1 /*
   2  * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "asm/assembler.inline.hpp"
  27 #include "code/codeCache.hpp"
  28 #include "code/compiledIC.hpp"
  29 #include "code/dependencies.hpp"
  30 #include "code/nativeInst.hpp"
  31 #include "code/nmethod.inline.hpp"
  32 #include "code/scopeDesc.hpp"
  33 #include "compiler/abstractCompiler.hpp"
  34 #include "compiler/compilationLog.hpp"
  35 #include "compiler/compileBroker.hpp"
  36 #include "compiler/compileLog.hpp"
  37 #include "compiler/compileTask.hpp"
  38 #include "compiler/compilerDirectives.hpp"
  39 #include "compiler/compilerOracle.hpp"
  40 #include "compiler/directivesParser.hpp"
  41 #include "compiler/disassembler.hpp"
  42 #include "compiler/oopMap.inline.hpp"
  43 #include "gc/shared/barrierSet.hpp"
  44 #include "gc/shared/barrierSetNMethod.hpp"
  45 #include "gc/shared/classUnloadingContext.hpp"
  46 #include "gc/shared/collectedHeap.hpp"
  47 #include "interpreter/bytecode.inline.hpp"
  48 #include "jvm.h"
  49 #include "logging/log.hpp"
  50 #include "logging/logStream.hpp"
  51 #include "memory/allocation.inline.hpp"
  52 #include "memory/resourceArea.hpp"
  53 #include "memory/universe.hpp"
  54 #include "oops/access.inline.hpp"
  55 #include "oops/klass.inline.hpp"
  56 #include "oops/method.inline.hpp"
  57 #include "oops/methodData.hpp"
  58 #include "oops/oop.inline.hpp"
  59 #include "oops/weakHandle.inline.hpp"
  60 #include "prims/jvmtiImpl.hpp"
  61 #include "prims/jvmtiThreadState.hpp"
  62 #include "prims/methodHandles.hpp"
  63 #include "runtime/continuation.hpp"
  64 #include "runtime/atomic.hpp"
  65 #include "runtime/deoptimization.hpp"
  66 #include "runtime/flags/flagSetting.hpp"
  67 #include "runtime/frame.inline.hpp"
  68 #include "runtime/handles.inline.hpp"
  69 #include "runtime/jniHandles.inline.hpp"
  70 #include "runtime/orderAccess.hpp"
  71 #include "runtime/os.hpp"
  72 #include "runtime/safepointVerifiers.hpp"
  73 #include "runtime/serviceThread.hpp"
  74 #include "runtime/sharedRuntime.hpp"
  75 #include "runtime/signature.hpp"
  76 #include "runtime/threadWXSetters.inline.hpp"
  77 #include "runtime/vmThread.hpp"
  78 #include "utilities/align.hpp"
  79 #include "utilities/copy.hpp"
  80 #include "utilities/dtrace.hpp"
  81 #include "utilities/events.hpp"
  82 #include "utilities/globalDefinitions.hpp"
  83 #include "utilities/resourceHash.hpp"
  84 #include "utilities/xmlstream.hpp"
  85 #if INCLUDE_JVMCI
  86 #include "jvmci/jvmciRuntime.hpp"
  87 #endif
  88 
  89 #ifdef DTRACE_ENABLED
  90 
  91 // Only bother with this argument setup if dtrace is available
  92 
  93 #define DTRACE_METHOD_UNLOAD_PROBE(method)                                \
  94   {                                                                       \
  95     Method* m = (method);                                                 \
  96     if (m != nullptr) {                                                   \
  97       Symbol* klass_name = m->klass_name();                               \
  98       Symbol* name = m->name();                                           \
  99       Symbol* signature = m->signature();                                 \
 100       HOTSPOT_COMPILED_METHOD_UNLOAD(                                     \
 101         (char *) klass_name->bytes(), klass_name->utf8_length(),          \
 102         (char *) name->bytes(), name->utf8_length(),                      \
 103         (char *) signature->bytes(), signature->utf8_length());           \
 104     }                                                                     \
 105   }
 106 
 107 #else //  ndef DTRACE_ENABLED
 108 
 109 #define DTRACE_METHOD_UNLOAD_PROBE(method)
 110 
 111 #endif
 112 
 113 // Cast from int value to narrow type
 114 #define CHECKED_CAST(result, T, thing)      \
 115   result = static_cast<T>(thing); \
 116   assert(static_cast<int>(result) == thing, "failed: %d != %d", static_cast<int>(result), thing);
 117 
 118 //---------------------------------------------------------------------------------
 119 // NMethod statistics
 120 // They are printed under various flags, including:
 121 //   PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
 122 // (In the latter two cases, they like other stats are printed to the log only.)
 123 
 124 #ifndef PRODUCT
 125 // These variables are put into one block to reduce relocations
 126 // and make it simpler to print from the debugger.
 127 struct java_nmethod_stats_struct {
 128   uint nmethod_count;
 129   uint total_nm_size;
 130   uint total_immut_size;
 131   uint relocation_size;
 132   uint consts_size;
 133   uint insts_size;
 134   uint stub_size;
 135   uint oops_size;
 136   uint metadata_size;
 137   uint dependencies_size;
 138   uint nul_chk_table_size;
 139   uint handler_table_size;
 140   uint scopes_pcs_size;
 141   uint scopes_data_size;
 142 #if INCLUDE_JVMCI
 143   uint speculations_size;
 144   uint jvmci_data_size;
 145 #endif
 146 
 147   void note_nmethod(nmethod* nm) {
 148     nmethod_count += 1;
 149     total_nm_size       += nm->size();
 150     total_immut_size    += nm->immutable_data_size();
 151     relocation_size     += nm->relocation_size();
 152     consts_size         += nm->consts_size();
 153     insts_size          += nm->insts_size();
 154     stub_size           += nm->stub_size();
 155     oops_size           += nm->oops_size();
 156     metadata_size       += nm->metadata_size();
 157     scopes_data_size    += nm->scopes_data_size();
 158     scopes_pcs_size     += nm->scopes_pcs_size();
 159     dependencies_size   += nm->dependencies_size();
 160     handler_table_size  += nm->handler_table_size();
 161     nul_chk_table_size  += nm->nul_chk_table_size();
 162 #if INCLUDE_JVMCI
 163     speculations_size   += nm->speculations_size();
 164     jvmci_data_size     += nm->jvmci_data_size();
 165 #endif
 166   }
 167   void print_nmethod_stats(const char* name) {
 168     if (nmethod_count == 0)  return;
 169     tty->print_cr("Statistics for %u bytecoded nmethods for %s:", nmethod_count, name);
 170     uint total_size = total_nm_size + total_immut_size;
 171     if (total_nm_size != 0) {
 172       tty->print_cr(" total size      = %u (100%%)", total_size);
 173       tty->print_cr(" in CodeCache    = %u (%f%%)", total_nm_size, (total_nm_size * 100.0f)/total_size);
 174     }
 175     uint header_size = (uint)(nmethod_count * sizeof(nmethod));
 176     if (nmethod_count != 0) {
 177       tty->print_cr("   header        = %u (%f%%)", header_size, (header_size * 100.0f)/total_nm_size);
 178     }
 179     if (relocation_size != 0) {
 180       tty->print_cr("   relocation    = %u (%f%%)", relocation_size, (relocation_size * 100.0f)/total_nm_size);
 181     }
 182     if (consts_size != 0) {
 183       tty->print_cr("   constants     = %u (%f%%)", consts_size, (consts_size * 100.0f)/total_nm_size);
 184     }
 185     if (insts_size != 0) {
 186       tty->print_cr("   main code     = %u (%f%%)", insts_size, (insts_size * 100.0f)/total_nm_size);
 187     }
 188     if (stub_size != 0) {
 189       tty->print_cr("   stub code     = %u (%f%%)", stub_size, (stub_size * 100.0f)/total_nm_size);
 190     }
 191     if (oops_size != 0) {
 192       tty->print_cr("   oops          = %u (%f%%)", oops_size, (oops_size * 100.0f)/total_nm_size);
 193     }
 194     if (metadata_size != 0) {
 195       tty->print_cr("   metadata      = %u (%f%%)", metadata_size, (metadata_size * 100.0f)/total_nm_size);
 196     }
 197 #if INCLUDE_JVMCI
 198     if (jvmci_data_size != 0) {
 199       tty->print_cr("   JVMCI data    = %u (%f%%)", jvmci_data_size, (jvmci_data_size * 100.0f)/total_nm_size);
 200     }
 201 #endif
 202     if (total_immut_size != 0) {
 203       tty->print_cr(" immutable data  = %u (%f%%)", total_immut_size, (total_immut_size * 100.0f)/total_size);
 204     }
 205     if (dependencies_size != 0) {
 206       tty->print_cr("   dependencies  = %u (%f%%)", dependencies_size, (dependencies_size * 100.0f)/total_immut_size);
 207     }
 208     if (nul_chk_table_size != 0) {
 209       tty->print_cr("   nul chk table = %u (%f%%)", nul_chk_table_size, (nul_chk_table_size * 100.0f)/total_immut_size);
 210     }
 211     if (handler_table_size != 0) {
 212       tty->print_cr("   handler table = %u (%f%%)", handler_table_size, (handler_table_size * 100.0f)/total_immut_size);
 213     }
 214     if (scopes_pcs_size != 0) {
 215       tty->print_cr("   scopes pcs    = %u (%f%%)", scopes_pcs_size, (scopes_pcs_size * 100.0f)/total_immut_size);
 216     }
 217     if (scopes_data_size != 0) {
 218       tty->print_cr("   scopes data   = %u (%f%%)", scopes_data_size, (scopes_data_size * 100.0f)/total_immut_size);
 219     }
 220 #if INCLUDE_JVMCI
 221     if (speculations_size != 0) {
 222       tty->print_cr("   speculations  = %u (%f%%)", speculations_size, (speculations_size * 100.0f)/total_immut_size);
 223     }
 224 #endif
 225   }
 226 };
 227 
 228 struct native_nmethod_stats_struct {
 229   uint native_nmethod_count;
 230   uint native_total_size;
 231   uint native_relocation_size;
 232   uint native_insts_size;
 233   uint native_oops_size;
 234   uint native_metadata_size;
 235   void note_native_nmethod(nmethod* nm) {
 236     native_nmethod_count += 1;
 237     native_total_size       += nm->size();
 238     native_relocation_size  += nm->relocation_size();
 239     native_insts_size       += nm->insts_size();
 240     native_oops_size        += nm->oops_size();
 241     native_metadata_size    += nm->metadata_size();
 242   }
 243   void print_native_nmethod_stats() {
 244     if (native_nmethod_count == 0)  return;
 245     tty->print_cr("Statistics for %u native nmethods:", native_nmethod_count);
 246     if (native_total_size != 0)       tty->print_cr(" N. total size  = %u", native_total_size);
 247     if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %u", native_relocation_size);
 248     if (native_insts_size != 0)       tty->print_cr(" N. main code   = %u", native_insts_size);
 249     if (native_oops_size != 0)        tty->print_cr(" N. oops        = %u", native_oops_size);
 250     if (native_metadata_size != 0)    tty->print_cr(" N. metadata    = %u", native_metadata_size);
 251   }
 252 };
 253 
 254 struct pc_nmethod_stats_struct {
 255   uint pc_desc_init;     // number of initialization of cache (= number of caches)
 256   uint pc_desc_queries;  // queries to nmethod::find_pc_desc
 257   uint pc_desc_approx;   // number of those which have approximate true
 258   uint pc_desc_repeats;  // number of _pc_descs[0] hits
 259   uint pc_desc_hits;     // number of LRU cache hits
 260   uint pc_desc_tests;    // total number of PcDesc examinations
 261   uint pc_desc_searches; // total number of quasi-binary search steps
 262   uint pc_desc_adds;     // number of LUR cache insertions
 263 
 264   void print_pc_stats() {
 265     tty->print_cr("PcDesc Statistics:  %u queries, %.2f comparisons per query",
 266                   pc_desc_queries,
 267                   (double)(pc_desc_tests + pc_desc_searches)
 268                   / pc_desc_queries);
 269     tty->print_cr("  caches=%d queries=%u/%u, hits=%u+%u, tests=%u+%u, adds=%u",
 270                   pc_desc_init,
 271                   pc_desc_queries, pc_desc_approx,
 272                   pc_desc_repeats, pc_desc_hits,
 273                   pc_desc_tests, pc_desc_searches, pc_desc_adds);
 274   }
 275 };
 276 
 277 #ifdef COMPILER1
 278 static java_nmethod_stats_struct c1_java_nmethod_stats;
 279 #endif
 280 #ifdef COMPILER2
 281 static java_nmethod_stats_struct c2_java_nmethod_stats;
 282 #endif
 283 #if INCLUDE_JVMCI
 284 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
 285 #endif
 286 static java_nmethod_stats_struct unknown_java_nmethod_stats;
 287 
 288 static native_nmethod_stats_struct native_nmethod_stats;
 289 static pc_nmethod_stats_struct pc_nmethod_stats;
 290 
 291 static void note_java_nmethod(nmethod* nm) {
 292 #ifdef COMPILER1
 293   if (nm->is_compiled_by_c1()) {
 294     c1_java_nmethod_stats.note_nmethod(nm);
 295   } else
 296 #endif
 297 #ifdef COMPILER2
 298   if (nm->is_compiled_by_c2()) {
 299     c2_java_nmethod_stats.note_nmethod(nm);
 300   } else
 301 #endif
 302 #if INCLUDE_JVMCI
 303   if (nm->is_compiled_by_jvmci()) {
 304     jvmci_java_nmethod_stats.note_nmethod(nm);
 305   } else
 306 #endif
 307   {
 308     unknown_java_nmethod_stats.note_nmethod(nm);
 309   }
 310 }
 311 #endif // !PRODUCT
 312 
 313 //---------------------------------------------------------------------------------
 314 
 315 
 316 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
 317   assert(pc != nullptr, "Must be non null");
 318   assert(exception.not_null(), "Must be non null");
 319   assert(handler != nullptr, "Must be non null");
 320 
 321   _count = 0;
 322   _exception_type = exception->klass();
 323   _next = nullptr;
 324   _purge_list_next = nullptr;
 325 
 326   add_address_and_handler(pc,handler);
 327 }
 328 
 329 
 330 address ExceptionCache::match(Handle exception, address pc) {
 331   assert(pc != nullptr,"Must be non null");
 332   assert(exception.not_null(),"Must be non null");
 333   if (exception->klass() == exception_type()) {
 334     return (test_address(pc));
 335   }
 336 
 337   return nullptr;
 338 }
 339 
 340 
 341 bool ExceptionCache::match_exception_with_space(Handle exception) {
 342   assert(exception.not_null(),"Must be non null");
 343   if (exception->klass() == exception_type() && count() < cache_size) {
 344     return true;
 345   }
 346   return false;
 347 }
 348 
 349 
 350 address ExceptionCache::test_address(address addr) {
 351   int limit = count();
 352   for (int i = 0; i < limit; i++) {
 353     if (pc_at(i) == addr) {
 354       return handler_at(i);
 355     }
 356   }
 357   return nullptr;
 358 }
 359 
 360 
 361 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
 362   if (test_address(addr) == handler) return true;
 363 
 364   int index = count();
 365   if (index < cache_size) {
 366     set_pc_at(index, addr);
 367     set_handler_at(index, handler);
 368     increment_count();
 369     return true;
 370   }
 371   return false;
 372 }
 373 
 374 ExceptionCache* ExceptionCache::next() {
 375   return Atomic::load(&_next);
 376 }
 377 
 378 void ExceptionCache::set_next(ExceptionCache *ec) {
 379   Atomic::store(&_next, ec);
 380 }
 381 
 382 //-----------------------------------------------------------------------------
 383 
 384 
 385 // Helper used by both find_pc_desc methods.
 386 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
 387   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
 388   if (!approximate) {
 389     return pc->pc_offset() == pc_offset;
 390   } else {
 391     return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
 392   }
 393 }
 394 
 395 void PcDescCache::init_to(PcDesc* initial_pc_desc) {
 396   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_init);
 397   // initialize the cache by filling it with benign (non-null) values
 398   assert(initial_pc_desc != nullptr && initial_pc_desc->pc_offset() == PcDesc::lower_offset_limit,
 399          "must start with a sentinel");
 400   for (int i = 0; i < cache_size; i++) {
 401     _pc_descs[i] = initial_pc_desc;
 402   }
 403 }
 404 
 405 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
 406   // Note: one might think that caching the most recently
 407   // read value separately would be a win, but one would be
 408   // wrong.  When many threads are updating it, the cache
 409   // line it's in would bounce between caches, negating
 410   // any benefit.
 411 
 412   // In order to prevent race conditions do not load cache elements
 413   // repeatedly, but use a local copy:
 414   PcDesc* res;
 415 
 416   // Step one:  Check the most recently added value.
 417   res = _pc_descs[0];
 418   assert(res != nullptr, "PcDesc cache should be initialized already");
 419 
 420   // Approximate only here since PcDescContainer::find_pc_desc() checked for exact case.
 421   if (approximate && match_desc(res, pc_offset, approximate)) {
 422     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
 423     return res;
 424   }
 425 
 426   // Step two:  Check the rest of the LRU cache.
 427   for (int i = 1; i < cache_size; ++i) {
 428     res = _pc_descs[i];
 429     if (res->pc_offset() < 0) break;  // optimization: skip empty cache
 430     if (match_desc(res, pc_offset, approximate)) {
 431       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
 432       return res;
 433     }
 434   }
 435 
 436   // Report failure.
 437   return nullptr;
 438 }
 439 
 440 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
 441   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
 442   // Update the LRU cache by shifting pc_desc forward.
 443   for (int i = 0; i < cache_size; i++)  {
 444     PcDesc* next = _pc_descs[i];
 445     _pc_descs[i] = pc_desc;
 446     pc_desc = next;
 447   }
 448 }
 449 
 450 // adjust pcs_size so that it is a multiple of both oopSize and
 451 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
 452 // of oopSize, then 2*sizeof(PcDesc) is)
 453 static int adjust_pcs_size(int pcs_size) {
 454   int nsize = align_up(pcs_size,   oopSize);
 455   if ((nsize % sizeof(PcDesc)) != 0) {
 456     nsize = pcs_size + sizeof(PcDesc);
 457   }
 458   assert((nsize % oopSize) == 0, "correct alignment");
 459   return nsize;
 460 }
 461 
 462 bool nmethod::is_method_handle_return(address return_pc) {
 463   if (!has_method_handle_invokes())  return false;
 464   PcDesc* pd = pc_desc_at(return_pc);
 465   if (pd == nullptr)
 466     return false;
 467   return pd->is_method_handle_invoke();
 468 }
 469 
 470 // Returns a string version of the method state.
 471 const char* nmethod::state() const {
 472   int state = get_state();
 473   switch (state) {
 474   case not_installed:
 475     return "not installed";
 476   case in_use:
 477     return "in use";
 478   case not_entrant:
 479     return "not_entrant";
 480   default:
 481     fatal("unexpected method state: %d", state);
 482     return nullptr;
 483   }
 484 }
 485 
 486 void nmethod::set_deoptimized_done() {
 487   ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
 488   if (_deoptimization_status != deoptimize_done) { // can't go backwards
 489     Atomic::store(&_deoptimization_status, deoptimize_done);
 490   }
 491 }
 492 
 493 ExceptionCache* nmethod::exception_cache_acquire() const {
 494   return Atomic::load_acquire(&_exception_cache);
 495 }
 496 
 497 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
 498   assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
 499   assert(new_entry != nullptr,"Must be non null");
 500   assert(new_entry->next() == nullptr, "Must be null");
 501 
 502   for (;;) {
 503     ExceptionCache *ec = exception_cache();
 504     if (ec != nullptr) {
 505       Klass* ex_klass = ec->exception_type();
 506       if (!ex_klass->is_loader_alive()) {
 507         // We must guarantee that entries are not inserted with new next pointer
 508         // edges to ExceptionCache entries with dead klasses, due to bad interactions
 509         // with concurrent ExceptionCache cleanup. Therefore, the inserts roll
 510         // the head pointer forward to the first live ExceptionCache, so that the new
 511         // next pointers always point at live ExceptionCaches, that are not removed due
 512         // to concurrent ExceptionCache cleanup.
 513         ExceptionCache* next = ec->next();
 514         if (Atomic::cmpxchg(&_exception_cache, ec, next) == ec) {
 515           CodeCache::release_exception_cache(ec);
 516         }
 517         continue;
 518       }
 519       ec = exception_cache();
 520       if (ec != nullptr) {
 521         new_entry->set_next(ec);
 522       }
 523     }
 524     if (Atomic::cmpxchg(&_exception_cache, ec, new_entry) == ec) {
 525       return;
 526     }
 527   }
 528 }
 529 
 530 void nmethod::clean_exception_cache() {
 531   // For each nmethod, only a single thread may call this cleanup function
 532   // at the same time, whether called in STW cleanup or concurrent cleanup.
 533   // Note that if the GC is processing exception cache cleaning in a concurrent phase,
 534   // then a single writer may contend with cleaning up the head pointer to the
 535   // first ExceptionCache node that has a Klass* that is alive. That is fine,
 536   // as long as there is no concurrent cleanup of next pointers from concurrent writers.
 537   // And the concurrent writers do not clean up next pointers, only the head.
 538   // Also note that concurrent readers will walk through Klass* pointers that are not
 539   // alive. That does not cause ABA problems, because Klass* is deleted after
 540   // a handshake with all threads, after all stale ExceptionCaches have been
 541   // unlinked. That is also when the CodeCache::exception_cache_purge_list()
 542   // is deleted, with all ExceptionCache entries that were cleaned concurrently.
 543   // That similarly implies that CAS operations on ExceptionCache entries do not
 544   // suffer from ABA problems as unlinking and deletion is separated by a global
 545   // handshake operation.
 546   ExceptionCache* prev = nullptr;
 547   ExceptionCache* curr = exception_cache_acquire();
 548 
 549   while (curr != nullptr) {
 550     ExceptionCache* next = curr->next();
 551 
 552     if (!curr->exception_type()->is_loader_alive()) {
 553       if (prev == nullptr) {
 554         // Try to clean head; this is contended by concurrent inserts, that
 555         // both lazily clean the head, and insert entries at the head. If
 556         // the CAS fails, the operation is restarted.
 557         if (Atomic::cmpxchg(&_exception_cache, curr, next) != curr) {
 558           prev = nullptr;
 559           curr = exception_cache_acquire();
 560           continue;
 561         }
 562       } else {
 563         // It is impossible to during cleanup connect the next pointer to
 564         // an ExceptionCache that has not been published before a safepoint
 565         // prior to the cleanup. Therefore, release is not required.
 566         prev->set_next(next);
 567       }
 568       // prev stays the same.
 569 
 570       CodeCache::release_exception_cache(curr);
 571     } else {
 572       prev = curr;
 573     }
 574 
 575     curr = next;
 576   }
 577 }
 578 
 579 // public method for accessing the exception cache
 580 // These are the public access methods.
 581 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
 582   // We never grab a lock to read the exception cache, so we may
 583   // have false negatives. This is okay, as it can only happen during
 584   // the first few exception lookups for a given nmethod.
 585   ExceptionCache* ec = exception_cache_acquire();
 586   while (ec != nullptr) {
 587     address ret_val;
 588     if ((ret_val = ec->match(exception,pc)) != nullptr) {
 589       return ret_val;
 590     }
 591     ec = ec->next();
 592   }
 593   return nullptr;
 594 }
 595 
 596 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
 597   // There are potential race conditions during exception cache updates, so we
 598   // must own the ExceptionCache_lock before doing ANY modifications. Because
 599   // we don't lock during reads, it is possible to have several threads attempt
 600   // to update the cache with the same data. We need to check for already inserted
 601   // copies of the current data before adding it.
 602 
 603   MutexLocker ml(ExceptionCache_lock);
 604   ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
 605 
 606   if (target_entry == nullptr || !target_entry->add_address_and_handler(pc,handler)) {
 607     target_entry = new ExceptionCache(exception,pc,handler);
 608     add_exception_cache_entry(target_entry);
 609   }
 610 }
 611 
 612 // private method for handling exception cache
 613 // These methods are private, and used to manipulate the exception cache
 614 // directly.
 615 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
 616   ExceptionCache* ec = exception_cache_acquire();
 617   while (ec != nullptr) {
 618     if (ec->match_exception_with_space(exception)) {
 619       return ec;
 620     }
 621     ec = ec->next();
 622   }
 623   return nullptr;
 624 }
 625 
 626 bool nmethod::is_at_poll_return(address pc) {
 627   RelocIterator iter(this, pc, pc+1);
 628   while (iter.next()) {
 629     if (iter.type() == relocInfo::poll_return_type)
 630       return true;
 631   }
 632   return false;
 633 }
 634 
 635 
 636 bool nmethod::is_at_poll_or_poll_return(address pc) {
 637   RelocIterator iter(this, pc, pc+1);
 638   while (iter.next()) {
 639     relocInfo::relocType t = iter.type();
 640     if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
 641       return true;
 642   }
 643   return false;
 644 }
 645 
 646 void nmethod::verify_oop_relocations() {
 647   // Ensure sure that the code matches the current oop values
 648   RelocIterator iter(this, nullptr, nullptr);
 649   while (iter.next()) {
 650     if (iter.type() == relocInfo::oop_type) {
 651       oop_Relocation* reloc = iter.oop_reloc();
 652       if (!reloc->oop_is_immediate()) {
 653         reloc->verify_oop_relocation();
 654       }
 655     }
 656   }
 657 }
 658 
 659 
 660 ScopeDesc* nmethod::scope_desc_at(address pc) {
 661   PcDesc* pd = pc_desc_at(pc);
 662   guarantee(pd != nullptr, "scope must be present");
 663   return new ScopeDesc(this, pd);
 664 }
 665 
 666 ScopeDesc* nmethod::scope_desc_near(address pc) {
 667   PcDesc* pd = pc_desc_near(pc);
 668   guarantee(pd != nullptr, "scope must be present");
 669   return new ScopeDesc(this, pd);
 670 }
 671 
 672 address nmethod::oops_reloc_begin() const {
 673   // If the method is not entrant then a JMP is plastered over the
 674   // first few bytes.  If an oop in the old code was there, that oop
 675   // should not get GC'd.  Skip the first few bytes of oops on
 676   // not-entrant methods.
 677   if (frame_complete_offset() != CodeOffsets::frame_never_safe &&
 678       code_begin() + frame_complete_offset() >
 679       verified_entry_point() + NativeJump::instruction_size)
 680   {
 681     // If we have a frame_complete_offset after the native jump, then there
 682     // is no point trying to look for oops before that. This is a requirement
 683     // for being allowed to scan oops concurrently.
 684     return code_begin() + frame_complete_offset();
 685   }
 686 
 687   // It is not safe to read oops concurrently using entry barriers, if their
 688   // location depend on whether the nmethod is entrant or not.
 689   // assert(BarrierSet::barrier_set()->barrier_set_nmethod() == nullptr, "Not safe oop scan");
 690 
 691   address low_boundary = verified_entry_point();
 692   if (!is_in_use()) {
 693     low_boundary += NativeJump::instruction_size;
 694     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
 695     // This means that the low_boundary is going to be a little too high.
 696     // This shouldn't matter, since oops of non-entrant methods are never used.
 697     // In fact, why are we bothering to look at oops in a non-entrant method??
 698   }
 699   return low_boundary;
 700 }
 701 
 702 // Method that knows how to preserve outgoing arguments at call. This method must be
 703 // called with a frame corresponding to a Java invoke
 704 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
 705   if (method() == nullptr) {
 706     return;
 707   }
 708 
 709   // handle the case of an anchor explicitly set in continuation code that doesn't have a callee
 710   JavaThread* thread = reg_map->thread();
 711   if (thread->has_last_Java_frame() && fr.sp() == thread->last_Java_sp()) {
 712     return;
 713   }
 714 
 715   if (!method()->is_native()) {
 716     address pc = fr.pc();
 717     bool has_receiver, has_appendix;
 718     Symbol* signature;
 719 
 720     // The method attached by JIT-compilers should be used, if present.
 721     // Bytecode can be inaccurate in such case.
 722     Method* callee = attached_method_before_pc(pc);
 723     if (callee != nullptr) {
 724       has_receiver = !(callee->access_flags().is_static());
 725       has_appendix = false;
 726       signature    = callee->signature();
 727 
 728       // If inline types are passed as fields, use the extended signature
 729       // which contains the types of all (oop) fields of the inline type.
 730       if (is_compiled_by_c2() && callee->has_scalarized_args()) {
 731         const GrowableArray<SigEntry>* sig = callee->adapter()->get_sig_cc();
 732         assert(sig != nullptr, "sig should never be null");
 733         TempNewSymbol tmp_sig = SigEntry::create_symbol(sig);
 734         has_receiver = false; // The extended signature contains the receiver type
 735         fr.oops_compiled_arguments_do(tmp_sig, has_receiver, has_appendix, reg_map, f);
 736         return;
 737       }
 738     } else {
 739       SimpleScopeDesc ssd(this, pc);
 740 
 741       Bytecode_invoke call(methodHandle(Thread::current(), ssd.method()), ssd.bci());
 742       has_receiver = call.has_receiver();
 743       has_appendix = call.has_appendix();
 744       signature    = call.signature();
 745     }
 746 
 747     fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
 748   } else if (method()->is_continuation_enter_intrinsic()) {
 749     // This method only calls Continuation.enter()
 750     Symbol* signature = vmSymbols::continuationEnter_signature();
 751     fr.oops_compiled_arguments_do(signature, false, false, reg_map, f);
 752   }
 753 }
 754 
 755 Method* nmethod::attached_method(address call_instr) {
 756   assert(code_contains(call_instr), "not part of the nmethod");
 757   RelocIterator iter(this, call_instr, call_instr + 1);
 758   while (iter.next()) {
 759     if (iter.addr() == call_instr) {
 760       switch(iter.type()) {
 761         case relocInfo::static_call_type:      return iter.static_call_reloc()->method_value();
 762         case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
 763         case relocInfo::virtual_call_type:     return iter.virtual_call_reloc()->method_value();
 764         default:                               break;
 765       }
 766     }
 767   }
 768   return nullptr; // not found
 769 }
 770 
 771 Method* nmethod::attached_method_before_pc(address pc) {
 772   if (NativeCall::is_call_before(pc)) {
 773     NativeCall* ncall = nativeCall_before(pc);
 774     return attached_method(ncall->instruction_address());
 775   }
 776   return nullptr; // not a call
 777 }
 778 
 779 void nmethod::clear_inline_caches() {
 780   assert(SafepointSynchronize::is_at_safepoint(), "clearing of IC's only allowed at safepoint");
 781   RelocIterator iter(this);
 782   while (iter.next()) {
 783     iter.reloc()->clear_inline_cache();
 784   }
 785 }
 786 
 787 #ifdef ASSERT
 788 // Check class_loader is alive for this bit of metadata.
 789 class CheckClass : public MetadataClosure {
 790   void do_metadata(Metadata* md) {
 791     Klass* klass = nullptr;
 792     if (md->is_klass()) {
 793       klass = ((Klass*)md);
 794     } else if (md->is_method()) {
 795       klass = ((Method*)md)->method_holder();
 796     } else if (md->is_methodData()) {
 797       klass = ((MethodData*)md)->method()->method_holder();
 798     } else {
 799       md->print();
 800       ShouldNotReachHere();
 801     }
 802     assert(klass->is_loader_alive(), "must be alive");
 803   }
 804 };
 805 #endif // ASSERT
 806 
 807 
 808 static void clean_ic_if_metadata_is_dead(CompiledIC *ic) {
 809   ic->clean_metadata();
 810 }
 811 
 812 // Clean references to unloaded nmethods at addr from this one, which is not unloaded.
 813 template <typename CallsiteT>
 814 static void clean_if_nmethod_is_unloaded(CallsiteT* callsite, nmethod* from,
 815                                          bool clean_all) {
 816   CodeBlob* cb = CodeCache::find_blob(callsite->destination());
 817   if (!cb->is_nmethod()) {
 818     return;
 819   }
 820   nmethod* nm = cb->as_nmethod();
 821   if (clean_all || !nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
 822     callsite->set_to_clean();
 823   }
 824 }
 825 
 826 // Cleans caches in nmethods that point to either classes that are unloaded
 827 // or nmethods that are unloaded.
 828 //
 829 // Can be called either in parallel by G1 currently or after all
 830 // nmethods are unloaded.  Return postponed=true in the parallel case for
 831 // inline caches found that point to nmethods that are not yet visited during
 832 // the do_unloading walk.
 833 void nmethod::unload_nmethod_caches(bool unloading_occurred) {
 834   ResourceMark rm;
 835 
 836   // Exception cache only needs to be called if unloading occurred
 837   if (unloading_occurred) {
 838     clean_exception_cache();
 839   }
 840 
 841   cleanup_inline_caches_impl(unloading_occurred, false);
 842 
 843 #ifdef ASSERT
 844   // Check that the metadata embedded in the nmethod is alive
 845   CheckClass check_class;
 846   metadata_do(&check_class);
 847 #endif
 848 }
 849 
 850 void nmethod::run_nmethod_entry_barrier() {
 851   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
 852   if (bs_nm != nullptr) {
 853     // We want to keep an invariant that nmethods found through iterations of a Thread's
 854     // nmethods found in safepoints have gone through an entry barrier and are not armed.
 855     // By calling this nmethod entry barrier, it plays along and acts
 856     // like any other nmethod found on the stack of a thread (fewer surprises).
 857     nmethod* nm = this;
 858     bool alive = bs_nm->nmethod_entry_barrier(nm);
 859     assert(alive, "should be alive");
 860   }
 861 }
 862 
 863 // Only called by whitebox test
 864 void nmethod::cleanup_inline_caches_whitebox() {
 865   assert_locked_or_safepoint(CodeCache_lock);
 866   CompiledICLocker ic_locker(this);
 867   cleanup_inline_caches_impl(false /* unloading_occurred */, true /* clean_all */);
 868 }
 869 
 870 address* nmethod::orig_pc_addr(const frame* fr) {
 871   return (address*) ((address)fr->unextended_sp() + orig_pc_offset());
 872 }
 873 
 874 // Called to clean up after class unloading for live nmethods
 875 void nmethod::cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all) {
 876   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
 877   ResourceMark rm;
 878 
 879   // Find all calls in an nmethod and clear the ones that point to bad nmethods.
 880   RelocIterator iter(this, oops_reloc_begin());
 881   bool is_in_static_stub = false;
 882   while(iter.next()) {
 883 
 884     switch (iter.type()) {
 885 
 886     case relocInfo::virtual_call_type:
 887       if (unloading_occurred) {
 888         // If class unloading occurred we first clear ICs where the cached metadata
 889         // is referring to an unloaded klass or method.
 890         clean_ic_if_metadata_is_dead(CompiledIC_at(&iter));
 891       }
 892 
 893       clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), this, clean_all);
 894       break;
 895 
 896     case relocInfo::opt_virtual_call_type:
 897     case relocInfo::static_call_type:
 898       clean_if_nmethod_is_unloaded(CompiledDirectCall::at(iter.reloc()), this, clean_all);
 899       break;
 900 
 901     case relocInfo::static_stub_type: {
 902       is_in_static_stub = true;
 903       break;
 904     }
 905 
 906     case relocInfo::metadata_type: {
 907       // Only the metadata relocations contained in static/opt virtual call stubs
 908       // contains the Method* passed to c2i adapters. It is the only metadata
 909       // relocation that needs to be walked, as it is the one metadata relocation
 910       // that violates the invariant that all metadata relocations have an oop
 911       // in the compiled method (due to deferred resolution and code patching).
 912 
 913       // This causes dead metadata to remain in compiled methods that are not
 914       // unloading. Unless these slippery metadata relocations of the static
 915       // stubs are at least cleared, subsequent class redefinition operations
 916       // will access potentially free memory, and JavaThread execution
 917       // concurrent to class unloading may call c2i adapters with dead methods.
 918       if (!is_in_static_stub) {
 919         // The first metadata relocation after a static stub relocation is the
 920         // metadata relocation of the static stub used to pass the Method* to
 921         // c2i adapters.
 922         continue;
 923       }
 924       is_in_static_stub = false;
 925       if (is_unloading()) {
 926         // If the nmethod itself is dying, then it may point at dead metadata.
 927         // Nobody should follow that metadata; it is strictly unsafe.
 928         continue;
 929       }
 930       metadata_Relocation* r = iter.metadata_reloc();
 931       Metadata* md = r->metadata_value();
 932       if (md != nullptr && md->is_method()) {
 933         Method* method = static_cast<Method*>(md);
 934         if (!method->method_holder()->is_loader_alive()) {
 935           Atomic::store(r->metadata_addr(), (Method*)nullptr);
 936 
 937           if (!r->metadata_is_immediate()) {
 938             r->fix_metadata_relocation();
 939           }
 940         }
 941       }
 942       break;
 943     }
 944 
 945     default:
 946       break;
 947     }
 948   }
 949 }
 950 
 951 address nmethod::continuation_for_implicit_exception(address pc, bool for_div0_check) {
 952   // Exception happened outside inline-cache check code => we are inside
 953   // an active nmethod => use cpc to determine a return address
 954   int exception_offset = int(pc - code_begin());
 955   int cont_offset = ImplicitExceptionTable(this).continuation_offset( exception_offset );
 956 #ifdef ASSERT
 957   if (cont_offset == 0) {
 958     Thread* thread = Thread::current();
 959     ResourceMark rm(thread);
 960     CodeBlob* cb = CodeCache::find_blob(pc);
 961     assert(cb != nullptr && cb == this, "");
 962 
 963     // Keep tty output consistent. To avoid ttyLocker, we buffer in stream, and print all at once.
 964     stringStream ss;
 965     ss.print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
 966     print_on(&ss);
 967     method()->print_codes_on(&ss);
 968     print_code_on(&ss);
 969     print_pcs_on(&ss);
 970     tty->print("%s", ss.as_string()); // print all at once
 971   }
 972 #endif
 973   if (cont_offset == 0) {
 974     // Let the normal error handling report the exception
 975     return nullptr;
 976   }
 977   if (cont_offset == exception_offset) {
 978 #if INCLUDE_JVMCI
 979     Deoptimization::DeoptReason deopt_reason = for_div0_check ? Deoptimization::Reason_div0_check : Deoptimization::Reason_null_check;
 980     JavaThread *thread = JavaThread::current();
 981     thread->set_jvmci_implicit_exception_pc(pc);
 982     thread->set_pending_deoptimization(Deoptimization::make_trap_request(deopt_reason,
 983                                                                          Deoptimization::Action_reinterpret));
 984     return (SharedRuntime::deopt_blob()->implicit_exception_uncommon_trap());
 985 #else
 986     ShouldNotReachHere();
 987 #endif
 988   }
 989   return code_begin() + cont_offset;
 990 }
 991 
 992 class HasEvolDependency : public MetadataClosure {
 993   bool _has_evol_dependency;
 994  public:
 995   HasEvolDependency() : _has_evol_dependency(false) {}
 996   void do_metadata(Metadata* md) {
 997     if (md->is_method()) {
 998       Method* method = (Method*)md;
 999       if (method->is_old()) {
1000         _has_evol_dependency = true;
1001       }
1002     }
1003   }
1004   bool has_evol_dependency() const { return _has_evol_dependency; }
1005 };
1006 
1007 bool nmethod::has_evol_metadata() {
1008   // Check the metadata in relocIter and CompiledIC and also deoptimize
1009   // any nmethod that has reference to old methods.
1010   HasEvolDependency check_evol;
1011   metadata_do(&check_evol);
1012   if (check_evol.has_evol_dependency() && log_is_enabled(Debug, redefine, class, nmethod)) {
1013     ResourceMark rm;
1014     log_debug(redefine, class, nmethod)
1015             ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on in nmethod metadata",
1016              _method->method_holder()->external_name(),
1017              _method->name()->as_C_string(),
1018              _method->signature()->as_C_string(),
1019              compile_id());
1020   }
1021   return check_evol.has_evol_dependency();
1022 }
1023 
1024 int nmethod::total_size() const {
1025   return
1026     consts_size()        +
1027     insts_size()         +
1028     stub_size()          +
1029     scopes_data_size()   +
1030     scopes_pcs_size()    +
1031     handler_table_size() +
1032     nul_chk_table_size();
1033 }
1034 
1035 const char* nmethod::compile_kind() const {
1036   if (is_osr_method())     return "osr";
1037   if (method() != nullptr && is_native_method()) {
1038     if (method()->is_continuation_native_intrinsic()) {
1039       return "cnt";
1040     }
1041     return "c2n";
1042   }
1043   return nullptr;
1044 }
1045 
1046 const char* nmethod::compiler_name() const {
1047   return compilertype2name(_compiler_type);
1048 }
1049 
1050 #ifdef ASSERT
1051 class CheckForOopsClosure : public OopClosure {
1052   bool _found_oop = false;
1053  public:
1054   virtual void do_oop(oop* o) { _found_oop = true; }
1055   virtual void do_oop(narrowOop* o) { _found_oop = true; }
1056   bool found_oop() { return _found_oop; }
1057 };
1058 class CheckForMetadataClosure : public MetadataClosure {
1059   bool _found_metadata = false;
1060   Metadata* _ignore = nullptr;
1061  public:
1062   CheckForMetadataClosure(Metadata* ignore) : _ignore(ignore) {}
1063   virtual void do_metadata(Metadata* md) { if (md != _ignore) _found_metadata = true; }
1064   bool found_metadata() { return _found_metadata; }
1065 };
1066 
1067 static void assert_no_oops_or_metadata(nmethod* nm) {
1068   if (nm == nullptr) return;
1069   assert(nm->oop_maps() == nullptr, "expectation");
1070 
1071   CheckForOopsClosure cfo;
1072   nm->oops_do(&cfo);
1073   assert(!cfo.found_oop(), "no oops allowed");
1074 
1075   // We allow an exception for the own Method, but require its class to be permanent.
1076   Method* own_method = nm->method();
1077   CheckForMetadataClosure cfm(/* ignore reference to own Method */ own_method);
1078   nm->metadata_do(&cfm);
1079   assert(!cfm.found_metadata(), "no metadata allowed");
1080 
1081   assert(own_method->method_holder()->class_loader_data()->is_permanent_class_loader_data(),
1082          "Method's class needs to be permanent");
1083 }
1084 #endif
1085 
1086 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
1087   int compile_id,
1088   CodeBuffer *code_buffer,
1089   int vep_offset,
1090   int frame_complete,
1091   int frame_size,
1092   ByteSize basic_lock_owner_sp_offset,
1093   ByteSize basic_lock_sp_offset,
1094   OopMapSet* oop_maps,
1095   int exception_handler) {
1096   code_buffer->finalize_oop_references(method);
1097   // create nmethod
1098   nmethod* nm = nullptr;
1099   int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1100   {
1101     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1102 
1103     CodeOffsets offsets;
1104     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
1105     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
1106     if (exception_handler != -1) {
1107       offsets.set_value(CodeOffsets::Exceptions, exception_handler);
1108     }
1109 
1110     // MH intrinsics are dispatch stubs which are compatible with NonNMethod space.
1111     // IsUnloadingBehaviour::is_unloading needs to handle them separately.
1112     bool allow_NonNMethod_space = method->can_be_allocated_in_NonNMethod_space();
1113     nm = new (native_nmethod_size, allow_NonNMethod_space)
1114     nmethod(method(), compiler_none, native_nmethod_size,
1115             compile_id, &offsets,
1116             code_buffer, frame_size,
1117             basic_lock_owner_sp_offset,
1118             basic_lock_sp_offset,
1119             oop_maps);
1120     DEBUG_ONLY( if (allow_NonNMethod_space) assert_no_oops_or_metadata(nm); )
1121     NOT_PRODUCT(if (nm != nullptr) native_nmethod_stats.note_native_nmethod(nm));
1122   }
1123 
1124   if (nm != nullptr) {
1125     // verify nmethod
1126     debug_only(nm->verify();) // might block
1127 
1128     nm->log_new_nmethod();
1129   }
1130   return nm;
1131 }
1132 
1133 nmethod* nmethod::new_nmethod(const methodHandle& method,
1134   int compile_id,
1135   int entry_bci,
1136   CodeOffsets* offsets,
1137   int orig_pc_offset,
1138   DebugInformationRecorder* debug_info,
1139   Dependencies* dependencies,
1140   CodeBuffer* code_buffer, int frame_size,
1141   OopMapSet* oop_maps,
1142   ExceptionHandlerTable* handler_table,
1143   ImplicitExceptionTable* nul_chk_table,
1144   AbstractCompiler* compiler,
1145   CompLevel comp_level
1146 #if INCLUDE_JVMCI
1147   , char* speculations,
1148   int speculations_len,
1149   JVMCINMethodData* jvmci_data
1150 #endif
1151 )
1152 {
1153   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1154   code_buffer->finalize_oop_references(method);
1155   // create nmethod
1156   nmethod* nm = nullptr;
1157   int nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1158 #if INCLUDE_JVMCI
1159     if (compiler->is_jvmci()) {
1160       nmethod_size += align_up(jvmci_data->size(), oopSize);
1161     }
1162 #endif
1163 
1164   int immutable_data_size =
1165       adjust_pcs_size(debug_info->pcs_size())
1166     + align_up((int)dependencies->size_in_bytes(), oopSize)
1167     + align_up(handler_table->size_in_bytes()    , oopSize)
1168     + align_up(nul_chk_table->size_in_bytes()    , oopSize)
1169 #if INCLUDE_JVMCI
1170     + align_up(speculations_len                  , oopSize)
1171 #endif
1172     + align_up(debug_info->data_size()           , oopSize);
1173 
1174   // First, allocate space for immutable data in C heap.
1175   address immutable_data = nullptr;
1176   if (immutable_data_size > 0) {
1177     immutable_data = (address)os::malloc(immutable_data_size, mtCode);
1178     if (immutable_data == nullptr) {
1179       vm_exit_out_of_memory(immutable_data_size, OOM_MALLOC_ERROR, "nmethod: no space for immutable data");
1180       return nullptr;
1181     }
1182   }
1183   {
1184     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1185 
1186     nm = new (nmethod_size, comp_level)
1187     nmethod(method(), compiler->type(), nmethod_size, immutable_data_size,
1188             compile_id, entry_bci, immutable_data, offsets, orig_pc_offset,
1189             debug_info, dependencies, code_buffer, frame_size, oop_maps,
1190             handler_table, nul_chk_table, compiler, comp_level
1191 #if INCLUDE_JVMCI
1192             , speculations,
1193             speculations_len,
1194             jvmci_data
1195 #endif
1196             );
1197 
1198     if (nm != nullptr) {
1199       // To make dependency checking during class loading fast, record
1200       // the nmethod dependencies in the classes it is dependent on.
1201       // This allows the dependency checking code to simply walk the
1202       // class hierarchy above the loaded class, checking only nmethods
1203       // which are dependent on those classes.  The slow way is to
1204       // check every nmethod for dependencies which makes it linear in
1205       // the number of methods compiled.  For applications with a lot
1206       // classes the slow way is too slow.
1207       for (Dependencies::DepStream deps(nm); deps.next(); ) {
1208         if (deps.type() == Dependencies::call_site_target_value) {
1209           // CallSite dependencies are managed on per-CallSite instance basis.
1210           oop call_site = deps.argument_oop(0);
1211           MethodHandles::add_dependent_nmethod(call_site, nm);
1212         } else {
1213           InstanceKlass* ik = deps.context_type();
1214           if (ik == nullptr) {
1215             continue;  // ignore things like evol_method
1216           }
1217           // record this nmethod as dependent on this klass
1218           ik->add_dependent_nmethod(nm);
1219         }
1220       }
1221       NOT_PRODUCT(if (nm != nullptr)  note_java_nmethod(nm));
1222     }
1223   }
1224   // Do verification and logging outside CodeCache_lock.
1225   if (nm != nullptr) {
1226     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
1227     DEBUG_ONLY(nm->verify();)
1228     nm->log_new_nmethod();
1229   }
1230   return nm;
1231 }
1232 
1233 // Fill in default values for various fields
1234 void nmethod::init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets) {
1235   // avoid uninitialized fields, even for short time periods
1236   _exception_cache            = nullptr;
1237   _gc_data                    = nullptr;
1238   _oops_do_mark_link          = nullptr;
1239   _compiled_ic_data           = nullptr;
1240 
1241   _is_unloading_state         = 0;
1242   _state                      = not_installed;
1243 
1244   _has_unsafe_access          = 0;
1245   _has_method_handle_invokes  = 0;
1246   _has_wide_vectors           = 0;
1247   _has_monitors               = 0;
1248   _has_scoped_access          = 0;
1249   _has_flushed_dependencies   = 0;
1250   _is_unlinked                = 0;
1251   _load_reported              = 0; // jvmti state
1252 
1253   _deoptimization_status      = not_marked;
1254 
1255   // SECT_CONSTS is first in code buffer so the offset should be 0.
1256   int consts_offset = code_buffer->total_offset_of(code_buffer->consts());
1257   assert(consts_offset == 0, "const_offset: %d", consts_offset);
1258 
1259   _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
1260 
1261   CHECKED_CAST(_entry_offset,              uint16_t, (offsets->value(CodeOffsets::Entry)));
1262   CHECKED_CAST(_verified_entry_offset,     uint16_t, (offsets->value(CodeOffsets::Verified_Entry)));
1263 
1264   _inline_entry_point             = entry_point();
1265   _verified_inline_entry_point    = verified_entry_point();
1266   _verified_inline_ro_entry_point = verified_entry_point();
1267 
1268   _skipped_instructions_size = code_buffer->total_skipped_instructions_size();
1269 }
1270 
1271 // Post initialization
1272 void nmethod::post_init() {
1273   clear_unloading_state();
1274 
1275   finalize_relocations();
1276 
1277   Universe::heap()->register_nmethod(this);
1278   debug_only(Universe::heap()->verify_nmethod(this));
1279 
1280   CodeCache::commit(this);
1281 }
1282 
1283 // For native wrappers
1284 nmethod::nmethod(
1285   Method* method,
1286   CompilerType type,
1287   int nmethod_size,
1288   int compile_id,
1289   CodeOffsets* offsets,
1290   CodeBuffer* code_buffer,
1291   int frame_size,
1292   ByteSize basic_lock_owner_sp_offset,
1293   ByteSize basic_lock_sp_offset,
1294   OopMapSet* oop_maps )
1295   : CodeBlob("native nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1296              offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
1297   _deoptimization_generation(0),
1298   _gc_epoch(CodeCache::gc_epoch()),
1299   _method(method),
1300   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
1301   _native_basic_lock_sp_offset(basic_lock_sp_offset)
1302 {
1303   {
1304     debug_only(NoSafepointVerifier nsv;)
1305     assert_locked_or_safepoint(CodeCache_lock);
1306     assert(!method->has_scalarized_args(), "scalarized native wrappers not supported yet");
1307     init_defaults(code_buffer, offsets);
1308 
1309     _osr_entry_point         = nullptr;
1310     _pc_desc_container       = nullptr;
1311     _entry_bci               = InvocationEntryBci;
1312     _compile_id              = compile_id;
1313     _comp_level              = CompLevel_none;
1314     _compiler_type           = type;
1315     _orig_pc_offset          = 0;
1316     _num_stack_arg_slots     = _method->constMethod()->num_stack_arg_slots();
1317 
1318     if (offsets->value(CodeOffsets::Exceptions) != -1) {
1319       // Continuation enter intrinsic
1320       _exception_offset      = code_offset() + offsets->value(CodeOffsets::Exceptions);
1321     } else {
1322       _exception_offset      = 0;
1323     }
1324     // Native wrappers do not have deopt handlers. Make the values
1325     // something that will never match a pc like the nmethod vtable entry
1326     _deopt_handler_offset    = 0;
1327     _deopt_mh_handler_offset = 0;
1328     _unwind_handler_offset   = 0;
1329 
1330     CHECKED_CAST(_metadata_offset, uint16_t, (align_up(code_buffer->total_oop_size(), oopSize)));
1331     int data_end_offset = _metadata_offset + align_up(code_buffer->total_metadata_size(), wordSize);
1332 #if INCLUDE_JVMCI
1333     // jvmci_data_size is 0 in native wrapper but we need to set offset
1334     // to correctly calculate metadata_end address
1335     CHECKED_CAST(_jvmci_data_offset, uint16_t, data_end_offset);
1336 #endif
1337     assert((data_offset() + data_end_offset) <= nmethod_size, "wrong nmethod's size: %d < %d", nmethod_size, (data_offset() + data_end_offset));
1338 
1339     // native wrapper does not have read-only data but we need unique not null address
1340     _immutable_data          = data_end();
1341     _immutable_data_size     = 0;
1342     _nul_chk_table_offset    = 0;
1343     _handler_table_offset    = 0;
1344     _scopes_pcs_offset       = 0;
1345     _scopes_data_offset      = 0;
1346 #if INCLUDE_JVMCI
1347     _speculations_offset     = 0;
1348 #endif
1349 
1350     code_buffer->copy_code_and_locs_to(this);
1351     code_buffer->copy_values_to(this);
1352 
1353     post_init();
1354   }
1355 
1356   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
1357     ttyLocker ttyl;  // keep the following output all in one block
1358     // This output goes directly to the tty, not the compiler log.
1359     // To enable tools to match it up with the compilation activity,
1360     // be sure to tag this tty output with the compile ID.
1361     if (xtty != nullptr) {
1362       xtty->begin_head("print_native_nmethod");
1363       xtty->method(_method);
1364       xtty->stamp();
1365       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
1366     }
1367     // Print the header part, then print the requested information.
1368     // This is both handled in decode2(), called via print_code() -> decode()
1369     if (PrintNativeNMethods) {
1370       tty->print_cr("-------------------------- Assembly (native nmethod) ---------------------------");
1371       print_code();
1372       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1373 #if defined(SUPPORT_DATA_STRUCTS)
1374       if (AbstractDisassembler::show_structs()) {
1375         if (oop_maps != nullptr) {
1376           tty->print("oop maps:"); // oop_maps->print_on(tty) outputs a cr() at the beginning
1377           oop_maps->print_on(tty);
1378           tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1379         }
1380       }
1381 #endif
1382     } else {
1383       print(); // print the header part only.
1384     }
1385 #if defined(SUPPORT_DATA_STRUCTS)
1386     if (AbstractDisassembler::show_structs()) {
1387       if (PrintRelocations) {
1388         print_relocations();
1389         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1390       }
1391     }
1392 #endif
1393     if (xtty != nullptr) {
1394       xtty->tail("print_native_nmethod");
1395     }
1396   }
1397 }
1398 
1399 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
1400   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
1401 }
1402 
1403 void* nmethod::operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw () {
1404   // Try MethodNonProfiled and MethodProfiled.
1405   void* return_value = CodeCache::allocate(nmethod_size, CodeBlobType::MethodNonProfiled);
1406   if (return_value != nullptr || !allow_NonNMethod_space) return return_value;
1407   // Try NonNMethod or give up.
1408   return CodeCache::allocate(nmethod_size, CodeBlobType::NonNMethod);
1409 }
1410 
1411 // For normal JIT compiled code
1412 nmethod::nmethod(
1413   Method* method,
1414   CompilerType type,
1415   int nmethod_size,
1416   int immutable_data_size,
1417   int compile_id,
1418   int entry_bci,
1419   address immutable_data,
1420   CodeOffsets* offsets,
1421   int orig_pc_offset,
1422   DebugInformationRecorder* debug_info,
1423   Dependencies* dependencies,
1424   CodeBuffer *code_buffer,
1425   int frame_size,
1426   OopMapSet* oop_maps,
1427   ExceptionHandlerTable* handler_table,
1428   ImplicitExceptionTable* nul_chk_table,
1429   AbstractCompiler* compiler,
1430   CompLevel comp_level
1431 #if INCLUDE_JVMCI
1432   , char* speculations,
1433   int speculations_len,
1434   JVMCINMethodData* jvmci_data
1435 #endif
1436   )
1437   : CodeBlob("nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1438              offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
1439   _deoptimization_generation(0),
1440   _gc_epoch(CodeCache::gc_epoch()),
1441   _method(method),
1442   _osr_link(nullptr)
1443 {
1444   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1445   {
1446     debug_only(NoSafepointVerifier nsv;)
1447     assert_locked_or_safepoint(CodeCache_lock);
1448 
1449     init_defaults(code_buffer, offsets);
1450 
1451     _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
1452     _entry_bci       = entry_bci;
1453     _compile_id      = compile_id;
1454     _comp_level      = comp_level;
1455     _compiler_type   = type;
1456     _orig_pc_offset  = orig_pc_offset;
1457 
1458     _num_stack_arg_slots = entry_bci != InvocationEntryBci ? 0 : _method->constMethod()->num_stack_arg_slots();
1459 
1460     set_ctable_begin(header_begin() + content_offset());
1461 
1462 #if INCLUDE_JVMCI
1463     if (compiler->is_jvmci()) {
1464       // JVMCI might not produce any stub sections
1465       if (offsets->value(CodeOffsets::Exceptions) != -1) {
1466         _exception_offset        = code_offset() + offsets->value(CodeOffsets::Exceptions);
1467       } else {
1468         _exception_offset        = -1;
1469       }
1470       if (offsets->value(CodeOffsets::Deopt) != -1) {
1471         _deopt_handler_offset    = code_offset() + offsets->value(CodeOffsets::Deopt);
1472       } else {
1473         _deopt_handler_offset    = -1;
1474       }
1475       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
1476         _deopt_mh_handler_offset = code_offset() + offsets->value(CodeOffsets::DeoptMH);
1477       } else {
1478         _deopt_mh_handler_offset = -1;
1479       }
1480     } else
1481 #endif
1482     {
1483       // Exception handler and deopt handler are in the stub section
1484       assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
1485       assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
1486 
1487       _exception_offset          = _stub_offset + offsets->value(CodeOffsets::Exceptions);
1488       _deopt_handler_offset      = _stub_offset + offsets->value(CodeOffsets::Deopt);
1489       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
1490         _deopt_mh_handler_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
1491       } else {
1492         _deopt_mh_handler_offset = -1;
1493       }
1494     }
1495     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
1496       // C1 generates UnwindHandler at the end of instructions section.
1497       // Calculate positive offset as distance between the start of stubs section
1498       // (which is also the end of instructions section) and the start of the handler.
1499       int unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
1500       CHECKED_CAST(_unwind_handler_offset, int16_t, (_stub_offset - unwind_handler_offset));
1501     } else {
1502       _unwind_handler_offset = -1;
1503     }
1504     CHECKED_CAST(_metadata_offset, uint16_t, (align_up(code_buffer->total_oop_size(), oopSize)));
1505     int metadata_end_offset = _metadata_offset + align_up(code_buffer->total_metadata_size(), wordSize);
1506 
1507 #if INCLUDE_JVMCI
1508     CHECKED_CAST(_jvmci_data_offset, uint16_t, metadata_end_offset);
1509     int jvmci_data_size   = compiler->is_jvmci() ? jvmci_data->size() : 0;
1510     DEBUG_ONLY( int data_end_offset = _jvmci_data_offset  + align_up(jvmci_data_size, oopSize); )
1511 #else
1512     DEBUG_ONLY( int data_end_offset = metadata_end_offset; )
1513 #endif
1514     _inline_entry_point             = code_begin() + offsets->value(CodeOffsets::Inline_Entry);
1515     _verified_inline_entry_point    = code_begin() + offsets->value(CodeOffsets::Verified_Inline_Entry);
1516     _verified_inline_ro_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Inline_Entry_RO);
1517     assert((data_offset() + data_end_offset) <= nmethod_size, "wrong nmethod's size: %d > %d",
1518            (data_offset() + data_end_offset), nmethod_size);
1519 
1520     _immutable_data_size  = immutable_data_size;
1521     if (immutable_data_size > 0) {
1522       assert(immutable_data != nullptr, "required");
1523       _immutable_data     = immutable_data;
1524     } else {
1525       // We need unique not null address
1526       _immutable_data     = data_end();
1527     }
1528     CHECKED_CAST(_nul_chk_table_offset, uint16_t, (align_up((int)dependencies->size_in_bytes(), oopSize)));
1529     CHECKED_CAST(_handler_table_offset, uint16_t, (_nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize)));
1530     _scopes_pcs_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
1531     _scopes_data_offset   = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
1532 
1533 #if INCLUDE_JVMCI
1534     _speculations_offset  = _scopes_data_offset   + align_up(debug_info->data_size(), oopSize);
1535     DEBUG_ONLY( int immutable_data_end_offset = _speculations_offset  + align_up(speculations_len, oopSize); )
1536 #else
1537     DEBUG_ONLY( int immutable_data_end_offset = _scopes_data_offset + align_up(debug_info->data_size(), oopSize); )
1538 #endif
1539     assert(immutable_data_end_offset <= immutable_data_size, "wrong read-only data size: %d > %d",
1540            immutable_data_end_offset, immutable_data_size);
1541 
1542     // Copy code and relocation info
1543     code_buffer->copy_code_and_locs_to(this);
1544     // Copy oops and metadata
1545     code_buffer->copy_values_to(this);
1546     dependencies->copy_to(this);
1547     // Copy PcDesc and ScopeDesc data
1548     debug_info->copy_to(this);
1549 
1550     // Create cache after PcDesc data is copied - it will be used to initialize cache
1551     _pc_desc_container = new PcDescContainer(scopes_pcs_begin());
1552 
1553 #if INCLUDE_JVMCI
1554     if (compiler->is_jvmci()) {
1555       // Initialize the JVMCINMethodData object inlined into nm
1556       jvmci_nmethod_data()->copy(jvmci_data);
1557     }
1558 #endif
1559 
1560     // Copy contents of ExceptionHandlerTable to nmethod
1561     handler_table->copy_to(this);
1562     nul_chk_table->copy_to(this);
1563 
1564 #if INCLUDE_JVMCI
1565     // Copy speculations to nmethod
1566     if (speculations_size() != 0) {
1567       memcpy(speculations_begin(), speculations, speculations_len);
1568     }
1569 #endif
1570 
1571     post_init();
1572 
1573     // we use the information of entry points to find out if a method is
1574     // static or non static
1575     assert(compiler->is_c2() || compiler->is_jvmci() ||
1576            _method->is_static() == (entry_point() == verified_entry_point()),
1577            " entry points must be same for static methods and vice versa");
1578   }
1579 }
1580 
1581 // Print a short set of xml attributes to identify this nmethod.  The
1582 // output should be embedded in some other element.
1583 void nmethod::log_identity(xmlStream* log) const {
1584   log->print(" compile_id='%d'", compile_id());
1585   const char* nm_kind = compile_kind();
1586   if (nm_kind != nullptr)  log->print(" compile_kind='%s'", nm_kind);
1587   log->print(" compiler='%s'", compiler_name());
1588   if (TieredCompilation) {
1589     log->print(" level='%d'", comp_level());
1590   }
1591 #if INCLUDE_JVMCI
1592   if (jvmci_nmethod_data() != nullptr) {
1593     const char* jvmci_name = jvmci_nmethod_data()->name();
1594     if (jvmci_name != nullptr) {
1595       log->print(" jvmci_mirror_name='");
1596       log->text("%s", jvmci_name);
1597       log->print("'");
1598     }
1599   }
1600 #endif
1601 }
1602 
1603 
1604 #define LOG_OFFSET(log, name)                    \
1605   if (p2i(name##_end()) - p2i(name##_begin())) \
1606     log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'"    , \
1607                p2i(name##_begin()) - p2i(this))
1608 
1609 
1610 void nmethod::log_new_nmethod() const {
1611   if (LogCompilation && xtty != nullptr) {
1612     ttyLocker ttyl;
1613     xtty->begin_elem("nmethod");
1614     log_identity(xtty);
1615     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
1616     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
1617 
1618     LOG_OFFSET(xtty, relocation);
1619     LOG_OFFSET(xtty, consts);
1620     LOG_OFFSET(xtty, insts);
1621     LOG_OFFSET(xtty, stub);
1622     LOG_OFFSET(xtty, scopes_data);
1623     LOG_OFFSET(xtty, scopes_pcs);
1624     LOG_OFFSET(xtty, dependencies);
1625     LOG_OFFSET(xtty, handler_table);
1626     LOG_OFFSET(xtty, nul_chk_table);
1627     LOG_OFFSET(xtty, oops);
1628     LOG_OFFSET(xtty, metadata);
1629 
1630     xtty->method(method());
1631     xtty->stamp();
1632     xtty->end_elem();
1633   }
1634 }
1635 
1636 #undef LOG_OFFSET
1637 
1638 
1639 // Print out more verbose output usually for a newly created nmethod.
1640 void nmethod::print_on(outputStream* st, const char* msg) const {
1641   if (st != nullptr) {
1642     ttyLocker ttyl;
1643     if (WizardMode) {
1644       CompileTask::print(st, this, msg, /*short_form:*/ true);
1645       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
1646     } else {
1647       CompileTask::print(st, this, msg, /*short_form:*/ false);
1648     }
1649   }
1650 }
1651 
1652 void nmethod::maybe_print_nmethod(const DirectiveSet* directive) {
1653   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
1654   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
1655     print_nmethod(printnmethods);
1656   }
1657 }
1658 
1659 void nmethod::print_nmethod(bool printmethod) {
1660   ttyLocker ttyl;  // keep the following output all in one block
1661   if (xtty != nullptr) {
1662     xtty->begin_head("print_nmethod");
1663     log_identity(xtty);
1664     xtty->stamp();
1665     xtty->end_head();
1666   }
1667   // Print the header part, then print the requested information.
1668   // This is both handled in decode2().
1669   if (printmethod) {
1670     ResourceMark m;
1671     if (is_compiled_by_c1()) {
1672       tty->cr();
1673       tty->print_cr("============================= C1-compiled nmethod ==============================");
1674     }
1675     if (is_compiled_by_jvmci()) {
1676       tty->cr();
1677       tty->print_cr("=========================== JVMCI-compiled nmethod =============================");
1678     }
1679     tty->print_cr("----------------------------------- Assembly -----------------------------------");
1680     decode2(tty);
1681 #if defined(SUPPORT_DATA_STRUCTS)
1682     if (AbstractDisassembler::show_structs()) {
1683       // Print the oops from the underlying CodeBlob as well.
1684       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1685       print_oops(tty);
1686       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1687       print_metadata(tty);
1688       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1689       print_pcs_on(tty);
1690       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1691       if (oop_maps() != nullptr) {
1692         tty->print("oop maps:"); // oop_maps()->print_on(tty) outputs a cr() at the beginning
1693         oop_maps()->print_on(tty);
1694         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1695       }
1696     }
1697 #endif
1698   } else {
1699     print(); // print the header part only.
1700   }
1701 
1702 #if defined(SUPPORT_DATA_STRUCTS)
1703   if (AbstractDisassembler::show_structs()) {
1704     methodHandle mh(Thread::current(), _method);
1705     if (printmethod || PrintDebugInfo || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDebugInfo)) {
1706       print_scopes();
1707       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1708     }
1709     if (printmethod || PrintRelocations || CompilerOracle::has_option(mh, CompileCommandEnum::PrintRelocations)) {
1710       print_relocations();
1711       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1712     }
1713     if (printmethod || PrintDependencies || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDependencies)) {
1714       print_dependencies_on(tty);
1715       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1716     }
1717     if (printmethod || PrintExceptionHandlers) {
1718       print_handler_table();
1719       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1720       print_nul_chk_table();
1721       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1722     }
1723 
1724     if (printmethod) {
1725       print_recorded_oops();
1726       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1727       print_recorded_metadata();
1728       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1729     }
1730   }
1731 #endif
1732 
1733   if (xtty != nullptr) {
1734     xtty->tail("print_nmethod");
1735   }
1736 }
1737 
1738 
1739 // Promote one word from an assembly-time handle to a live embedded oop.
1740 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1741   if (handle == nullptr ||
1742       // As a special case, IC oops are initialized to 1 or -1.
1743       handle == (jobject) Universe::non_oop_word()) {
1744     *(void**)dest = handle;
1745   } else {
1746     *dest = JNIHandles::resolve_non_null(handle);
1747   }
1748 }
1749 
1750 
1751 // Have to have the same name because it's called by a template
1752 void nmethod::copy_values(GrowableArray<jobject>* array) {
1753   int length = array->length();
1754   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1755   oop* dest = oops_begin();
1756   for (int index = 0 ; index < length; index++) {
1757     initialize_immediate_oop(&dest[index], array->at(index));
1758   }
1759 
1760   // Now we can fix up all the oops in the code.  We need to do this
1761   // in the code because the assembler uses jobjects as placeholders.
1762   // The code and relocations have already been initialized by the
1763   // CodeBlob constructor, so it is valid even at this early point to
1764   // iterate over relocations and patch the code.
1765   fix_oop_relocations(nullptr, nullptr, /*initialize_immediates=*/ true);
1766 }
1767 
1768 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1769   int length = array->length();
1770   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1771   Metadata** dest = metadata_begin();
1772   for (int index = 0 ; index < length; index++) {
1773     dest[index] = array->at(index);
1774   }
1775 }
1776 
1777 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1778   // re-patch all oop-bearing instructions, just in case some oops moved
1779   RelocIterator iter(this, begin, end);
1780   while (iter.next()) {
1781     if (iter.type() == relocInfo::oop_type) {
1782       oop_Relocation* reloc = iter.oop_reloc();
1783       if (initialize_immediates && reloc->oop_is_immediate()) {
1784         oop* dest = reloc->oop_addr();
1785         jobject obj = *reinterpret_cast<jobject*>(dest);
1786         initialize_immediate_oop(dest, obj);
1787       }
1788       // Refresh the oop-related bits of this instruction.
1789       reloc->fix_oop_relocation();
1790     } else if (iter.type() == relocInfo::metadata_type) {
1791       metadata_Relocation* reloc = iter.metadata_reloc();
1792       reloc->fix_metadata_relocation();
1793     }
1794   }
1795 }
1796 
1797 static void install_post_call_nop_displacement(nmethod* nm, address pc) {
1798   NativePostCallNop* nop = nativePostCallNop_at((address) pc);
1799   intptr_t cbaddr = (intptr_t) nm;
1800   intptr_t offset = ((intptr_t) pc) - cbaddr;
1801 
1802   int oopmap_slot = nm->oop_maps()->find_slot_for_offset(int((intptr_t) pc - (intptr_t) nm->code_begin()));
1803   if (oopmap_slot < 0) { // this can happen at asynchronous (non-safepoint) stackwalks
1804     log_debug(codecache)("failed to find oopmap for cb: " INTPTR_FORMAT " offset: %d", cbaddr, (int) offset);
1805   } else if (!nop->patch(oopmap_slot, offset)) {
1806     log_debug(codecache)("failed to encode %d %d", oopmap_slot, (int) offset);
1807   }
1808 }
1809 
1810 void nmethod::finalize_relocations() {
1811   NoSafepointVerifier nsv;
1812 
1813   GrowableArray<NativeMovConstReg*> virtual_call_data;
1814 
1815   // Make sure that post call nops fill in nmethod offsets eagerly so
1816   // we don't have to race with deoptimization
1817   RelocIterator iter(this);
1818   while (iter.next()) {
1819     if (iter.type() == relocInfo::virtual_call_type) {
1820       virtual_call_Relocation* r = iter.virtual_call_reloc();
1821       NativeMovConstReg* value = nativeMovConstReg_at(r->cached_value());
1822       virtual_call_data.append(value);
1823     } else if (iter.type() == relocInfo::post_call_nop_type) {
1824       post_call_nop_Relocation* const reloc = iter.post_call_nop_reloc();
1825       address pc = reloc->addr();
1826       install_post_call_nop_displacement(this, pc);
1827     }
1828   }
1829 
1830   if (virtual_call_data.length() > 0) {
1831     // We allocate a block of CompiledICData per nmethod so the GC can purge this faster.
1832     _compiled_ic_data = new CompiledICData[virtual_call_data.length()];
1833     CompiledICData* next_data = _compiled_ic_data;
1834 
1835     for (NativeMovConstReg* value : virtual_call_data) {
1836       value->set_data((intptr_t)next_data);
1837       next_data++;
1838     }
1839   }
1840 }
1841 
1842 void nmethod::make_deoptimized() {
1843   if (!Continuations::enabled()) {
1844     // Don't deopt this again.
1845     set_deoptimized_done();
1846     return;
1847   }
1848 
1849   assert(method() == nullptr || can_be_deoptimized(), "");
1850 
1851   CompiledICLocker ml(this);
1852   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1853 
1854   // If post call nops have been already patched, we can just bail-out.
1855   if (has_been_deoptimized()) {
1856     return;
1857   }
1858 
1859   ResourceMark rm;
1860   RelocIterator iter(this, oops_reloc_begin());
1861 
1862   while (iter.next()) {
1863 
1864     switch (iter.type()) {
1865       case relocInfo::virtual_call_type: {
1866         CompiledIC *ic = CompiledIC_at(&iter);
1867         address pc = ic->end_of_call();
1868         NativePostCallNop* nop = nativePostCallNop_at(pc);
1869         if (nop != nullptr) {
1870           nop->make_deopt();
1871         }
1872         assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
1873         break;
1874       }
1875       case relocInfo::static_call_type:
1876       case relocInfo::opt_virtual_call_type: {
1877         CompiledDirectCall *csc = CompiledDirectCall::at(iter.reloc());
1878         address pc = csc->end_of_call();
1879         NativePostCallNop* nop = nativePostCallNop_at(pc);
1880         //tty->print_cr(" - static pc %p", pc);
1881         if (nop != nullptr) {
1882           nop->make_deopt();
1883         }
1884         // We can't assert here, there are some calls to stubs / runtime
1885         // that have reloc data and doesn't have a post call NOP.
1886         //assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
1887         break;
1888       }
1889       default:
1890         break;
1891     }
1892   }
1893   // Don't deopt this again.
1894   set_deoptimized_done();
1895 }
1896 
1897 void nmethod::verify_clean_inline_caches() {
1898   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1899 
1900   ResourceMark rm;
1901   RelocIterator iter(this, oops_reloc_begin());
1902   while(iter.next()) {
1903     switch(iter.type()) {
1904       case relocInfo::virtual_call_type: {
1905         CompiledIC *ic = CompiledIC_at(&iter);
1906         CodeBlob *cb = CodeCache::find_blob(ic->destination());
1907         assert(cb != nullptr, "destination not in CodeBlob?");
1908         nmethod* nm = cb->as_nmethod_or_null();
1909         if (nm != nullptr) {
1910           // Verify that inline caches pointing to bad nmethods are clean
1911           if (!nm->is_in_use() || nm->is_unloading()) {
1912             assert(ic->is_clean(), "IC should be clean");
1913           }
1914         }
1915         break;
1916       }
1917       case relocInfo::static_call_type:
1918       case relocInfo::opt_virtual_call_type: {
1919         CompiledDirectCall *cdc = CompiledDirectCall::at(iter.reloc());
1920         CodeBlob *cb = CodeCache::find_blob(cdc->destination());
1921         assert(cb != nullptr, "destination not in CodeBlob?");
1922         nmethod* nm = cb->as_nmethod_or_null();
1923         if (nm != nullptr) {
1924           // Verify that inline caches pointing to bad nmethods are clean
1925           if (!nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
1926             assert(cdc->is_clean(), "IC should be clean");
1927           }
1928         }
1929         break;
1930       }
1931       default:
1932         break;
1933     }
1934   }
1935 }
1936 
1937 void nmethod::mark_as_maybe_on_stack() {
1938   Atomic::store(&_gc_epoch, CodeCache::gc_epoch());
1939 }
1940 
1941 bool nmethod::is_maybe_on_stack() {
1942   // If the condition below is true, it means that the nmethod was found to
1943   // be alive the previous completed marking cycle.
1944   return Atomic::load(&_gc_epoch) >= CodeCache::previous_completed_gc_marking_cycle();
1945 }
1946 
1947 void nmethod::inc_decompile_count() {
1948   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1949   // Could be gated by ProfileTraps, but do not bother...
1950   Method* m = method();
1951   if (m == nullptr)  return;
1952   MethodData* mdo = m->method_data();
1953   if (mdo == nullptr)  return;
1954   // There is a benign race here.  See comments in methodData.hpp.
1955   mdo->inc_decompile_count();
1956 }
1957 
1958 bool nmethod::try_transition(signed char new_state_int) {
1959   signed char new_state = new_state_int;
1960   assert_lock_strong(NMethodState_lock);
1961   signed char old_state = _state;
1962   if (old_state >= new_state) {
1963     // Ensure monotonicity of transitions.
1964     return false;
1965   }
1966   Atomic::store(&_state, new_state);
1967   return true;
1968 }
1969 
1970 void nmethod::invalidate_osr_method() {
1971   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1972   // Remove from list of active nmethods
1973   if (method() != nullptr) {
1974     method()->method_holder()->remove_osr_nmethod(this);
1975   }
1976 }
1977 
1978 void nmethod::log_state_change() const {
1979   if (LogCompilation) {
1980     if (xtty != nullptr) {
1981       ttyLocker ttyl;  // keep the following output all in one block
1982       xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'",
1983                        os::current_thread_id());
1984       log_identity(xtty);
1985       xtty->stamp();
1986       xtty->end_elem();
1987     }
1988   }
1989 
1990   CompileTask::print_ul(this, "made not entrant");
1991   if (PrintCompilation) {
1992     print_on(tty, "made not entrant");
1993   }
1994 }
1995 
1996 void nmethod::unlink_from_method() {
1997   if (method() != nullptr) {
1998     method()->unlink_code(this);
1999   }
2000 }
2001 
2002 // Invalidate code
2003 bool nmethod::make_not_entrant() {
2004   // This can be called while the system is already at a safepoint which is ok
2005   NoSafepointVerifier nsv;
2006 
2007   if (is_unloading()) {
2008     // If the nmethod is unloading, then it is already not entrant through
2009     // the nmethod entry barriers. No need to do anything; GC will unload it.
2010     return false;
2011   }
2012 
2013   if (Atomic::load(&_state) == not_entrant) {
2014     // Avoid taking the lock if already in required state.
2015     // This is safe from races because the state is an end-state,
2016     // which the nmethod cannot back out of once entered.
2017     // No need for fencing either.
2018     return false;
2019   }
2020 
2021   {
2022     // Enter critical section.  Does not block for safepoint.
2023     ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
2024 
2025     if (Atomic::load(&_state) == not_entrant) {
2026       // another thread already performed this transition so nothing
2027       // to do, but return false to indicate this.
2028       return false;
2029     }
2030 
2031     if (is_osr_method()) {
2032       // This logic is equivalent to the logic below for patching the
2033       // verified entry point of regular methods.
2034       // this effectively makes the osr nmethod not entrant
2035       invalidate_osr_method();
2036     } else {
2037       // The caller can be calling the method statically or through an inline
2038       // cache call.
2039       NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
2040                                        SharedRuntime::get_handle_wrong_method_stub());
2041     }
2042 
2043     if (update_recompile_counts()) {
2044       // Mark the method as decompiled.
2045       inc_decompile_count();
2046     }
2047 
2048     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2049     if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2050       // If nmethod entry barriers are not supported, we won't mark
2051       // nmethods as on-stack when they become on-stack. So we
2052       // degrade to a less accurate flushing strategy, for now.
2053       mark_as_maybe_on_stack();
2054     }
2055 
2056     // Change state
2057     bool success = try_transition(not_entrant);
2058     assert(success, "Transition can't fail");
2059 
2060     // Log the transition once
2061     log_state_change();
2062 
2063     // Remove nmethod from method.
2064     unlink_from_method();
2065 
2066   } // leave critical region under NMethodState_lock
2067 
2068 #if INCLUDE_JVMCI
2069   // Invalidate can't occur while holding the Patching lock
2070   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2071   if (nmethod_data != nullptr) {
2072     nmethod_data->invalidate_nmethod_mirror(this);
2073   }
2074 #endif
2075 
2076 #ifdef ASSERT
2077   if (is_osr_method() && method() != nullptr) {
2078     // Make sure osr nmethod is invalidated, i.e. not on the list
2079     bool found = method()->method_holder()->remove_osr_nmethod(this);
2080     assert(!found, "osr nmethod should have been invalidated");
2081   }
2082 #endif
2083 
2084   return true;
2085 }
2086 
2087 // For concurrent GCs, there must be a handshake between unlink and flush
2088 void nmethod::unlink() {
2089   if (is_unlinked()) {
2090     // Already unlinked.
2091     return;
2092   }
2093 
2094   flush_dependencies();
2095 
2096   // unlink_from_method will take the NMethodState_lock.
2097   // In this case we don't strictly need it when unlinking nmethods from
2098   // the Method, because it is only concurrently unlinked by
2099   // the entry barrier, which acquires the per nmethod lock.
2100   unlink_from_method();
2101 
2102   if (is_osr_method()) {
2103     invalidate_osr_method();
2104   }
2105 
2106 #if INCLUDE_JVMCI
2107   // Clear the link between this nmethod and a HotSpotNmethod mirror
2108   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2109   if (nmethod_data != nullptr) {
2110     nmethod_data->invalidate_nmethod_mirror(this);
2111   }
2112 #endif
2113 
2114   // Post before flushing as jmethodID is being used
2115   post_compiled_method_unload();
2116 
2117   // Register for flushing when it is safe. For concurrent class unloading,
2118   // that would be after the unloading handshake, and for STW class unloading
2119   // that would be when getting back to the VM thread.
2120   ClassUnloadingContext::context()->register_unlinked_nmethod(this);
2121 }
2122 
2123 void nmethod::purge(bool unregister_nmethod) {
2124 
2125   MutexLocker ml(CodeCache_lock, Mutex::_no_safepoint_check_flag);
2126 
2127   // completely deallocate this method
2128   Events::log_nmethod_flush(Thread::current(), "flushing %s nmethod " INTPTR_FORMAT, is_osr_method() ? "osr" : "", p2i(this));
2129   log_debug(codecache)("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
2130                        "/Free CodeCache:" SIZE_FORMAT "Kb",
2131                        is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
2132                        CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
2133 
2134   // We need to deallocate any ExceptionCache data.
2135   // Note that we do not need to grab the nmethod lock for this, it
2136   // better be thread safe if we're disposing of it!
2137   ExceptionCache* ec = exception_cache();
2138   while(ec != nullptr) {
2139     ExceptionCache* next = ec->next();
2140     delete ec;
2141     ec = next;
2142   }
2143   if (_pc_desc_container != nullptr) {
2144     delete _pc_desc_container;
2145   }
2146   delete[] _compiled_ic_data;
2147 
2148   if (_immutable_data != data_end()) {
2149     os::free(_immutable_data);
2150     _immutable_data = data_end(); // Valid not null address
2151   }
2152   if (unregister_nmethod) {
2153     Universe::heap()->unregister_nmethod(this);
2154   }
2155   CodeCache::unregister_old_nmethod(this);
2156 
2157   CodeBlob::purge();
2158 }
2159 
2160 oop nmethod::oop_at(int index) const {
2161   if (index == 0) {
2162     return nullptr;
2163   }
2164   return NMethodAccess<AS_NO_KEEPALIVE>::oop_load(oop_addr_at(index));
2165 }
2166 
2167 oop nmethod::oop_at_phantom(int index) const {
2168   if (index == 0) {
2169     return nullptr;
2170   }
2171   return NMethodAccess<ON_PHANTOM_OOP_REF>::oop_load(oop_addr_at(index));
2172 }
2173 
2174 //
2175 // Notify all classes this nmethod is dependent on that it is no
2176 // longer dependent.
2177 
2178 void nmethod::flush_dependencies() {
2179   if (!has_flushed_dependencies()) {
2180     set_has_flushed_dependencies(true);
2181     for (Dependencies::DepStream deps(this); deps.next(); ) {
2182       if (deps.type() == Dependencies::call_site_target_value) {
2183         // CallSite dependencies are managed on per-CallSite instance basis.
2184         oop call_site = deps.argument_oop(0);
2185         MethodHandles::clean_dependency_context(call_site);
2186       } else {
2187         InstanceKlass* ik = deps.context_type();
2188         if (ik == nullptr) {
2189           continue;  // ignore things like evol_method
2190         }
2191         // During GC liveness of dependee determines class that needs to be updated.
2192         // The GC may clean dependency contexts concurrently and in parallel.
2193         ik->clean_dependency_context();
2194       }
2195     }
2196   }
2197 }
2198 
2199 void nmethod::post_compiled_method(CompileTask* task) {
2200   task->mark_success();
2201   task->set_nm_content_size(content_size());
2202   task->set_nm_insts_size(insts_size());
2203   task->set_nm_total_size(total_size());
2204 
2205   // JVMTI -- compiled method notification (must be done outside lock)
2206   post_compiled_method_load_event();
2207 
2208   if (CompilationLog::log() != nullptr) {
2209     CompilationLog::log()->log_nmethod(JavaThread::current(), this);
2210   }
2211 
2212   const DirectiveSet* directive = task->directive();
2213   maybe_print_nmethod(directive);
2214 }
2215 
2216 // ------------------------------------------------------------------
2217 // post_compiled_method_load_event
2218 // new method for install_code() path
2219 // Transfer information from compilation to jvmti
2220 void nmethod::post_compiled_method_load_event(JvmtiThreadState* state) {
2221   // This is a bad time for a safepoint.  We don't want
2222   // this nmethod to get unloaded while we're queueing the event.
2223   NoSafepointVerifier nsv;
2224 
2225   Method* m = method();
2226   HOTSPOT_COMPILED_METHOD_LOAD(
2227       (char *) m->klass_name()->bytes(),
2228       m->klass_name()->utf8_length(),
2229       (char *) m->name()->bytes(),
2230       m->name()->utf8_length(),
2231       (char *) m->signature()->bytes(),
2232       m->signature()->utf8_length(),
2233       insts_begin(), insts_size());
2234 
2235 
2236   if (JvmtiExport::should_post_compiled_method_load()) {
2237     // Only post unload events if load events are found.
2238     set_load_reported();
2239     // If a JavaThread hasn't been passed in, let the Service thread
2240     // (which is a real Java thread) post the event
2241     JvmtiDeferredEvent event = JvmtiDeferredEvent::compiled_method_load_event(this);
2242     if (state == nullptr) {
2243       // Execute any barrier code for this nmethod as if it's called, since
2244       // keeping it alive looks like stack walking.
2245       run_nmethod_entry_barrier();
2246       ServiceThread::enqueue_deferred_event(&event);
2247     } else {
2248       // This enters the nmethod barrier outside in the caller.
2249       state->enqueue_event(&event);
2250     }
2251   }
2252 }
2253 
2254 void nmethod::post_compiled_method_unload() {
2255   assert(_method != nullptr, "just checking");
2256   DTRACE_METHOD_UNLOAD_PROBE(method());
2257 
2258   // If a JVMTI agent has enabled the CompiledMethodUnload event then
2259   // post the event. The Method* will not be valid when this is freed.
2260 
2261   // Don't bother posting the unload if the load event wasn't posted.
2262   if (load_reported() && JvmtiExport::should_post_compiled_method_unload()) {
2263     JvmtiDeferredEvent event =
2264       JvmtiDeferredEvent::compiled_method_unload_event(
2265           method()->jmethod_id(), insts_begin());
2266     ServiceThread::enqueue_deferred_event(&event);
2267   }
2268 }
2269 
2270 // Iterate over metadata calling this function.   Used by RedefineClasses
2271 void nmethod::metadata_do(MetadataClosure* f) {
2272   {
2273     // Visit all immediate references that are embedded in the instruction stream.
2274     RelocIterator iter(this, oops_reloc_begin());
2275     while (iter.next()) {
2276       if (iter.type() == relocInfo::metadata_type) {
2277         metadata_Relocation* r = iter.metadata_reloc();
2278         // In this metadata, we must only follow those metadatas directly embedded in
2279         // the code.  Other metadatas (oop_index>0) are seen as part of
2280         // the metadata section below.
2281         assert(1 == (r->metadata_is_immediate()) +
2282                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2283                "metadata must be found in exactly one place");
2284         if (r->metadata_is_immediate() && r->metadata_value() != nullptr) {
2285           Metadata* md = r->metadata_value();
2286           if (md != _method) f->do_metadata(md);
2287         }
2288       } else if (iter.type() == relocInfo::virtual_call_type) {
2289         // Check compiledIC holders associated with this nmethod
2290         ResourceMark rm;
2291         CompiledIC *ic = CompiledIC_at(&iter);
2292         ic->metadata_do(f);
2293       }
2294     }
2295   }
2296 
2297   // Visit the metadata section
2298   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2299     if (*p == Universe::non_oop_word() || *p == nullptr)  continue;  // skip non-oops
2300     Metadata* md = *p;
2301     f->do_metadata(md);
2302   }
2303 
2304   // Visit metadata not embedded in the other places.
2305   if (_method != nullptr) f->do_metadata(_method);
2306 }
2307 
2308 // Heuristic for nuking nmethods even though their oops are live.
2309 // Main purpose is to reduce code cache pressure and get rid of
2310 // nmethods that don't seem to be all that relevant any longer.
2311 bool nmethod::is_cold() {
2312   if (!MethodFlushing || is_native_method() || is_not_installed()) {
2313     // No heuristic unloading at all
2314     return false;
2315   }
2316 
2317   if (!is_maybe_on_stack() && is_not_entrant()) {
2318     // Not entrant nmethods that are not on any stack can just
2319     // be removed
2320     return true;
2321   }
2322 
2323   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2324   if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2325     // On platforms that don't support nmethod entry barriers, we can't
2326     // trust the temporal aspect of the gc epochs. So we can't detect
2327     // cold nmethods on such platforms.
2328     return false;
2329   }
2330 
2331   if (!UseCodeCacheFlushing) {
2332     // Bail out if we don't heuristically remove nmethods
2333     return false;
2334   }
2335 
2336   // Other code can be phased out more gradually after N GCs
2337   return CodeCache::previous_completed_gc_marking_cycle() > _gc_epoch + 2 * CodeCache::cold_gc_count();
2338 }
2339 
2340 // The _is_unloading_state encodes a tuple comprising the unloading cycle
2341 // and the result of IsUnloadingBehaviour::is_unloading() for that cycle.
2342 // This is the bit layout of the _is_unloading_state byte: 00000CCU
2343 // CC refers to the cycle, which has 2 bits, and U refers to the result of
2344 // IsUnloadingBehaviour::is_unloading() for that unloading cycle.
2345 
2346 class IsUnloadingState: public AllStatic {
2347   static const uint8_t _is_unloading_mask = 1;
2348   static const uint8_t _is_unloading_shift = 0;
2349   static const uint8_t _unloading_cycle_mask = 6;
2350   static const uint8_t _unloading_cycle_shift = 1;
2351 
2352   static uint8_t set_is_unloading(uint8_t state, bool value) {
2353     state &= (uint8_t)~_is_unloading_mask;
2354     if (value) {
2355       state |= 1 << _is_unloading_shift;
2356     }
2357     assert(is_unloading(state) == value, "unexpected unloading cycle overflow");
2358     return state;
2359   }
2360 
2361   static uint8_t set_unloading_cycle(uint8_t state, uint8_t value) {
2362     state &= (uint8_t)~_unloading_cycle_mask;
2363     state |= (uint8_t)(value << _unloading_cycle_shift);
2364     assert(unloading_cycle(state) == value, "unexpected unloading cycle overflow");
2365     return state;
2366   }
2367 
2368 public:
2369   static bool is_unloading(uint8_t state) { return (state & _is_unloading_mask) >> _is_unloading_shift == 1; }
2370   static uint8_t unloading_cycle(uint8_t state) { return (state & _unloading_cycle_mask) >> _unloading_cycle_shift; }
2371 
2372   static uint8_t create(bool is_unloading, uint8_t unloading_cycle) {
2373     uint8_t state = 0;
2374     state = set_is_unloading(state, is_unloading);
2375     state = set_unloading_cycle(state, unloading_cycle);
2376     return state;
2377   }
2378 };
2379 
2380 bool nmethod::is_unloading() {
2381   uint8_t state = Atomic::load(&_is_unloading_state);
2382   bool state_is_unloading = IsUnloadingState::is_unloading(state);
2383   if (state_is_unloading) {
2384     return true;
2385   }
2386   uint8_t state_unloading_cycle = IsUnloadingState::unloading_cycle(state);
2387   uint8_t current_cycle = CodeCache::unloading_cycle();
2388   if (state_unloading_cycle == current_cycle) {
2389     return false;
2390   }
2391 
2392   // The IsUnloadingBehaviour is responsible for calculating if the nmethod
2393   // should be unloaded. This can be either because there is a dead oop,
2394   // or because is_cold() heuristically determines it is time to unload.
2395   state_unloading_cycle = current_cycle;
2396   state_is_unloading = IsUnloadingBehaviour::is_unloading(this);
2397   uint8_t new_state = IsUnloadingState::create(state_is_unloading, state_unloading_cycle);
2398 
2399   // Note that if an nmethod has dead oops, everyone will agree that the
2400   // nmethod is_unloading. However, the is_cold heuristics can yield
2401   // different outcomes, so we guard the computed result with a CAS
2402   // to ensure all threads have a shared view of whether an nmethod
2403   // is_unloading or not.
2404   uint8_t found_state = Atomic::cmpxchg(&_is_unloading_state, state, new_state, memory_order_relaxed);
2405 
2406   if (found_state == state) {
2407     // First to change state, we win
2408     return state_is_unloading;
2409   } else {
2410     // State already set, so use it
2411     return IsUnloadingState::is_unloading(found_state);
2412   }
2413 }
2414 
2415 void nmethod::clear_unloading_state() {
2416   uint8_t state = IsUnloadingState::create(false, CodeCache::unloading_cycle());
2417   Atomic::store(&_is_unloading_state, state);
2418 }
2419 
2420 
2421 // This is called at the end of the strong tracing/marking phase of a
2422 // GC to unload an nmethod if it contains otherwise unreachable
2423 // oops or is heuristically found to be not important.
2424 void nmethod::do_unloading(bool unloading_occurred) {
2425   // Make sure the oop's ready to receive visitors
2426   if (is_unloading()) {
2427     unlink();
2428   } else {
2429     unload_nmethod_caches(unloading_occurred);
2430     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2431     if (bs_nm != nullptr) {
2432       bs_nm->disarm(this);
2433     }
2434   }
2435 }
2436 
2437 void nmethod::oops_do(OopClosure* f, bool allow_dead) {
2438   // Prevent extra code cache walk for platforms that don't have immediate oops.
2439   if (relocInfo::mustIterateImmediateOopsInCode()) {
2440     RelocIterator iter(this, oops_reloc_begin());
2441 
2442     while (iter.next()) {
2443       if (iter.type() == relocInfo::oop_type ) {
2444         oop_Relocation* r = iter.oop_reloc();
2445         // In this loop, we must only follow those oops directly embedded in
2446         // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
2447         assert(1 == (r->oop_is_immediate()) +
2448                (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2449                "oop must be found in exactly one place");
2450         if (r->oop_is_immediate() && r->oop_value() != nullptr) {
2451           f->do_oop(r->oop_addr());
2452         }
2453       }
2454     }
2455   }
2456 
2457   // Scopes
2458   // This includes oop constants not inlined in the code stream.
2459   for (oop* p = oops_begin(); p < oops_end(); p++) {
2460     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
2461     f->do_oop(p);
2462   }
2463 }
2464 
2465 void nmethod::follow_nmethod(OopIterateClosure* cl) {
2466   // Process oops in the nmethod
2467   oops_do(cl);
2468 
2469   // CodeCache unloading support
2470   mark_as_maybe_on_stack();
2471 
2472   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2473   bs_nm->disarm(this);
2474 
2475   // There's an assumption made that this function is not used by GCs that
2476   // relocate objects, and therefore we don't call fix_oop_relocations.
2477 }
2478 
2479 nmethod* volatile nmethod::_oops_do_mark_nmethods;
2480 
2481 void nmethod::oops_do_log_change(const char* state) {
2482   LogTarget(Trace, gc, nmethod) lt;
2483   if (lt.is_enabled()) {
2484     LogStream ls(lt);
2485     CompileTask::print(&ls, this, state, true /* short_form */);
2486   }
2487 }
2488 
2489 bool nmethod::oops_do_try_claim() {
2490   if (oops_do_try_claim_weak_request()) {
2491     nmethod* result = oops_do_try_add_to_list_as_weak_done();
2492     assert(result == nullptr, "adding to global list as weak done must always succeed.");
2493     return true;
2494   }
2495   return false;
2496 }
2497 
2498 bool nmethod::oops_do_try_claim_weak_request() {
2499   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2500 
2501   if ((_oops_do_mark_link == nullptr) &&
2502       (Atomic::replace_if_null(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag)))) {
2503     oops_do_log_change("oops_do, mark weak request");
2504     return true;
2505   }
2506   return false;
2507 }
2508 
2509 void nmethod::oops_do_set_strong_done(nmethod* old_head) {
2510   _oops_do_mark_link = mark_link(old_head, claim_strong_done_tag);
2511 }
2512 
2513 nmethod::oops_do_mark_link* nmethod::oops_do_try_claim_strong_done() {
2514   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2515 
2516   oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, mark_link(nullptr, claim_weak_request_tag), mark_link(this, claim_strong_done_tag));
2517   if (old_next == nullptr) {
2518     oops_do_log_change("oops_do, mark strong done");
2519   }
2520   return old_next;
2521 }
2522 
2523 nmethod::oops_do_mark_link* nmethod::oops_do_try_add_strong_request(nmethod::oops_do_mark_link* next) {
2524   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2525   assert(next == mark_link(this, claim_weak_request_tag), "Should be claimed as weak");
2526 
2527   oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(this, claim_strong_request_tag));
2528   if (old_next == next) {
2529     oops_do_log_change("oops_do, mark strong request");
2530   }
2531   return old_next;
2532 }
2533 
2534 bool nmethod::oops_do_try_claim_weak_done_as_strong_done(nmethod::oops_do_mark_link* next) {
2535   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2536   assert(extract_state(next) == claim_weak_done_tag, "Should be claimed as weak done");
2537 
2538   oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(extract_nmethod(next), claim_strong_done_tag));
2539   if (old_next == next) {
2540     oops_do_log_change("oops_do, mark weak done -> mark strong done");
2541     return true;
2542   }
2543   return false;
2544 }
2545 
2546 nmethod* nmethod::oops_do_try_add_to_list_as_weak_done() {
2547   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2548 
2549   assert(extract_state(_oops_do_mark_link) == claim_weak_request_tag ||
2550          extract_state(_oops_do_mark_link) == claim_strong_request_tag,
2551          "must be but is nmethod " PTR_FORMAT " %u", p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
2552 
2553   nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this);
2554   // Self-loop if needed.
2555   if (old_head == nullptr) {
2556     old_head = this;
2557   }
2558   // Try to install end of list and weak done tag.
2559   if (Atomic::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)) {
2560     oops_do_log_change("oops_do, mark weak done");
2561     return nullptr;
2562   } else {
2563     return old_head;
2564   }
2565 }
2566 
2567 void nmethod::oops_do_add_to_list_as_strong_done() {
2568   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2569 
2570   nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this);
2571   // Self-loop if needed.
2572   if (old_head == nullptr) {
2573     old_head = this;
2574   }
2575   assert(_oops_do_mark_link == mark_link(this, claim_strong_done_tag), "must be but is nmethod " PTR_FORMAT " state %u",
2576          p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
2577 
2578   oops_do_set_strong_done(old_head);
2579 }
2580 
2581 void nmethod::oops_do_process_weak(OopsDoProcessor* p) {
2582   if (!oops_do_try_claim_weak_request()) {
2583     // Failed to claim for weak processing.
2584     oops_do_log_change("oops_do, mark weak request fail");
2585     return;
2586   }
2587 
2588   p->do_regular_processing(this);
2589 
2590   nmethod* old_head = oops_do_try_add_to_list_as_weak_done();
2591   if (old_head == nullptr) {
2592     return;
2593   }
2594   oops_do_log_change("oops_do, mark weak done fail");
2595   // Adding to global list failed, another thread added a strong request.
2596   assert(extract_state(_oops_do_mark_link) == claim_strong_request_tag,
2597          "must be but is %u", extract_state(_oops_do_mark_link));
2598 
2599   oops_do_log_change("oops_do, mark weak request -> mark strong done");
2600 
2601   oops_do_set_strong_done(old_head);
2602   // Do missing strong processing.
2603   p->do_remaining_strong_processing(this);
2604 }
2605 
2606 void nmethod::oops_do_process_strong(OopsDoProcessor* p) {
2607   oops_do_mark_link* next_raw = oops_do_try_claim_strong_done();
2608   if (next_raw == nullptr) {
2609     p->do_regular_processing(this);
2610     oops_do_add_to_list_as_strong_done();
2611     return;
2612   }
2613   // Claim failed. Figure out why and handle it.
2614   if (oops_do_has_weak_request(next_raw)) {
2615     oops_do_mark_link* old = next_raw;
2616     // Claim failed because being weak processed (state == "weak request").
2617     // Try to request deferred strong processing.
2618     next_raw = oops_do_try_add_strong_request(old);
2619     if (next_raw == old) {
2620       // Successfully requested deferred strong processing.
2621       return;
2622     }
2623     // Failed because of a concurrent transition. No longer in "weak request" state.
2624   }
2625   if (oops_do_has_any_strong_state(next_raw)) {
2626     // Already claimed for strong processing or requested for such.
2627     return;
2628   }
2629   if (oops_do_try_claim_weak_done_as_strong_done(next_raw)) {
2630     // Successfully claimed "weak done" as "strong done". Do the missing marking.
2631     p->do_remaining_strong_processing(this);
2632     return;
2633   }
2634   // Claim failed, some other thread got it.
2635 }
2636 
2637 void nmethod::oops_do_marking_prologue() {
2638   assert_at_safepoint();
2639 
2640   log_trace(gc, nmethod)("oops_do_marking_prologue");
2641   assert(_oops_do_mark_nmethods == nullptr, "must be empty");
2642 }
2643 
2644 void nmethod::oops_do_marking_epilogue() {
2645   assert_at_safepoint();
2646 
2647   nmethod* next = _oops_do_mark_nmethods;
2648   _oops_do_mark_nmethods = nullptr;
2649   if (next != nullptr) {
2650     nmethod* cur;
2651     do {
2652       cur = next;
2653       next = extract_nmethod(cur->_oops_do_mark_link);
2654       cur->_oops_do_mark_link = nullptr;
2655       DEBUG_ONLY(cur->verify_oop_relocations());
2656 
2657       LogTarget(Trace, gc, nmethod) lt;
2658       if (lt.is_enabled()) {
2659         LogStream ls(lt);
2660         CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
2661       }
2662       // End if self-loop has been detected.
2663     } while (cur != next);
2664   }
2665   log_trace(gc, nmethod)("oops_do_marking_epilogue");
2666 }
2667 
2668 inline bool includes(void* p, void* from, void* to) {
2669   return from <= p && p < to;
2670 }
2671 
2672 
2673 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2674   assert(count >= 2, "must be sentinel values, at least");
2675 
2676 #ifdef ASSERT
2677   // must be sorted and unique; we do a binary search in find_pc_desc()
2678   int prev_offset = pcs[0].pc_offset();
2679   assert(prev_offset == PcDesc::lower_offset_limit,
2680          "must start with a sentinel");
2681   for (int i = 1; i < count; i++) {
2682     int this_offset = pcs[i].pc_offset();
2683     assert(this_offset > prev_offset, "offsets must be sorted");
2684     prev_offset = this_offset;
2685   }
2686   assert(prev_offset == PcDesc::upper_offset_limit,
2687          "must end with a sentinel");
2688 #endif //ASSERT
2689 
2690   // Search for MethodHandle invokes and tag the nmethod.
2691   for (int i = 0; i < count; i++) {
2692     if (pcs[i].is_method_handle_invoke()) {
2693       set_has_method_handle_invokes(true);
2694       break;
2695     }
2696   }
2697   assert(has_method_handle_invokes() == (_deopt_mh_handler_offset != -1), "must have deopt mh handler");
2698 
2699   int size = count * sizeof(PcDesc);
2700   assert(scopes_pcs_size() >= size, "oob");
2701   memcpy(scopes_pcs_begin(), pcs, size);
2702 
2703   // Adjust the final sentinel downward.
2704   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2705   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2706   last_pc->set_pc_offset(content_size() + 1);
2707   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2708     // Fill any rounding gaps with copies of the last record.
2709     last_pc[1] = last_pc[0];
2710   }
2711   // The following assert could fail if sizeof(PcDesc) is not
2712   // an integral multiple of oopSize (the rounding term).
2713   // If it fails, change the logic to always allocate a multiple
2714   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2715   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2716 }
2717 
2718 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2719   assert(scopes_data_size() >= size, "oob");
2720   memcpy(scopes_data_begin(), buffer, size);
2721 }
2722 
2723 #ifdef ASSERT
2724 static PcDesc* linear_search(int pc_offset, bool approximate, PcDesc* lower, PcDesc* upper) {
2725   PcDesc* res = nullptr;
2726   assert(lower != nullptr && lower->pc_offset() == PcDesc::lower_offset_limit,
2727          "must start with a sentinel");
2728   // lower + 1 to exclude initial sentinel
2729   for (PcDesc* p = lower + 1; p < upper; p++) {
2730     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
2731     if (match_desc(p, pc_offset, approximate)) {
2732       if (res == nullptr) {
2733         res = p;
2734       } else {
2735         res = (PcDesc*) badAddress;
2736       }
2737     }
2738   }
2739   return res;
2740 }
2741 #endif
2742 
2743 
2744 #ifndef PRODUCT
2745 // Version of method to collect statistic
2746 PcDesc* PcDescContainer::find_pc_desc(address pc, bool approximate, address code_begin,
2747                                       PcDesc* lower, PcDesc* upper) {
2748   ++pc_nmethod_stats.pc_desc_queries;
2749   if (approximate) ++pc_nmethod_stats.pc_desc_approx;
2750 
2751   PcDesc* desc = _pc_desc_cache.last_pc_desc();
2752   assert(desc != nullptr, "PcDesc cache should be initialized already");
2753   if (desc->pc_offset() == (pc - code_begin)) {
2754     // Cached value matched
2755     ++pc_nmethod_stats.pc_desc_tests;
2756     ++pc_nmethod_stats.pc_desc_repeats;
2757     return desc;
2758   }
2759   return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
2760 }
2761 #endif
2762 
2763 // Finds a PcDesc with real-pc equal to "pc"
2764 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, address code_begin,
2765                                                PcDesc* lower_incl, PcDesc* upper_incl) {
2766   if ((pc < code_begin) ||
2767       (pc - code_begin) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2768     return nullptr;  // PC is wildly out of range
2769   }
2770   int pc_offset = (int) (pc - code_begin);
2771 
2772   // Check the PcDesc cache if it contains the desired PcDesc
2773   // (This as an almost 100% hit rate.)
2774   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2775   if (res != nullptr) {
2776     assert(res == linear_search(pc_offset, approximate, lower_incl, upper_incl), "cache ok");
2777     return res;
2778   }
2779 
2780   // Fallback algorithm: quasi-linear search for the PcDesc
2781   // Find the last pc_offset less than the given offset.
2782   // The successor must be the required match, if there is a match at all.
2783   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2784   PcDesc* lower = lower_incl;     // this is initial sentinel
2785   PcDesc* upper = upper_incl - 1; // exclude final sentinel
2786   if (lower >= upper)  return nullptr;  // no PcDescs at all
2787 
2788 #define assert_LU_OK \
2789   /* invariant on lower..upper during the following search: */ \
2790   assert(lower->pc_offset() <  pc_offset, "sanity"); \
2791   assert(upper->pc_offset() >= pc_offset, "sanity")
2792   assert_LU_OK;
2793 
2794   // Use the last successful return as a split point.
2795   PcDesc* mid = _pc_desc_cache.last_pc_desc();
2796   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2797   if (mid->pc_offset() < pc_offset) {
2798     lower = mid;
2799   } else {
2800     upper = mid;
2801   }
2802 
2803   // Take giant steps at first (4096, then 256, then 16, then 1)
2804   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2805   const int RADIX = (1 << LOG2_RADIX);
2806   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2807     while ((mid = lower + step) < upper) {
2808       assert_LU_OK;
2809       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2810       if (mid->pc_offset() < pc_offset) {
2811         lower = mid;
2812       } else {
2813         upper = mid;
2814         break;
2815       }
2816     }
2817     assert_LU_OK;
2818   }
2819 
2820   // Sneak up on the value with a linear search of length ~16.
2821   while (true) {
2822     assert_LU_OK;
2823     mid = lower + 1;
2824     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2825     if (mid->pc_offset() < pc_offset) {
2826       lower = mid;
2827     } else {
2828       upper = mid;
2829       break;
2830     }
2831   }
2832 #undef assert_LU_OK
2833 
2834   if (match_desc(upper, pc_offset, approximate)) {
2835     assert(upper == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
2836     if (!Thread::current_in_asgct()) {
2837       // we don't want to modify the cache if we're in ASGCT
2838       // which is typically called in a signal handler
2839       _pc_desc_cache.add_pc_desc(upper);
2840     }
2841     return upper;
2842   } else {
2843     assert(nullptr == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
2844     return nullptr;
2845   }
2846 }
2847 
2848 bool nmethod::check_dependency_on(DepChange& changes) {
2849   // What has happened:
2850   // 1) a new class dependee has been added
2851   // 2) dependee and all its super classes have been marked
2852   bool found_check = false;  // set true if we are upset
2853   for (Dependencies::DepStream deps(this); deps.next(); ) {
2854     // Evaluate only relevant dependencies.
2855     if (deps.spot_check_dependency_at(changes) != nullptr) {
2856       found_check = true;
2857       NOT_DEBUG(break);
2858     }
2859   }
2860   return found_check;
2861 }
2862 
2863 // Called from mark_for_deoptimization, when dependee is invalidated.
2864 bool nmethod::is_dependent_on_method(Method* dependee) {
2865   for (Dependencies::DepStream deps(this); deps.next(); ) {
2866     if (deps.type() != Dependencies::evol_method)
2867       continue;
2868     Method* method = deps.method_argument(0);
2869     if (method == dependee) return true;
2870   }
2871   return false;
2872 }
2873 
2874 void nmethod_init() {
2875   // make sure you didn't forget to adjust the filler fields
2876   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2877 }
2878 
2879 // -----------------------------------------------------------------------------
2880 // Verification
2881 
2882 class VerifyOopsClosure: public OopClosure {
2883   nmethod* _nm;
2884   bool     _ok;
2885 public:
2886   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2887   bool ok() { return _ok; }
2888   virtual void do_oop(oop* p) {
2889     if (oopDesc::is_oop_or_null(*p)) return;
2890     // Print diagnostic information before calling print_nmethod().
2891     // Assertions therein might prevent call from returning.
2892     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2893                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2894     if (_ok) {
2895       _nm->print_nmethod(true);
2896       _ok = false;
2897     }
2898   }
2899   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2900 };
2901 
2902 class VerifyMetadataClosure: public MetadataClosure {
2903  public:
2904   void do_metadata(Metadata* md) {
2905     if (md->is_method()) {
2906       Method* method = (Method*)md;
2907       assert(!method->is_old(), "Should not be installing old methods");
2908     }
2909   }
2910 };
2911 
2912 
2913 void nmethod::verify() {
2914   if (is_not_entrant())
2915     return;
2916 
2917   // Make sure all the entry points are correctly aligned for patching.
2918   NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2919 
2920   // assert(oopDesc::is_oop(method()), "must be valid");
2921 
2922   ResourceMark rm;
2923 
2924   if (!CodeCache::contains(this)) {
2925     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2926   }
2927 
2928   if(is_native_method() )
2929     return;
2930 
2931   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2932   if (nm != this) {
2933     fatal("find_nmethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2934   }
2935 
2936   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2937     if (! p->verify(this)) {
2938       tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2939     }
2940   }
2941 
2942 #ifdef ASSERT
2943 #if INCLUDE_JVMCI
2944   {
2945     // Verify that implicit exceptions that deoptimize have a PcDesc and OopMap
2946     ImmutableOopMapSet* oms = oop_maps();
2947     ImplicitExceptionTable implicit_table(this);
2948     for (uint i = 0; i < implicit_table.len(); i++) {
2949       int exec_offset = (int) implicit_table.get_exec_offset(i);
2950       if (implicit_table.get_exec_offset(i) == implicit_table.get_cont_offset(i)) {
2951         assert(pc_desc_at(code_begin() + exec_offset) != nullptr, "missing PcDesc");
2952         bool found = false;
2953         for (int i = 0, imax = oms->count(); i < imax; i++) {
2954           if (oms->pair_at(i)->pc_offset() == exec_offset) {
2955             found = true;
2956             break;
2957           }
2958         }
2959         assert(found, "missing oopmap");
2960       }
2961     }
2962   }
2963 #endif
2964 #endif
2965 
2966   VerifyOopsClosure voc(this);
2967   oops_do(&voc);
2968   assert(voc.ok(), "embedded oops must be OK");
2969   Universe::heap()->verify_nmethod(this);
2970 
2971   assert(_oops_do_mark_link == nullptr, "_oops_do_mark_link for %s should be nullptr but is " PTR_FORMAT,
2972          nm->method()->external_name(), p2i(_oops_do_mark_link));
2973   verify_scopes();
2974 
2975   CompiledICLocker nm_verify(this);
2976   VerifyMetadataClosure vmc;
2977   metadata_do(&vmc);
2978 }
2979 
2980 
2981 void nmethod::verify_interrupt_point(address call_site, bool is_inline_cache) {
2982 
2983   // Verify IC only when nmethod installation is finished.
2984   if (!is_not_installed()) {
2985     if (CompiledICLocker::is_safe(this)) {
2986       if (is_inline_cache) {
2987         CompiledIC_at(this, call_site);
2988       } else {
2989         CompiledDirectCall::at(call_site);
2990       }
2991     } else {
2992       CompiledICLocker ml_verify(this);
2993       if (is_inline_cache) {
2994         CompiledIC_at(this, call_site);
2995       } else {
2996         CompiledDirectCall::at(call_site);
2997       }
2998     }
2999   }
3000 
3001   HandleMark hm(Thread::current());
3002 
3003   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
3004   assert(pd != nullptr, "PcDesc must exist");
3005   for (ScopeDesc* sd = new ScopeDesc(this, pd);
3006        !sd->is_top(); sd = sd->sender()) {
3007     sd->verify();
3008   }
3009 }
3010 
3011 void nmethod::verify_scopes() {
3012   if( !method() ) return;       // Runtime stubs have no scope
3013   if (method()->is_native()) return; // Ignore stub methods.
3014   // iterate through all interrupt point
3015   // and verify the debug information is valid.
3016   RelocIterator iter(this);
3017   while (iter.next()) {
3018     address stub = nullptr;
3019     switch (iter.type()) {
3020       case relocInfo::virtual_call_type:
3021         verify_interrupt_point(iter.addr(), true /* is_inline_cache */);
3022         break;
3023       case relocInfo::opt_virtual_call_type:
3024         stub = iter.opt_virtual_call_reloc()->static_stub();
3025         verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3026         break;
3027       case relocInfo::static_call_type:
3028         stub = iter.static_call_reloc()->static_stub();
3029         verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3030         break;
3031       case relocInfo::runtime_call_type:
3032       case relocInfo::runtime_call_w_cp_type: {
3033         address destination = iter.reloc()->value();
3034         // Right now there is no way to find out which entries support
3035         // an interrupt point.  It would be nice if we had this
3036         // information in a table.
3037         break;
3038       }
3039       default:
3040         break;
3041     }
3042     assert(stub == nullptr || stub_contains(stub), "static call stub outside stub section");
3043   }
3044 }
3045 
3046 
3047 // -----------------------------------------------------------------------------
3048 // Printing operations
3049 
3050 void nmethod::print() const {
3051   ttyLocker ttyl;   // keep the following output all in one block
3052   print(tty);
3053 }
3054 
3055 void nmethod::print(outputStream* st) const {
3056   ResourceMark rm;
3057 
3058   st->print("Compiled method ");
3059 
3060   if (is_compiled_by_c1()) {
3061     st->print("(c1) ");
3062   } else if (is_compiled_by_c2()) {
3063     st->print("(c2) ");
3064   } else if (is_compiled_by_jvmci()) {
3065     st->print("(JVMCI) ");
3066   } else {
3067     st->print("(n/a) ");
3068   }
3069 
3070   print_on(st, nullptr);
3071 
3072   if (WizardMode) {
3073     st->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
3074     st->print(" for method " INTPTR_FORMAT , p2i(method()));
3075     st->print(" { ");
3076     st->print_cr("%s ", state());
3077     st->print_cr("}:");
3078   }
3079   if (size              () > 0) st->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3080                                              p2i(this),
3081                                              p2i(this) + size(),
3082                                              size());
3083   if (relocation_size   () > 0) st->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3084                                              p2i(relocation_begin()),
3085                                              p2i(relocation_end()),
3086                                              relocation_size());
3087   if (consts_size       () > 0) st->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3088                                              p2i(consts_begin()),
3089                                              p2i(consts_end()),
3090                                              consts_size());
3091   if (insts_size        () > 0) st->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3092                                              p2i(insts_begin()),
3093                                              p2i(insts_end()),
3094                                              insts_size());
3095   if (stub_size         () > 0) st->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3096                                              p2i(stub_begin()),
3097                                              p2i(stub_end()),
3098                                              stub_size());
3099   if (oops_size         () > 0) st->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3100                                              p2i(oops_begin()),
3101                                              p2i(oops_end()),
3102                                              oops_size());
3103   if (metadata_size     () > 0) st->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3104                                              p2i(metadata_begin()),
3105                                              p2i(metadata_end()),
3106                                              metadata_size());
3107 #if INCLUDE_JVMCI
3108   if (jvmci_data_size   () > 0) st->print_cr(" JVMCI data     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3109                                              p2i(jvmci_data_begin()),
3110                                              p2i(jvmci_data_end()),
3111                                              jvmci_data_size());
3112 #endif
3113   if (immutable_data_size() > 0) st->print_cr(" immutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3114                                              p2i(immutable_data_begin()),
3115                                              p2i(immutable_data_end()),
3116                                              immutable_data_size());
3117   if (dependencies_size () > 0) st->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3118                                              p2i(dependencies_begin()),
3119                                              p2i(dependencies_end()),
3120                                              dependencies_size());
3121   if (nul_chk_table_size() > 0) st->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3122                                              p2i(nul_chk_table_begin()),
3123                                              p2i(nul_chk_table_end()),
3124                                              nul_chk_table_size());
3125   if (handler_table_size() > 0) st->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3126                                              p2i(handler_table_begin()),
3127                                              p2i(handler_table_end()),
3128                                              handler_table_size());
3129   if (scopes_pcs_size   () > 0) st->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3130                                              p2i(scopes_pcs_begin()),
3131                                              p2i(scopes_pcs_end()),
3132                                              scopes_pcs_size());
3133   if (scopes_data_size  () > 0) st->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3134                                              p2i(scopes_data_begin()),
3135                                              p2i(scopes_data_end()),
3136                                              scopes_data_size());
3137 #if INCLUDE_JVMCI
3138   if (speculations_size () > 0) st->print_cr(" speculations   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3139                                              p2i(speculations_begin()),
3140                                              p2i(speculations_end()),
3141                                              speculations_size());
3142 #endif
3143 }
3144 
3145 void nmethod::print_code() {
3146   ResourceMark m;
3147   ttyLocker ttyl;
3148   // Call the specialized decode method of this class.
3149   decode(tty);
3150 }
3151 
3152 #ifndef PRODUCT  // called InstanceKlass methods are available only then. Declared as PRODUCT_RETURN
3153 
3154 void nmethod::print_dependencies_on(outputStream* out) {
3155   ResourceMark rm;
3156   stringStream st;
3157   st.print_cr("Dependencies:");
3158   for (Dependencies::DepStream deps(this); deps.next(); ) {
3159     deps.print_dependency(&st);
3160     InstanceKlass* ctxk = deps.context_type();
3161     if (ctxk != nullptr) {
3162       if (ctxk->is_dependent_nmethod(this)) {
3163         st.print_cr("   [nmethod<=klass]%s", ctxk->external_name());
3164       }
3165     }
3166     deps.log_dependency();  // put it into the xml log also
3167   }
3168   out->print_raw(st.as_string());
3169 }
3170 #endif
3171 
3172 #if defined(SUPPORT_DATA_STRUCTS)
3173 
3174 // Print the oops from the underlying CodeBlob.
3175 void nmethod::print_oops(outputStream* st) {
3176   ResourceMark m;
3177   st->print("Oops:");
3178   if (oops_begin() < oops_end()) {
3179     st->cr();
3180     for (oop* p = oops_begin(); p < oops_end(); p++) {
3181       Disassembler::print_location((unsigned char*)p, (unsigned char*)oops_begin(), (unsigned char*)oops_end(), st, true, false);
3182       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3183       if (Universe::contains_non_oop_word(p)) {
3184         st->print_cr("NON_OOP");
3185         continue;  // skip non-oops
3186       }
3187       if (*p == nullptr) {
3188         st->print_cr("nullptr-oop");
3189         continue;  // skip non-oops
3190       }
3191       (*p)->print_value_on(st);
3192       st->cr();
3193     }
3194   } else {
3195     st->print_cr(" <list empty>");
3196   }
3197 }
3198 
3199 // Print metadata pool.
3200 void nmethod::print_metadata(outputStream* st) {
3201   ResourceMark m;
3202   st->print("Metadata:");
3203   if (metadata_begin() < metadata_end()) {
3204     st->cr();
3205     for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
3206       Disassembler::print_location((unsigned char*)p, (unsigned char*)metadata_begin(), (unsigned char*)metadata_end(), st, true, false);
3207       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3208       if (*p && *p != Universe::non_oop_word()) {
3209         (*p)->print_value_on(st);
3210       }
3211       st->cr();
3212     }
3213   } else {
3214     st->print_cr(" <list empty>");
3215   }
3216 }
3217 
3218 #ifndef PRODUCT  // ScopeDesc::print_on() is available only then. Declared as PRODUCT_RETURN
3219 void nmethod::print_scopes_on(outputStream* st) {
3220   // Find the first pc desc for all scopes in the code and print it.
3221   ResourceMark rm;
3222   st->print("scopes:");
3223   if (scopes_pcs_begin() < scopes_pcs_end()) {
3224     st->cr();
3225     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3226       if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
3227         continue;
3228 
3229       ScopeDesc* sd = scope_desc_at(p->real_pc(this));
3230       while (sd != nullptr) {
3231         sd->print_on(st, p);  // print output ends with a newline
3232         sd = sd->sender();
3233       }
3234     }
3235   } else {
3236     st->print_cr(" <list empty>");
3237   }
3238 }
3239 #endif
3240 
3241 #ifndef PRODUCT  // RelocIterator does support printing only then.
3242 void nmethod::print_relocations() {
3243   ResourceMark m;       // in case methods get printed via the debugger
3244   tty->print_cr("relocations:");
3245   RelocIterator iter(this);
3246   iter.print();
3247 }
3248 #endif
3249 
3250 void nmethod::print_pcs_on(outputStream* st) {
3251   ResourceMark m;       // in case methods get printed via debugger
3252   st->print("pc-bytecode offsets:");
3253   if (scopes_pcs_begin() < scopes_pcs_end()) {
3254     st->cr();
3255     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3256       p->print_on(st, this);  // print output ends with a newline
3257     }
3258   } else {
3259     st->print_cr(" <list empty>");
3260   }
3261 }
3262 
3263 void nmethod::print_handler_table() {
3264   ExceptionHandlerTable(this).print(code_begin());
3265 }
3266 
3267 void nmethod::print_nul_chk_table() {
3268   ImplicitExceptionTable(this).print(code_begin());
3269 }
3270 
3271 void nmethod::print_recorded_oop(int log_n, int i) {
3272   void* value;
3273 
3274   if (i == 0) {
3275     value = nullptr;
3276   } else {
3277     // Be careful around non-oop words. Don't create an oop
3278     // with that value, or it will assert in verification code.
3279     if (Universe::contains_non_oop_word(oop_addr_at(i))) {
3280       value = Universe::non_oop_word();
3281     } else {
3282       value = oop_at(i);
3283     }
3284   }
3285 
3286   tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(value));
3287 
3288   if (value == Universe::non_oop_word()) {
3289     tty->print("non-oop word");
3290   } else {
3291     if (value == nullptr) {
3292       tty->print("nullptr-oop");
3293     } else {
3294       oop_at(i)->print_value_on(tty);
3295     }
3296   }
3297 
3298   tty->cr();
3299 }
3300 
3301 void nmethod::print_recorded_oops() {
3302   const int n = oops_count();
3303   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3304   tty->print("Recorded oops:");
3305   if (n > 0) {
3306     tty->cr();
3307     for (int i = 0; i < n; i++) {
3308       print_recorded_oop(log_n, i);
3309     }
3310   } else {
3311     tty->print_cr(" <list empty>");
3312   }
3313 }
3314 
3315 void nmethod::print_recorded_metadata() {
3316   const int n = metadata_count();
3317   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3318   tty->print("Recorded metadata:");
3319   if (n > 0) {
3320     tty->cr();
3321     for (int i = 0; i < n; i++) {
3322       Metadata* m = metadata_at(i);
3323       tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(m));
3324       if (m == (Metadata*)Universe::non_oop_word()) {
3325         tty->print("non-metadata word");
3326       } else if (m == nullptr) {
3327         tty->print("nullptr-oop");
3328       } else {
3329         Metadata::print_value_on_maybe_null(tty, m);
3330       }
3331       tty->cr();
3332     }
3333   } else {
3334     tty->print_cr(" <list empty>");
3335   }
3336 }
3337 #endif
3338 
3339 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
3340 
3341 void nmethod::print_constant_pool(outputStream* st) {
3342   //-----------------------------------
3343   //---<  Print the constant pool  >---
3344   //-----------------------------------
3345   int consts_size = this->consts_size();
3346   if ( consts_size > 0 ) {
3347     unsigned char* cstart = this->consts_begin();
3348     unsigned char* cp     = cstart;
3349     unsigned char* cend   = cp + consts_size;
3350     unsigned int   bytes_per_line = 4;
3351     unsigned int   CP_alignment   = 8;
3352     unsigned int   n;
3353 
3354     st->cr();
3355 
3356     //---<  print CP header to make clear what's printed  >---
3357     if( ((uintptr_t)cp&(CP_alignment-1)) == 0 ) {
3358       n = bytes_per_line;
3359       st->print_cr("[Constant Pool]");
3360       Disassembler::print_location(cp, cstart, cend, st, true, true);
3361       Disassembler::print_hexdata(cp, n, st, true);
3362       st->cr();
3363     } else {
3364       n = (int)((uintptr_t)cp & (bytes_per_line-1));
3365       st->print_cr("[Constant Pool (unaligned)]");
3366     }
3367 
3368     //---<  print CP contents, bytes_per_line at a time  >---
3369     while (cp < cend) {
3370       Disassembler::print_location(cp, cstart, cend, st, true, false);
3371       Disassembler::print_hexdata(cp, n, st, false);
3372       cp += n;
3373       n   = bytes_per_line;
3374       st->cr();
3375     }
3376 
3377     //---<  Show potential alignment gap between constant pool and code  >---
3378     cend = code_begin();
3379     if( cp < cend ) {
3380       n = 4;
3381       st->print_cr("[Code entry alignment]");
3382       while (cp < cend) {
3383         Disassembler::print_location(cp, cstart, cend, st, false, false);
3384         cp += n;
3385         st->cr();
3386       }
3387     }
3388   } else {
3389     st->print_cr("[Constant Pool (empty)]");
3390   }
3391   st->cr();
3392 }
3393 
3394 #endif
3395 
3396 // Disassemble this nmethod.
3397 // Print additional debug information, if requested. This could be code
3398 // comments, block comments, profiling counters, etc.
3399 // The undisassembled format is useful no disassembler library is available.
3400 // The resulting hex dump (with markers) can be disassembled later, or on
3401 // another system, when/where a disassembler library is available.
3402 void nmethod::decode2(outputStream* ost) const {
3403 
3404   // Called from frame::back_trace_with_decode without ResourceMark.
3405   ResourceMark rm;
3406 
3407   // Make sure we have a valid stream to print on.
3408   outputStream* st = ost ? ost : tty;
3409 
3410 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) && ! defined(SUPPORT_ASSEMBLY)
3411   const bool use_compressed_format    = true;
3412   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3413                                                                   AbstractDisassembler::show_block_comment());
3414 #else
3415   const bool use_compressed_format    = Disassembler::is_abstract();
3416   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3417                                                                   AbstractDisassembler::show_block_comment());
3418 #endif
3419 
3420   st->cr();
3421   this->print(st);
3422   st->cr();
3423 
3424 #if defined(SUPPORT_ASSEMBLY)
3425   //----------------------------------
3426   //---<  Print real disassembly  >---
3427   //----------------------------------
3428   if (! use_compressed_format) {
3429     st->print_cr("[Disassembly]");
3430     Disassembler::decode(const_cast<nmethod*>(this), st);
3431     st->bol();
3432     st->print_cr("[/Disassembly]");
3433     return;
3434   }
3435 #endif
3436 
3437 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3438 
3439   // Compressed undisassembled disassembly format.
3440   // The following status values are defined/supported:
3441   //   = 0 - currently at bol() position, nothing printed yet on current line.
3442   //   = 1 - currently at position after print_location().
3443   //   > 1 - in the midst of printing instruction stream bytes.
3444   int        compressed_format_idx    = 0;
3445   int        code_comment_column      = 0;
3446   const int  instr_maxlen             = Assembler::instr_maxlen();
3447   const uint tabspacing               = 8;
3448   unsigned char* start = this->code_begin();
3449   unsigned char* p     = this->code_begin();
3450   unsigned char* end   = this->code_end();
3451   unsigned char* pss   = p; // start of a code section (used for offsets)
3452 
3453   if ((start == nullptr) || (end == nullptr)) {
3454     st->print_cr("PrintAssembly not possible due to uninitialized section pointers");
3455     return;
3456   }
3457 #endif
3458 
3459 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3460   //---<  plain abstract disassembly, no comments or anything, just section headers  >---
3461   if (use_compressed_format && ! compressed_with_comments) {
3462     const_cast<nmethod*>(this)->print_constant_pool(st);
3463 
3464     //---<  Open the output (Marker for post-mortem disassembler)  >---
3465     st->print_cr("[MachCode]");
3466     const char* header = nullptr;
3467     address p0 = p;
3468     while (p < end) {
3469       address pp = p;
3470       while ((p < end) && (header == nullptr)) {
3471         header = nmethod_section_label(p);
3472         pp  = p;
3473         p  += Assembler::instr_len(p);
3474       }
3475       if (pp > p0) {
3476         AbstractDisassembler::decode_range_abstract(p0, pp, start, end, st, Assembler::instr_maxlen());
3477         p0 = pp;
3478         p  = pp;
3479         header = nullptr;
3480       } else if (header != nullptr) {
3481         st->bol();
3482         st->print_cr("%s", header);
3483         header = nullptr;
3484       }
3485     }
3486     //---<  Close the output (Marker for post-mortem disassembler)  >---
3487     st->bol();
3488     st->print_cr("[/MachCode]");
3489     return;
3490   }
3491 #endif
3492 
3493 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3494   //---<  abstract disassembly with comments and section headers merged in  >---
3495   if (compressed_with_comments) {
3496     const_cast<nmethod*>(this)->print_constant_pool(st);
3497 
3498     //---<  Open the output (Marker for post-mortem disassembler)  >---
3499     st->print_cr("[MachCode]");
3500     while ((p < end) && (p != nullptr)) {
3501       const int instruction_size_in_bytes = Assembler::instr_len(p);
3502 
3503       //---<  Block comments for nmethod. Interrupts instruction stream, if any.  >---
3504       // Outputs a bol() before and a cr() after, but only if a comment is printed.
3505       // Prints nmethod_section_label as well.
3506       if (AbstractDisassembler::show_block_comment()) {
3507         print_block_comment(st, p);
3508         if (st->position() == 0) {
3509           compressed_format_idx = 0;
3510         }
3511       }
3512 
3513       //---<  New location information after line break  >---
3514       if (compressed_format_idx == 0) {
3515         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
3516         compressed_format_idx = 1;
3517       }
3518 
3519       //---<  Code comment for current instruction. Address range [p..(p+len))  >---
3520       unsigned char* p_end = p + (ssize_t)instruction_size_in_bytes;
3521       S390_ONLY(if (p_end > end) p_end = end;) // avoid getting past the end
3522 
3523       if (AbstractDisassembler::show_comment() && const_cast<nmethod*>(this)->has_code_comment(p, p_end)) {
3524         //---<  interrupt instruction byte stream for code comment  >---
3525         if (compressed_format_idx > 1) {
3526           st->cr();  // interrupt byte stream
3527           st->cr();  // add an empty line
3528           code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
3529         }
3530         const_cast<nmethod*>(this)->print_code_comment_on(st, code_comment_column, p, p_end );
3531         st->bol();
3532         compressed_format_idx = 0;
3533       }
3534 
3535       //---<  New location information after line break  >---
3536       if (compressed_format_idx == 0) {
3537         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
3538         compressed_format_idx = 1;
3539       }
3540 
3541       //---<  Nicely align instructions for readability  >---
3542       if (compressed_format_idx > 1) {
3543         Disassembler::print_delimiter(st);
3544       }
3545 
3546       //---<  Now, finally, print the actual instruction bytes  >---
3547       unsigned char* p0 = p;
3548       p = Disassembler::decode_instruction_abstract(p, st, instruction_size_in_bytes, instr_maxlen);
3549       compressed_format_idx += (int)(p - p0);
3550 
3551       if (Disassembler::start_newline(compressed_format_idx-1)) {
3552         st->cr();
3553         compressed_format_idx = 0;
3554       }
3555     }
3556     //---<  Close the output (Marker for post-mortem disassembler)  >---
3557     st->bol();
3558     st->print_cr("[/MachCode]");
3559     return;
3560   }
3561 #endif
3562 }
3563 
3564 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
3565 
3566 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
3567   RelocIterator iter(this, begin, end);
3568   bool have_one = false;
3569   while (iter.next()) {
3570     have_one = true;
3571     switch (iter.type()) {
3572         case relocInfo::none:                  return "no_reloc";
3573         case relocInfo::oop_type: {
3574           // Get a non-resizable resource-allocated stringStream.
3575           // Our callees make use of (nested) ResourceMarks.
3576           stringStream st(NEW_RESOURCE_ARRAY(char, 1024), 1024);
3577           oop_Relocation* r = iter.oop_reloc();
3578           oop obj = r->oop_value();
3579           st.print("oop(");
3580           if (obj == nullptr) st.print("nullptr");
3581           else obj->print_value_on(&st);
3582           st.print(")");
3583           return st.as_string();
3584         }
3585         case relocInfo::metadata_type: {
3586           stringStream st;
3587           metadata_Relocation* r = iter.metadata_reloc();
3588           Metadata* obj = r->metadata_value();
3589           st.print("metadata(");
3590           if (obj == nullptr) st.print("nullptr");
3591           else obj->print_value_on(&st);
3592           st.print(")");
3593           return st.as_string();
3594         }
3595         case relocInfo::runtime_call_type:
3596         case relocInfo::runtime_call_w_cp_type: {
3597           stringStream st;
3598           st.print("runtime_call");
3599           CallRelocation* r = (CallRelocation*)iter.reloc();
3600           address dest = r->destination();
3601           CodeBlob* cb = CodeCache::find_blob(dest);
3602           if (cb != nullptr) {
3603             st.print(" %s", cb->name());
3604           } else {
3605             ResourceMark rm;
3606             const int buflen = 1024;
3607             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
3608             int offset;
3609             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
3610               st.print(" %s", buf);
3611               if (offset != 0) {
3612                 st.print("+%d", offset);
3613               }
3614             }
3615           }
3616           return st.as_string();
3617         }
3618         case relocInfo::virtual_call_type: {
3619           stringStream st;
3620           st.print_raw("virtual_call");
3621           virtual_call_Relocation* r = iter.virtual_call_reloc();
3622           Method* m = r->method_value();
3623           if (m != nullptr) {
3624             assert(m->is_method(), "");
3625             m->print_short_name(&st);
3626           }
3627           return st.as_string();
3628         }
3629         case relocInfo::opt_virtual_call_type: {
3630           stringStream st;
3631           st.print_raw("optimized virtual_call");
3632           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
3633           Method* m = r->method_value();
3634           if (m != nullptr) {
3635             assert(m->is_method(), "");
3636             m->print_short_name(&st);
3637           }
3638           return st.as_string();
3639         }
3640         case relocInfo::static_call_type: {
3641           stringStream st;
3642           st.print_raw("static_call");
3643           static_call_Relocation* r = iter.static_call_reloc();
3644           Method* m = r->method_value();
3645           if (m != nullptr) {
3646             assert(m->is_method(), "");
3647             m->print_short_name(&st);
3648           }
3649           return st.as_string();
3650         }
3651         case relocInfo::static_stub_type:      return "static_stub";
3652         case relocInfo::external_word_type:    return "external_word";
3653         case relocInfo::internal_word_type:    return "internal_word";
3654         case relocInfo::section_word_type:     return "section_word";
3655         case relocInfo::poll_type:             return "poll";
3656         case relocInfo::poll_return_type:      return "poll_return";
3657         case relocInfo::trampoline_stub_type:  return "trampoline_stub";
3658         case relocInfo::entry_guard_type:      return "entry_guard";
3659         case relocInfo::post_call_nop_type:    return "post_call_nop";
3660         case relocInfo::barrier_type: {
3661           barrier_Relocation* const reloc = iter.barrier_reloc();
3662           stringStream st;
3663           st.print("barrier format=%d", reloc->format());
3664           return st.as_string();
3665         }
3666 
3667         case relocInfo::type_mask:             return "type_bit_mask";
3668 
3669         default: {
3670           stringStream st;
3671           st.print("unknown relocInfo=%d", (int) iter.type());
3672           return st.as_string();
3673         }
3674     }
3675   }
3676   return have_one ? "other" : nullptr;
3677 }
3678 
3679 // Return the last scope in (begin..end]
3680 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
3681   PcDesc* p = pc_desc_near(begin+1);
3682   if (p != nullptr && p->real_pc(this) <= end) {
3683     return new ScopeDesc(this, p);
3684   }
3685   return nullptr;
3686 }
3687 
3688 const char* nmethod::nmethod_section_label(address pos) const {
3689   const char* label = nullptr;
3690   if (pos == code_begin())                                              label = "[Instructions begin]";
3691   if (pos == entry_point())                                             label = "[Entry Point]";
3692   if (pos == inline_entry_point())                                      label = "[Inline Entry Point]";
3693   if (pos == verified_entry_point())                                    label = "[Verified Entry Point]";
3694   if (pos == verified_inline_entry_point())                             label = "[Verified Inline Entry Point]";
3695   if (pos == verified_inline_ro_entry_point())                          label = "[Verified Inline Entry Point (RO)]";
3696   if (has_method_handle_invokes() && (pos == deopt_mh_handler_begin())) label = "[Deopt MH Handler Code]";
3697   if (pos == consts_begin() && pos != insts_begin())                    label = "[Constants]";
3698   // Check stub_code before checking exception_handler or deopt_handler.
3699   if (pos == this->stub_begin())                                        label = "[Stub Code]";
3700   if (JVMCI_ONLY(_exception_offset >= 0 &&) pos == exception_begin())          label = "[Exception Handler]";
3701   if (JVMCI_ONLY(_deopt_handler_offset != -1 &&) pos == deopt_handler_begin()) label = "[Deopt Handler Code]";
3702   return label;
3703 }
3704 
3705 static int maybe_print_entry_label(outputStream* stream, address pos, address entry, const char* label) {
3706   if (pos == entry) {
3707     stream->bol();
3708     stream->print_cr("%s", label);
3709     return 1;
3710   } else {
3711     return 0;
3712   }
3713 }
3714 
3715 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels) const {
3716   if (print_section_labels) {
3717     int n = 0;
3718     // Multiple entry points may be at the same position. Print them all.
3719     n += maybe_print_entry_label(stream, block_begin, entry_point(),                    "[Entry Point]");
3720     n += maybe_print_entry_label(stream, block_begin, inline_entry_point(),             "[Inline Entry Point]");
3721     n += maybe_print_entry_label(stream, block_begin, verified_entry_point(),           "[Verified Entry Point]");
3722     n += maybe_print_entry_label(stream, block_begin, verified_inline_entry_point(),    "[Verified Inline Entry Point]");
3723     n += maybe_print_entry_label(stream, block_begin, verified_inline_ro_entry_point(), "[Verified Inline Entry Point (RO)]");
3724     if (n == 0) {
3725       const char* label = nmethod_section_label(block_begin);
3726       if (label != nullptr) {
3727         stream->bol();
3728         stream->print_cr("%s", label);
3729       }
3730     }
3731   }
3732 
3733   Method* m = method();
3734   if (m == nullptr || is_osr_method()) {
3735     return;
3736   }
3737 
3738   // Print the name of the method (only once)
3739   address low = MIN4(entry_point(), verified_entry_point(), verified_inline_entry_point(), verified_inline_ro_entry_point());
3740   low = MIN2(low, inline_entry_point());
3741   assert(low != 0, "sanity");
3742   if (block_begin == low) {
3743     stream->print("  # ");
3744     m->print_value_on(stream);
3745     stream->cr();
3746   }
3747 
3748   // Print the arguments for the 3 types of verified entry points
3749   CompiledEntrySignature ces(m);
3750   ces.compute_calling_conventions(false);
3751   const GrowableArray<SigEntry>* sig_cc;
3752   const VMRegPair* regs;
3753   if (block_begin == verified_entry_point()) {
3754     sig_cc = ces.sig_cc();
3755     regs = ces.regs_cc();
3756   } else if (block_begin == verified_inline_entry_point()) {
3757     sig_cc = ces.sig();
3758     regs = ces.regs();
3759   } else if (block_begin == verified_inline_ro_entry_point()) {
3760     sig_cc = ces.sig_cc_ro();
3761     regs = ces.regs_cc_ro();
3762   } else {
3763     return;
3764   }
3765 
3766   bool has_this = !m->is_static();
3767   if (ces.has_inline_recv() && block_begin == verified_entry_point()) {
3768     // <this> argument is scalarized for verified_entry_point()
3769     has_this = false;
3770   }
3771   const char* spname = "sp"; // make arch-specific?
3772   int stack_slot_offset = this->frame_size() * wordSize;
3773   int tab1 = 14, tab2 = 24;
3774   int sig_index = 0;
3775   int arg_index = has_this ? -1 : 0;
3776   bool did_old_sp = false;
3777   for (ExtendedSignature sig = ExtendedSignature(sig_cc, SigEntryFilter()); !sig.at_end(); ++sig) {
3778     bool at_this = (arg_index == -1);
3779     bool at_old_sp = false;
3780     BasicType t = (*sig)._bt;
3781     if (at_this) {
3782       stream->print("  # this: ");
3783     } else {
3784       stream->print("  # parm%d: ", arg_index);
3785     }
3786     stream->move_to(tab1);
3787     VMReg fst = regs[sig_index].first();
3788     VMReg snd = regs[sig_index].second();
3789     if (fst->is_reg()) {
3790       stream->print("%s", fst->name());
3791       if (snd->is_valid())  {
3792         stream->print(":%s", snd->name());
3793       }
3794     } else if (fst->is_stack()) {
3795       int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
3796       if (offset == stack_slot_offset)  at_old_sp = true;
3797       stream->print("[%s+0x%x]", spname, offset);
3798     } else {
3799       stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
3800     }
3801     stream->print(" ");
3802     stream->move_to(tab2);
3803     stream->print("= ");
3804     if (at_this) {
3805       m->method_holder()->print_value_on(stream);
3806     } else {
3807       bool did_name = false;
3808       if (is_reference_type(t)) {
3809         Symbol* name = (*sig)._symbol;
3810         name->print_value_on(stream);
3811         did_name = true;
3812       }
3813       if (!did_name)
3814         stream->print("%s", type2name(t));
3815     }
3816     if (at_old_sp) {
3817       stream->print("  (%s of caller)", spname);
3818       did_old_sp = true;
3819     }
3820     stream->cr();
3821     sig_index += type2size[t];
3822     arg_index += 1;
3823   }
3824   if (!did_old_sp) {
3825     stream->print("  # ");
3826     stream->move_to(tab1);
3827     stream->print("[%s+0x%x]", spname, stack_slot_offset);
3828     stream->print("  (%s of caller)", spname);
3829     stream->cr();
3830   }
3831 }
3832 
3833 // Returns whether this nmethod has code comments.
3834 bool nmethod::has_code_comment(address begin, address end) {
3835   // scopes?
3836   ScopeDesc* sd  = scope_desc_in(begin, end);
3837   if (sd != nullptr) return true;
3838 
3839   // relocations?
3840   const char* str = reloc_string_for(begin, end);
3841   if (str != nullptr) return true;
3842 
3843   // implicit exceptions?
3844   int cont_offset = ImplicitExceptionTable(this).continuation_offset((uint)(begin - code_begin()));
3845   if (cont_offset != 0) return true;
3846 
3847   return false;
3848 }
3849 
3850 void nmethod::print_code_comment_on(outputStream* st, int column, address begin, address end) {
3851   ImplicitExceptionTable implicit_table(this);
3852   int pc_offset = (int)(begin - code_begin());
3853   int cont_offset = implicit_table.continuation_offset(pc_offset);
3854   bool oop_map_required = false;
3855   if (cont_offset != 0) {
3856     st->move_to(column, 6, 0);
3857     if (pc_offset == cont_offset) {
3858       st->print("; implicit exception: deoptimizes");
3859       oop_map_required = true;
3860     } else {
3861       st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
3862     }
3863   }
3864 
3865   // Find an oopmap in (begin, end].  We use the odd half-closed
3866   // interval so that oop maps and scope descs which are tied to the
3867   // byte after a call are printed with the call itself.  OopMaps
3868   // associated with implicit exceptions are printed with the implicit
3869   // instruction.
3870   address base = code_begin();
3871   ImmutableOopMapSet* oms = oop_maps();
3872   if (oms != nullptr) {
3873     for (int i = 0, imax = oms->count(); i < imax; i++) {
3874       const ImmutableOopMapPair* pair = oms->pair_at(i);
3875       const ImmutableOopMap* om = pair->get_from(oms);
3876       address pc = base + pair->pc_offset();
3877       if (pc >= begin) {
3878 #if INCLUDE_JVMCI
3879         bool is_implicit_deopt = implicit_table.continuation_offset(pair->pc_offset()) == (uint) pair->pc_offset();
3880 #else
3881         bool is_implicit_deopt = false;
3882 #endif
3883         if (is_implicit_deopt ? pc == begin : pc > begin && pc <= end) {
3884           st->move_to(column, 6, 0);
3885           st->print("; ");
3886           om->print_on(st);
3887           oop_map_required = false;
3888         }
3889       }
3890       if (pc > end) {
3891         break;
3892       }
3893     }
3894   }
3895   assert(!oop_map_required, "missed oopmap");
3896 
3897   Thread* thread = Thread::current();
3898 
3899   // Print any debug info present at this pc.
3900   ScopeDesc* sd  = scope_desc_in(begin, end);
3901   if (sd != nullptr) {
3902     st->move_to(column, 6, 0);
3903     if (sd->bci() == SynchronizationEntryBCI) {
3904       st->print(";*synchronization entry");
3905     } else if (sd->bci() == AfterBci) {
3906       st->print(";* method exit (unlocked if synchronized)");
3907     } else if (sd->bci() == UnwindBci) {
3908       st->print(";* unwind (locked if synchronized)");
3909     } else if (sd->bci() == AfterExceptionBci) {
3910       st->print(";* unwind (unlocked if synchronized)");
3911     } else if (sd->bci() == UnknownBci) {
3912       st->print(";* unknown");
3913     } else if (sd->bci() == InvalidFrameStateBci) {
3914       st->print(";* invalid frame state");
3915     } else {
3916       if (sd->method() == nullptr) {
3917         st->print("method is nullptr");
3918       } else if (sd->method()->is_native()) {
3919         st->print("method is native");
3920       } else {
3921         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
3922         st->print(";*%s", Bytecodes::name(bc));
3923         switch (bc) {
3924         case Bytecodes::_invokevirtual:
3925         case Bytecodes::_invokespecial:
3926         case Bytecodes::_invokestatic:
3927         case Bytecodes::_invokeinterface:
3928           {
3929             Bytecode_invoke invoke(methodHandle(thread, sd->method()), sd->bci());
3930             st->print(" ");
3931             if (invoke.name() != nullptr)
3932               invoke.name()->print_symbol_on(st);
3933             else
3934               st->print("<UNKNOWN>");
3935             break;
3936           }
3937         case Bytecodes::_getfield:
3938         case Bytecodes::_putfield:
3939         case Bytecodes::_getstatic:
3940         case Bytecodes::_putstatic:
3941           {
3942             Bytecode_field field(methodHandle(thread, sd->method()), sd->bci());
3943             st->print(" ");
3944             if (field.name() != nullptr)
3945               field.name()->print_symbol_on(st);
3946             else
3947               st->print("<UNKNOWN>");
3948           }
3949         default:
3950           break;
3951         }
3952       }
3953       st->print(" {reexecute=%d rethrow=%d return_oop=%d return_scalarized=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop(), sd->return_scalarized());
3954     }
3955 
3956     // Print all scopes
3957     for (;sd != nullptr; sd = sd->sender()) {
3958       st->move_to(column, 6, 0);
3959       st->print("; -");
3960       if (sd->should_reexecute()) {
3961         st->print(" (reexecute)");
3962       }
3963       if (sd->method() == nullptr) {
3964         st->print("method is nullptr");
3965       } else {
3966         sd->method()->print_short_name(st);
3967       }
3968       int lineno = sd->method()->line_number_from_bci(sd->bci());
3969       if (lineno != -1) {
3970         st->print("@%d (line %d)", sd->bci(), lineno);
3971       } else {
3972         st->print("@%d", sd->bci());
3973       }
3974       st->cr();
3975     }
3976   }
3977 
3978   // Print relocation information
3979   // Prevent memory leak: allocating without ResourceMark.
3980   ResourceMark rm;
3981   const char* str = reloc_string_for(begin, end);
3982   if (str != nullptr) {
3983     if (sd != nullptr) st->cr();
3984     st->move_to(column, 6, 0);
3985     st->print(";   {%s}", str);
3986   }
3987 }
3988 
3989 #endif
3990 
3991 address nmethod::call_instruction_address(address pc) const {
3992   if (NativeCall::is_call_before(pc)) {
3993     NativeCall *ncall = nativeCall_before(pc);
3994     return ncall->instruction_address();
3995   }
3996   return nullptr;
3997 }
3998 
3999 #if defined(SUPPORT_DATA_STRUCTS)
4000 void nmethod::print_value_on(outputStream* st) const {
4001   st->print("nmethod");
4002   print_on(st, nullptr);
4003 }
4004 #endif
4005 
4006 #ifndef PRODUCT
4007 
4008 void nmethod::print_calls(outputStream* st) {
4009   RelocIterator iter(this);
4010   while (iter.next()) {
4011     switch (iter.type()) {
4012     case relocInfo::virtual_call_type: {
4013       CompiledICLocker ml_verify(this);
4014       CompiledIC_at(&iter)->print();
4015       break;
4016     }
4017     case relocInfo::static_call_type:
4018     case relocInfo::opt_virtual_call_type:
4019       st->print_cr("Direct call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
4020       CompiledDirectCall::at(iter.reloc())->print();
4021       break;
4022     default:
4023       break;
4024     }
4025   }
4026 }
4027 
4028 void nmethod::print_statistics() {
4029   ttyLocker ttyl;
4030   if (xtty != nullptr)  xtty->head("statistics type='nmethod'");
4031   native_nmethod_stats.print_native_nmethod_stats();
4032 #ifdef COMPILER1
4033   c1_java_nmethod_stats.print_nmethod_stats("C1");
4034 #endif
4035 #ifdef COMPILER2
4036   c2_java_nmethod_stats.print_nmethod_stats("C2");
4037 #endif
4038 #if INCLUDE_JVMCI
4039   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
4040 #endif
4041   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
4042   DebugInformationRecorder::print_statistics();
4043   pc_nmethod_stats.print_pc_stats();
4044   Dependencies::print_statistics();
4045   ExternalsRecorder::print_statistics();
4046   if (xtty != nullptr)  xtty->tail("statistics");
4047 }
4048 
4049 #endif // !PRODUCT
4050 
4051 #if INCLUDE_JVMCI
4052 void nmethod::update_speculation(JavaThread* thread) {
4053   jlong speculation = thread->pending_failed_speculation();
4054   if (speculation != 0) {
4055     guarantee(jvmci_nmethod_data() != nullptr, "failed speculation in nmethod without failed speculation list");
4056     jvmci_nmethod_data()->add_failed_speculation(this, speculation);
4057     thread->set_pending_failed_speculation(0);
4058   }
4059 }
4060 
4061 const char* nmethod::jvmci_name() {
4062   if (jvmci_nmethod_data() != nullptr) {
4063     return jvmci_nmethod_data()->name();
4064   }
4065   return nullptr;
4066 }
4067 #endif