent readers will walk through Klass* pointers that are not
 540   // alive. That does not cause ABA problems, because Klass* is deleted after
 541   // a handshake with all threads, after all stale ExceptionCaches have been
 542   // unlinked. That is also when the CodeCache::exception_cache_purge_list()
 543   // is deleted, with all ExceptionCache entries that were cleaned concurrently.
 544   // That similarly implies that CAS operations on ExceptionCache entries do not
 545   // suffer from ABA problems as unlinking and deletion is separated by a global
 546   // handshake operation.
 547   ExceptionCache* prev = nullptr;
 548   ExceptionCache* curr = exception_cache_acquire();
 549 
 550   while (curr != nullptr) {
 551     ExceptionCache* next = curr->next();
 552 
 553     if (!curr->exception_type()->is_loader_alive()) {
 554       if (prev == nullptr) {
 555         // Try to clean head; this is contended by concurrent inserts, that
 556         // both lazily clean the head, and insert entries at the head. If
 557         // the CAS fails, the operation is restarted.
 558         if (AtomicAccess::cmpxchg(&_exception_cache, curr, next) != curr) {
 559           prev = nullptr;
 560           curr = exception_cache_acquire();
 561           continue;
 562         }
 563       } else {
 564         // It is impossible to during cleanup connect the next pointer to
 565         // an ExceptionCache that has not been published before a safepoint
 566         // prior to the cleanup. Therefore, release is not required.
 567         prev->set_next(next);
 568       }
 569       // prev stays the same.
 570 
 571       CodeCache::release_exception_cache(curr);
 572     } else {
 573       prev = curr;
 574     }
 575 
 576     curr = next;
 577   }
 578 }
 579 
 580 // public method for accessing the exception cache
 581 // These are the public access methods.
 582 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
 583   // We never grab a lock to read the exception cache, so we may
 584   // have false negatives. This is okay, as it can only happen during
 585   // the first few exception lookups for a given nmethod.
 586   ExceptionCache* ec = exception_cache_acquire();
 587   while (ec != nullptr) {
 588     address ret_val;
 589     if ((ret_val = ec->match(exception,pc)) != nullptr) {
 590       return ret_val;
 591     }
 592     ec = ec->next();
 593   }
 594   return nullptr;
 595 }
 596 
 597 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
 598   // There are potential race conditions during exception cache updates, so we
 599   // must own the ExceptionCache_lock before doing ANY modifications. Because
 600   // we don't lock during reads, it is possible to have several threads attempt
 601   // to update the cache with the same data. We need to check for already inserted
 602   // copies of the current data before adding it.
 603 
 604   MutexLocker ml(ExceptionCache_lock);
 605   ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
 606 
 607   if (target_entry == nullptr || !target_entry->add_address_and_handler(pc,handler)) {
 608     target_entry = new ExceptionCache(exception,pc,handler);
 609     add_exception_cache_entry(target_entry);
 610   }
 611 }
 612 
 613 // private method for handling exception cache
 614 // These methods are private, and used to manipulate the exception cache
 615 // directly.
 616 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
 617   ExceptionCache* ec = exception_cache_acquire();
 618   while (ec != nullptr) {
 619     if (ec->match_exception_with_space(exception)) {
 620       return ec;
 621     }
 622     ec = ec->next();
 623   }
 624   return nullptr;
 625 }
 626 
 627 bool nmethod::is_at_poll_return(address pc) {
 628   RelocIterator iter(this, pc, pc+1);
 629   while (iter.next()) {
 630     if (iter.type() == relocInfo::poll_return_type)
 631       return true;
 632   }
 633   return false;
 634 }
 635 
 636 
 637 bool nmethod::is_at_poll_or_poll_return(address pc) {
 638   RelocIterator iter(this, pc, pc+1);
 639   while (iter.next()) {
 640     relocInfo::relocType t = iter.type();
 641     if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
 642       return true;
 643   }
 644   return false;
 645 }
 646 
 647 void nmethod::verify_oop_relocations() {
 648   // Ensure sure that the code matches the current oop values
 649   RelocIterator iter(this, nullptr, nullptr);
 650   while (iter.next()) {
 651     if (iter.type() == relocInfo::oop_type) {
 652       oop_Relocation* reloc = iter.oop_reloc();
 653       if (!reloc->oop_is_immediate()) {
 654         reloc->verify_oop_relocation();
 655       }
 656     }
 657   }
 658 }
 659 
 660 
 661 ScopeDesc* nmethod::scope_desc_at(address pc) {
 662   PcDesc* pd = pc_desc_at(pc);
 663   guarantee(pd != nullptr, "scope must be present");
 664   return new ScopeDesc(this, pd);
 665 }
 666 
 667 ScopeDesc* nmethod::scope_desc_near(address pc) {
 668   PcDesc* pd = pc_desc_near(pc);
 669   guarantee(pd != nullptr, "scope must be present");
 670   return new ScopeDesc(this, pd);
 671 }
 672 
 673 address nmethod::oops_reloc_begin() const {
 674   // If the method is not entrant then a JMP is plastered over the
 675   // first few bytes.  If an oop in the old code was there, that oop
 676   // should not get GC'd.  Skip the first few bytes of oops on
 677   // not-entrant methods.
 678   if (frame_complete_offset() != CodeOffsets::frame_never_safe &&
 679       code_begin() + frame_complete_offset() >
 680       verified_entry_point() + NativeJump::instruction_size)
 681   {
 682     // If we have a frame_complete_offset after the native jump, then there
 683     // is no point trying to look for oops before that. This is a requirement
 684     // for being allowed to scan oops concurrently.
 685     return code_begin() + frame_complete_offset();
 686   }
 687 
 688   address low_boundary = verified_entry_point();
 689   return low_boundary;
 690 }
 691 
 692 // Method that knows how to preserve outgoing arguments at call. This method must be
 693 // called with a frame corresponding to a Java invoke
 694 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
 695   if (method() == nullptr) {
 696     return;
 697   }
 698 
 699   // handle the case of an anchor explicitly set in continuation code that doesn't have a callee
 700   JavaThread* thread = reg_map->thread();
 701   if ((thread->has_last_Java_frame() && fr.sp() == thread->last_Java_sp())
 702       JVMTI_ONLY(|| (method()->is_continuation_enter_intrinsic() && thread->on_monitor_waited_event()))) {
 703     return;
 704   }
 705 
 706   if (!method()->is_native()) {
 707     address pc = fr.pc();
 708     bool has_receiver, has_appendix;
 709     Symbol* signature;
 710 
 711     // The method attached by JIT-compilers should be used, if present.
 712     // Bytecode can be inaccurate in such case.
 713     Method* callee = attached_method_before_pc(pc);
 714     if (callee != nullptr) {
 715       has_receiver = !(callee->access_flags().is_static());
 716       has_appendix = false;
 717       signature    = callee->signature();
 718     } else {
 719       SimpleScopeDesc ssd(this, pc);
 720 
 721       Bytecode_invoke call(methodHandle(Thread::current(), ssd.method()), ssd.bci());
 722       has_receiver = call.has_receiver();
 723       has_appendix = call.has_appendix();
 724       signature    = call.signature();
 725     }
 726 
 727     fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
 728   } else if (method()->is_continuation_enter_intrinsic()) {
 729     // This method only calls Continuation.enter()
 730     Symbol* signature = vmSymbols::continuationEnter_signature();
 731     fr.oops_compiled_arguments_do(signature, false, false, reg_map, f);
 732   }
 733 }
 734 
 735 Method* nmethod::attached_method(address call_instr) {
 736   assert(code_contains(call_instr), "not part of the nmethod");
 737   RelocIterator iter(this, call_instr, call_instr + 1);
 738   while (iter.next()) {
 739     if (iter.addr() == call_instr) {
 740       switch(iter.type()) {
 741         case relocInfo::static_call_type:      return iter.static_call_reloc()->method_value();
 742         case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
 743         case relocInfo::virtual_call_type:     return iter.virtual_call_reloc()->method_value();
 744         default:                               break;
 745       }
 746     }
 747   }
 748   return nullptr; // not found
 749 }
 750 
 751 Method* nmethod::attached_method_before_pc(address pc) {
 752   if (NativeCall::is_call_before(pc)) {
 753     NativeCall* ncall = nativeCall_before(pc);
 754     return attached_method(ncall->instruction_address());
 755   }
 756   return nullptr; // not a call
 757 }
 758 
 759 void nmethod::clear_inline_caches() {
 760   assert(SafepointSynchronize::is_at_safepoint() || (NMethodState_lock->owned_by_self() && is_not_installed()), "clearing of IC's only allowed at safepoint or when not installed");
 761   RelocIterator iter(this);
 762   while (iter.next()) {
 763     iter.reloc()->clear_inline_cache();
 764   }
 765 }
 766 
 767 #ifdef ASSERT
 768 // Check class_loader is alive for this bit of metadata.
 769 class CheckClass : public MetadataClosure {
 770   void do_metadata(Metadata* md) {
 771     Klass* klass = nullptr;
 772     if (md->is_klass()) {
 773       klass = ((Klass*)md);
 774     } else if (md->is_method()) {
 775       klass = ((Method*)md)->method_holder();
 776     } else if (md->is_methodData()) {
 777       klass = ((MethodData*)md)->method()->method_holder();
 778     } else if (md->is_methodCounters()) {
 779       klass = ((MethodCounters*)md)->method()->method_holder();
 780     } else {
 781       md->print();
 782       ShouldNotReachHere();
 783     }
 784     assert(klass->is_loader_alive(), "must be alive");
 785   }
 786 };
 787 #endif // ASSERT
 788 
 789 // Clean references to unloaded nmethods at addr from this one, which is not unloaded.
 790 template <typename CallsiteT>
 791 static void clean_if_nmethod_is_unloaded(CallsiteT* callsite, bool clean_all) {
 792   CodeBlob* cb = CodeCache::find_blob(callsite->destination());
 793   if (!cb->is_nmethod()) {
 794     return;
 795   }
 796   nmethod* nm = cb->as_nmethod();
 797   if (clean_all || !nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
 798     callsite->set_to_clean();
 799   }
 800 }
 801 
 802 // Cleans caches in nmethods that point to either classes that are unloaded
 803 // or nmethods that are unloaded.
 804 //
 805 // Can be called either in parallel by G1 currently or after all
 806 // nmethods are unloaded.  Return postponed=true in the parallel case for
 807 // inline caches found that point to nmethods that are not yet visited during
 808 // the do_unloading walk.
 809 void nmethod::unload_nmethod_caches(bool unloading_occurred) {
 810   ResourceMark rm;
 811 
 812   // Exception cache only needs to be called if unloading occurred
 813   if (unloading_occurred) {
 814     clean_exception_cache();
 815   }
 816 
 817   cleanup_inline_caches_impl(unloading_occurred, false);
 818 
 819 #ifdef ASSERT
 820   // Check that the metadata embedded in the nmethod is alive
 821   CheckClass check_class;
 822   metadata_do(&check_class);
 823 #endif
 824 }
 825 
 826 void nmethod::run_nmethod_entry_barrier() {
 827   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
 828   if (bs_nm != nullptr) {
 829     // We want to keep an invariant that nmethods found through iterations of a Thread's
 830     // nmethods found in safepoints have gone through an entry barrier and are not armed.
 831     // By calling this nmethod entry barrier, it plays along and acts
 832     // like any other nmethod found on the stack of a thread (fewer surprises).
 833     nmethod* nm = this;
 834     bool alive = bs_nm->nmethod_entry_barrier(nm);
 835     assert(alive, "should be alive");
 836   }
 837 }
 838 
 839 // Only called by whitebox test
 840 void nmethod::cleanup_inline_caches_whitebox() {
 841   assert_locked_or_safepoint(CodeCache_lock);
 842   CompiledICLocker ic_locker(this);
 843   cleanup_inline_caches_impl(false /* unloading_occurred */, true /* clean_all */);
 844 }
 845 
 846 address* nmethod::orig_pc_addr(const frame* fr) {
 847   return (address*) ((address)fr->unextended_sp() + orig_pc_offset());
 848 }
 849 
 850 // Called to clean up after class unloading for live nmethods
 851 void nmethod::cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all) {
 852   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
 853   ResourceMark rm;
 854 
 855   // Find all calls in an nmethod and clear the ones that point to bad nmethods.
 856   RelocIterator iter(this, oops_reloc_begin());
 857   bool is_in_static_stub = false;
 858   while(iter.next()) {
 859 
 860     switch (iter.type()) {
 861 
 862     case relocInfo::virtual_call_type:
 863       if (unloading_occurred) {
 864         // If class unloading occurred we first clear ICs where the cached metadata
 865         // is referring to an unloaded klass or method.
 866         CompiledIC_at(&iter)->clean_metadata();
 867       }
 868 
 869       clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), clean_all);
 870       break;
 871 
 872     case relocInfo::opt_virtual_call_type:
 873     case relocInfo::static_call_type:
 874       clean_if_nmethod_is_unloaded(CompiledDirectCall::at(iter.reloc()), clean_all);
 875       break;
 876 
 877     case relocInfo::static_stub_type: {
 878       is_in_static_stub = true;
 879       break;
 880     }
 881 
 882     case relocInfo::metadata_type: {
 883       // Only the metadata relocations contained in static/opt virtual call stubs
 884       // contains the Method* passed to c2i adapters. It is the only metadata
 885       // relocation that needs to be walked, as it is the one metadata relocation
 886       // that violates the invariant that all metadata relocations have an oop
 887       // in the compiled method (due to deferred resolution and code patching).
 888 
 889       // This causes dead metadata to remain in compiled methods that are not
 890       // unloading. Unless these slippery metadata relocations of the static
 891       // stubs are at least cleared, subsequent class redefinition operations
 892       // will access potentially free memory, and JavaThread execution
 893       // concurrent to class unloading may call c2i adapters with dead methods.
 894       if (!is_in_static_stub) {
 895         // The first metadata relocation after a static stub relocation is the
 896         // metadata relocation of the static stub used to pass the Method* to
 897         // c2i adapters.
 898         continue;
 899       }
 900       is_in_static_stub = false;
 901       if (is_unloading()) {
 902         // If the nmethod itself is dying, then it may point at dead metadata.
 903         // Nobody should follow that metadata; it is strictly unsafe.
 904         continue;
 905       }
 906       metadata_Relocation* r = iter.metadata_reloc();
 907       Metadata* md = r->metadata_value();
 908       if (md != nullptr && md->is_method()) {
 909         Method* method = static_cast<Method*>(md);
 910         if (!method->method_holder()->is_loader_alive()) {
 911           AtomicAccess::store(r->metadata_addr(), (Method*)nullptr);
 912 
 913           if (!r->metadata_is_immediate()) {
 914             r->fix_metadata_relocation();
 915           }
 916         }
 917       }
 918       break;
 919     }
 920 
 921     default:
 922       break;
 923     }
 924   }
 925 }
 926 
 927 address nmethod::continuation_for_implicit_exception(address pc, bool for_div0_check) {
 928   // Exception happened outside inline-cache check code => we are inside
 929   // an active nmethod => use cpc to determine a return address
 930   int exception_offset = int(pc - code_begin());
 931   int cont_offset = ImplicitExceptionTable(this).continuation_offset( exception_offset );
 932 #ifdef ASSERT
 933   if (cont_offset == 0) {
 934     Thread* thread = Thread::current();
 935     ResourceMark rm(thread);
 936     CodeBlob* cb = CodeCache::find_blob(pc);
 937     assert(cb != nullptr && cb == this, "");
 938 
 939     // Keep tty output consistent. To avoid ttyLocker, we buffer in stream, and print all at once.
 940     stringStream ss;
 941     ss.print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
 942     print_on(&ss);
 943     // Buffering to a stringStream, disable internal buffering so it's not done twice.
 944     method()->print_codes_on(&ss, 0, false);
 945     print_code_on(&ss);
 946     print_pcs_on(&ss);
 947     tty->print("%s", ss.as_string()); // print all at once
 948   }
 949 #endif
 950   if (cont_offset == 0) {
 951     // Let the normal error handling report the exception
 952     return nullptr;
 953   }
 954   if (cont_offset == exception_offset) {
 955 #if INCLUDE_JVMCI
 956     Deoptimization::DeoptReason deopt_reason = for_div0_check ? Deoptimization::Reason_div0_check : Deoptimization::Reason_null_check;
 957     JavaThread *thread = JavaThread::current();
 958     thread->set_jvmci_implicit_exception_pc(pc);
 959     thread->set_pending_deoptimization(Deoptimization::make_trap_request(deopt_reason,
 960                                                                          Deoptimization::Action_reinterpret));
 961     return (SharedRuntime::deopt_blob()->implicit_exception_uncommon_trap());
 962 #else
 963     ShouldNotReachHere();
 964 #endif
 965   }
 966   return code_begin() + cont_offset;
 967 }
 968 
 969 class HasEvolDependency : public MetadataClosure {
 970   bool _has_evol_dependency;
 971  public:
 972   HasEvolDependency() : _has_evol_dependency(false) {}
 973   void do_metadata(Metadata* md) {
 974     if (md->is_method()) {
 975       Method* method = (Method*)md;
 976       if (method->is_old()) {
 977         _has_evol_dependency = true;
 978       }
 979     }
 980   }
 981   bool has_evol_dependency() const { return _has_evol_dependency; }
 982 };
 983 
 984 bool nmethod::has_evol_metadata() {
 985   // Check the metadata in relocIter and CompiledIC and also deoptimize
 986   // any nmethod that has reference to old methods.
 987   HasEvolDependency check_evol;
 988   metadata_do(&check_evol);
 989   if (check_evol.has_evol_dependency() && log_is_enabled(Debug, redefine, class, nmethod)) {
 990     ResourceMark rm;
 991     log_debug(redefine, class, nmethod)
 992             ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on in nmethod metadata",
 993              _method->method_holder()->external_name(),
 994              _method->name()->as_C_string(),
 995              _method->signature()->as_C_string(),
 996              compile_id());
 997   }
 998   return check_evol.has_evol_dependency();
 999 }
1000 
1001 int nmethod::total_size() const {
1002   return
1003     consts_size()        +
1004     insts_size()         +
1005     stub_size()          +
1006     scopes_data_size()   +
1007     scopes_pcs_size()    +
1008     handler_table_size() +
1009     nul_chk_table_size();
1010 }
1011 
1012 const char* nmethod::compile_kind() const {
1013   if (is_osr_method()) return "osr";
1014   if (preloaded())     return "AP";
1015   if (is_aot())        return "A";
1016 
1017   if (method() != nullptr && is_native_method()) {
1018     if (method()->is_continuation_native_intrinsic()) {
1019       return "cnt";
1020     }
1021     return "c2n";
1022   }
1023   return "";
1024 }
1025 
1026 const char* nmethod::compiler_name() const {
1027   return compilertype2name(_compiler_type);
1028 }
1029 
1030 #ifdef ASSERT
1031 class CheckForOopsClosure : public OopClosure {
1032   bool _found_oop = false;
1033  public:
1034   virtual void do_oop(oop* o) { _found_oop = true; }
1035   virtual void do_oop(narrowOop* o) { _found_oop = true; }
1036   bool found_oop() { return _found_oop; }
1037 };
1038 class CheckForMetadataClosure : public MetadataClosure {
1039   bool _found_metadata = false;
1040   Metadata* _ignore = nullptr;
1041  public:
1042   CheckForMetadataClosure(Metadata* ignore) : _ignore(ignore) {}
1043   virtual void do_metadata(Metadata* md) { if (md != _ignore) _found_metadata = true; }
1044   bool found_metadata() { return _found_metadata; }
1045 };
1046 
1047 static void assert_no_oops_or_metadata(nmethod* nm) {
1048   if (nm == nullptr) return;
1049   assert(nm->oop_maps() == nullptr, "expectation");
1050 
1051   CheckForOopsClosure cfo;
1052   nm->oops_do(&cfo);
1053   assert(!cfo.found_oop(), "no oops allowed");
1054 
1055   // We allow an exception for the own Method, but require its class to be permanent.
1056   Method* own_method = nm->method();
1057   CheckForMetadataClosure cfm(/* ignore reference to own Method */ own_method);
1058   nm->metadata_do(&cfm);
1059   assert(!cfm.found_metadata(), "no metadata allowed");
1060 
1061   assert(own_method->method_holder()->class_loader_data()->is_permanent_class_loader_data(),
1062          "Method's class needs to be permanent");
1063 }
1064 #endif
1065 
1066 static int required_mutable_data_size(CodeBuffer* code_buffer,
1067                                       int jvmci_data_size = 0) {
1068   return align_up(code_buffer->total_relocation_size(), oopSize) +
1069          align_up(code_buffer->total_metadata_size(), oopSize) +
1070          align_up(jvmci_data_size, oopSize);
1071 }
1072 
1073 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
1074   int compile_id,
1075   CodeBuffer *code_buffer,
1076   int vep_offset,
1077   int frame_complete,
1078   int frame_size,
1079   ByteSize basic_lock_owner_sp_offset,
1080   ByteSize basic_lock_sp_offset,
1081   OopMapSet* oop_maps,
1082   int exception_handler) {
1083   code_buffer->finalize_oop_references(method);
1084   // create nmethod
1085   nmethod* nm = nullptr;
1086   int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1087   {
1088     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1089 
1090     CodeOffsets offsets;
1091     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
1092     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
1093     if (exception_handler != -1) {
1094       offsets.set_value(CodeOffsets::Exceptions, exception_handler);
1095     }
1096 
1097     int mutable_data_size = required_mutable_data_size(code_buffer);
1098 
1099     // MH intrinsics are dispatch stubs which are compatible with NonNMethod space.
1100     // IsUnloadingBehaviour::is_unloading needs to handle them separately.
1101     bool allow_NonNMethod_space = method->can_be_allocated_in_NonNMethod_space();
1102     nm = new (native_nmethod_size, allow_NonNMethod_space)
1103     nmethod(method(), compiler_none, native_nmethod_size,
1104             compile_id, &offsets,
1105             code_buffer, frame_size,
1106             basic_lock_owner_sp_offset,
1107             basic_lock_sp_offset,
1108             oop_maps, mutable_data_size);
1109     DEBUG_ONLY( if (allow_NonNMethod_space) assert_no_oops_or_metadata(nm); )
1110     NOT_PRODUCT(if (nm != nullptr) native_nmethod_stats.note_native_nmethod(nm));
1111   }
1112 
1113   if (nm != nullptr) {
1114     // verify nmethod
1115     DEBUG_ONLY(nm->verify();) // might block
1116 
1117     nm->log_new_nmethod();
1118   }
1119   return nm;
1120 }
1121 
1122 void nmethod::record_nmethod_dependency() {
1123   // To make dependency checking during class loading fast, record
1124   // the nmethod dependencies in the classes it is dependent on.
1125   // This allows the dependency checking code to simply walk the
1126   // class hierarchy above the loaded class, checking only nmethods
1127   // which are dependent on those classes.  The slow way is to
1128   // check every nmethod for dependencies which makes it linear in
1129   // the number of methods compiled.  For applications with a lot
1130   // classes the slow way is too slow.
1131   for (Dependencies::DepStream deps(this); deps.next(); ) {
1132     if (deps.type() == Dependencies::call_site_target_value) {
1133       // CallSite dependencies are managed on per-CallSite instance basis.
1134       oop call_site = deps.argument_oop(0);
1135       MethodHandles::add_dependent_nmethod(call_site, this);
1136     } else {
1137       InstanceKlass* ik = deps.context_type();
1138       if (ik == nullptr) {
1139         continue;  // ignore things like evol_method
1140       }
1141       // record this nmethod as dependent on this klass
1142       ik->add_dependent_nmethod(this);
1143     }
1144   }
1145 }
1146 
1147 nmethod* nmethod::new_nmethod(const methodHandle& method,
1148   int compile_id,
1149   int entry_bci,
1150   CodeOffsets* offsets,
1151   int orig_pc_offset,
1152   DebugInformationRecorder* debug_info,
1153   Dependencies* dependencies,
1154   CodeBuffer* code_buffer, int frame_size,
1155   OopMapSet* oop_maps,
1156   ExceptionHandlerTable* handler_table,
1157   ImplicitExceptionTable* nul_chk_table,
1158   AbstractCompiler* compiler,
1159   CompLevel comp_level
1160 #if INCLUDE_JVMCI
1161   , char* speculations,
1162   int speculations_len,
1163   JVMCINMethodData* jvmci_data
1164 #endif
1165 )
1166 {
1167   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1168   code_buffer->finalize_oop_references(method);
1169   // create nmethod
1170   nmethod* nm = nullptr;
1171   int nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1172 
1173   int immutable_data_size =
1174       adjust_pcs_size(debug_info->pcs_size())
1175     + align_up((int)dependencies->size_in_bytes(), oopSize)
1176     + align_up(handler_table->size_in_bytes()    , oopSize)
1177     + align_up(nul_chk_table->size_in_bytes()    , oopSize)
1178 #if INCLUDE_JVMCI
1179     + align_up(speculations_len                  , oopSize)
1180 #endif
1181     + align_up(debug_info->data_size()           , oopSize);
1182 
1183   // First, allocate space for immutable data in C heap.
1184   address immutable_data = nullptr;
1185   if (immutable_data_size > 0) {
1186     immutable_data_size += ImmutableDataRefCountSize;
1187     immutable_data = (address)os::malloc(immutable_data_size, mtCode);
1188     if (immutable_data == nullptr) {
1189       vm_exit_out_of_memory(immutable_data_size, OOM_MALLOC_ERROR, "nmethod: no space for immutable data");
1190       return nullptr;
1191     }
1192   }
1193 
1194   int mutable_data_size = required_mutable_data_size(code_buffer
1195     JVMCI_ONLY(COMMA (compiler->is_jvmci() ? jvmci_data->size() : 0)));
1196 
1197   {
1198     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1199 
1200     nm = new (nmethod_size, comp_level)
1201     nmethod(method(), compiler->type(), nmethod_size, immutable_data_size, mutable_data_size,
1202             compile_id, entry_bci, immutable_data, offsets, orig_pc_offset,
1203             debug_info, dependencies, code_buffer, frame_size, oop_maps,
1204             handler_table, nul_chk_table, compiler, comp_level
1205 #if INCLUDE_JVMCI
1206             , speculations,
1207             speculations_len,
1208             jvmci_data
1209 #endif
1210             );
1211 
1212     if (nm != nullptr) {
1213       nm->record_nmethod_dependency();
1214       NOT_PRODUCT(note_java_nmethod(nm));
1215     }
1216   }
1217   // Do verification and logging outside CodeCache_lock.
1218   if (nm != nullptr) {
1219 
1220 #ifdef ASSERT
1221     LogTarget(Debug, aot, codecache, nmethod) log;
1222     if (log.is_enabled()) {
1223       LogStream out(log);
1224       out.print_cr("== new_nmethod 2");
1225       FlagSetting fs(PrintRelocations, true);
1226       nm->print_on_impl(&out);
1227       nm->decode(&out);
1228     }
1229 #endif
1230 
1231     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
1232     DEBUG_ONLY(nm->verify();)
1233     nm->log_new_nmethod();
1234   }
1235   return nm;
1236 }
1237 
1238 nmethod* nmethod::restore(address code_cache_buffer,
1239                           const methodHandle& method,
1240                           int compile_id,
1241                           address reloc_data,
1242                           GrowableArray<Handle>& oop_list,
1243                           GrowableArray<Metadata*>& metadata_list,
1244                           ImmutableOopMapSet* oop_maps,
1245                           address immutable_data,
1246                           GrowableArray<Handle>& reloc_imm_oop_list,
1247                           GrowableArray<Metadata*>& reloc_imm_metadata_list,
1248                           AOTCodeReader* aot_code_reader)
1249 {
1250   CodeBlob::restore(code_cache_buffer, "nmethod", reloc_data, oop_maps);
1251   nmethod* nm = (nmethod*)code_cache_buffer;
1252   nm->set_method(method());
1253   nm->_compile_id = compile_id;
1254   nm->set_immutable_data(immutable_data);
1255   nm->copy_values(&oop_list);
1256   nm->copy_values(&metadata_list);
1257 
1258   aot_code_reader->fix_relocations(nm, &reloc_imm_oop_list, &reloc_imm_metadata_list);
1259 
1260 #ifndef PRODUCT
1261   nm->asm_remarks().init();
1262   aot_code_reader->read_asm_remarks(nm->asm_remarks(), /* use_string_table */ false);
1263   nm->dbg_strings().init();
1264   aot_code_reader->read_dbg_strings(nm->dbg_strings(), /* use_string_table */ false);
1265 #endif
1266 
1267   // Flush the code block
1268   ICache::invalidate_range(nm->code_begin(), nm->code_size());
1269 
1270   // Create cache after PcDesc data is copied - it will be used to initialize cache
1271   nm->_pc_desc_container = new PcDescContainer(nm->scopes_pcs_begin());
1272 
1273   nm->set_aot_code_entry(aot_code_reader->aot_code_entry());
1274 
1275   nm->post_init();
1276   return nm;
1277 }
1278 
1279 nmethod* nmethod::new_nmethod(nmethod* archived_nm,
1280                               const methodHandle& method,
1281                               AbstractCompiler* compiler,
1282                               int compile_id,
1283                               address reloc_data,
1284                               GrowableArray<Handle>& oop_list,
1285                               GrowableArray<Metadata*>& metadata_list,
1286                               ImmutableOopMapSet* oop_maps,
1287                               address immutable_data,
1288                               GrowableArray<Handle>& reloc_imm_oop_list,
1289                               GrowableArray<Metadata*>& reloc_imm_metadata_list,
1290                               AOTCodeReader* aot_code_reader)
1291 {
1292   nmethod* nm = nullptr;
1293   int nmethod_size = archived_nm->size();
1294   // create nmethod
1295   {
1296     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1297     address code_cache_buffer = (address)CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(archived_nm->comp_level()));
1298     if (code_cache_buffer != nullptr) {
1299       nm = archived_nm->restore(code_cache_buffer,
1300                                 method,
1301                                 compile_id,
1302                                 reloc_data,
1303                                 oop_list,
1304                                 metadata_list,
1305                                 oop_maps,
1306                                 immutable_data,
1307                                 reloc_imm_oop_list,
1308                                 reloc_imm_metadata_list,
1309                                 aot_code_reader);
1310       nm->record_nmethod_dependency();
1311       NOT_PRODUCT(note_java_nmethod(nm));
1312     }
1313   }
1314   // Do verification and logging outside CodeCache_lock.
1315   if (nm != nullptr) {
1316 #ifdef ASSERT
1317     LogTarget(Debug, aot, codecache, nmethod) log;
1318     if (log.is_enabled()) {
1319       LogStream out(log);
1320       out.print_cr("== new_nmethod 2");
1321       FlagSetting fs(PrintRelocations, true);
1322       nm->print_on_impl(&out);
1323       nm->decode(&out);
1324     }
1325 #endif
1326     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
1327     DEBUG_ONLY(nm->verify();)
1328     nm->log_new_nmethod();
1329   }
1330   return nm;
1331 }
1332 
1333 // Fill in default values for various fields
1334 void nmethod::init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets) {
1335   // avoid uninitialized fields, even for short time periods
1336   _exception_cache            = nullptr;
1337   _gc_data                    = nullptr;
1338   _oops_do_mark_link          = nullptr;
1339   _compiled_ic_data           = nullptr;
1340   _aot_code_entry             = nullptr;
1341 
1342   _is_unloading_state         = 0;
1343   _state                      = not_installed;
1344 
1345   _has_unsafe_access          = 0;
1346   _has_wide_vectors           = 0;
1347   _has_monitors               = 0;
1348   _has_scoped_access          = 0;
1349   _has_flushed_dependencies   = 0;
1350   _is_unlinked                = 0;
1351   _load_reported              = 0; // jvmti state
1352   _preloaded                  = 0;
1353   _has_clinit_barriers        = 0;
1354 
1355   _used                       = false;
1356   _deoptimization_status      = not_marked;
1357 
1358   // SECT_CONSTS is first in code buffer so the offset should be 0.
1359   int consts_offset = code_buffer->total_offset_of(code_buffer->consts());
1360   assert(consts_offset == 0, "const_offset: %d", consts_offset);
1361 
1362   _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
1363 
1364   CHECKED_CAST(_entry_offset,              uint16_t, (offsets->value(CodeOffsets::Entry)));
1365   CHECKED_CAST(_verified_entry_offset,     uint16_t, (offsets->value(CodeOffsets::Verified_Entry)));
1366 
1367   _skipped_instructions_size = code_buffer->total_skipped_instructions_size();
1368 }
1369 
1370 // Post initialization
1371 void nmethod::post_init() {
1372   clear_unloading_state();
1373 
1374   finalize_relocations();
1375 
1376   Universe::heap()->register_nmethod(this);
1377   DEBUG_ONLY(Universe::heap()->verify_nmethod(this));
1378 
1379   CodeCache::commit(this);
1380 }
1381 
1382 // For native wrappers
1383 nmethod::nmethod(
1384   Method* method,
1385   CompilerType type,
1386   int nmethod_size,
1387   int compile_id,
1388   CodeOffsets* offsets,
1389   CodeBuffer* code_buffer,
1390   int frame_size,
1391   ByteSize basic_lock_owner_sp_offset,
1392   ByteSize basic_lock_sp_offset,
1393   OopMapSet* oop_maps,
1394   int mutable_data_size)
1395   : CodeBlob("native nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1396              offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, mutable_data_size),
1397   _deoptimization_generation(0),
1398   _gc_epoch(CodeCache::gc_epoch()),
1399   _method(method),
1400   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
1401   _native_basic_lock_sp_offset(basic_lock_sp_offset)
1402 {
1403   {
1404     DEBUG_ONLY(NoSafepointVerifier nsv;)
1405     assert_locked_or_safepoint(CodeCache_lock);
1406 
1407     init_defaults(code_buffer, offsets);
1408 
1409     _osr_entry_point         = nullptr;
1410     _pc_desc_container       = nullptr;
1411     _entry_bci               = InvocationEntryBci;
1412     _compile_id              = compile_id;
1413     _comp_level              = CompLevel_none;
1414     _compiler_type           = type;
1415     _orig_pc_offset          = 0;
1416     _num_stack_arg_slots     = 0;
1417 
1418     if (offsets->value(CodeOffsets::Exceptions) != -1) {
1419       // Continuation enter intrinsic
1420       _exception_offset      = code_offset() + offsets->value(CodeOffsets::Exceptions);
1421     } else {
1422       _exception_offset      = 0;
1423     }
1424     // Native wrappers do not have deopt handlers. Make the values
1425     // something that will never match a pc like the nmethod vtable entry
1426     _deopt_handler_entry_offset    = 0;
1427     _method_profiling_count  = 0;
1428     _unwind_handler_offset   = 0;
1429 
1430     CHECKED_CAST(_oops_size, uint16_t, align_up(code_buffer->total_oop_size(), oopSize));
1431     uint16_t metadata_size;
1432     CHECKED_CAST(metadata_size, uint16_t, align_up(code_buffer->total_metadata_size(), wordSize));
1433     JVMCI_ONLY( _metadata_size = metadata_size; )
1434     assert(_mutable_data_size == _relocation_size + metadata_size,
1435            "wrong mutable data size: %d != %d + %d",
1436            _mutable_data_size, _relocation_size, metadata_size);
1437 
1438     // native wrapper does not have read-only data but we need unique not null address
1439     _immutable_data          = blob_end();
1440     _immutable_data_size     = 0;
1441     _nul_chk_table_offset    = 0;
1442     _handler_table_offset    = 0;
1443     _scopes_pcs_offset       = 0;
1444     _scopes_data_offset      = 0;
1445 #if INCLUDE_JVMCI
1446     _speculations_offset     = 0;
1447 #endif
1448     _immutable_data_ref_count_offset = 0;
1449 
1450     code_buffer->copy_code_and_locs_to(this);
1451     code_buffer->copy_values_to(this);
1452 
1453     post_init();
1454   }
1455 
1456   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
1457     ttyLocker ttyl;  // keep the following output all in one block
1458     // This output goes directly to the tty, not the compiler log.
1459     // To enable tools to match it up with the compilation activity,
1460     // be sure to tag this tty output with the compile ID.
1461     if (xtty != nullptr) {
1462       xtty->begin_head("print_native_nmethod");
1463       xtty->method(_method);
1464       xtty->stamp();
1465       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
1466     }
1467     // Print the header part, then print the requested information.
1468     // This is both handled in decode2(), called via print_code() -> decode()
1469     if (PrintNativeNMethods) {
1470       tty->print_cr("-------------------------- Assembly (native nmethod) ---------------------------");
1471       print_code();
1472       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1473 #if defined(SUPPORT_DATA_STRUCTS)
1474       if (AbstractDisassembler::show_structs()) {
1475         if (oop_maps != nullptr) {
1476           tty->print("oop maps:"); // oop_maps->print_on(tty) outputs a cr() at the beginning
1477           oop_maps->print_on(tty);
1478           tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1479         }
1480       }
1481 #endif
1482     } else {
1483       print(); // print the header part only.
1484     }
1485 #if defined(SUPPORT_DATA_STRUCTS)
1486     if (AbstractDisassembler::show_structs()) {
1487       if (PrintRelocations) {
1488         print_relocations_on(tty);
1489         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1490       }
1491     }
1492 #endif
1493     if (xtty != nullptr) {
1494       xtty->tail("print_native_nmethod");
1495     }
1496   }
1497 }
1498 
1499 
1500 nmethod::nmethod(const nmethod &nm) : CodeBlob(nm._name, nm._kind, nm._size, nm._header_size)
1501 {
1502 
1503   if (nm._oop_maps != nullptr) {
1504     _oop_maps                   = nm._oop_maps->clone();
1505   } else {
1506     _oop_maps                   = nullptr;
1507   }
1508 
1509   _size                         = nm._size;
1510   _relocation_size              = nm._relocation_size;
1511   _content_offset               = nm._content_offset;
1512   _code_offset                  = nm._code_offset;
1513   _data_offset                  = nm._data_offset;
1514   _frame_size                   = nm._frame_size;
1515 
1516   S390_ONLY( _ctable_offset     = nm._ctable_offset; )
1517 
1518   _header_size                  = nm._header_size;
1519   _frame_complete_offset        = nm._frame_complete_offset;
1520 
1521   _kind                         = nm._kind;
1522 
1523   _caller_must_gc_arguments     = nm._caller_must_gc_arguments;
1524 
1525 #ifndef PRODUCT
1526   _asm_remarks.share(nm._asm_remarks);
1527   _dbg_strings.share(nm._dbg_strings);
1528 #endif
1529 
1530   // Allocate memory and copy mutable data to C heap
1531   _mutable_data_size            = nm._mutable_data_size;
1532   if (_mutable_data_size > 0) {
1533     _mutable_data = (address)os::malloc(_mutable_data_size, mtCode);
1534     if (_mutable_data == nullptr) {
1535       vm_exit_out_of_memory(_mutable_data_size, OOM_MALLOC_ERROR, "nmethod: no space for mutable data");
1536     }
1537     memcpy(mutable_data_begin(), nm.mutable_data_begin(), nm.mutable_data_size());
1538   } else {
1539     _mutable_data               = nullptr;
1540   }
1541 
1542   _deoptimization_generation    = 0;
1543   _gc_epoch                     = CodeCache::gc_epoch();
1544   _method                       = nm._method;
1545   _osr_link                     = nullptr;
1546 
1547   _exception_cache              = nullptr;
1548   _gc_data                      = nullptr;
1549   _oops_do_mark_nmethods        = nullptr;
1550   _oops_do_mark_link            = nullptr;
1551   _compiled_ic_data             = nullptr;
1552   _aot_code_entry               = nm._aot_code_entry;
1553 
1554   if (nm._osr_entry_point != nullptr) {
1555     _osr_entry_point            = (nm._osr_entry_point - (address) &nm) + (address) this;
1556   } else {
1557     _osr_entry_point            = nullptr;
1558   }
1559 
1560   _entry_offset                 = nm._entry_offset;
1561   _verified_entry_offset        = nm._verified_entry_offset;
1562   _entry_bci                    = nm._entry_bci;
1563   _immutable_data_size          = nm._immutable_data_size;
1564 
1565   _skipped_instructions_size    = nm._skipped_instructions_size;
1566   _stub_offset                  = nm._stub_offset;
1567   _exception_offset             = nm._exception_offset;
1568   _deopt_handler_entry_offset   = nm._deopt_handler_entry_offset;
1569   _unwind_handler_offset        = nm._unwind_handler_offset;
1570   _num_stack_arg_slots          = nm._num_stack_arg_slots;
1571   _oops_size                    = nm._oops_size;
1572 #if INCLUDE_JVMCI
1573   _metadata_size                = nm._metadata_size;
1574 #endif
1575   _nul_chk_table_offset         = nm._nul_chk_table_offset;
1576   _handler_table_offset         = nm._handler_table_offset;
1577   _scopes_pcs_offset            = nm._scopes_pcs_offset;
1578   _scopes_data_offset           = nm._scopes_data_offset;
1579 #if INCLUDE_JVMCI
1580   _speculations_offset          = nm._speculations_offset;
1581 #endif
1582   _immutable_data_ref_count_offset = nm._immutable_data_ref_count_offset;
1583 
1584   // Increment number of references to immutable data to share it between nmethods
1585   if (_immutable_data_size > 0) {
1586     _immutable_data             = nm._immutable_data;
1587     inc_immutable_data_ref_count();
1588   } else {
1589     _immutable_data             = blob_end();
1590   }
1591 
1592   _orig_pc_offset               = nm._orig_pc_offset;
1593   _compile_id                   = nm._compile_id;
1594   _comp_level                   = nm._comp_level;
1595   _compiler_type                = nm._compiler_type;
1596   _is_unloading_state           = nm._is_unloading_state;
1597   _state                        = not_installed;
1598 
1599   _has_unsafe_access            = nm._has_unsafe_access;
1600   _has_wide_vectors             = nm._has_wide_vectors;
1601   _has_monitors                 = nm._has_monitors;
1602   _has_scoped_access            = nm._has_scoped_access;
1603   _has_flushed_dependencies     = nm._has_flushed_dependencies;
1604   _is_unlinked                  = nm._is_unlinked;
1605   _load_reported                = nm._load_reported;
1606   _preloaded                    = nm._preloaded;
1607   _has_clinit_barriers          = nm._has_clinit_barriers;
1608 
1609   _deoptimization_status        = nm._deoptimization_status;
1610 
1611   if (nm._pc_desc_container != nullptr) {
1612     _pc_desc_container          = new PcDescContainer(scopes_pcs_begin());
1613   } else {
1614     _pc_desc_container          = nullptr;
1615   }
1616 
1617   // Copy nmethod contents excluding header
1618   // - Constant part          (doubles, longs and floats used in nmethod)
1619   // - Code part:
1620   //   - Code body
1621   //   - Exception handler
1622   //   - Stub code
1623   //   - OOP table
1624   memcpy(consts_begin(), nm.consts_begin(), nm.data_end() - nm.consts_begin());
1625 
1626   // Fix relocation
1627   RelocIterator iter(this);
1628   CodeBuffer src(&nm);
1629   CodeBuffer dst(this);
1630   while (iter.next()) {
1631 #ifdef USE_TRAMPOLINE_STUB_FIX_OWNER
1632     // After an nmethod is moved, some direct call sites may end up out of range.
1633     // CallRelocation::fix_relocation_after_move() assumes the target is always
1634     // reachable and does not check branch range. Calling it without range checks
1635     // could cause us to write an offset too large for the instruction.
1636     //
1637     // If a call site has a trampoline, we skip the normal call relocation. The
1638     // associated trampoline_stub_Relocation will handle the call and the
1639     // trampoline, including range checks and updating the branch as needed.
1640     //
1641     // If no trampoline exists, we can assume the call target is always
1642     // reachable and therefore within direct branch range, so calling
1643     // CallRelocation::fix_relocation_after_move() is safe.
1644     if (iter.reloc()->is_call()) {
1645       address trampoline = trampoline_stub_Relocation::get_trampoline_for(iter.reloc()->addr(), this);
1646       if (trampoline != nullptr) {
1647         continue;
1648       }
1649     }
1650 #endif
1651 
1652     iter.reloc()->fix_relocation_after_move(&src, &dst);
1653   }
1654 
1655   {
1656     MutexLocker ml(NMethodState_lock, Mutex::_no_safepoint_check_flag);
1657     clear_inline_caches();
1658   }
1659 
1660   post_init();
1661 }
1662 
1663 nmethod* nmethod::relocate(CodeBlobType code_blob_type) {
1664   assert(NMethodRelocation, "must enable use of function");
1665 
1666   // Locks required to be held by caller to ensure the nmethod
1667   // is not modified or purged from code cache during relocation
1668   assert_lock_strong(CodeCache_lock);
1669   assert_lock_strong(Compile_lock);
1670   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1671 
1672   if (!is_relocatable()) {
1673     return nullptr;
1674   }
1675 
1676   run_nmethod_entry_barrier();
1677   nmethod* nm_copy = new (size(), code_blob_type) nmethod(*this);
1678 
1679   if (nm_copy == nullptr) {
1680     return nullptr;
1681   }
1682 
1683   // To make dependency checking during class loading fast, record
1684   // the nmethod dependencies in the classes it is dependent on.
1685   // This allows the dependency checking code to simply walk the
1686   // class hierarchy above the loaded class, checking only nmethods
1687   // which are dependent on those classes.  The slow way is to
1688   // check every nmethod for dependencies which makes it linear in
1689   // the number of methods compiled.  For applications with a lot
1690   // classes the slow way is too slow.
1691   for (Dependencies::DepStream deps(nm_copy); deps.next(); ) {
1692     if (deps.type() == Dependencies::call_site_target_value) {
1693       // CallSite dependencies are managed on per-CallSite instance basis.
1694       oop call_site = deps.argument_oop(0);
1695       MethodHandles::add_dependent_nmethod(call_site, nm_copy);
1696     } else {
1697       InstanceKlass* ik = deps.context_type();
1698       if (ik == nullptr) {
1699         continue;  // ignore things like evol_method
1700       }
1701       // record this nmethod as dependent on this klass
1702       ik->add_dependent_nmethod(nm_copy);
1703     }
1704   }
1705 
1706   MutexLocker ml_NMethodState_lock(NMethodState_lock, Mutex::_no_safepoint_check_flag);
1707 
1708   // Verify the nm we copied from is still valid
1709   if (!is_marked_for_deoptimization() && is_in_use()) {
1710     assert(method() != nullptr && method()->code() == this, "should be if is in use");
1711 
1712     // Attempt to start using the copy
1713     if (nm_copy->make_in_use()) {
1714       ICache::invalidate_range(nm_copy->code_begin(), nm_copy->code_size());
1715 
1716       methodHandle mh(Thread::current(), nm_copy->method());
1717       nm_copy->method()->set_code(mh, nm_copy);
1718 
1719       make_not_entrant(InvalidationReason::RELOCATED);
1720 
1721       nm_copy->post_compiled_method_load_event();
1722 
1723       nm_copy->log_relocated_nmethod(this);
1724 
1725       return nm_copy;
1726     }
1727   }
1728 
1729   nm_copy->make_not_used();
1730 
1731   return nullptr;
1732 }
1733 
1734 bool nmethod::is_relocatable() {
1735   if (!is_java_method()) {
1736     return false;
1737   }
1738 
1739   if (!is_in_use()) {
1740     return false;
1741   }
1742 
1743   if (is_osr_method()) {
1744     return false;
1745   }
1746 
1747   if (is_marked_for_deoptimization()) {
1748     return false;
1749   }
1750 
1751 #if INCLUDE_JVMCI
1752   if (jvmci_nmethod_data() != nullptr && jvmci_nmethod_data()->has_mirror()) {
1753     return false;
1754   }
1755 #endif
1756 
1757   if (is_unloading()) {
1758     return false;
1759   }
1760 
1761   if (has_evol_metadata()) {
1762     return false;
1763   }
1764 
1765   return true;
1766 }
1767 
1768 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
1769   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
1770 }
1771 
1772 void* nmethod::operator new(size_t size, int nmethod_size, CodeBlobType code_blob_type) throw () {
1773   return CodeCache::allocate(nmethod_size, code_blob_type);
1774 }
1775 
1776 void* nmethod::operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw () {
1777   // Try MethodNonProfiled and MethodProfiled.
1778   void* return_value = CodeCache::allocate(nmethod_size, CodeBlobType::MethodNonProfiled);
1779   if (return_value != nullptr || !allow_NonNMethod_space) return return_value;
1780   // Try NonNMethod or give up.
1781   return CodeCache::allocate(nmethod_size, CodeBlobType::NonNMethod);
1782 }
1783 
1784 // For normal JIT compiled code
1785 nmethod::nmethod(
1786   Method* method,
1787   CompilerType type,
1788   int nmethod_size,
1789   int immutable_data_size,
1790   int mutable_data_size,
1791   int compile_id,
1792   int entry_bci,
1793   address immutable_data,
1794   CodeOffsets* offsets,
1795   int orig_pc_offset,
1796   DebugInformationRecorder* debug_info,
1797   Dependencies* dependencies,
1798   CodeBuffer *code_buffer,
1799   int frame_size,
1800   OopMapSet* oop_maps,
1801   ExceptionHandlerTable* handler_table,
1802   ImplicitExceptionTable* nul_chk_table,
1803   AbstractCompiler* compiler,
1804   CompLevel comp_level
1805 #if INCLUDE_JVMCI
1806   , char* speculations,
1807   int speculations_len,
1808   JVMCINMethodData* jvmci_data
1809 #endif
1810   )
1811   : CodeBlob("nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1812              offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, mutable_data_size),
1813   _deoptimization_generation(0),
1814   _gc_epoch(CodeCache::gc_epoch()),
1815   _method(method),
1816   _osr_link(nullptr)
1817 {
1818   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1819   {
1820     DEBUG_ONLY(NoSafepointVerifier nsv;)
1821     assert_locked_or_safepoint(CodeCache_lock);
1822 
1823     init_defaults(code_buffer, offsets);
1824     _method_profiling_count  = 0;
1825 
1826     _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
1827     _entry_bci       = entry_bci;
1828     _compile_id      = compile_id;
1829     _comp_level      = comp_level;
1830     _compiler_type   = type;
1831     _orig_pc_offset  = orig_pc_offset;
1832 
1833     _num_stack_arg_slots = entry_bci != InvocationEntryBci ? 0 : _method->constMethod()->num_stack_arg_slots();
1834 
1835     set_ctable_begin(header_begin() + content_offset());
1836 
1837 #if INCLUDE_JVMCI
1838     if (compiler->is_jvmci()) {
1839       // JVMCI might not produce any stub sections
1840       if (offsets->value(CodeOffsets::Exceptions) != -1) {
1841         _exception_offset        = code_offset() + offsets->value(CodeOffsets::Exceptions);
1842       } else {
1843         _exception_offset        = -1;
1844       }
1845       if (offsets->value(CodeOffsets::Deopt) != -1) {
1846         _deopt_handler_entry_offset    = code_offset() + offsets->value(CodeOffsets::Deopt);
1847       } else {
1848         _deopt_handler_entry_offset    = -1;
1849       }
1850     } else
1851 #endif
1852     {
1853       // Exception handler and deopt handler are in the stub section
1854       assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
1855 
1856       bool has_exception_handler = (offsets->value(CodeOffsets::Exceptions) != -1);
1857       assert(has_exception_handler == (compiler->type() != compiler_c2),
1858              "C2 compiler doesn't provide exception handler stub code.");
1859       if (has_exception_handler) {
1860         _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
1861       } else {
1862         _exception_offset = -1;
1863       }
1864 
1865       _deopt_handler_entry_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
1866     }
1867     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
1868       // C1 generates UnwindHandler at the end of instructions section.
1869       // Calculate positive offset as distance between the start of stubs section
1870       // (which is also the end of instructions section) and the start of the handler.
1871       int unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
1872       CHECKED_CAST(_unwind_handler_offset, int16_t, (_stub_offset - unwind_handler_offset));
1873     } else {
1874       _unwind_handler_offset = -1;
1875     }
1876 
1877     CHECKED_CAST(_oops_size, uint16_t, align_up(code_buffer->total_oop_size(), oopSize));
1878     uint16_t metadata_size;
1879     CHECKED_CAST(metadata_size, uint16_t, align_up(code_buffer->total_metadata_size(), wordSize));
1880     JVMCI_ONLY( _metadata_size = metadata_size; )
1881     int jvmci_data_size = 0 JVMCI_ONLY( + align_up(compiler->is_jvmci() ? jvmci_data->size() : 0, oopSize));
1882     assert(_mutable_data_size == _relocation_size + metadata_size + jvmci_data_size,
1883            "wrong mutable data size: %d != %d + %d + %d",
1884            _mutable_data_size, _relocation_size, metadata_size, jvmci_data_size);
1885     assert(nmethod_size == data_end() - header_begin(), "wrong nmethod size: %d != %d",
1886            nmethod_size, (int)(code_end() - header_begin()));
1887 
1888     _immutable_data_size  = immutable_data_size;
1889     if (immutable_data_size > 0) {
1890       assert(immutable_data != nullptr, "required");
1891       _immutable_data     = immutable_data;
1892     } else {
1893       // We need unique not null address
1894       _immutable_data     = blob_end();
1895     }
1896     CHECKED_CAST(_nul_chk_table_offset, uint16_t, (align_up((int)dependencies->size_in_bytes(), oopSize)));
1897     CHECKED_CAST(_handler_table_offset, uint16_t, (_nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize)));
1898     _scopes_pcs_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
1899     _scopes_data_offset   = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
1900 
1901 #if INCLUDE_JVMCI
1902     _speculations_offset  = _scopes_data_offset   + align_up(debug_info->data_size(), oopSize);
1903     _immutable_data_ref_count_offset = _speculations_offset + align_up(speculations_len, oopSize);
1904 #else
1905     _immutable_data_ref_count_offset = _scopes_data_offset + align_up(debug_info->data_size(), oopSize);
1906 #endif
1907     DEBUG_ONLY( int immutable_data_end_offset = _immutable_data_ref_count_offset + ImmutableDataRefCountSize; )
1908     assert(immutable_data_end_offset <= immutable_data_size, "wrong read-only data size: %d > %d",
1909            immutable_data_end_offset, immutable_data_size);
1910 
1911     // Copy code and relocation info
1912     code_buffer->copy_code_and_locs_to(this);
1913     // Copy oops and metadata
1914     code_buffer->copy_values_to(this);
1915     dependencies->copy_to(this);
1916     // Copy PcDesc and ScopeDesc data
1917     debug_info->copy_to(this);
1918 
1919     // Create cache after PcDesc data is copied - it will be used to initialize cache
1920     _pc_desc_container = new PcDescContainer(scopes_pcs_begin());
1921 
1922 #if INCLUDE_JVMCI
1923     if (compiler->is_jvmci()) {
1924       // Initialize the JVMCINMethodData object inlined into nm
1925       jvmci_nmethod_data()->copy(jvmci_data);
1926     }
1927 #endif
1928 
1929     // Copy contents of ExceptionHandlerTable to nmethod
1930     handler_table->copy_to(this);
1931     nul_chk_table->copy_to(this);
1932 
1933 #if INCLUDE_JVMCI
1934     // Copy speculations to nmethod
1935     if (speculations_size() != 0) {
1936       memcpy(speculations_begin(), speculations, speculations_len);
1937     }
1938 #endif
1939     init_immutable_data_ref_count();
1940 
1941     post_init();
1942 
1943     // we use the information of entry points to find out if a method is
1944     // static or non static
1945     assert(compiler->is_c2() || compiler->is_jvmci() ||
1946            _method->is_static() == (entry_point() == verified_entry_point()),
1947            " entry points must be same for static methods and vice versa");
1948   }
1949 }
1950 
1951 // Print a short set of xml attributes to identify this nmethod.  The
1952 // output should be embedded in some other element.
1953 void nmethod::log_identity(xmlStream* log) const {
1954   assert(log->inside_attrs_or_error(), "printing attributes");
1955   log->print(" compile_id='%d'", compile_id());
1956   const char* nm_kind = compile_kind();
1957   log->print(" compile_kind='%s'", nm_kind);
1958   log->print(" compiler='%s'", compiler_name());
1959   if (TieredCompilation) {
1960     log->print(" compile_level='%d'", comp_level());
1961   }
1962 #if INCLUDE_JVMCI
1963   if (jvmci_nmethod_data() != nullptr) {
1964     const char* jvmci_name = jvmci_nmethod_data()->name();
1965     if (jvmci_name != nullptr) {
1966       log->print(" jvmci_mirror_name='");
1967       log->text("%s", jvmci_name);
1968       log->print("'");
1969     }
1970   }
1971 #endif
1972 }
1973 
1974 
1975 #define LOG_OFFSET(log, name)                    \
1976   if (p2i(name##_end()) - p2i(name##_begin())) \
1977     log->print(" " XSTR(name) "_offset='%zd'"    , \
1978                p2i(name##_begin()) - p2i(this))
1979 
1980 
1981 void nmethod::log_new_nmethod() const {
1982   if (LogCompilation && xtty != nullptr) {
1983     ttyLocker ttyl;
1984     xtty->begin_elem("nmethod");
1985     log_identity(xtty);
1986     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
1987     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
1988 
1989     LOG_OFFSET(xtty, relocation);
1990     LOG_OFFSET(xtty, consts);
1991     LOG_OFFSET(xtty, insts);
1992     LOG_OFFSET(xtty, stub);
1993     LOG_OFFSET(xtty, scopes_data);
1994     LOG_OFFSET(xtty, scopes_pcs);
1995     LOG_OFFSET(xtty, dependencies);
1996     LOG_OFFSET(xtty, handler_table);
1997     LOG_OFFSET(xtty, nul_chk_table);
1998     LOG_OFFSET(xtty, oops);
1999     LOG_OFFSET(xtty, metadata);
2000 
2001     xtty->method(method());
2002     xtty->stamp();
2003     xtty->end_elem();
2004   }
2005 }
2006 
2007 
2008 void nmethod::log_relocated_nmethod(nmethod* original) const {
2009   if (LogCompilation && xtty != nullptr) {
2010     ttyLocker ttyl;
2011     xtty->begin_elem("relocated nmethod");
2012     log_identity(xtty);
2013     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
2014 
2015     const char* original_code_heap_name = CodeCache::get_code_heap_name(CodeCache::get_code_blob_type(original));
2016     xtty->print(" original_address='" INTPTR_FORMAT "'", p2i(original));
2017     xtty->print(" original_code_heap='%s'", original_code_heap_name);
2018 
2019     const char* new_code_heap_name = CodeCache::get_code_heap_name(CodeCache::get_code_blob_type(this));
2020     xtty->print(" new_address='" INTPTR_FORMAT "'", p2i(this));
2021     xtty->print(" new_code_heap='%s'", new_code_heap_name);
2022 
2023     LOG_OFFSET(xtty, relocation);
2024     LOG_OFFSET(xtty, consts);
2025     LOG_OFFSET(xtty, insts);
2026     LOG_OFFSET(xtty, stub);
2027     LOG_OFFSET(xtty, scopes_data);
2028     LOG_OFFSET(xtty, scopes_pcs);
2029     LOG_OFFSET(xtty, dependencies);
2030     LOG_OFFSET(xtty, handler_table);
2031     LOG_OFFSET(xtty, nul_chk_table);
2032     LOG_OFFSET(xtty, oops);
2033     LOG_OFFSET(xtty, metadata);
2034 
2035     xtty->method(method());
2036     xtty->stamp();
2037     xtty->end_elem();
2038   }
2039 }
2040 
2041 #undef LOG_OFFSET
2042 
2043 
2044 // Print out more verbose output usually for a newly created nmethod.
2045 void nmethod::print_on_with_msg(outputStream* st, const char* msg) const {
2046   if (st != nullptr) {
2047     ttyLocker ttyl;
2048     if (WizardMode) {
2049       CompileTask::print(st, this, msg, /*short_form:*/ true);
2050       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
2051     } else {
2052       CompileTask::print(st, this, msg, /*short_form:*/ false);
2053     }
2054   }
2055 }
2056 
2057 void nmethod::maybe_print_nmethod(const DirectiveSet* directive) {
2058   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
2059   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
2060     print_nmethod(printnmethods);
2061   }
2062 }
2063 
2064 void nmethod::print_nmethod(bool printmethod) {
2065   ttyLocker ttyl;  // keep the following output all in one block
2066   if (xtty != nullptr) {
2067     xtty->begin_head("print_nmethod");
2068     log_identity(xtty);
2069     xtty->stamp();
2070     xtty->end_head();
2071   }
2072   // Print the header part, then print the requested information.
2073   // This is both handled in decode2().
2074   if (printmethod) {
2075     ResourceMark m;
2076     if (is_compiled_by_c1()) {
2077       tty->cr();
2078       tty->print_cr("============================= C1-compiled nmethod ==============================");
2079     }
2080     if (is_compiled_by_jvmci()) {
2081       tty->cr();
2082       tty->print_cr("=========================== JVMCI-compiled nmethod =============================");
2083     }
2084     tty->print_cr("----------------------------------- Assembly -----------------------------------");
2085     decode2(tty);
2086 #if defined(SUPPORT_DATA_STRUCTS)
2087     if (AbstractDisassembler::show_structs()) {
2088       // Print the oops from the underlying CodeBlob as well.
2089       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2090       print_oops(tty);
2091       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2092       print_metadata(tty);
2093       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2094       print_pcs_on(tty);
2095       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2096       if (oop_maps() != nullptr) {
2097         tty->print("oop maps:"); // oop_maps()->print_on(tty) outputs a cr() at the beginning
2098         oop_maps()->print_on(tty);
2099         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2100       }
2101     }
2102 #endif
2103   } else {
2104     print(); // print the header part only.
2105   }
2106 
2107 #if defined(SUPPORT_DATA_STRUCTS)
2108   if (AbstractDisassembler::show_structs()) {
2109     methodHandle mh(Thread::current(), _method);
2110     if (printmethod || PrintDebugInfo || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDebugInfo)) {
2111       print_scopes();
2112       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2113     }
2114     if (printmethod || PrintRelocations || CompilerOracle::has_option(mh, CompileCommandEnum::PrintRelocations)) {
2115       print_relocations_on(tty);
2116       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2117     }
2118     if (printmethod || PrintDependencies || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDependencies)) {
2119       print_dependencies_on(tty);
2120       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2121     }
2122     if (printmethod || PrintExceptionHandlers) {
2123       print_handler_table();
2124       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2125       print_nul_chk_table();
2126       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2127     }
2128 
2129     if (printmethod) {
2130       print_recorded_oops();
2131       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2132       print_recorded_metadata();
2133       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2134     }
2135   }
2136 #endif
2137 
2138   if (xtty != nullptr) {
2139     xtty->tail("print_nmethod");
2140   }
2141 }
2142 
2143 
2144 // Promote one word from an assembly-time handle to a live embedded oop.
2145 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
2146   if (handle == nullptr ||
2147       // As a special case, IC oops are initialized to 1 or -1.
2148       handle == (jobject) Universe::non_oop_word()) {
2149     *(void**)dest = handle;
2150   } else {
2151     *dest = JNIHandles::resolve_non_null(handle);
2152   }
2153 }
2154 
2155 void nmethod::copy_values(GrowableArray<Handle>* array) {
2156   int length = array->length();
2157   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
2158   oop* dest = oops_begin();
2159   for (int index = 0 ; index < length; index++) {
2160     dest[index] = array->at(index)();
2161   }
2162 }
2163 
2164 // Have to have the same name because it's called by a template
2165 void nmethod::copy_values(GrowableArray<jobject>* array) {
2166   int length = array->length();
2167   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
2168   oop* dest = oops_begin();
2169   for (int index = 0 ; index < length; index++) {
2170     initialize_immediate_oop(&dest[index], array->at(index));
2171   }
2172 
2173   // Now we can fix up all the oops in the code.  We need to do this
2174   // in the code because the assembler uses jobjects as placeholders.
2175   // The code and relocations have already been initialized by the
2176   // CodeBlob constructor, so it is valid even at this early point to
2177   // iterate over relocations and patch the code.
2178   fix_oop_relocations(nullptr, nullptr, /*initialize_immediates=*/ true);
2179 }
2180 
2181 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
2182   int length = array->length();
2183   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
2184   Metadata** dest = metadata_begin();
2185   for (int index = 0 ; index < length; index++) {
2186     dest[index] = array->at(index);
2187   }
2188 }
2189 
2190 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
2191   // re-patch all oop-bearing instructions, just in case some oops moved
2192   RelocIterator iter(this, begin, end);
2193   while (iter.next()) {
2194     if (iter.type() == relocInfo::oop_type) {
2195       oop_Relocation* reloc = iter.oop_reloc();
2196       if (initialize_immediates && reloc->oop_is_immediate()) {
2197         oop* dest = reloc->oop_addr();
2198         jobject obj = *reinterpret_cast<jobject*>(dest);
2199         initialize_immediate_oop(dest, obj);
2200       }
2201       // Refresh the oop-related bits of this instruction.
2202       reloc->fix_oop_relocation();
2203     } else if (iter.type() == relocInfo::metadata_type) {
2204       metadata_Relocation* reloc = iter.metadata_reloc();
2205       reloc->fix_metadata_relocation();
2206     }
2207   }
2208 }
2209 
2210 void nmethod::create_reloc_immediates_list(JavaThread* thread, GrowableArray<Handle>& oop_list, GrowableArray<Metadata*>& metadata_list) {
2211   RelocIterator iter(this);
2212   while (iter.next()) {
2213     if (iter.type() == relocInfo::oop_type) {
2214       oop_Relocation* reloc = iter.oop_reloc();
2215       if (reloc->oop_is_immediate()) {
2216         oop dest = reloc->oop_value();
2217         Handle h(thread, dest);
2218         oop_list.append(h);
2219       }
2220     } else if (iter.type() == relocInfo::metadata_type) {
2221       metadata_Relocation* reloc = iter.metadata_reloc();
2222       if (reloc->metadata_is_immediate()) {
2223         Metadata* m = reloc->metadata_value();
2224         metadata_list.append(m);
2225       }
2226     }
2227   }
2228 }
2229 
2230 static void install_post_call_nop_displacement(nmethod* nm, address pc) {
2231   NativePostCallNop* nop = nativePostCallNop_at((address) pc);
2232   intptr_t cbaddr = (intptr_t) nm;
2233   intptr_t offset = ((intptr_t) pc) - cbaddr;
2234 
2235   int oopmap_slot = nm->oop_maps()->find_slot_for_offset(int((intptr_t) pc - (intptr_t) nm->code_begin()));
2236   if (oopmap_slot < 0) { // this can happen at asynchronous (non-safepoint) stackwalks
2237     log_debug(codecache)("failed to find oopmap for cb: " INTPTR_FORMAT " offset: %d", cbaddr, (int) offset);
2238   } else if (!nop->patch(oopmap_slot, offset)) {
2239     log_debug(codecache)("failed to encode %d %d", oopmap_slot, (int) offset);
2240   }
2241 }
2242 
2243 void nmethod::finalize_relocations() {
2244   NoSafepointVerifier nsv;
2245 
2246   GrowableArray<NativeMovConstReg*> virtual_call_data;
2247 
2248   // Make sure that post call nops fill in nmethod offsets eagerly so
2249   // we don't have to race with deoptimization
2250   RelocIterator iter(this);
2251   while (iter.next()) {
2252     if (iter.type() == relocInfo::virtual_call_type) {
2253       virtual_call_Relocation* r = iter.virtual_call_reloc();
2254       NativeMovConstReg* value = nativeMovConstReg_at(r->cached_value());
2255       virtual_call_data.append(value);
2256     } else if (iter.type() == relocInfo::post_call_nop_type) {
2257       post_call_nop_Relocation* const reloc = iter.post_call_nop_reloc();
2258       address pc = reloc->addr();
2259       install_post_call_nop_displacement(this, pc);
2260     }
2261   }
2262 
2263   if (virtual_call_data.length() > 0) {
2264     // We allocate a block of CompiledICData per nmethod so the GC can purge this faster.
2265     _compiled_ic_data = new CompiledICData[virtual_call_data.length()];
2266     CompiledICData* next_data = _compiled_ic_data;
2267 
2268     for (NativeMovConstReg* value : virtual_call_data) {
2269       value->set_data((intptr_t)next_data);
2270       next_data++;
2271     }
2272   }
2273 }
2274 
2275 void nmethod::make_deoptimized() {
2276   if (!Continuations::enabled()) {
2277     // Don't deopt this again.
2278     set_deoptimized_done();
2279     return;
2280   }
2281 
2282   assert(method() == nullptr || can_be_deoptimized(), "");
2283 
2284   CompiledICLocker ml(this);
2285   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
2286 
2287   // If post call nops have been already patched, we can just bail-out.
2288   if (has_been_deoptimized()) {
2289     return;
2290   }
2291 
2292   ResourceMark rm;
2293   RelocIterator iter(this, oops_reloc_begin());
2294 
2295   // Assume there will be some calls to make deoptimized.
2296   MACOS_AARCH64_ONLY(os::thread_wx_enable_write());
2297 
2298   while (iter.next()) {
2299 
2300     switch (iter.type()) {
2301       case relocInfo::virtual_call_type: {
2302         CompiledIC *ic = CompiledIC_at(&iter);
2303         address pc = ic->end_of_call();
2304         NativePostCallNop* nop = nativePostCallNop_at(pc);
2305         if (nop != nullptr) {
2306           nop->make_deopt();
2307         }
2308         assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
2309         break;
2310       }
2311       case relocInfo::static_call_type:
2312       case relocInfo::opt_virtual_call_type: {
2313         CompiledDirectCall *csc = CompiledDirectCall::at(iter.reloc());
2314         address pc = csc->end_of_call();
2315         NativePostCallNop* nop = nativePostCallNop_at(pc);
2316         //tty->print_cr(" - static pc %p", pc);
2317         if (nop != nullptr) {
2318           nop->make_deopt();
2319         }
2320         // We can't assert here, there are some calls to stubs / runtime
2321         // that have reloc data and doesn't have a post call NOP.
2322         //assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
2323         break;
2324       }
2325       default:
2326         break;
2327     }
2328   }
2329   // Don't deopt this again.
2330   set_deoptimized_done();
2331 }
2332 
2333 void nmethod::verify_clean_inline_caches() {
2334   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
2335 
2336   ResourceMark rm;
2337   RelocIterator iter(this, oops_reloc_begin());
2338   while(iter.next()) {
2339     switch(iter.type()) {
2340       case relocInfo::virtual_call_type: {
2341         CompiledIC *ic = CompiledIC_at(&iter);
2342         CodeBlob *cb = CodeCache::find_blob(ic->destination());
2343         assert(cb != nullptr, "destination not in CodeBlob?");
2344         nmethod* nm = cb->as_nmethod_or_null();
2345         if (nm != nullptr) {
2346           // Verify that inline caches pointing to bad nmethods are clean
2347           if (!nm->is_in_use() || nm->is_unloading()) {
2348             assert(ic->is_clean(), "IC should be clean");
2349           }
2350         }
2351         break;
2352       }
2353       case relocInfo::static_call_type:
2354       case relocInfo::opt_virtual_call_type: {
2355         CompiledDirectCall *cdc = CompiledDirectCall::at(iter.reloc());
2356         CodeBlob *cb = CodeCache::find_blob(cdc->destination());
2357         assert(cb != nullptr, "destination not in CodeBlob?");
2358         nmethod* nm = cb->as_nmethod_or_null();
2359         if (nm != nullptr) {
2360           // Verify that inline caches pointing to bad nmethods are clean
2361           if (!nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
2362             assert(cdc->is_clean(), "IC should be clean");
2363           }
2364         }
2365         break;
2366       }
2367       default:
2368         break;
2369     }
2370   }
2371 }
2372 
2373 void nmethod::mark_as_maybe_on_stack() {
2374   MACOS_AARCH64_ONLY(os::thread_wx_enable_write());
2375   AtomicAccess::store(&_gc_epoch, CodeCache::gc_epoch());
2376 }
2377 
2378 bool nmethod::is_maybe_on_stack() {
2379   // If the condition below is true, it means that the nmethod was found to
2380   // be alive the previous completed marking cycle.
2381   return AtomicAccess::load(&_gc_epoch) >= CodeCache::previous_completed_gc_marking_cycle();
2382 }
2383 
2384 void nmethod::inc_decompile_count() {
2385   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
2386   // Could be gated by ProfileTraps, but do not bother...
2387 #if INCLUDE_JVMCI
2388   if (jvmci_skip_profile_deopt()) {
2389     return;
2390   }
2391 #endif
2392   Method* m = method();
2393   if (m == nullptr)  return;
2394   MethodData* mdo = m->method_data();
2395   if (mdo == nullptr)  return;
2396   // There is a benign race here.  See comments in methodData.hpp.
2397   mdo->inc_decompile_count();
2398 }
2399 
2400 void nmethod::inc_method_profiling_count() {
2401   AtomicAccess::inc(&_method_profiling_count);
2402 }
2403 
2404 uint64_t nmethod::method_profiling_count() {
2405   return _method_profiling_count;
2406 }
2407 
2408 bool nmethod::try_transition(signed char new_state_int) {
2409   signed char new_state = new_state_int;
2410   assert_lock_strong(NMethodState_lock);
2411   signed char old_state = _state;
2412   if (old_state >= new_state) {
2413     // Ensure monotonicity of transitions.
2414     return false;
2415   }
2416   AtomicAccess::store(&_state, new_state);
2417   return true;
2418 }
2419 
2420 void nmethod::invalidate_osr_method() {
2421   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
2422   // Remove from list of active nmethods
2423   if (method() != nullptr) {
2424     method()->method_holder()->remove_osr_nmethod(this);
2425   }
2426 }
2427 
2428 void nmethod::log_state_change(InvalidationReason invalidation_reason) const {
2429   if (LogCompilation) {
2430     if (xtty != nullptr) {
2431       ttyLocker ttyl;  // keep the following output all in one block
2432       xtty->begin_elem("make_not_entrant thread='%zu' reason='%s'",
2433                        os::current_thread_id(), invalidation_reason_to_string(invalidation_reason));
2434       log_identity(xtty);
2435       xtty->stamp();
2436       xtty->end_elem();
2437     }
2438   }
2439 
2440   ResourceMark rm;
2441   stringStream ss(NEW_RESOURCE_ARRAY(char, 256), 256);
2442   ss.print("made not entrant: %s", invalidation_reason_to_string(invalidation_reason));
2443 
2444   CompileTask::print_ul(this, ss.freeze());
2445   if (PrintCompilation) {
2446     print_on_with_msg(tty, ss.freeze());
2447   }
2448 }
2449 
2450 void nmethod::unlink_from_method() {
2451   if (method() != nullptr) {
2452     method()->unlink_code(this);
2453   }
2454 }
2455 
2456 // Invalidate code
2457 bool nmethod::make_not_entrant(InvalidationReason invalidation_reason, bool keep_aot_entry) {
2458   // This can be called while the system is already at a safepoint which is ok
2459   NoSafepointVerifier nsv;
2460 
2461   if (is_unloading()) {
2462     // If the nmethod is unloading, then it is already not entrant through
2463     // the nmethod entry barriers. No need to do anything; GC will unload it.
2464     return false;
2465   }
2466 
2467   if (AtomicAccess::load(&_state) == not_entrant) {
2468     // Avoid taking the lock if already in required state.
2469     // This is safe from races because the state is an end-state,
2470     // which the nmethod cannot back out of once entered.
2471     // No need for fencing either.
2472     return false;
2473   }
2474 
2475   MACOS_AARCH64_ONLY(os::thread_wx_enable_write());
2476 
2477   {
2478     // Enter critical section.  Does not block for safepoint.
2479     ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
2480 
2481     if (AtomicAccess::load(&_state) == not_entrant) {
2482       // another thread already performed this transition so nothing
2483       // to do, but return false to indicate this.
2484       return false;
2485     }
2486 
2487     if (is_osr_method()) {
2488       // This logic is equivalent to the logic below for patching the
2489       // verified entry point of regular methods.
2490       // this effectively makes the osr nmethod not entrant
2491       invalidate_osr_method();
2492     } else {
2493       // The caller can be calling the method statically or through an inline
2494       // cache call.
2495       BarrierSet::barrier_set()->barrier_set_nmethod()->make_not_entrant(this);
2496     }
2497 
2498     if (update_recompile_counts()) {
2499       // Mark the method as decompiled.
2500       inc_decompile_count();
2501     }
2502 
2503     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2504     if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2505       // If nmethod entry barriers are not supported, we won't mark
2506       // nmethods as on-stack when they become on-stack. So we
2507       // degrade to a less accurate flushing strategy, for now.
2508       mark_as_maybe_on_stack();
2509     }
2510 
2511     // Change state
2512     bool success = try_transition(not_entrant);
2513     assert(success, "Transition can't fail");
2514 
2515     // Log the transition once
2516     log_state_change(invalidation_reason);
2517 
2518     // Remove nmethod from method.
2519     unlink_from_method();
2520 
2521     if (!keep_aot_entry) {
2522       // Keep AOT code if it was simply replaced
2523       // otherwise make it not entrant too.
2524       AOTCodeCache::invalidate(_aot_code_entry);
2525     }
2526 
2527     CompileBroker::log_not_entrant(this);
2528   } // leave critical region under NMethodState_lock
2529 
2530 #if INCLUDE_JVMCI
2531   // Invalidate can't occur while holding the NMethodState_lock
2532   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2533   if (nmethod_data != nullptr) {
2534     nmethod_data->invalidate_nmethod_mirror(this, invalidation_reason);
2535   }
2536 #endif
2537 
2538 #ifdef ASSERT
2539   if (is_osr_method() && method() != nullptr) {
2540     // Make sure osr nmethod is invalidated, i.e. not on the list
2541     bool found = method()->method_holder()->remove_osr_nmethod(this);
2542     assert(!found, "osr nmethod should have been invalidated");
2543   }
2544 #endif
2545 
2546   return true;
2547 }
2548 
2549 // For concurrent GCs, there must be a handshake between unlink and flush
2550 void nmethod::unlink() {
2551   if (is_unlinked()) {
2552     // Already unlinked.
2553     return;
2554   }
2555 
2556   flush_dependencies();
2557 
2558   // unlink_from_method will take the NMethodState_lock.
2559   // In this case we don't strictly need it when unlinking nmethods from
2560   // the Method, because it is only concurrently unlinked by
2561   // the entry barrier, which acquires the per nmethod lock.
2562   unlink_from_method();
2563 
2564   if (is_osr_method()) {
2565     invalidate_osr_method();
2566   }
2567 
2568 #if INCLUDE_JVMCI
2569   // Clear the link between this nmethod and a HotSpotNmethod mirror
2570   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2571   if (nmethod_data != nullptr) {
2572     nmethod_data->invalidate_nmethod_mirror(this, is_cold() ?
2573             nmethod::InvalidationReason::UNLOADING_COLD :
2574             nmethod::InvalidationReason::UNLOADING);
2575   }
2576 #endif
2577 
2578   // Post before flushing as jmethodID is being used
2579   post_compiled_method_unload();
2580 
2581   // Register for flushing when it is safe. For concurrent class unloading,
2582   // that would be after the unloading handshake, and for STW class unloading
2583   // that would be when getting back to the VM thread.
2584   ClassUnloadingContext::context()->register_unlinked_nmethod(this);
2585 }
2586 
2587 void nmethod::purge(bool unregister_nmethod) {
2588 
2589   MutexLocker ml(CodeCache_lock, Mutex::_no_safepoint_check_flag);
2590 
2591   // completely deallocate this method
2592   Events::log_nmethod_flush(Thread::current(), "flushing %s nmethod " INTPTR_FORMAT, compile_kind(), p2i(this));
2593 
2594   LogTarget(Debug, codecache) lt;
2595   if (lt.is_enabled()) {
2596     ResourceMark rm;
2597     LogStream ls(lt);
2598     const char* method_name = method()->name()->as_C_string();
2599     const size_t codecache_capacity = CodeCache::capacity()/1024;
2600     const size_t codecache_free_space = CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024;
2601     ls.print("Flushing %s nmethod %6d/" INTPTR_FORMAT ", level=%d, cold=%d, epoch=" UINT64_FORMAT ", cold_count=" UINT64_FORMAT ". "
2602               "Cache capacity: %zuKb, free space: %zuKb. method %s (%s)",
2603               compile_kind(), _compile_id, p2i(this), _comp_level, is_cold(), _gc_epoch, CodeCache::cold_gc_count(),
2604               codecache_capacity, codecache_free_space, method_name, compiler_name());
2605   }
2606 
2607   // We need to deallocate any ExceptionCache data.
2608   // Note that we do not need to grab the nmethod lock for this, it
2609   // better be thread safe if we're disposing of it!
2610   ExceptionCache* ec = exception_cache();
2611   while(ec != nullptr) {
2612     ExceptionCache* next = ec->next();
2613     delete ec;
2614     ec = next;
2615   }
2616   if (_pc_desc_container != nullptr) {
2617     delete _pc_desc_container;
2618   }
2619   if (_compiled_ic_data != nullptr) {
2620     delete[] _compiled_ic_data;
2621   }
2622 
2623   if (_immutable_data != blob_end() && !AOTCodeCache::is_address_in_aot_cache((address)_oop_maps)) {
2624     // Free memory if this was the last nmethod referencing immutable data
2625     if (dec_immutable_data_ref_count() == 0) {
2626       os::free(_immutable_data);
2627     }
2628 
2629     _immutable_data = blob_end(); // Valid not null address
2630   }
2631 
2632   if (unregister_nmethod) {
2633     Universe::heap()->unregister_nmethod(this);
2634   }
2635   CodeCache::unregister_old_nmethod(this);
2636 
2637   JVMCI_ONLY( _metadata_size = 0; )
2638   CodeBlob::purge();
2639 }
2640 
2641 oop nmethod::oop_at(int index) const {
2642   if (index == 0) {
2643     return nullptr;
2644   }
2645 
2646   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2647   return bs_nm->oop_load_no_keepalive(this, index);
2648 }
2649 
2650 oop nmethod::oop_at_phantom(int index) const {
2651   if (index == 0) {
2652     return nullptr;
2653   }
2654 
2655   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2656   return bs_nm->oop_load_phantom(this, index);
2657 }
2658 
2659 //
2660 // Notify all classes this nmethod is dependent on that it is no
2661 // longer dependent.
2662 
2663 void nmethod::flush_dependencies() {
2664   if (!has_flushed_dependencies()) {
2665     set_has_flushed_dependencies(true);
2666     for (Dependencies::DepStream deps(this); deps.next(); ) {
2667       if (deps.type() == Dependencies::call_site_target_value) {
2668         // CallSite dependencies are managed on per-CallSite instance basis.
2669         oop call_site = deps.argument_oop(0);
2670         MethodHandles::clean_dependency_context(call_site);
2671       } else {
2672         InstanceKlass* ik = deps.context_type();
2673         if (ik == nullptr) {
2674           continue;  // ignore things like evol_method
2675         }
2676         // During GC liveness of dependee determines class that needs to be updated.
2677         // The GC may clean dependency contexts concurrently and in parallel.
2678         ik->clean_dependency_context();
2679       }
2680     }
2681   }
2682 }
2683 
2684 void nmethod::post_compiled_method(CompileTask* task) {
2685   task->mark_success();
2686   task->set_nm_content_size(content_size());
2687   task->set_nm_insts_size(insts_size());
2688   task->set_nm_total_size(total_size());
2689 
2690   CompileTrainingData* ctd = task->training_data();
2691   if (ctd != nullptr) {
2692     // Record inline code size during training to help inlining during production run
2693     precond(TrainingData::need_data()); // training run
2694     int inline_size = inline_instructions_size();
2695     if (inline_size < 0) inline_size = 0;
2696     ctd->set_inline_instructions_size(inline_size);
2697   }
2698 
2699   // task->is_aot_load() is true only for loaded AOT code.
2700   // nmethod::_aot_code_entry is set for loaded and stored AOT code
2701   // to invalidate the entry when nmethod is deoptimized.
2702   // VerifyAOTCode is option to not store in archive AOT code.
2703   guarantee((_aot_code_entry != nullptr) || !task->is_aot_load() || VerifyAOTCode, "sanity");
2704 
2705   // JVMTI -- compiled method notification (must be done outside lock)
2706   post_compiled_method_load_event();
2707 
2708   if (CompilationLog::log() != nullptr) {
2709     CompilationLog::log()->log_nmethod(JavaThread::current(), this);
2710   }
2711 
2712   const DirectiveSet* directive = task->directive();
2713   maybe_print_nmethod(directive);
2714 }
2715 
2716 #if INCLUDE_CDS
2717 static GrowableArrayCHeap<nmethod*, mtClassShared>* _delayed_compiled_method_load_events = nullptr;
2718 
2719 void nmethod::add_delayed_compiled_method_load_event(nmethod* nm) {
2720   precond(CDSConfig::is_using_aot_linked_classes());
2721   precond(!ServiceThread::has_started());
2722 
2723   // We are still in single threaded stage of VM bootstrap. No need to lock.
2724   if (_delayed_compiled_method_load_events == nullptr) {
2725     _delayed_compiled_method_load_events = new GrowableArrayCHeap<nmethod*, mtClassShared>();
2726   }
2727   _delayed_compiled_method_load_events->append(nm);
2728 }
2729 
2730 void nmethod::post_delayed_compiled_method_load_events() {
2731   precond(ServiceThread::has_started());
2732   if (_delayed_compiled_method_load_events != nullptr) {
2733     for (int i = 0; i < _delayed_compiled_method_load_events->length(); i++) {
2734       nmethod* nm = _delayed_compiled_method_load_events->at(i);
2735       nm->post_compiled_method_load_event();
2736     }
2737     delete _delayed_compiled_method_load_events;
2738     _delayed_compiled_method_load_events = nullptr;
2739   }
2740 }
2741 #endif
2742 
2743 // ------------------------------------------------------------------
2744 // post_compiled_method_load_event
2745 // new method for install_code() path
2746 // Transfer information from compilation to jvmti
2747 void nmethod::post_compiled_method_load_event(JvmtiThreadState* state) {
2748 #if INCLUDE_CDS
2749   if (!ServiceThread::has_started()) {
2750     // With AOT-linked classes, we could compile wrappers for native methods before the
2751     // ServiceThread has been started, so we must delay the events to be posted later.
2752     assert(state == nullptr, "must be");
2753     add_delayed_compiled_method_load_event(this);
2754     return;
2755   }
2756 #endif
2757 
2758   // This is a bad time for a safepoint.  We don't want
2759   // this nmethod to get unloaded while we're queueing the event.
2760   NoSafepointVerifier nsv;
2761 
2762   Method* m = method();
2763   HOTSPOT_COMPILED_METHOD_LOAD(
2764       (char *) m->klass_name()->bytes(),
2765       m->klass_name()->utf8_length(),
2766       (char *) m->name()->bytes(),
2767       m->name()->utf8_length(),
2768       (char *) m->signature()->bytes(),
2769       m->signature()->utf8_length(),
2770       insts_begin(), insts_size());
2771 
2772 
2773   if (JvmtiExport::should_post_compiled_method_load()) {
2774     // Only post unload events if load events are found.
2775     set_load_reported();
2776     // If a JavaThread hasn't been passed in, let the Service thread
2777     // (which is a real Java thread) post the event
2778     JvmtiDeferredEvent event = JvmtiDeferredEvent::compiled_method_load_event(this);
2779     if (state == nullptr) {
2780       // Execute any barrier code for this nmethod as if it's called, since
2781       // keeping it alive looks like stack walking.
2782       run_nmethod_entry_barrier();
2783       ServiceThread::enqueue_deferred_event(&event);
2784     } else {
2785       // This enters the nmethod barrier outside in the caller.
2786       state->enqueue_event(&event);
2787     }
2788   }
2789 }
2790 
2791 void nmethod::post_compiled_method_unload() {
2792   assert(_method != nullptr, "just checking");
2793   DTRACE_METHOD_UNLOAD_PROBE(method());
2794 
2795   // If a JVMTI agent has enabled the CompiledMethodUnload event then
2796   // post the event. The Method* will not be valid when this is freed.
2797 
2798   // Don't bother posting the unload if the load event wasn't posted.
2799   if (load_reported() && JvmtiExport::should_post_compiled_method_unload()) {
2800     JvmtiDeferredEvent event =
2801       JvmtiDeferredEvent::compiled_method_unload_event(
2802           method()->jmethod_id(), insts_begin());
2803     ServiceThread::enqueue_deferred_event(&event);
2804   }
2805 }
2806 
2807 // Iterate over metadata calling this function.   Used by RedefineClasses
2808 void nmethod::metadata_do(MetadataClosure* f) {
2809   {
2810     // Visit all immediate references that are embedded in the instruction stream.
2811     RelocIterator iter(this, oops_reloc_begin());
2812     while (iter.next()) {
2813       if (iter.type() == relocInfo::metadata_type) {
2814         metadata_Relocation* r = iter.metadata_reloc();
2815         // In this metadata, we must only follow those metadatas directly embedded in
2816         // the code.  Other metadatas (oop_index>0) are seen as part of
2817         // the metadata section below.
2818         assert(1 == (r->metadata_is_immediate()) +
2819                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2820                "metadata must be found in exactly one place");
2821         if (r->metadata_is_immediate() && r->metadata_value() != nullptr) {
2822           Metadata* md = r->metadata_value();
2823           if (md != _method) f->do_metadata(md);
2824         }
2825       } else if (iter.type() == relocInfo::virtual_call_type) {
2826         // Check compiledIC holders associated with this nmethod
2827         ResourceMark rm;
2828         CompiledIC *ic = CompiledIC_at(&iter);
2829         ic->metadata_do(f);
2830       }
2831     }
2832   }
2833 
2834   // Visit the metadata section
2835   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2836     if (*p == Universe::non_oop_word() || *p == nullptr)  continue;  // skip non-oops
2837     Metadata* md = *p;
2838     f->do_metadata(md);
2839   }
2840 
2841   // Visit metadata not embedded in the other places.
2842   if (_method != nullptr) f->do_metadata(_method);
2843 }
2844 
2845 // Heuristic for nuking nmethods even though their oops are live.
2846 // Main purpose is to reduce code cache pressure and get rid of
2847 // nmethods that don't seem to be all that relevant any longer.
2848 bool nmethod::is_cold() {
2849   if (!MethodFlushing || is_not_installed()) {
2850     // No heuristic unloading at all
2851     return false;
2852   }
2853 
2854   if (!is_maybe_on_stack() && is_not_entrant()) {
2855     // Not entrant nmethods that are not on any stack can just
2856     // be removed
2857     return true;
2858   }
2859 
2860   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2861   if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2862     // On platforms that don't support nmethod entry barriers, we can't
2863     // trust the temporal aspect of the gc epochs. So we can't detect
2864     // cold nmethods on such platforms.
2865     return false;
2866   }
2867 
2868   if (!UseCodeCacheFlushing) {
2869     // Bail out if we don't heuristically remove nmethods
2870     return false;
2871   }
2872 
2873   // Other code can be phased out more gradually after N GCs
2874   return CodeCache::previous_completed_gc_marking_cycle() > _gc_epoch + 2 * CodeCache::cold_gc_count();
2875 }
2876 
2877 // The _is_unloading_state encodes a tuple comprising the unloading cycle
2878 // and the result of IsUnloadingBehaviour::is_unloading() for that cycle.
2879 // This is the bit layout of the _is_unloading_state byte: 00000CCU
2880 // CC refers to the cycle, which has 2 bits, and U refers to the result of
2881 // IsUnloadingBehaviour::is_unloading() for that unloading cycle.
2882 
2883 class IsUnloadingState: public AllStatic {
2884   static const uint8_t _is_unloading_mask = 1;
2885   static const uint8_t _is_unloading_shift = 0;
2886   static const uint8_t _unloading_cycle_mask = 6;
2887   static const uint8_t _unloading_cycle_shift = 1;
2888 
2889   static uint8_t set_is_unloading(uint8_t state, bool value) {
2890     state &= (uint8_t)~_is_unloading_mask;
2891     if (value) {
2892       state |= 1 << _is_unloading_shift;
2893     }
2894     assert(is_unloading(state) == value, "unexpected unloading cycle overflow");
2895     return state;
2896   }
2897 
2898   static uint8_t set_unloading_cycle(uint8_t state, uint8_t value) {
2899     state &= (uint8_t)~_unloading_cycle_mask;
2900     state |= (uint8_t)(value << _unloading_cycle_shift);
2901     assert(unloading_cycle(state) == value, "unexpected unloading cycle overflow");
2902     return state;
2903   }
2904 
2905 public:
2906   static bool is_unloading(uint8_t state) { return (state & _is_unloading_mask) >> _is_unloading_shift == 1; }
2907   static uint8_t unloading_cycle(uint8_t state) { return (state & _unloading_cycle_mask) >> _unloading_cycle_shift; }
2908 
2909   static uint8_t create(bool is_unloading, uint8_t unloading_cycle) {
2910     uint8_t state = 0;
2911     state = set_is_unloading(state, is_unloading);
2912     state = set_unloading_cycle(state, unloading_cycle);
2913     return state;
2914   }
2915 };
2916 
2917 bool nmethod::is_unloading() {
2918   uint8_t state = AtomicAccess::load(&_is_unloading_state);
2919   bool state_is_unloading = IsUnloadingState::is_unloading(state);
2920   if (state_is_unloading) {
2921     return true;
2922   }
2923   uint8_t state_unloading_cycle = IsUnloadingState::unloading_cycle(state);
2924   uint8_t current_cycle = CodeCache::unloading_cycle();
2925   if (state_unloading_cycle == current_cycle) {
2926     return false;
2927   }
2928 
2929   // The IsUnloadingBehaviour is responsible for calculating if the nmethod
2930   // should be unloaded. This can be either because there is a dead oop,
2931   // or because is_cold() heuristically determines it is time to unload.
2932   state_unloading_cycle = current_cycle;
2933   state_is_unloading = IsUnloadingBehaviour::is_unloading(this);
2934   uint8_t new_state = IsUnloadingState::create(state_is_unloading, state_unloading_cycle);
2935 
2936   MACOS_AARCH64_ONLY(os::thread_wx_enable_write());
2937 
2938   // Note that if an nmethod has dead oops, everyone will agree that the
2939   // nmethod is_unloading. However, the is_cold heuristics can yield
2940   // different outcomes, so we guard the computed result with a CAS
2941   // to ensure all threads have a shared view of whether an nmethod
2942   // is_unloading or not.
2943   uint8_t found_state = AtomicAccess::cmpxchg(&_is_unloading_state, state, new_state, memory_order_relaxed);
2944 
2945   if (found_state == state) {
2946     // First to change state, we win
2947     return state_is_unloading;
2948   } else {
2949     // State already set, so use it
2950     return IsUnloadingState::is_unloading(found_state);
2951   }
2952 }
2953 
2954 void nmethod::clear_unloading_state() {
2955   uint8_t state = IsUnloadingState::create(false, CodeCache::unloading_cycle());
2956   AtomicAccess::store(&_is_unloading_state, state);
2957 }
2958 
2959 
2960 // This is called at the end of the strong tracing/marking phase of a
2961 // GC to unload an nmethod if it contains otherwise unreachable
2962 // oops or is heuristically found to be not important.
2963 void nmethod::do_unloading(bool unloading_occurred) {
2964   // Make sure the oop's ready to receive visitors
2965   if (is_unloading()) {
2966     unlink();
2967   } else {
2968     unload_nmethod_caches(unloading_occurred);
2969     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2970     if (bs_nm != nullptr) {
2971       bs_nm->disarm(this);
2972     }
2973   }
2974 }
2975 
2976 void nmethod::oops_do(OopClosure* f) {
2977   // Prevent extra code cache walk for platforms that don't have immediate oops.
2978   if (relocInfo::mustIterateImmediateOopsInCode()) {
2979     RelocIterator iter(this, oops_reloc_begin());
2980 
2981     while (iter.next()) {
2982       if (iter.type() == relocInfo::oop_type ) {
2983         oop_Relocation* r = iter.oop_reloc();
2984         // In this loop, we must only follow those oops directly embedded in
2985         // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
2986         assert(1 == (r->oop_is_immediate()) +
2987                (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2988                "oop must be found in exactly one place");
2989         if (r->oop_is_immediate() && r->oop_value() != nullptr) {
2990           f->do_oop(r->oop_addr());
2991         }
2992       }
2993     }
2994   }
2995 
2996   // Scopes
2997   // This includes oop constants not inlined in the code stream.
2998   for (oop* p = oops_begin(); p < oops_end(); p++) {
2999     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
3000     f->do_oop(p);
3001   }
3002 }
3003 
3004 void nmethod::follow_nmethod(OopIterateClosure* cl) {
3005   // Process oops in the nmethod
3006   oops_do(cl);
3007 
3008   // CodeCache unloading support
3009   mark_as_maybe_on_stack();
3010 
3011   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
3012   bs_nm->disarm(this);
3013 
3014   // There's an assumption made that this function is not used by GCs that
3015   // relocate objects, and therefore we don't call fix_oop_relocations.
3016 }
3017 
3018 nmethod* volatile nmethod::_oops_do_mark_nmethods;
3019 
3020 void nmethod::oops_do_log_change(const char* state) {
3021   LogTarget(Trace, gc, nmethod) lt;
3022   if (lt.is_enabled()) {
3023     LogStream ls(lt);
3024     CompileTask::print(&ls, this, state, true /* short_form */);
3025   }
3026 }
3027 
3028 bool nmethod::oops_do_try_claim() {
3029   if (oops_do_try_claim_weak_request()) {
3030     nmethod* result = oops_do_try_add_to_list_as_weak_done();
3031     assert(result == nullptr, "adding to global list as weak done must always succeed.");
3032     return true;
3033   }
3034   return false;
3035 }
3036 
3037 bool nmethod::oops_do_try_claim_weak_request() {
3038   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
3039 
3040   if ((_oops_do_mark_link == nullptr) &&
3041       (AtomicAccess::replace_if_null(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag)))) {
3042     oops_do_log_change("oops_do, mark weak request");
3043     return true;
3044   }
3045   return false;
3046 }
3047 
3048 void nmethod::oops_do_set_strong_done(nmethod* old_head) {
3049   _oops_do_mark_link = mark_link(old_head, claim_strong_done_tag);
3050 }
3051 
3052 nmethod::oops_do_mark_link* nmethod::oops_do_try_claim_strong_done() {
3053   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
3054 
3055   oops_do_mark_link* old_next = AtomicAccess::cmpxchg(&_oops_do_mark_link, mark_link(nullptr, claim_weak_request_tag), mark_link(this, claim_strong_done_tag));
3056   if (old_next == nullptr) {
3057     oops_do_log_change("oops_do, mark strong done");
3058   }
3059   return old_next;
3060 }
3061 
3062 nmethod::oops_do_mark_link* nmethod::oops_do_try_add_strong_request(nmethod::oops_do_mark_link* next) {
3063   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
3064   assert(next == mark_link(this, claim_weak_request_tag), "Should be claimed as weak");
3065 
3066   oops_do_mark_link* old_next = AtomicAccess::cmpxchg(&_oops_do_mark_link, next, mark_link(this, claim_strong_request_tag));
3067   if (old_next == next) {
3068     oops_do_log_change("oops_do, mark strong request");
3069   }
3070   return old_next;
3071 }
3072 
3073 bool nmethod::oops_do_try_claim_weak_done_as_strong_done(nmethod::oops_do_mark_link* next) {
3074   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
3075   assert(extract_state(next) == claim_weak_done_tag, "Should be claimed as weak done");
3076 
3077   oops_do_mark_link* old_next = AtomicAccess::cmpxchg(&_oops_do_mark_link, next, mark_link(extract_nmethod(next), claim_strong_done_tag));
3078   if (old_next == next) {
3079     oops_do_log_change("oops_do, mark weak done -> mark strong done");
3080     return true;
3081   }
3082   return false;
3083 }
3084 
3085 nmethod* nmethod::oops_do_try_add_to_list_as_weak_done() {
3086   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
3087 
3088   assert(extract_state(_oops_do_mark_link) == claim_weak_request_tag ||
3089          extract_state(_oops_do_mark_link) == claim_strong_request_tag,
3090          "must be but is nmethod " PTR_FORMAT " %u", p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
3091 
3092   nmethod* old_head = AtomicAccess::xchg(&_oops_do_mark_nmethods, this);
3093   // Self-loop if needed.
3094   if (old_head == nullptr) {
3095     old_head = this;
3096   }
3097   // Try to install end of list and weak done tag.
3098   if (AtomicAccess::cmpxchg(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag), mark_link(old_head, claim_weak_done_tag)) == mark_link(this, claim_weak_request_tag)) {
3099     oops_do_log_change("oops_do, mark weak done");
3100     return nullptr;
3101   } else {
3102     return old_head;
3103   }
3104 }
3105 
3106 void nmethod::oops_do_add_to_list_as_strong_done() {
3107   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
3108 
3109   nmethod* old_head = AtomicAccess::xchg(&_oops_do_mark_nmethods, this);
3110   // Self-loop if needed.
3111   if (old_head == nullptr) {
3112     old_head = this;
3113   }
3114   assert(_oops_do_mark_link == mark_link(this, claim_strong_done_tag), "must be but is nmethod " PTR_FORMAT " state %u",
3115          p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
3116 
3117   oops_do_set_strong_done(old_head);
3118 }
3119 
3120 void nmethod::oops_do_process_weak(OopsDoProcessor* p) {
3121   if (!oops_do_try_claim_weak_request()) {
3122     // Failed to claim for weak processing.
3123     oops_do_log_change("oops_do, mark weak request fail");
3124     return;
3125   }
3126 
3127   p->do_regular_processing(this);
3128 
3129   nmethod* old_head = oops_do_try_add_to_list_as_weak_done();
3130   if (old_head == nullptr) {
3131     return;
3132   }
3133   oops_do_log_change("oops_do, mark weak done fail");
3134   // Adding to global list failed, another thread added a strong request.
3135   assert(extract_state(_oops_do_mark_link) == claim_strong_request_tag,
3136          "must be but is %u", extract_state(_oops_do_mark_link));
3137 
3138   oops_do_log_change("oops_do, mark weak request -> mark strong done");
3139 
3140   oops_do_set_strong_done(old_head);
3141   // Do missing strong processing.
3142   p->do_remaining_strong_processing(this);
3143 }
3144 
3145 void nmethod::oops_do_process_strong(OopsDoProcessor* p) {
3146   oops_do_mark_link* next_raw = oops_do_try_claim_strong_done();
3147   if (next_raw == nullptr) {
3148     p->do_regular_processing(this);
3149     oops_do_add_to_list_as_strong_done();
3150     return;
3151   }
3152   // Claim failed. Figure out why and handle it.
3153   if (oops_do_has_weak_request(next_raw)) {
3154     oops_do_mark_link* old = next_raw;
3155     // Claim failed because being weak processed (state == "weak request").
3156     // Try to request deferred strong processing.
3157     next_raw = oops_do_try_add_strong_request(old);
3158     if (next_raw == old) {
3159       // Successfully requested deferred strong processing.
3160       return;
3161     }
3162     // Failed because of a concurrent transition. No longer in "weak request" state.
3163   }
3164   if (oops_do_has_any_strong_state(next_raw)) {
3165     // Already claimed for strong processing or requested for such.
3166     return;
3167   }
3168   if (oops_do_try_claim_weak_done_as_strong_done(next_raw)) {
3169     // Successfully claimed "weak done" as "strong done". Do the missing marking.
3170     p->do_remaining_strong_processing(this);
3171     return;
3172   }
3173   // Claim failed, some other thread got it.
3174 }
3175 
3176 void nmethod::oops_do_marking_prologue() {
3177   assert_at_safepoint();
3178 
3179   log_trace(gc, nmethod)("oops_do_marking_prologue");
3180   assert(_oops_do_mark_nmethods == nullptr, "must be empty");
3181 }
3182 
3183 void nmethod::oops_do_marking_epilogue() {
3184   assert_at_safepoint();
3185 
3186   nmethod* next = _oops_do_mark_nmethods;
3187   _oops_do_mark_nmethods = nullptr;
3188   if (next != nullptr) {
3189     nmethod* cur;
3190     do {
3191       cur = next;
3192       next = extract_nmethod(cur->_oops_do_mark_link);
3193       cur->_oops_do_mark_link = nullptr;
3194       DEBUG_ONLY(cur->verify_oop_relocations());
3195 
3196       LogTarget(Trace, gc, nmethod) lt;
3197       if (lt.is_enabled()) {
3198         LogStream ls(lt);
3199         CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
3200       }
3201       // End if self-loop has been detected.
3202     } while (cur != next);
3203   }
3204   log_trace(gc, nmethod)("oops_do_marking_epilogue");
3205 }
3206 
3207 inline bool includes(void* p, void* from, void* to) {
3208   return from <= p && p < to;
3209 }
3210 
3211 
3212 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
3213   assert(count >= 2, "must be sentinel values, at least");
3214 
3215 #ifdef ASSERT
3216   // must be sorted and unique; we do a binary search in find_pc_desc()
3217   int prev_offset = pcs[0].pc_offset();
3218   assert(prev_offset == PcDesc::lower_offset_limit,
3219          "must start with a sentinel");
3220   for (int i = 1; i < count; i++) {
3221     int this_offset = pcs[i].pc_offset();
3222     assert(this_offset > prev_offset, "offsets must be sorted");
3223     prev_offset = this_offset;
3224   }
3225   assert(prev_offset == PcDesc::upper_offset_limit,
3226          "must end with a sentinel");
3227 #endif //ASSERT
3228 
3229   int size = count * sizeof(PcDesc);
3230   assert(scopes_pcs_size() >= size, "oob");
3231   memcpy(scopes_pcs_begin(), pcs, size);
3232 
3233   // Adjust the final sentinel downward.
3234   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
3235   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
3236   last_pc->set_pc_offset(content_size() + 1);
3237   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
3238     // Fill any rounding gaps with copies of the last record.
3239     last_pc[1] = last_pc[0];
3240   }
3241   // The following assert could fail if sizeof(PcDesc) is not
3242   // an integral multiple of oopSize (the rounding term).
3243   // If it fails, change the logic to always allocate a multiple
3244   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
3245   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
3246 }
3247 
3248 void nmethod::copy_scopes_data(u_char* buffer, int size) {
3249   assert(scopes_data_size() >= size, "oob");
3250   memcpy(scopes_data_begin(), buffer, size);
3251 }
3252 
3253 #ifdef ASSERT
3254 static PcDesc* linear_search(int pc_offset, bool approximate, PcDesc* lower, PcDesc* upper) {
3255   PcDesc* res = nullptr;
3256   assert(lower != nullptr && lower->pc_offset() == PcDesc::lower_offset_limit,
3257          "must start with a sentinel");
3258   // lower + 1 to exclude initial sentinel
3259   for (PcDesc* p = lower + 1; p < upper; p++) {
3260     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
3261     if (match_desc(p, pc_offset, approximate)) {
3262       if (res == nullptr) {
3263         res = p;
3264       } else {
3265         res = (PcDesc*) badAddress;
3266       }
3267     }
3268   }
3269   return res;
3270 }
3271 #endif
3272 
3273 
3274 #ifndef PRODUCT
3275 // Version of method to collect statistic
3276 PcDesc* PcDescContainer::find_pc_desc(address pc, bool approximate, address code_begin,
3277                                       PcDesc* lower, PcDesc* upper) {
3278   ++pc_nmethod_stats.pc_desc_queries;
3279   if (approximate) ++pc_nmethod_stats.pc_desc_approx;
3280 
3281   PcDesc* desc = _pc_desc_cache.last_pc_desc();
3282   assert(desc != nullptr, "PcDesc cache should be initialized already");
3283   if (desc->pc_offset() == (pc - code_begin)) {
3284     // Cached value matched
3285     ++pc_nmethod_stats.pc_desc_tests;
3286     ++pc_nmethod_stats.pc_desc_repeats;
3287     return desc;
3288   }
3289   return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
3290 }
3291 #endif
3292 
3293 // Finds a PcDesc with real-pc equal to "pc"
3294 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, address code_begin,
3295                                                PcDesc* lower_incl, PcDesc* upper_incl) {
3296   if ((pc < code_begin) ||
3297       (pc - code_begin) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
3298     return nullptr;  // PC is wildly out of range
3299   }
3300   int pc_offset = (int) (pc - code_begin);
3301 
3302   // Check the PcDesc cache if it contains the desired PcDesc
3303   // (This as an almost 100% hit rate.)
3304   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
3305   if (res != nullptr) {
3306     assert(res == linear_search(pc_offset, approximate, lower_incl, upper_incl), "cache ok");
3307     return res;
3308   }
3309 
3310   // Fallback algorithm: quasi-linear search for the PcDesc
3311   // Find the last pc_offset less than the given offset.
3312   // The successor must be the required match, if there is a match at all.
3313   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
3314   PcDesc* lower = lower_incl;     // this is initial sentinel
3315   PcDesc* upper = upper_incl - 1; // exclude final sentinel
3316   if (lower >= upper)  return nullptr;  // no PcDescs at all
3317 
3318 #define assert_LU_OK \
3319   /* invariant on lower..upper during the following search: */ \
3320   assert(lower->pc_offset() <  pc_offset, "sanity"); \
3321   assert(upper->pc_offset() >= pc_offset, "sanity")
3322   assert_LU_OK;
3323 
3324   // Use the last successful return as a split point.
3325   PcDesc* mid = _pc_desc_cache.last_pc_desc();
3326   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
3327   if (mid->pc_offset() < pc_offset) {
3328     lower = mid;
3329   } else {
3330     upper = mid;
3331   }
3332 
3333   // Take giant steps at first (4096, then 256, then 16, then 1)
3334   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ DEBUG_ONLY(-1);
3335   const int RADIX = (1 << LOG2_RADIX);
3336   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
3337     while ((mid = lower + step) < upper) {
3338       assert_LU_OK;
3339       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
3340       if (mid->pc_offset() < pc_offset) {
3341         lower = mid;
3342       } else {
3343         upper = mid;
3344         break;
3345       }
3346     }
3347     assert_LU_OK;
3348   }
3349 
3350   // Sneak up on the value with a linear search of length ~16.
3351   while (true) {
3352     assert_LU_OK;
3353     mid = lower + 1;
3354     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
3355     if (mid->pc_offset() < pc_offset) {
3356       lower = mid;
3357     } else {
3358       upper = mid;
3359       break;
3360     }
3361   }
3362 #undef assert_LU_OK
3363 
3364   if (match_desc(upper, pc_offset, approximate)) {
3365     assert(upper == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
3366     if (!Thread::current_in_asgct()) {
3367       // we don't want to modify the cache if we're in ASGCT
3368       // which is typically called in a signal handler
3369       _pc_desc_cache.add_pc_desc(upper);
3370     }
3371     return upper;
3372   } else {
3373     assert(nullptr == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
3374     return nullptr;
3375   }
3376 }
3377 
3378 bool nmethod::check_dependency_on(DepChange& changes) {
3379   // What has happened:
3380   // 1) a new class dependee has been added
3381   // 2) dependee and all its super classes have been marked
3382   bool found_check = false;  // set true if we are upset
3383   for (Dependencies::DepStream deps(this); deps.next(); ) {
3384     // Evaluate only relevant dependencies.
3385     if (deps.spot_check_dependency_at(changes) != nullptr) {
3386       found_check = true;
3387       NOT_DEBUG(break);
3388     }
3389   }
3390   return found_check;
3391 }
3392 
3393 // Called from mark_for_deoptimization, when dependee is invalidated.
3394 bool nmethod::is_dependent_on_method(Method* dependee) {
3395   for (Dependencies::DepStream deps(this); deps.next(); ) {
3396     if (deps.type() != Dependencies::evol_method)
3397       continue;
3398     Method* method = deps.method_argument(0);
3399     if (method == dependee) return true;
3400   }
3401   return false;
3402 }
3403 
3404 void nmethod_init() {
3405   // make sure you didn't forget to adjust the filler fields
3406   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
3407 }
3408 
3409 // -----------------------------------------------------------------------------
3410 // Verification
3411 
3412 class VerifyOopsClosure: public OopClosure {
3413   nmethod* _nm;
3414   bool     _ok;
3415 public:
3416   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
3417   bool ok() { return _ok; }
3418   virtual void do_oop(oop* p) {
3419     if (oopDesc::is_oop_or_null(*p)) return;
3420     // Print diagnostic information before calling print_nmethod().
3421     // Assertions therein might prevent call from returning.
3422     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
3423                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
3424     if (_ok) {
3425       _nm->print_nmethod(true);
3426       _ok = false;
3427     }
3428   }
3429   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
3430 };
3431 
3432 class VerifyMetadataClosure: public MetadataClosure {
3433  public:
3434   void do_metadata(Metadata* md) {
3435     if (md->is_method()) {
3436       Method* method = (Method*)md;
3437       assert(!method->is_old(), "Should not be installing old methods");
3438     }
3439   }
3440 };
3441 
3442 
3443 void nmethod::verify() {
3444   if (is_not_entrant())
3445     return;
3446 
3447   // assert(oopDesc::is_oop(method()), "must be valid");
3448 
3449   ResourceMark rm;
3450 
3451   if (!CodeCache::contains(this)) {
3452     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
3453   }
3454 
3455   if(is_native_method() )
3456     return;
3457 
3458   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
3459   if (nm != this) {
3460     fatal("find_nmethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
3461   }
3462 
3463   // Verification can triggered during shutdown after AOTCodeCache is closed.
3464   // If the Scopes data is in the AOT code cache, then we should avoid verification during shutdown.
3465   if (!is_aot() || AOTCodeCache::is_on()) {
3466     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3467       if (! p->verify(this)) {
3468         tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
3469       }
3470     }
3471 
3472 #ifdef ASSERT
3473 #if INCLUDE_JVMCI
3474     {
3475       // Verify that implicit exceptions that deoptimize have a PcDesc and OopMap
3476       ImmutableOopMapSet* oms = oop_maps();
3477       ImplicitExceptionTable implicit_table(this);
3478       for (uint i = 0; i < implicit_table.len(); i++) {
3479         int exec_offset = (int) implicit_table.get_exec_offset(i);
3480         if (implicit_table.get_exec_offset(i) == implicit_table.get_cont_offset(i)) {
3481           assert(pc_desc_at(code_begin() + exec_offset) != nullptr, "missing PcDesc");
3482           bool found = false;
3483           for (int i = 0, imax = oms->count(); i < imax; i++) {
3484             if (oms->pair_at(i)->pc_offset() == exec_offset) {
3485               found = true;
3486               break;
3487             }
3488           }
3489           assert(found, "missing oopmap");
3490         }
3491       }
3492     }
3493 #endif
3494 #endif
3495   }
3496 
3497   VerifyOopsClosure voc(this);
3498   oops_do(&voc);
3499   assert(voc.ok(), "embedded oops must be OK");
3500   Universe::heap()->verify_nmethod(this);
3501 
3502   assert(_oops_do_mark_link == nullptr, "_oops_do_mark_link for %s should be nullptr but is " PTR_FORMAT,
3503          nm->method()->external_name(), p2i(_oops_do_mark_link));
3504   if (!is_aot() || AOTCodeCache::is_on()) {
3505     verify_scopes();
3506   }
3507 
3508   CompiledICLocker nm_verify(this);
3509   VerifyMetadataClosure vmc;
3510   metadata_do(&vmc);
3511 }
3512 
3513 
3514 void nmethod::verify_interrupt_point(address call_site, bool is_inline_cache) {
3515 
3516   // Verify IC only when nmethod installation is finished.
3517   if (!is_not_installed()) {
3518     if (CompiledICLocker::is_safe(this)) {
3519       if (is_inline_cache) {
3520         CompiledIC_at(this, call_site);
3521       } else {
3522         CompiledDirectCall::at(call_site);
3523       }
3524     } else {
3525       CompiledICLocker ml_verify(this);
3526       if (is_inline_cache) {
3527         CompiledIC_at(this, call_site);
3528       } else {
3529         CompiledDirectCall::at(call_site);
3530       }
3531     }
3532   }
3533 
3534   HandleMark hm(Thread::current());
3535 
3536   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
3537   assert(pd != nullptr, "PcDesc must exist");
3538   for (ScopeDesc* sd = new ScopeDesc(this, pd);
3539        !sd->is_top(); sd = sd->sender()) {
3540     sd->verify();
3541   }
3542 }
3543 
3544 void nmethod::verify_scopes() {
3545   if( !method() ) return;       // Runtime stubs have no scope
3546   if (method()->is_native()) return; // Ignore stub methods.
3547   // iterate through all interrupt point
3548   // and verify the debug information is valid.
3549   RelocIterator iter(this);
3550   while (iter.next()) {
3551     address stub = nullptr;
3552     switch (iter.type()) {
3553       case relocInfo::virtual_call_type:
3554         verify_interrupt_point(iter.addr(), true /* is_inline_cache */);
3555         break;
3556       case relocInfo::opt_virtual_call_type:
3557         stub = iter.opt_virtual_call_reloc()->static_stub();
3558         verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3559         break;
3560       case relocInfo::static_call_type:
3561         stub = iter.static_call_reloc()->static_stub();
3562         verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3563         break;
3564       case relocInfo::runtime_call_type:
3565       case relocInfo::runtime_call_w_cp_type: {
3566         address destination = iter.reloc()->value();
3567         // Right now there is no way to find out which entries support
3568         // an interrupt point.  It would be nice if we had this
3569         // information in a table.
3570         break;
3571       }
3572       default:
3573         break;
3574     }
3575     assert(stub == nullptr || stub_contains(stub), "static call stub outside stub section");
3576   }
3577 }
3578 
3579 
3580 // -----------------------------------------------------------------------------
3581 // Printing operations
3582 
3583 void nmethod::print_on_impl(outputStream* st) const {
3584   ResourceMark rm;
3585 
3586   st->print("Compiled method ");
3587 
3588   if (is_compiled_by_c1()) {
3589     st->print("(c1) ");
3590   } else if (is_compiled_by_c2()) {
3591     st->print("(c2) ");
3592   } else if (is_compiled_by_jvmci()) {
3593     st->print("(JVMCI) ");
3594   } else {
3595     st->print("(n/a) ");
3596   }
3597 
3598   print_on_with_msg(st, nullptr);
3599 
3600   if (WizardMode) {
3601     st->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
3602     st->print(" for method " INTPTR_FORMAT , p2i(method()));
3603     st->print(" { ");
3604     st->print_cr("%s ", state());
3605     st->print_cr("}:");
3606   }
3607   if (size              () > 0) st->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3608                                              p2i(this),
3609                                              p2i(this) + size(),
3610                                              size());
3611   if (consts_size       () > 0) st->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3612                                              p2i(consts_begin()),
3613                                              p2i(consts_end()),
3614                                              consts_size());
3615   if (insts_size        () > 0) st->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3616                                              p2i(insts_begin()),
3617                                              p2i(insts_end()),
3618                                              insts_size());
3619   if (stub_size         () > 0) st->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3620                                              p2i(stub_begin()),
3621                                              p2i(stub_end()),
3622                                              stub_size());
3623   if (oops_size         () > 0) st->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3624                                              p2i(oops_begin()),
3625                                              p2i(oops_end()),
3626                                              oops_size());
3627   if (mutable_data_size() > 0) st->print_cr(" mutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3628                                              p2i(mutable_data_begin()),
3629                                              p2i(mutable_data_end()),
3630                                              mutable_data_size());
3631   if (relocation_size() > 0)   st->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3632                                              p2i(relocation_begin()),
3633                                              p2i(relocation_end()),
3634                                              relocation_size());
3635   if (metadata_size     () > 0) st->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3636                                              p2i(metadata_begin()),
3637                                              p2i(metadata_end()),
3638                                              metadata_size());
3639 #if INCLUDE_JVMCI
3640   if (jvmci_data_size   () > 0) st->print_cr(" JVMCI data     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3641                                              p2i(jvmci_data_begin()),
3642                                              p2i(jvmci_data_end()),
3643                                              jvmci_data_size());
3644 #endif
3645   if (immutable_data_size() > 0) st->print_cr(" immutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3646                                              p2i(immutable_data_begin()),
3647                                              p2i(immutable_data_end()),
3648                                              immutable_data_size());
3649   if (dependencies_size () > 0) st->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3650                                              p2i(dependencies_begin()),
3651                                              p2i(dependencies_end()),
3652                                              dependencies_size());
3653   if (nul_chk_table_size() > 0) st->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3654                                              p2i(nul_chk_table_begin()),
3655                                              p2i(nul_chk_table_end()),
3656                                              nul_chk_table_size());
3657   if (handler_table_size() > 0) st->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3658                                              p2i(handler_table_begin()),
3659                                              p2i(handler_table_end()),
3660                                              handler_table_size());
3661   if (scopes_pcs_size   () > 0) st->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3662                                              p2i(scopes_pcs_begin()),
3663                                              p2i(scopes_pcs_end()),
3664                                              scopes_pcs_size());
3665   if (scopes_data_size  () > 0) st->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3666                                              p2i(scopes_data_begin()),
3667                                              p2i(scopes_data_end()),
3668                                              scopes_data_size());
3669 #if INCLUDE_JVMCI
3670   if (speculations_size () > 0) st->print_cr(" speculations   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3671                                              p2i(speculations_begin()),
3672                                              p2i(speculations_end()),
3673                                              speculations_size());
3674 #endif
3675   if (AOTCodeCache::is_on() && _aot_code_entry != nullptr) {
3676     _aot_code_entry->print(st);
3677   }
3678 }
3679 
3680 void nmethod::print_code() {
3681   ResourceMark m;
3682   ttyLocker ttyl;
3683   // Call the specialized decode method of this class.
3684   decode(tty);
3685 }
3686 
3687 #ifndef PRODUCT  // called InstanceKlass methods are available only then. Declared as PRODUCT_RETURN
3688 
3689 void nmethod::print_dependencies_on(outputStream* out) {
3690   ResourceMark rm;
3691   stringStream st;
3692   st.print_cr("Dependencies:");
3693   for (Dependencies::DepStream deps(this); deps.next(); ) {
3694     deps.print_dependency(&st);
3695     InstanceKlass* ctxk = deps.context_type();
3696     if (ctxk != nullptr) {
3697       if (ctxk->is_dependent_nmethod(this)) {
3698         st.print_cr("   [nmethod<=klass]%s", ctxk->external_name());
3699       }
3700     }
3701     deps.log_dependency();  // put it into the xml log also
3702   }
3703   out->print_raw(st.as_string());
3704 }
3705 #endif
3706 
3707 #if defined(SUPPORT_DATA_STRUCTS)
3708 
3709 // Print the oops from the underlying CodeBlob.
3710 void nmethod::print_oops(outputStream* st) {
3711   ResourceMark m;
3712   st->print("Oops:");
3713   if (oops_begin() < oops_end()) {
3714     st->cr();
3715     for (oop* p = oops_begin(); p < oops_end(); p++) {
3716       Disassembler::print_location((unsigned char*)p, (unsigned char*)oops_begin(), (unsigned char*)oops_end(), st, true, false);
3717       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3718       if (Universe::contains_non_oop_word(p)) {
3719         st->print_cr("NON_OOP");
3720         continue;  // skip non-oops
3721       }
3722       if (*p == nullptr) {
3723         st->print_cr("nullptr-oop");
3724         continue;  // skip non-oops
3725       }
3726       (*p)->print_value_on(st);
3727       st->cr();
3728     }
3729   } else {
3730     st->print_cr(" <list empty>");
3731   }
3732 }
3733 
3734 // Print metadata pool.
3735 void nmethod::print_metadata(outputStream* st) {
3736   ResourceMark m;
3737   st->print("Metadata:");
3738   if (metadata_begin() < metadata_end()) {
3739     st->cr();
3740     for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
3741       Disassembler::print_location((unsigned char*)p, (unsigned char*)metadata_begin(), (unsigned char*)metadata_end(), st, true, false);
3742       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3743       if (*p && *p != Universe::non_oop_word()) {
3744         (*p)->print_value_on(st);
3745       }
3746       st->cr();
3747     }
3748   } else {
3749     st->print_cr(" <list empty>");
3750   }
3751 }
3752 
3753 #ifndef PRODUCT  // ScopeDesc::print_on() is available only then. Declared as PRODUCT_RETURN
3754 void nmethod::print_scopes_on(outputStream* st) {
3755   // Find the first pc desc for all scopes in the code and print it.
3756   ResourceMark rm;
3757   st->print("scopes:");
3758   if (scopes_pcs_begin() < scopes_pcs_end()) {
3759     st->cr();
3760     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3761       if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
3762         continue;
3763 
3764       ScopeDesc* sd = scope_desc_at(p->real_pc(this));
3765       while (sd != nullptr) {
3766         sd->print_on(st, p);  // print output ends with a newline
3767         sd = sd->sender();
3768       }
3769     }
3770   } else {
3771     st->print_cr(" <list empty>");
3772   }
3773 }
3774 #endif
3775 
3776 #ifndef PRODUCT  // RelocIterator does support printing only then.
3777 void nmethod::print_relocations_on(outputStream* st) {
3778   ResourceMark m;       // in case methods get printed via the debugger
3779   st->print_cr("relocations:");
3780   RelocIterator iter(this);
3781   iter.print_on(st);
3782 }
3783 #endif
3784 
3785 void nmethod::print_pcs_on(outputStream* st) {
3786   ResourceMark m;       // in case methods get printed via debugger
3787   st->print("pc-bytecode offsets:");
3788   if (scopes_pcs_begin() < scopes_pcs_end()) {
3789     st->cr();
3790     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3791       p->print_on(st, this);  // print output ends with a newline
3792     }
3793   } else {
3794     st->print_cr(" <list empty>");
3795   }
3796 }
3797 
3798 void nmethod::print_handler_table() {
3799   ExceptionHandlerTable(this).print(code_begin());
3800 }
3801 
3802 void nmethod::print_nul_chk_table() {
3803   ImplicitExceptionTable(this).print(code_begin());
3804 }
3805 
3806 void nmethod::print_recorded_oop(int log_n, int i) {
3807   void* value;
3808 
3809   if (i == 0) {
3810     value = nullptr;
3811   } else {
3812     // Be careful around non-oop words. Don't create an oop
3813     // with that value, or it will assert in verification code.
3814     if (Universe::contains_non_oop_word(oop_addr_at(i))) {
3815       value = Universe::non_oop_word();
3816     } else {
3817       value = oop_at(i);
3818     }
3819   }
3820 
3821   tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(value));
3822 
3823   if (value == Universe::non_oop_word()) {
3824     tty->print("non-oop word");
3825   } else {
3826     if (value == nullptr) {
3827       tty->print("nullptr-oop");
3828     } else {
3829       oop_at(i)->print_value_on(tty);
3830     }
3831   }
3832 
3833   tty->cr();
3834 }
3835 
3836 void nmethod::print_recorded_oops() {
3837   const int n = oops_count();
3838   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3839   tty->print("Recorded oops:");
3840   if (n > 0) {
3841     tty->cr();
3842     for (int i = 0; i < n; i++) {
3843       print_recorded_oop(log_n, i);
3844     }
3845   } else {
3846     tty->print_cr(" <list empty>");
3847   }
3848 }
3849 
3850 void nmethod::print_recorded_metadata() {
3851   const int n = metadata_count();
3852   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3853   tty->print("Recorded metadata:");
3854   if (n > 0) {
3855     tty->cr();
3856     for (int i = 0; i < n; i++) {
3857       Metadata* m = metadata_at(i);
3858       tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(m));
3859       if (m == (Metadata*)Universe::non_oop_word()) {
3860         tty->print("non-metadata word");
3861       } else if (m == nullptr) {
3862         tty->print("nullptr-oop");
3863       } else {
3864         Metadata::print_value_on_maybe_null(tty, m);
3865       }
3866       tty->cr();
3867     }
3868   } else {
3869     tty->print_cr(" <list empty>");
3870   }
3871 }
3872 #endif
3873 
3874 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
3875 
3876 void nmethod::print_constant_pool(outputStream* st) {
3877   //-----------------------------------
3878   //---<  Print the constant pool  >---
3879   //-----------------------------------
3880   int consts_size = this->consts_size();
3881   if ( consts_size > 0 ) {
3882     unsigned char* cstart = this->consts_begin();
3883     unsigned char* cp     = cstart;
3884     unsigned char* cend   = cp + consts_size;
3885     unsigned int   bytes_per_line = 4;
3886     unsigned int   CP_alignment   = 8;
3887     unsigned int   n;
3888 
3889     st->cr();
3890 
3891     //---<  print CP header to make clear what's printed  >---
3892     if( ((uintptr_t)cp&(CP_alignment-1)) == 0 ) {
3893       n = bytes_per_line;
3894       st->print_cr("[Constant Pool]");
3895       Disassembler::print_location(cp, cstart, cend, st, true, true);
3896       Disassembler::print_hexdata(cp, n, st, true);
3897       st->cr();
3898     } else {
3899       n = (int)((uintptr_t)cp & (bytes_per_line-1));
3900       st->print_cr("[Constant Pool (unaligned)]");
3901     }
3902 
3903     //---<  print CP contents, bytes_per_line at a time  >---
3904     while (cp < cend) {
3905       Disassembler::print_location(cp, cstart, cend, st, true, false);
3906       Disassembler::print_hexdata(cp, n, st, false);
3907       cp += n;
3908       n   = bytes_per_line;
3909       st->cr();
3910     }
3911 
3912     //---<  Show potential alignment gap between constant pool and code  >---
3913     cend = code_begin();
3914     if( cp < cend ) {
3915       n = 4;
3916       st->print_cr("[Code entry alignment]");
3917       while (cp < cend) {
3918         Disassembler::print_location(cp, cstart, cend, st, false, false);
3919         cp += n;
3920         st->cr();
3921       }
3922     }
3923   } else {
3924     st->print_cr("[Constant Pool (empty)]");
3925   }
3926   st->cr();
3927 }
3928 
3929 #endif
3930 
3931 // Disassemble this nmethod.
3932 // Print additional debug information, if requested. This could be code
3933 // comments, block comments, profiling counters, etc.
3934 // The undisassembled format is useful no disassembler library is available.
3935 // The resulting hex dump (with markers) can be disassembled later, or on
3936 // another system, when/where a disassembler library is available.
3937 void nmethod::decode2(outputStream* ost) const {
3938 
3939   // Called from frame::back_trace_with_decode without ResourceMark.
3940   ResourceMark rm;
3941 
3942   // Make sure we have a valid stream to print on.
3943   outputStream* st = ost ? ost : tty;
3944 
3945 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) && ! defined(SUPPORT_ASSEMBLY)
3946   const bool use_compressed_format    = true;
3947   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3948                                                                   AbstractDisassembler::show_block_comment());
3949 #else
3950   const bool use_compressed_format    = Disassembler::is_abstract();
3951   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3952                                                                   AbstractDisassembler::show_block_comment());
3953 #endif
3954 
3955   st->cr();
3956   this->print_on(st);
3957   st->cr();
3958 
3959 #if defined(SUPPORT_ASSEMBLY)
3960   //----------------------------------
3961   //---<  Print real disassembly  >---
3962   //----------------------------------
3963   if (! use_compressed_format) {
3964     st->print_cr("[Disassembly]");
3965     Disassembler::decode(const_cast<nmethod*>(this), st);
3966     st->bol();
3967     st->print_cr("[/Disassembly]");
3968     return;
3969   }
3970 #endif
3971 
3972 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3973 
3974   // Compressed undisassembled disassembly format.
3975   // The following status values are defined/supported:
3976   //   = 0 - currently at bol() position, nothing printed yet on current line.
3977   //   = 1 - currently at position after print_location().
3978   //   > 1 - in the midst of printing instruction stream bytes.
3979   int        compressed_format_idx    = 0;
3980   int        code_comment_column      = 0;
3981   const int  instr_maxlen             = Assembler::instr_maxlen();
3982   const uint tabspacing               = 8;
3983   unsigned char* start = this->code_begin();
3984   unsigned char* p     = this->code_begin();
3985   unsigned char* end   = this->code_end();
3986   unsigned char* pss   = p; // start of a code section (used for offsets)
3987 
3988   if ((start == nullptr) || (end == nullptr)) {
3989     st->print_cr("PrintAssembly not possible due to uninitialized section pointers");
3990     return;
3991   }
3992 #endif
3993 
3994 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3995   //---<  plain abstract disassembly, no comments or anything, just section headers  >---
3996   if (use_compressed_format && ! compressed_with_comments) {
3997     const_cast<nmethod*>(this)->print_constant_pool(st);
3998 
3999     st->bol();
4000     st->cr();
4001     st->print_cr("Loading hsdis library failed, undisassembled code is shown in MachCode section");
4002     //---<  Open the output (Marker for post-mortem disassembler)  >---
4003     st->print_cr("[MachCode]");
4004     const char* header = nullptr;
4005     address p0 = p;
4006     while (p < end) {
4007       address pp = p;
4008       while ((p < end) && (header == nullptr)) {
4009         header = nmethod_section_label(p);
4010         pp  = p;
4011         p  += Assembler::instr_len(p);
4012       }
4013       if (pp > p0) {
4014         AbstractDisassembler::decode_range_abstract(p0, pp, start, end, st, Assembler::instr_maxlen());
4015         p0 = pp;
4016         p  = pp;
4017         header = nullptr;
4018       } else if (header != nullptr) {
4019         st->bol();
4020         st->print_cr("%s", header);
4021         header = nullptr;
4022       }
4023     }
4024     //---<  Close the output (Marker for post-mortem disassembler)  >---
4025     st->bol();
4026     st->print_cr("[/MachCode]");
4027     return;
4028   }
4029 #endif
4030 
4031 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
4032   //---<  abstract disassembly with comments and section headers merged in  >---
4033   if (compressed_with_comments) {
4034     const_cast<nmethod*>(this)->print_constant_pool(st);
4035 
4036     st->bol();
4037     st->cr();
4038     st->print_cr("Loading hsdis library failed, undisassembled code is shown in MachCode section");
4039     //---<  Open the output (Marker for post-mortem disassembler)  >---
4040     st->print_cr("[MachCode]");
4041     while ((p < end) && (p != nullptr)) {
4042       const int instruction_size_in_bytes = Assembler::instr_len(p);
4043 
4044       //---<  Block comments for nmethod. Interrupts instruction stream, if any.  >---
4045       // Outputs a bol() before and a cr() after, but only if a comment is printed.
4046       // Prints nmethod_section_label as well.
4047       if (AbstractDisassembler::show_block_comment()) {
4048         print_block_comment(st, p);
4049         if (st->position() == 0) {
4050           compressed_format_idx = 0;
4051         }
4052       }
4053 
4054       //---<  New location information after line break  >---
4055       if (compressed_format_idx == 0) {
4056         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
4057         compressed_format_idx = 1;
4058       }
4059 
4060       //---<  Code comment for current instruction. Address range [p..(p+len))  >---
4061       unsigned char* p_end = p + (ssize_t)instruction_size_in_bytes;
4062       S390_ONLY(if (p_end > end) p_end = end;) // avoid getting past the end
4063 
4064       if (AbstractDisassembler::show_comment() && const_cast<nmethod*>(this)->has_code_comment(p, p_end)) {
4065         //---<  interrupt instruction byte stream for code comment  >---
4066         if (compressed_format_idx > 1) {
4067           st->cr();  // interrupt byte stream
4068           st->cr();  // add an empty line
4069           code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
4070         }
4071         const_cast<nmethod*>(this)->print_code_comment_on(st, code_comment_column, p, p_end );
4072         st->bol();
4073         compressed_format_idx = 0;
4074       }
4075 
4076       //---<  New location information after line break  >---
4077       if (compressed_format_idx == 0) {
4078         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
4079         compressed_format_idx = 1;
4080       }
4081 
4082       //---<  Nicely align instructions for readability  >---
4083       if (compressed_format_idx > 1) {
4084         Disassembler::print_delimiter(st);
4085       }
4086 
4087       //---<  Now, finally, print the actual instruction bytes  >---
4088       unsigned char* p0 = p;
4089       p = Disassembler::decode_instruction_abstract(p, st, instruction_size_in_bytes, instr_maxlen);
4090       compressed_format_idx += (int)(p - p0);
4091 
4092       if (Disassembler::start_newline(compressed_format_idx-1)) {
4093         st->cr();
4094         compressed_format_idx = 0;
4095       }
4096     }
4097     //---<  Close the output (Marker for post-mortem disassembler)  >---
4098     st->bol();
4099     st->print_cr("[/MachCode]");
4100     return;
4101   }
4102 #endif
4103 }
4104 
4105 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
4106 
4107 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
4108   RelocIterator iter(this, begin, end);
4109   bool have_one = false;
4110   while (iter.next()) {
4111     have_one = true;
4112     switch (iter.type()) {
4113         case relocInfo::none: {
4114           // Skip it and check next
4115           break;
4116         }
4117         case relocInfo::oop_type: {
4118           // Get a non-resizable resource-allocated stringStream.
4119           // Our callees make use of (nested) ResourceMarks.
4120           stringStream st(NEW_RESOURCE_ARRAY(char, 1024), 1024);
4121           oop_Relocation* r = iter.oop_reloc();
4122           oop obj = r->oop_value();
4123           st.print("oop(");
4124           if (obj == nullptr) st.print("nullptr");
4125           else obj->print_value_on(&st);
4126           st.print(")");
4127           return st.as_string();
4128         }
4129         case relocInfo::metadata_type: {
4130           stringStream st;
4131           metadata_Relocation* r = iter.metadata_reloc();
4132           Metadata* obj = r->metadata_value();
4133           st.print("metadata(");
4134           if (obj == nullptr) st.print("nullptr");
4135           else obj->print_value_on(&st);
4136           st.print(")");
4137           return st.as_string();
4138         }
4139         case relocInfo::runtime_call_type:
4140         case relocInfo::runtime_call_w_cp_type: {
4141           stringStream st;
4142           st.print("runtime_call");
4143           CallRelocation* r = (CallRelocation*)iter.reloc();
4144           address dest = r->destination();
4145           if (StubRoutines::contains(dest)) {
4146             StubCodeDesc* desc = StubCodeDesc::desc_for(dest);
4147             if (desc == nullptr) {
4148               desc = StubCodeDesc::desc_for(dest + frame::pc_return_offset);
4149             }
4150             if (desc != nullptr) {
4151               st.print(" Stub::%s", desc->name());
4152               return st.as_string();
4153             }
4154           }
4155           CodeBlob* cb = CodeCache::find_blob(dest);
4156           if (cb != nullptr) {
4157             st.print(" %s", cb->name());
4158           } else {
4159             ResourceMark rm;
4160             const int buflen = 1024;
4161             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
4162             int offset;
4163             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
4164               st.print(" %s", buf);
4165               if (offset != 0) {
4166                 st.print("+%d", offset);
4167               }
4168             }
4169           }
4170           return st.as_string();
4171         }
4172         case relocInfo::virtual_call_type: {
4173           stringStream st;
4174           st.print_raw("virtual_call");
4175           virtual_call_Relocation* r = iter.virtual_call_reloc();
4176           Method* m = r->method_value();
4177           if (m != nullptr) {
4178             assert(m->is_method(), "");
4179             m->print_short_name(&st);
4180           }
4181           return st.as_string();
4182         }
4183         case relocInfo::opt_virtual_call_type: {
4184           stringStream st;
4185           st.print_raw("optimized virtual_call");
4186           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
4187           Method* m = r->method_value();
4188           if (m != nullptr) {
4189             assert(m->is_method(), "");
4190             m->print_short_name(&st);
4191           }
4192           return st.as_string();
4193         }
4194         case relocInfo::static_call_type: {
4195           stringStream st;
4196           st.print_raw("static_call");
4197           static_call_Relocation* r = iter.static_call_reloc();
4198           Method* m = r->method_value();
4199           if (m != nullptr) {
4200             assert(m->is_method(), "");
4201             m->print_short_name(&st);
4202           }
4203           return st.as_string();
4204         }
4205         case relocInfo::static_stub_type:      return "static_stub";
4206         case relocInfo::external_word_type:    return "external_word";
4207         case relocInfo::internal_word_type:    return "internal_word";
4208         case relocInfo::section_word_type:     return "section_word";
4209         case relocInfo::poll_type:             return "poll";
4210         case relocInfo::poll_return_type:      return "poll_return";
4211         case relocInfo::trampoline_stub_type:  return "trampoline_stub";
4212         case relocInfo::entry_guard_type:      return "entry_guard";
4213         case relocInfo::post_call_nop_type:    return "post_call_nop";
4214         case relocInfo::barrier_type: {
4215           barrier_Relocation* const reloc = iter.barrier_reloc();
4216           stringStream st;
4217           st.print("barrier format=%d", reloc->format());
4218           return st.as_string();
4219         }
4220 
4221         case relocInfo::type_mask:             return "type_bit_mask";
4222 
4223         default: {
4224           stringStream st;
4225           st.print("unknown relocInfo=%d", (int) iter.type());
4226           return st.as_string();
4227         }
4228     }
4229   }
4230   return have_one ? "other" : nullptr;
4231 }
4232 
4233 // Return the last scope in (begin..end]
4234 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
4235   PcDesc* p = pc_desc_near(begin+1);
4236   if (p != nullptr && p->real_pc(this) <= end) {
4237     return new ScopeDesc(this, p);
4238   }
4239   return nullptr;
4240 }
4241 
4242 const char* nmethod::nmethod_section_label(address pos) const {
4243   const char* label = nullptr;
4244   if (pos == code_begin())                                              label = "[Instructions begin]";
4245   if (pos == entry_point())                                             label = "[Entry Point]";
4246   if (pos == verified_entry_point())                                    label = "[Verified Entry Point]";
4247   if (pos == consts_begin() && pos != insts_begin())                    label = "[Constants]";
4248   // Check stub_code before checking exception_handler or deopt_handler.
4249   if (pos == this->stub_begin())                                        label = "[Stub Code]";
4250   if (JVMCI_ONLY(_exception_offset >= 0 &&) pos == exception_begin())          label = "[Exception Handler]";
4251   if (JVMCI_ONLY(_deopt_handler_entry_offset != -1 &&) pos == deopt_handler_entry()) label = "[Deopt Handler Entry Point]";
4252   return label;
4253 }
4254 
4255 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels) const {
4256   if (print_section_labels) {
4257     const char* label = nmethod_section_label(block_begin);
4258     if (label != nullptr) {
4259       stream->bol();
4260       stream->print_cr("%s", label);
4261     }
4262   }
4263 
4264   if (block_begin == entry_point()) {
4265     Method* m = method();
4266     if (m != nullptr) {
4267       stream->print("  # ");
4268       m->print_value_on(stream);
4269       stream->cr();
4270     }
4271     if (m != nullptr && !is_osr_method()) {
4272       ResourceMark rm;
4273       int sizeargs = m->size_of_parameters();
4274       BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
4275       VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
4276       {
4277         int sig_index = 0;
4278         if (!m->is_static())
4279           sig_bt[sig_index++] = T_OBJECT; // 'this'
4280         for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
4281           BasicType t = ss.type();
4282           sig_bt[sig_index++] = t;
4283           if (type2size[t] == 2) {
4284             sig_bt[sig_index++] = T_VOID;
4285           } else {
4286             assert(type2size[t] == 1, "size is 1 or 2");
4287           }
4288         }
4289         assert(sig_index == sizeargs, "");
4290       }
4291       const char* spname = "sp"; // make arch-specific?
4292       SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs);
4293       int stack_slot_offset = this->frame_size() * wordSize;
4294       int tab1 = 14, tab2 = 24;
4295       int sig_index = 0;
4296       int arg_index = (m->is_static() ? 0 : -1);
4297       bool did_old_sp = false;
4298       for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
4299         bool at_this = (arg_index == -1);
4300         bool at_old_sp = false;
4301         BasicType t = (at_this ? T_OBJECT : ss.type());
4302         assert(t == sig_bt[sig_index], "sigs in sync");
4303         if (at_this)
4304           stream->print("  # this: ");
4305         else
4306           stream->print("  # parm%d: ", arg_index);
4307         stream->move_to(tab1);
4308         VMReg fst = regs[sig_index].first();
4309         VMReg snd = regs[sig_index].second();
4310         if (fst->is_reg()) {
4311           stream->print("%s", fst->name());
4312           if (snd->is_valid())  {
4313             stream->print(":%s", snd->name());
4314           }
4315         } else if (fst->is_stack()) {
4316           int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
4317           if (offset == stack_slot_offset)  at_old_sp = true;
4318           stream->print("[%s+0x%x]", spname, offset);
4319         } else {
4320           stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
4321         }
4322         stream->print(" ");
4323         stream->move_to(tab2);
4324         stream->print("= ");
4325         if (at_this) {
4326           m->method_holder()->print_value_on(stream);
4327         } else {
4328           bool did_name = false;
4329           if (!at_this && ss.is_reference()) {
4330             Symbol* name = ss.as_symbol();
4331             name->print_value_on(stream);
4332             did_name = true;
4333           }
4334           if (!did_name)
4335             stream->print("%s", type2name(t));
4336         }
4337         if (at_old_sp) {
4338           stream->print("  (%s of caller)", spname);
4339           did_old_sp = true;
4340         }
4341         stream->cr();
4342         sig_index += type2size[t];
4343         arg_index += 1;
4344         if (!at_this)  ss.next();
4345       }
4346       if (!did_old_sp) {
4347         stream->print("  # ");
4348         stream->move_to(tab1);
4349         stream->print("[%s+0x%x]", spname, stack_slot_offset);
4350         stream->print("  (%s of caller)", spname);
4351         stream->cr();
4352       }
4353     }
4354   }
4355 }
4356 
4357 // Returns whether this nmethod has code comments.
4358 bool nmethod::has_code_comment(address begin, address end) {
4359   // scopes?
4360   ScopeDesc* sd  = scope_desc_in(begin, end);
4361   if (sd != nullptr) return true;
4362 
4363   // relocations?
4364   const char* str = reloc_string_for(begin, end);
4365   if (str != nullptr) return true;
4366 
4367   // implicit exceptions?
4368   int cont_offset = ImplicitExceptionTable(this).continuation_offset((uint)(begin - code_begin()));
4369   if (cont_offset != 0) return true;
4370 
4371   return false;
4372 }
4373 
4374 void nmethod::print_code_comment_on(outputStream* st, int column, address begin, address end) {
4375   ImplicitExceptionTable implicit_table(this);
4376   int pc_offset = (int)(begin - code_begin());
4377   int cont_offset = implicit_table.continuation_offset(pc_offset);
4378   bool oop_map_required = false;
4379   if (cont_offset != 0) {
4380     st->move_to(column, 6, 0);
4381     if (pc_offset == cont_offset) {
4382       st->print("; implicit exception: deoptimizes");
4383       oop_map_required = true;
4384     } else {
4385       st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
4386     }
4387   }
4388 
4389   // Find an oopmap in (begin, end].  We use the odd half-closed
4390   // interval so that oop maps and scope descs which are tied to the
4391   // byte after a call are printed with the call itself.  OopMaps
4392   // associated with implicit exceptions are printed with the implicit
4393   // instruction.
4394   address base = code_begin();
4395   ImmutableOopMapSet* oms = oop_maps();
4396   if (oms != nullptr) {
4397     for (int i = 0, imax = oms->count(); i < imax; i++) {
4398       const ImmutableOopMapPair* pair = oms->pair_at(i);
4399       const ImmutableOopMap* om = pair->get_from(oms);
4400       address pc = base + pair->pc_offset();
4401       if (pc >= begin) {
4402 #if INCLUDE_JVMCI
4403         bool is_implicit_deopt = implicit_table.continuation_offset(pair->pc_offset()) == (uint) pair->pc_offset();
4404 #else
4405         bool is_implicit_deopt = false;
4406 #endif
4407         if (is_implicit_deopt ? pc == begin : pc > begin && pc <= end) {
4408           st->move_to(column, 6, 0);
4409           st->print("; ");
4410           om->print_on(st);
4411           oop_map_required = false;
4412         }
4413       }
4414       if (pc > end) {
4415         break;
4416       }
4417     }
4418   }
4419   assert(!oop_map_required, "missed oopmap");
4420 
4421   Thread* thread = Thread::current();
4422 
4423   // Print any debug info present at this pc.
4424   ScopeDesc* sd  = scope_desc_in(begin, end);
4425   if (sd != nullptr) {
4426     st->move_to(column, 6, 0);
4427     if (sd->bci() == SynchronizationEntryBCI) {
4428       st->print(";*synchronization entry");
4429     } else if (sd->bci() == AfterBci) {
4430       st->print(";* method exit (unlocked if synchronized)");
4431     } else if (sd->bci() == UnwindBci) {
4432       st->print(";* unwind (locked if synchronized)");
4433     } else if (sd->bci() == AfterExceptionBci) {
4434       st->print(";* unwind (unlocked if synchronized)");
4435     } else if (sd->bci() == UnknownBci) {
4436       st->print(";* unknown");
4437     } else if (sd->bci() == InvalidFrameStateBci) {
4438       st->print(";* invalid frame state");
4439     } else {
4440       if (sd->method() == nullptr) {
4441         st->print("method is nullptr");
4442       } else if (sd->method()->is_native()) {
4443         st->print("method is native");
4444       } else {
4445         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
4446         st->print(";*%s", Bytecodes::name(bc));
4447         switch (bc) {
4448         case Bytecodes::_invokevirtual:
4449         case Bytecodes::_invokespecial:
4450         case Bytecodes::_invokestatic:
4451         case Bytecodes::_invokeinterface:
4452           {
4453             Bytecode_invoke invoke(methodHandle(thread, sd->method()), sd->bci());
4454             st->print(" ");
4455             if (invoke.name() != nullptr)
4456               invoke.name()->print_symbol_on(st);
4457             else
4458               st->print("<UNKNOWN>");
4459             break;
4460           }
4461         case Bytecodes::_getfield:
4462         case Bytecodes::_putfield:
4463         case Bytecodes::_getstatic:
4464         case Bytecodes::_putstatic:
4465           {
4466             Bytecode_field field(methodHandle(thread, sd->method()), sd->bci());
4467             st->print(" ");
4468             if (field.name() != nullptr)
4469               field.name()->print_symbol_on(st);
4470             else
4471               st->print("<UNKNOWN>");
4472           }
4473         default:
4474           break;
4475         }
4476       }
4477       st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
4478     }
4479 
4480     // Print all scopes
4481     for (;sd != nullptr; sd = sd->sender()) {
4482       st->move_to(column, 6, 0);
4483       st->print("; -");
4484       if (sd->should_reexecute()) {
4485         st->print(" (reexecute)");
4486       }
4487       if (sd->method() == nullptr) {
4488         st->print("method is nullptr");
4489       } else {
4490         sd->method()->print_short_name(st);
4491       }
4492       int lineno = sd->method()->line_number_from_bci(sd->bci());
4493       if (lineno != -1) {
4494         st->print("@%d (line %d)", sd->bci(), lineno);
4495       } else {
4496         st->print("@%d", sd->bci());
4497       }
4498       st->cr();
4499     }
4500   }
4501 
4502   // Print relocation information
4503   // Prevent memory leak: allocating without ResourceMark.
4504   ResourceMark rm;
4505   const char* str = reloc_string_for(begin, end);
4506   if (str != nullptr) {
4507     if (sd != nullptr) st->cr();
4508     st->move_to(column, 6, 0);
4509     st->print(";   {%s}", str);
4510   }
4511 }
4512 
4513 #endif
4514 
4515 address nmethod::call_instruction_address(address pc) const {
4516   if (NativeCall::is_call_before(pc)) {
4517     NativeCall *ncall = nativeCall_before(pc);
4518     return ncall->instruction_address();
4519   }
4520   return nullptr;
4521 }
4522 
4523 void nmethod::print_value_on_impl(outputStream* st) const {
4524   st->print_cr("nmethod");
4525 #if defined(SUPPORT_DATA_STRUCTS)
4526   print_on_with_msg(st, nullptr);
4527 #endif
4528 }
4529 
4530 void nmethod::print_code_snippet(outputStream* st, address addr) const {
4531   if (entry_point() <= addr && addr < code_end()) {
4532     // Pointing into the nmethod's code. Try to disassemble some instructions around addr.
4533     // Determine conservative start and end points.
4534     address start;
4535     if (frame_complete_offset() != CodeOffsets::frame_never_safe &&
4536         addr >= code_begin() + frame_complete_offset()) {
4537       start = code_begin() + frame_complete_offset();
4538     } else {
4539       start = (addr < verified_entry_point()) ? entry_point() : verified_entry_point();
4540     }
4541     address start_for_hex_dump = start; // We can choose a different starting point for hex dump, below.
4542     address end = code_end();
4543 
4544     // Try using relocations to find closer instruction start and end points.
4545     // (Some platforms have variable length instructions and can only
4546     // disassemble correctly at instruction start addresses.)
4547     RelocIterator iter((nmethod*)this, start);
4548     while (iter.next() && iter.addr() < addr) { // find relocation before addr
4549       // Note: There's a relocation which doesn't point to an instruction start:
4550       // ZBarrierRelocationFormatStoreGoodAfterMov with ZGC on x86_64
4551       // We could detect and skip it, but hex dump is still usable when
4552       // disassembler produces garbage in such a very rare case.
4553       start = iter.addr();
4554       // We want at least 64 Bytes ahead in hex dump.
4555       if (iter.addr() <= (addr - 64)) start_for_hex_dump = iter.addr();
4556     }
4557     if (iter.has_current()) {
4558       if (iter.addr() == addr) iter.next(); // find relocation after addr
4559       if (iter.has_current()) end = iter.addr();
4560     }
4561 
4562     // Always print hex. Disassembler may still have problems when hitting an incorrect instruction start.
4563     os::print_hex_dump(st, start_for_hex_dump, end, 1, /* print_ascii=*/false);
4564     if (!Disassembler::is_abstract()) {
4565       Disassembler::decode(start, end, st);
4566     }
4567   }
4568 }
4569 
4570 #ifndef PRODUCT
4571 
4572 void nmethod::print_calls(outputStream* st) {
4573   RelocIterator iter(this);
4574   while (iter.next()) {
4575     switch (iter.type()) {
4576     case relocInfo::virtual_call_type: {
4577       CompiledICLocker ml_verify(this);
4578       CompiledIC_at(&iter)->print();
4579       break;
4580     }
4581     case relocInfo::static_call_type:
4582     case relocInfo::opt_virtual_call_type:
4583       st->print_cr("Direct call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
4584       CompiledDirectCall::at(iter.reloc())->print();
4585       break;
4586     default:
4587       break;
4588     }
4589   }
4590 }
4591 
4592 void nmethod::print_statistics() {
4593   ttyLocker ttyl;
4594   if (xtty != nullptr)  xtty->head("statistics type='nmethod'");
4595   native_nmethod_stats.print_native_nmethod_stats();
4596 #ifdef COMPILER1
4597   c1_java_nmethod_stats.print_nmethod_stats("C1");
4598 #endif
4599 #ifdef COMPILER2
4600   c2_java_nmethod_stats.print_nmethod_stats("C2");
4601 #endif
4602 #if INCLUDE_JVMCI
4603   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
4604 #endif
4605   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
4606   DebugInformationRecorder::print_statistics();
4607   pc_nmethod_stats.print_pc_stats();
4608   Dependencies::print_statistics();
4609   ExternalsRecorder::print_statistics();
4610   if (xtty != nullptr)  xtty->tail("statistics");
4611 }
4612 
4613 #endif // !PRODUCT
4614 
4615 #if INCLUDE_JVMCI
4616 void nmethod::update_speculation(JavaThread* thread) {
4617   jlong speculation = thread->pending_failed_speculation();
4618   if (speculation != 0) {
4619     guarantee(jvmci_nmethod_data() != nullptr, "failed speculation in nmethod without failed speculation list");
4620     jvmci_nmethod_data()->add_failed_speculation(this, speculation);
4621     thread->set_pending_failed_speculation(0);
4622   }
4623 }
4624 
4625 const char* nmethod::jvmci_name() {
4626   if (jvmci_nmethod_data() != nullptr) {
4627     return jvmci_nmethod_data()->name();
4628   }
4629   return nullptr;
4630 }
4631 
4632 bool nmethod::jvmci_skip_profile_deopt() const {
4633   return jvmci_nmethod_data() != nullptr && !jvmci_nmethod_data()->profile_deopt();
4634 }
4635 #endif
4636 
4637 void nmethod::prepare_for_archiving_impl() {
4638   CodeBlob::prepare_for_archiving_impl();
4639   _deoptimization_generation = 0;
4640   _gc_epoch = 0;
4641   _method_profiling_count = 0;
4642   _osr_link = nullptr;
4643   _method = nullptr;
4644   _immutable_data = nullptr;
4645   _pc_desc_container = nullptr;
4646   _exception_cache = nullptr;
4647   _gc_data = nullptr;
4648   _oops_do_mark_link = nullptr;
4649   _compiled_ic_data = nullptr;
4650   _osr_entry_point = nullptr;
4651   _compile_id = -1;
4652   _deoptimization_status = not_marked;
4653   _is_unloading_state = 0;
4654   _state = not_installed;
4655 }