1 /*
   2  * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "asm/assembler.inline.hpp"
  26 #include "code/aotCodeCache.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/compilerDirectives.hpp"
  38 #include "compiler/compilerOracle.hpp"
  39 #include "compiler/compileTask.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/atomicAccess.hpp"
  64 #include "runtime/continuation.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/hashTable.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   guarantee(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 total_mut_size;
 132   uint relocation_size;
 133   uint consts_size;
 134   uint insts_size;
 135   uint stub_size;
 136   uint oops_size;
 137   uint metadata_size;
 138   uint dependencies_size;
 139   uint nul_chk_table_size;
 140   uint handler_table_size;
 141   uint scopes_pcs_size;
 142   uint scopes_data_size;
 143 #if INCLUDE_JVMCI
 144   uint speculations_size;
 145   uint jvmci_data_size;
 146 #endif
 147 
 148   void note_nmethod(nmethod* nm) {
 149     nmethod_count += 1;
 150     total_nm_size       += nm->size();
 151     total_immut_size    += nm->immutable_data_size();
 152     total_mut_size      += nm->mutable_data_size();
 153     relocation_size     += nm->relocation_size();
 154     consts_size         += nm->consts_size();
 155     insts_size          += nm->insts_size();
 156     stub_size           += nm->stub_size();
 157     oops_size           += nm->oops_size();
 158     metadata_size       += nm->metadata_size();
 159     scopes_data_size    += nm->scopes_data_size();
 160     scopes_pcs_size     += nm->scopes_pcs_size();
 161     dependencies_size   += nm->dependencies_size();
 162     handler_table_size  += nm->handler_table_size();
 163     nul_chk_table_size  += nm->nul_chk_table_size();
 164 #if INCLUDE_JVMCI
 165     speculations_size   += nm->speculations_size();
 166     jvmci_data_size     += nm->jvmci_data_size();
 167 #endif
 168   }
 169   void print_nmethod_stats(const char* name) {
 170     if (nmethod_count == 0)  return;
 171     tty->print_cr("Statistics for %u bytecoded nmethods for %s:", nmethod_count, name);
 172     uint total_size = total_nm_size + total_immut_size + total_mut_size;
 173     if (total_nm_size != 0) {
 174       tty->print_cr(" total size      = %u (100%%)", total_size);
 175       tty->print_cr(" in CodeCache    = %u (%f%%)", total_nm_size, (total_nm_size * 100.0f)/total_size);
 176     }
 177     uint header_size = (uint)(nmethod_count * sizeof(nmethod));
 178     if (nmethod_count != 0) {
 179       tty->print_cr("   header        = %u (%f%%)", header_size, (header_size * 100.0f)/total_nm_size);
 180     }
 181     if (consts_size != 0) {
 182       tty->print_cr("   constants     = %u (%f%%)", consts_size, (consts_size * 100.0f)/total_nm_size);
 183     }
 184     if (insts_size != 0) {
 185       tty->print_cr("   main code     = %u (%f%%)", insts_size, (insts_size * 100.0f)/total_nm_size);
 186     }
 187     if (stub_size != 0) {
 188       tty->print_cr("   stub code     = %u (%f%%)", stub_size, (stub_size * 100.0f)/total_nm_size);
 189     }
 190     if (oops_size != 0) {
 191       tty->print_cr("   oops          = %u (%f%%)", oops_size, (oops_size * 100.0f)/total_nm_size);
 192     }
 193     if (total_mut_size != 0) {
 194       tty->print_cr(" mutable data    = %u (%f%%)", total_mut_size, (total_mut_size * 100.0f)/total_size);
 195     }
 196     if (relocation_size != 0) {
 197       tty->print_cr("   relocation    = %u (%f%%)", relocation_size, (relocation_size * 100.0f)/total_mut_size);
 198     }
 199     if (metadata_size != 0) {
 200       tty->print_cr("   metadata      = %u (%f%%)", metadata_size, (metadata_size * 100.0f)/total_mut_size);
 201     }
 202 #if INCLUDE_JVMCI
 203     if (jvmci_data_size != 0) {
 204       tty->print_cr("   JVMCI data    = %u (%f%%)", jvmci_data_size, (jvmci_data_size * 100.0f)/total_mut_size);
 205     }
 206 #endif
 207     if (total_immut_size != 0) {
 208       tty->print_cr(" immutable data  = %u (%f%%)", total_immut_size, (total_immut_size * 100.0f)/total_size);
 209     }
 210     if (dependencies_size != 0) {
 211       tty->print_cr("   dependencies  = %u (%f%%)", dependencies_size, (dependencies_size * 100.0f)/total_immut_size);
 212     }
 213     if (nul_chk_table_size != 0) {
 214       tty->print_cr("   nul chk table = %u (%f%%)", nul_chk_table_size, (nul_chk_table_size * 100.0f)/total_immut_size);
 215     }
 216     if (handler_table_size != 0) {
 217       tty->print_cr("   handler table = %u (%f%%)", handler_table_size, (handler_table_size * 100.0f)/total_immut_size);
 218     }
 219     if (scopes_pcs_size != 0) {
 220       tty->print_cr("   scopes pcs    = %u (%f%%)", scopes_pcs_size, (scopes_pcs_size * 100.0f)/total_immut_size);
 221     }
 222     if (scopes_data_size != 0) {
 223       tty->print_cr("   scopes data   = %u (%f%%)", scopes_data_size, (scopes_data_size * 100.0f)/total_immut_size);
 224     }
 225 #if INCLUDE_JVMCI
 226     if (speculations_size != 0) {
 227       tty->print_cr("   speculations  = %u (%f%%)", speculations_size, (speculations_size * 100.0f)/total_immut_size);
 228     }
 229 #endif
 230   }
 231 };
 232 
 233 struct native_nmethod_stats_struct {
 234   uint native_nmethod_count;
 235   uint native_total_size;
 236   uint native_relocation_size;
 237   uint native_insts_size;
 238   uint native_oops_size;
 239   uint native_metadata_size;
 240   void note_native_nmethod(nmethod* nm) {
 241     native_nmethod_count += 1;
 242     native_total_size       += nm->size();
 243     native_relocation_size  += nm->relocation_size();
 244     native_insts_size       += nm->insts_size();
 245     native_oops_size        += nm->oops_size();
 246     native_metadata_size    += nm->metadata_size();
 247   }
 248   void print_native_nmethod_stats() {
 249     if (native_nmethod_count == 0)  return;
 250     tty->print_cr("Statistics for %u native nmethods:", native_nmethod_count);
 251     if (native_total_size != 0)       tty->print_cr(" N. total size  = %u", native_total_size);
 252     if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %u", native_relocation_size);
 253     if (native_insts_size != 0)       tty->print_cr(" N. main code   = %u", native_insts_size);
 254     if (native_oops_size != 0)        tty->print_cr(" N. oops        = %u", native_oops_size);
 255     if (native_metadata_size != 0)    tty->print_cr(" N. metadata    = %u", native_metadata_size);
 256   }
 257 };
 258 
 259 struct pc_nmethod_stats_struct {
 260   uint pc_desc_init;     // number of initialization of cache (= number of caches)
 261   uint pc_desc_queries;  // queries to nmethod::find_pc_desc
 262   uint pc_desc_approx;   // number of those which have approximate true
 263   uint pc_desc_repeats;  // number of _pc_descs[0] hits
 264   uint pc_desc_hits;     // number of LRU cache hits
 265   uint pc_desc_tests;    // total number of PcDesc examinations
 266   uint pc_desc_searches; // total number of quasi-binary search steps
 267   uint pc_desc_adds;     // number of LUR cache insertions
 268 
 269   void print_pc_stats() {
 270     tty->print_cr("PcDesc Statistics:  %u queries, %.2f comparisons per query",
 271                   pc_desc_queries,
 272                   (double)(pc_desc_tests + pc_desc_searches)
 273                   / pc_desc_queries);
 274     tty->print_cr("  caches=%d queries=%u/%u, hits=%u+%u, tests=%u+%u, adds=%u",
 275                   pc_desc_init,
 276                   pc_desc_queries, pc_desc_approx,
 277                   pc_desc_repeats, pc_desc_hits,
 278                   pc_desc_tests, pc_desc_searches, pc_desc_adds);
 279   }
 280 };
 281 
 282 #ifdef COMPILER1
 283 static java_nmethod_stats_struct c1_java_nmethod_stats;
 284 #endif
 285 #ifdef COMPILER2
 286 static java_nmethod_stats_struct c2_java_nmethod_stats;
 287 #endif
 288 #if INCLUDE_JVMCI
 289 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
 290 #endif
 291 static java_nmethod_stats_struct unknown_java_nmethod_stats;
 292 
 293 static native_nmethod_stats_struct native_nmethod_stats;
 294 static pc_nmethod_stats_struct pc_nmethod_stats;
 295 
 296 static void note_java_nmethod(nmethod* nm) {
 297 #ifdef COMPILER1
 298   if (nm->is_compiled_by_c1()) {
 299     c1_java_nmethod_stats.note_nmethod(nm);
 300   } else
 301 #endif
 302 #ifdef COMPILER2
 303   if (nm->is_compiled_by_c2()) {
 304     c2_java_nmethod_stats.note_nmethod(nm);
 305   } else
 306 #endif
 307 #if INCLUDE_JVMCI
 308   if (nm->is_compiled_by_jvmci()) {
 309     jvmci_java_nmethod_stats.note_nmethod(nm);
 310   } else
 311 #endif
 312   {
 313     unknown_java_nmethod_stats.note_nmethod(nm);
 314   }
 315 }
 316 #endif // !PRODUCT
 317 
 318 //---------------------------------------------------------------------------------
 319 
 320 
 321 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
 322   assert(pc != nullptr, "Must be non null");
 323   assert(exception.not_null(), "Must be non null");
 324   assert(handler != nullptr, "Must be non null");
 325 
 326   _count = 0;
 327   _exception_type = exception->klass();
 328   _next = nullptr;
 329   _purge_list_next = nullptr;
 330 
 331   add_address_and_handler(pc,handler);
 332 }
 333 
 334 
 335 address ExceptionCache::match(Handle exception, address pc) {
 336   assert(pc != nullptr,"Must be non null");
 337   assert(exception.not_null(),"Must be non null");
 338   if (exception->klass() == exception_type()) {
 339     return (test_address(pc));
 340   }
 341 
 342   return nullptr;
 343 }
 344 
 345 
 346 bool ExceptionCache::match_exception_with_space(Handle exception) {
 347   assert(exception.not_null(),"Must be non null");
 348   if (exception->klass() == exception_type() && count() < cache_size) {
 349     return true;
 350   }
 351   return false;
 352 }
 353 
 354 
 355 address ExceptionCache::test_address(address addr) {
 356   int limit = count();
 357   for (int i = 0; i < limit; i++) {
 358     if (pc_at(i) == addr) {
 359       return handler_at(i);
 360     }
 361   }
 362   return nullptr;
 363 }
 364 
 365 
 366 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
 367   if (test_address(addr) == handler) return true;
 368 
 369   int index = count();
 370   if (index < cache_size) {
 371     set_pc_at(index, addr);
 372     set_handler_at(index, handler);
 373     increment_count();
 374     return true;
 375   }
 376   return false;
 377 }
 378 
 379 ExceptionCache* ExceptionCache::next() {
 380   return AtomicAccess::load(&_next);
 381 }
 382 
 383 void ExceptionCache::set_next(ExceptionCache *ec) {
 384   AtomicAccess::store(&_next, ec);
 385 }
 386 
 387 //-----------------------------------------------------------------------------
 388 
 389 
 390 // Helper used by both find_pc_desc methods.
 391 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
 392   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
 393   if (!approximate) {
 394     return pc->pc_offset() == pc_offset;
 395   } else {
 396     // Do not look before the sentinel
 397     assert(pc_offset > PcDesc::lower_offset_limit, "illegal pc_offset");
 398     return pc_offset <= pc->pc_offset() && (pc-1)->pc_offset() < pc_offset;
 399   }
 400 }
 401 
 402 void PcDescCache::init_to(PcDesc* initial_pc_desc) {
 403   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_init);
 404   // initialize the cache by filling it with benign (non-null) values
 405   assert(initial_pc_desc != nullptr && initial_pc_desc->pc_offset() == PcDesc::lower_offset_limit,
 406          "must start with a sentinel");
 407   for (int i = 0; i < cache_size; i++) {
 408     _pc_descs[i] = initial_pc_desc;
 409   }
 410 }
 411 
 412 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
 413   // Note: one might think that caching the most recently
 414   // read value separately would be a win, but one would be
 415   // wrong.  When many threads are updating it, the cache
 416   // line it's in would bounce between caches, negating
 417   // any benefit.
 418 
 419   // In order to prevent race conditions do not load cache elements
 420   // repeatedly, but use a local copy:
 421   PcDesc* res;
 422 
 423   // Step one:  Check the most recently added value.
 424   res = _pc_descs[0];
 425   assert(res != nullptr, "PcDesc cache should be initialized already");
 426 
 427   // Approximate only here since PcDescContainer::find_pc_desc() checked for exact case.
 428   if (approximate && match_desc(res, pc_offset, approximate)) {
 429     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
 430     return res;
 431   }
 432 
 433   // Step two:  Check the rest of the LRU cache.
 434   for (int i = 1; i < cache_size; ++i) {
 435     res = _pc_descs[i];
 436     if (res->pc_offset() < 0) break;  // optimization: skip empty cache
 437     if (match_desc(res, pc_offset, approximate)) {
 438       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
 439       return res;
 440     }
 441   }
 442 
 443   // Report failure.
 444   return nullptr;
 445 }
 446 
 447 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
 448   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
 449   // Update the LRU cache by shifting pc_desc forward.
 450   for (int i = 0; i < cache_size; i++)  {
 451     PcDesc* next = _pc_descs[i];
 452     _pc_descs[i] = pc_desc;
 453     pc_desc = next;
 454   }
 455 }
 456 
 457 // adjust pcs_size so that it is a multiple of both oopSize and
 458 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
 459 // of oopSize, then 2*sizeof(PcDesc) is)
 460 static int adjust_pcs_size(int pcs_size) {
 461   int nsize = align_up(pcs_size,   oopSize);
 462   if ((nsize % sizeof(PcDesc)) != 0) {
 463     nsize = pcs_size + sizeof(PcDesc);
 464   }
 465   assert((nsize % oopSize) == 0, "correct alignment");
 466   return nsize;
 467 }
 468 
 469 // Returns a string version of the method state.
 470 const char* nmethod::state() const {
 471   int state = get_state();
 472   switch (state) {
 473   case not_installed:
 474     return "not installed";
 475   case in_use:
 476     return "in use";
 477   case not_entrant:
 478     return "not_entrant";
 479   default:
 480     fatal("unexpected method state: %d", state);
 481     return nullptr;
 482   }
 483 }
 484 
 485 void nmethod::set_deoptimized_done() {
 486   ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
 487   if (_deoptimization_status != deoptimize_done) { // can't go backwards
 488     AtomicAccess::store(&_deoptimization_status, deoptimize_done);
 489   }
 490 }
 491 
 492 ExceptionCache* nmethod::exception_cache_acquire() const {
 493   return AtomicAccess::load_acquire(&_exception_cache);
 494 }
 495 
 496 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
 497   assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
 498   assert(new_entry != nullptr,"Must be non null");
 499   assert(new_entry->next() == nullptr, "Must be null");
 500 
 501   for (;;) {
 502     ExceptionCache *ec = exception_cache();
 503     if (ec != nullptr) {
 504       Klass* ex_klass = ec->exception_type();
 505       if (!ex_klass->is_loader_alive()) {
 506         // We must guarantee that entries are not inserted with new next pointer
 507         // edges to ExceptionCache entries with dead klasses, due to bad interactions
 508         // with concurrent ExceptionCache cleanup. Therefore, the inserts roll
 509         // the head pointer forward to the first live ExceptionCache, so that the new
 510         // next pointers always point at live ExceptionCaches, that are not removed due
 511         // to concurrent ExceptionCache cleanup.
 512         ExceptionCache* next = ec->next();
 513         if (AtomicAccess::cmpxchg(&_exception_cache, ec, next) == ec) {
 514           CodeCache::release_exception_cache(ec);
 515         }
 516         continue;
 517       }
 518       ec = exception_cache();
 519       if (ec != nullptr) {
 520         new_entry->set_next(ec);
 521       }
 522     }
 523     if (AtomicAccess::cmpxchg(&_exception_cache, ec, new_entry) == ec) {
 524       return;
 525     }
 526   }
 527 }
 528 
 529 void nmethod::clean_exception_cache() {
 530   // For each nmethod, only a single thread may call this cleanup function
 531   // at the same time, whether called in STW cleanup or concurrent cleanup.
 532   // Note that if the GC is processing exception cache cleaning in a concurrent phase,
 533   // then a single writer may contend with cleaning up the head pointer to the
 534   // first ExceptionCache node that has a Klass* that is alive. That is fine,
 535   // as long as there is no concurrent cleanup of next pointers from concurrent writers.
 536   // And the concurrent writers do not clean up next pointers, only the head.
 537   // Also note that concurrent readers will walk through Klass* pointers that are not
 538   // alive. That does not cause ABA problems, because Klass* is deleted after
 539   // a handshake with all threads, after all stale ExceptionCaches have been
 540   // unlinked. That is also when the CodeCache::exception_cache_purge_list()
 541   // is deleted, with all ExceptionCache entries that were cleaned concurrently.
 542   // That similarly implies that CAS operations on ExceptionCache entries do not
 543   // suffer from ABA problems as unlinking and deletion is separated by a global
 544   // handshake operation.
 545   ExceptionCache* prev = nullptr;
 546   ExceptionCache* curr = exception_cache_acquire();
 547 
 548   while (curr != nullptr) {
 549     ExceptionCache* next = curr->next();
 550 
 551     if (!curr->exception_type()->is_loader_alive()) {
 552       if (prev == nullptr) {
 553         // Try to clean head; this is contended by concurrent inserts, that
 554         // both lazily clean the head, and insert entries at the head. If
 555         // the CAS fails, the operation is restarted.
 556         if (AtomicAccess::cmpxchg(&_exception_cache, curr, next) != curr) {
 557           prev = nullptr;
 558           curr = exception_cache_acquire();
 559           continue;
 560         }
 561       } else {
 562         // It is impossible to during cleanup connect the next pointer to
 563         // an ExceptionCache that has not been published before a safepoint
 564         // prior to the cleanup. Therefore, release is not required.
 565         prev->set_next(next);
 566       }
 567       // prev stays the same.
 568 
 569       CodeCache::release_exception_cache(curr);
 570     } else {
 571       prev = curr;
 572     }
 573 
 574     curr = next;
 575   }
 576 }
 577 
 578 // public method for accessing the exception cache
 579 // These are the public access methods.
 580 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
 581   // We never grab a lock to read the exception cache, so we may
 582   // have false negatives. This is okay, as it can only happen during
 583   // the first few exception lookups for a given nmethod.
 584   ExceptionCache* ec = exception_cache_acquire();
 585   while (ec != nullptr) {
 586     address ret_val;
 587     if ((ret_val = ec->match(exception,pc)) != nullptr) {
 588       return ret_val;
 589     }
 590     ec = ec->next();
 591   }
 592   return nullptr;
 593 }
 594 
 595 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
 596   // There are potential race conditions during exception cache updates, so we
 597   // must own the ExceptionCache_lock before doing ANY modifications. Because
 598   // we don't lock during reads, it is possible to have several threads attempt
 599   // to update the cache with the same data. We need to check for already inserted
 600   // copies of the current data before adding it.
 601 
 602   MutexLocker ml(ExceptionCache_lock);
 603   ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
 604 
 605   if (target_entry == nullptr || !target_entry->add_address_and_handler(pc,handler)) {
 606     target_entry = new ExceptionCache(exception,pc,handler);
 607     add_exception_cache_entry(target_entry);
 608   }
 609 }
 610 
 611 // private method for handling exception cache
 612 // These methods are private, and used to manipulate the exception cache
 613 // directly.
 614 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
 615   ExceptionCache* ec = exception_cache_acquire();
 616   while (ec != nullptr) {
 617     if (ec->match_exception_with_space(exception)) {
 618       return ec;
 619     }
 620     ec = ec->next();
 621   }
 622   return nullptr;
 623 }
 624 
 625 bool nmethod::is_at_poll_return(address pc) {
 626   RelocIterator iter(this, pc, pc+1);
 627   while (iter.next()) {
 628     if (iter.type() == relocInfo::poll_return_type)
 629       return true;
 630   }
 631   return false;
 632 }
 633 
 634 
 635 bool nmethod::is_at_poll_or_poll_return(address pc) {
 636   RelocIterator iter(this, pc, pc+1);
 637   while (iter.next()) {
 638     relocInfo::relocType t = iter.type();
 639     if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
 640       return true;
 641   }
 642   return false;
 643 }
 644 
 645 void nmethod::verify_oop_relocations() {
 646   // Ensure sure that the code matches the current oop values
 647   RelocIterator iter(this, nullptr, nullptr);
 648   while (iter.next()) {
 649     if (iter.type() == relocInfo::oop_type) {
 650       oop_Relocation* reloc = iter.oop_reloc();
 651       if (!reloc->oop_is_immediate()) {
 652         reloc->verify_oop_relocation();
 653       }
 654     }
 655   }
 656 }
 657 
 658 
 659 ScopeDesc* nmethod::scope_desc_at(address pc) {
 660   PcDesc* pd = pc_desc_at(pc);
 661   guarantee(pd != nullptr, "scope must be present");
 662   return new ScopeDesc(this, pd);
 663 }
 664 
 665 ScopeDesc* nmethod::scope_desc_near(address pc) {
 666   PcDesc* pd = pc_desc_near(pc);
 667   guarantee(pd != nullptr, "scope must be present");
 668   return new ScopeDesc(this, pd);
 669 }
 670 
 671 address nmethod::oops_reloc_begin() const {
 672   // If the method is not entrant then a JMP is plastered over the
 673   // first few bytes.  If an oop in the old code was there, that oop
 674   // should not get GC'd.  Skip the first few bytes of oops on
 675   // not-entrant methods.
 676   if (frame_complete_offset() != CodeOffsets::frame_never_safe &&
 677       code_begin() + frame_complete_offset() >
 678       verified_entry_point() + NativeJump::instruction_size)
 679   {
 680     // If we have a frame_complete_offset after the native jump, then there
 681     // is no point trying to look for oops before that. This is a requirement
 682     // for being allowed to scan oops concurrently.
 683     return code_begin() + frame_complete_offset();
 684   }
 685 
 686   address low_boundary = verified_entry_point();
 687   return low_boundary;
 688 }
 689 
 690 // Method that knows how to preserve outgoing arguments at call. This method must be
 691 // called with a frame corresponding to a Java invoke
 692 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
 693   if (method() == nullptr) {
 694     return;
 695   }
 696 
 697   // handle the case of an anchor explicitly set in continuation code that doesn't have a callee
 698   JavaThread* thread = reg_map->thread();
 699   if ((thread->has_last_Java_frame() && fr.sp() == thread->last_Java_sp())
 700       JVMTI_ONLY(|| (method()->is_continuation_enter_intrinsic() && thread->on_monitor_waited_event()))) {
 701     return;
 702   }
 703 
 704   if (!method()->is_native()) {
 705     address pc = fr.pc();
 706     bool has_receiver, has_appendix;
 707     Symbol* signature;
 708 
 709     // The method attached by JIT-compilers should be used, if present.
 710     // Bytecode can be inaccurate in such case.
 711     Method* callee = attached_method_before_pc(pc);
 712     if (callee != nullptr) {
 713       has_receiver = !(callee->access_flags().is_static());
 714       has_appendix = false;
 715       signature    = callee->signature();
 716     } else {
 717       SimpleScopeDesc ssd(this, pc);
 718 
 719       Bytecode_invoke call(methodHandle(Thread::current(), ssd.method()), ssd.bci());
 720       has_receiver = call.has_receiver();
 721       has_appendix = call.has_appendix();
 722       signature    = call.signature();
 723     }
 724 
 725     fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
 726   } else if (method()->is_continuation_enter_intrinsic()) {
 727     // This method only calls Continuation.enter()
 728     Symbol* signature = vmSymbols::continuationEnter_signature();
 729     fr.oops_compiled_arguments_do(signature, false, false, reg_map, f);
 730   }
 731 }
 732 
 733 Method* nmethod::attached_method(address call_instr) {
 734   assert(code_contains(call_instr), "not part of the nmethod");
 735   RelocIterator iter(this, call_instr, call_instr + 1);
 736   while (iter.next()) {
 737     if (iter.addr() == call_instr) {
 738       switch(iter.type()) {
 739         case relocInfo::static_call_type:      return iter.static_call_reloc()->method_value();
 740         case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
 741         case relocInfo::virtual_call_type:     return iter.virtual_call_reloc()->method_value();
 742         default:                               break;
 743       }
 744     }
 745   }
 746   return nullptr; // not found
 747 }
 748 
 749 Method* nmethod::attached_method_before_pc(address pc) {
 750   if (NativeCall::is_call_before(pc)) {
 751     NativeCall* ncall = nativeCall_before(pc);
 752     return attached_method(ncall->instruction_address());
 753   }
 754   return nullptr; // not a call
 755 }
 756 
 757 void nmethod::clear_inline_caches() {
 758   assert(SafepointSynchronize::is_at_safepoint() || (NMethodState_lock->owned_by_self() && is_not_installed()), "clearing of IC's only allowed at safepoint or when not installed");
 759   RelocIterator iter(this);
 760   while (iter.next()) {
 761     iter.reloc()->clear_inline_cache();
 762   }
 763 }
 764 
 765 #ifdef ASSERT
 766 // Check class_loader is alive for this bit of metadata.
 767 class CheckClass : public MetadataClosure {
 768   void do_metadata(Metadata* md) {
 769     Klass* klass = nullptr;
 770     if (md->is_klass()) {
 771       klass = ((Klass*)md);
 772     } else if (md->is_method()) {
 773       klass = ((Method*)md)->method_holder();
 774     } else if (md->is_methodData()) {
 775       klass = ((MethodData*)md)->method()->method_holder();
 776     } else if (md->is_methodCounters()) {
 777       klass = ((MethodCounters*)md)->method()->method_holder();
 778     } else {
 779       md->print();
 780       ShouldNotReachHere();
 781     }
 782     assert(klass->is_loader_alive(), "must be alive");
 783   }
 784 };
 785 #endif // ASSERT
 786 
 787 // Clean references to unloaded nmethods at addr from this one, which is not unloaded.
 788 template <typename CallsiteT>
 789 static void clean_if_nmethod_is_unloaded(CallsiteT* callsite, bool clean_all) {
 790   CodeBlob* cb = CodeCache::find_blob(callsite->destination());
 791   if (!cb->is_nmethod()) {
 792     return;
 793   }
 794   nmethod* nm = cb->as_nmethod();
 795   if (clean_all || !nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
 796     callsite->set_to_clean();
 797   }
 798 }
 799 
 800 // Cleans caches in nmethods that point to either classes that are unloaded
 801 // or nmethods that are unloaded.
 802 //
 803 // Can be called either in parallel by G1 currently or after all
 804 // nmethods are unloaded.  Return postponed=true in the parallel case for
 805 // inline caches found that point to nmethods that are not yet visited during
 806 // the do_unloading walk.
 807 void nmethod::unload_nmethod_caches(bool unloading_occurred) {
 808   ResourceMark rm;
 809 
 810   // Exception cache only needs to be called if unloading occurred
 811   if (unloading_occurred) {
 812     clean_exception_cache();
 813   }
 814 
 815   cleanup_inline_caches_impl(unloading_occurred, false);
 816 
 817 #ifdef ASSERT
 818   // Check that the metadata embedded in the nmethod is alive
 819   CheckClass check_class;
 820   metadata_do(&check_class);
 821 #endif
 822 }
 823 
 824 void nmethod::run_nmethod_entry_barrier() {
 825   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
 826   if (bs_nm != nullptr) {
 827     // We want to keep an invariant that nmethods found through iterations of a Thread's
 828     // nmethods found in safepoints have gone through an entry barrier and are not armed.
 829     // By calling this nmethod entry barrier, it plays along and acts
 830     // like any other nmethod found on the stack of a thread (fewer surprises).
 831     nmethod* nm = this;
 832     bool alive = bs_nm->nmethod_entry_barrier(nm);
 833     assert(alive, "should be alive");
 834   }
 835 }
 836 
 837 // Only called by whitebox test
 838 void nmethod::cleanup_inline_caches_whitebox() {
 839   assert_locked_or_safepoint(CodeCache_lock);
 840   CompiledICLocker ic_locker(this);
 841   cleanup_inline_caches_impl(false /* unloading_occurred */, true /* clean_all */);
 842 }
 843 
 844 address* nmethod::orig_pc_addr(const frame* fr) {
 845   return (address*) ((address)fr->unextended_sp() + orig_pc_offset());
 846 }
 847 
 848 // Called to clean up after class unloading for live nmethods
 849 void nmethod::cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all) {
 850   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
 851   ResourceMark rm;
 852 
 853   // Find all calls in an nmethod and clear the ones that point to bad nmethods.
 854   RelocIterator iter(this, oops_reloc_begin());
 855   bool is_in_static_stub = false;
 856   while(iter.next()) {
 857 
 858     switch (iter.type()) {
 859 
 860     case relocInfo::virtual_call_type:
 861       if (unloading_occurred) {
 862         // If class unloading occurred we first clear ICs where the cached metadata
 863         // is referring to an unloaded klass or method.
 864         CompiledIC_at(&iter)->clean_metadata();
 865       }
 866 
 867       clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), clean_all);
 868       break;
 869 
 870     case relocInfo::opt_virtual_call_type:
 871     case relocInfo::static_call_type:
 872       clean_if_nmethod_is_unloaded(CompiledDirectCall::at(iter.reloc()), clean_all);
 873       break;
 874 
 875     case relocInfo::static_stub_type: {
 876       is_in_static_stub = true;
 877       break;
 878     }
 879 
 880     case relocInfo::metadata_type: {
 881       // Only the metadata relocations contained in static/opt virtual call stubs
 882       // contains the Method* passed to c2i adapters. It is the only metadata
 883       // relocation that needs to be walked, as it is the one metadata relocation
 884       // that violates the invariant that all metadata relocations have an oop
 885       // in the compiled method (due to deferred resolution and code patching).
 886 
 887       // This causes dead metadata to remain in compiled methods that are not
 888       // unloading. Unless these slippery metadata relocations of the static
 889       // stubs are at least cleared, subsequent class redefinition operations
 890       // will access potentially free memory, and JavaThread execution
 891       // concurrent to class unloading may call c2i adapters with dead methods.
 892       if (!is_in_static_stub) {
 893         // The first metadata relocation after a static stub relocation is the
 894         // metadata relocation of the static stub used to pass the Method* to
 895         // c2i adapters.
 896         continue;
 897       }
 898       is_in_static_stub = false;
 899       if (is_unloading()) {
 900         // If the nmethod itself is dying, then it may point at dead metadata.
 901         // Nobody should follow that metadata; it is strictly unsafe.
 902         continue;
 903       }
 904       metadata_Relocation* r = iter.metadata_reloc();
 905       Metadata* md = r->metadata_value();
 906       if (md != nullptr && md->is_method()) {
 907         Method* method = static_cast<Method*>(md);
 908         if (!method->method_holder()->is_loader_alive()) {
 909           AtomicAccess::store(r->metadata_addr(), (Method*)nullptr);
 910 
 911           if (!r->metadata_is_immediate()) {
 912             r->fix_metadata_relocation();
 913           }
 914         }
 915       }
 916       break;
 917     }
 918 
 919     default:
 920       break;
 921     }
 922   }
 923 }
 924 
 925 address nmethod::continuation_for_implicit_exception(address pc, bool for_div0_check) {
 926   // Exception happened outside inline-cache check code => we are inside
 927   // an active nmethod => use cpc to determine a return address
 928   int exception_offset = int(pc - code_begin());
 929   int cont_offset = ImplicitExceptionTable(this).continuation_offset( exception_offset );
 930 #ifdef ASSERT
 931   if (cont_offset == 0) {
 932     Thread* thread = Thread::current();
 933     ResourceMark rm(thread);
 934     CodeBlob* cb = CodeCache::find_blob(pc);
 935     assert(cb != nullptr && cb == this, "");
 936 
 937     // Keep tty output consistent. To avoid ttyLocker, we buffer in stream, and print all at once.
 938     stringStream ss;
 939     ss.print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
 940     print_on(&ss);
 941     method()->print_codes_on(&ss);
 942     print_code_on(&ss);
 943     print_pcs_on(&ss);
 944     tty->print("%s", ss.as_string()); // print all at once
 945   }
 946 #endif
 947   if (cont_offset == 0) {
 948     // Let the normal error handling report the exception
 949     return nullptr;
 950   }
 951   if (cont_offset == exception_offset) {
 952 #if INCLUDE_JVMCI
 953     Deoptimization::DeoptReason deopt_reason = for_div0_check ? Deoptimization::Reason_div0_check : Deoptimization::Reason_null_check;
 954     JavaThread *thread = JavaThread::current();
 955     thread->set_jvmci_implicit_exception_pc(pc);
 956     thread->set_pending_deoptimization(Deoptimization::make_trap_request(deopt_reason,
 957                                                                          Deoptimization::Action_reinterpret));
 958     return (SharedRuntime::deopt_blob()->implicit_exception_uncommon_trap());
 959 #else
 960     ShouldNotReachHere();
 961 #endif
 962   }
 963   return code_begin() + cont_offset;
 964 }
 965 
 966 class HasEvolDependency : public MetadataClosure {
 967   bool _has_evol_dependency;
 968  public:
 969   HasEvolDependency() : _has_evol_dependency(false) {}
 970   void do_metadata(Metadata* md) {
 971     if (md->is_method()) {
 972       Method* method = (Method*)md;
 973       if (method->is_old()) {
 974         _has_evol_dependency = true;
 975       }
 976     }
 977   }
 978   bool has_evol_dependency() const { return _has_evol_dependency; }
 979 };
 980 
 981 bool nmethod::has_evol_metadata() {
 982   // Check the metadata in relocIter and CompiledIC and also deoptimize
 983   // any nmethod that has reference to old methods.
 984   HasEvolDependency check_evol;
 985   metadata_do(&check_evol);
 986   if (check_evol.has_evol_dependency() && log_is_enabled(Debug, redefine, class, nmethod)) {
 987     ResourceMark rm;
 988     log_debug(redefine, class, nmethod)
 989             ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on in nmethod metadata",
 990              _method->method_holder()->external_name(),
 991              _method->name()->as_C_string(),
 992              _method->signature()->as_C_string(),
 993              compile_id());
 994   }
 995   return check_evol.has_evol_dependency();
 996 }
 997 
 998 int nmethod::total_size() const {
 999   return
1000     consts_size()        +
1001     insts_size()         +
1002     stub_size()          +
1003     scopes_data_size()   +
1004     scopes_pcs_size()    +
1005     handler_table_size() +
1006     nul_chk_table_size();
1007 }
1008 
1009 const char* nmethod::compile_kind() const {
1010   if (is_osr_method()) return "osr";
1011   if (preloaded())     return "AP";
1012   if (is_aot())        return "A";
1013 
1014   if (method() != nullptr && is_native_method()) {
1015     if (method()->is_continuation_native_intrinsic()) {
1016       return "cnt";
1017     }
1018     return "c2n";
1019   }
1020   return nullptr;
1021 }
1022 
1023 const char* nmethod::compiler_name() const {
1024   return compilertype2name(_compiler_type);
1025 }
1026 
1027 #ifdef ASSERT
1028 class CheckForOopsClosure : public OopClosure {
1029   bool _found_oop = false;
1030  public:
1031   virtual void do_oop(oop* o) { _found_oop = true; }
1032   virtual void do_oop(narrowOop* o) { _found_oop = true; }
1033   bool found_oop() { return _found_oop; }
1034 };
1035 class CheckForMetadataClosure : public MetadataClosure {
1036   bool _found_metadata = false;
1037   Metadata* _ignore = nullptr;
1038  public:
1039   CheckForMetadataClosure(Metadata* ignore) : _ignore(ignore) {}
1040   virtual void do_metadata(Metadata* md) { if (md != _ignore) _found_metadata = true; }
1041   bool found_metadata() { return _found_metadata; }
1042 };
1043 
1044 static void assert_no_oops_or_metadata(nmethod* nm) {
1045   if (nm == nullptr) return;
1046   assert(nm->oop_maps() == nullptr, "expectation");
1047 
1048   CheckForOopsClosure cfo;
1049   nm->oops_do(&cfo);
1050   assert(!cfo.found_oop(), "no oops allowed");
1051 
1052   // We allow an exception for the own Method, but require its class to be permanent.
1053   Method* own_method = nm->method();
1054   CheckForMetadataClosure cfm(/* ignore reference to own Method */ own_method);
1055   nm->metadata_do(&cfm);
1056   assert(!cfm.found_metadata(), "no metadata allowed");
1057 
1058   assert(own_method->method_holder()->class_loader_data()->is_permanent_class_loader_data(),
1059          "Method's class needs to be permanent");
1060 }
1061 #endif
1062 
1063 static int required_mutable_data_size(CodeBuffer* code_buffer,
1064                                       int jvmci_data_size = 0) {
1065   return align_up(code_buffer->total_relocation_size(), oopSize) +
1066          align_up(code_buffer->total_metadata_size(), oopSize) +
1067          align_up(jvmci_data_size, oopSize);
1068 }
1069 
1070 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
1071   int compile_id,
1072   CodeBuffer *code_buffer,
1073   int vep_offset,
1074   int frame_complete,
1075   int frame_size,
1076   ByteSize basic_lock_owner_sp_offset,
1077   ByteSize basic_lock_sp_offset,
1078   OopMapSet* oop_maps,
1079   int exception_handler) {
1080   code_buffer->finalize_oop_references(method);
1081   // create nmethod
1082   nmethod* nm = nullptr;
1083   int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1084   {
1085     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1086 
1087     CodeOffsets offsets;
1088     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
1089     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
1090     if (exception_handler != -1) {
1091       offsets.set_value(CodeOffsets::Exceptions, exception_handler);
1092     }
1093 
1094     int mutable_data_size = required_mutable_data_size(code_buffer);
1095 
1096     // MH intrinsics are dispatch stubs which are compatible with NonNMethod space.
1097     // IsUnloadingBehaviour::is_unloading needs to handle them separately.
1098     bool allow_NonNMethod_space = method->can_be_allocated_in_NonNMethod_space();
1099     nm = new (native_nmethod_size, allow_NonNMethod_space)
1100     nmethod(method(), compiler_none, native_nmethod_size,
1101             compile_id, &offsets,
1102             code_buffer, frame_size,
1103             basic_lock_owner_sp_offset,
1104             basic_lock_sp_offset,
1105             oop_maps, mutable_data_size);
1106     DEBUG_ONLY( if (allow_NonNMethod_space) assert_no_oops_or_metadata(nm); )
1107     NOT_PRODUCT(if (nm != nullptr) native_nmethod_stats.note_native_nmethod(nm));
1108   }
1109 
1110   if (nm != nullptr) {
1111     // verify nmethod
1112     DEBUG_ONLY(nm->verify();) // might block
1113 
1114     nm->log_new_nmethod();
1115   }
1116   return nm;
1117 }
1118 
1119 void nmethod::record_nmethod_dependency() {
1120   // To make dependency checking during class loading fast, record
1121   // the nmethod dependencies in the classes it is dependent on.
1122   // This allows the dependency checking code to simply walk the
1123   // class hierarchy above the loaded class, checking only nmethods
1124   // which are dependent on those classes.  The slow way is to
1125   // check every nmethod for dependencies which makes it linear in
1126   // the number of methods compiled.  For applications with a lot
1127   // classes the slow way is too slow.
1128   for (Dependencies::DepStream deps(this); deps.next(); ) {
1129     if (deps.type() == Dependencies::call_site_target_value) {
1130       // CallSite dependencies are managed on per-CallSite instance basis.
1131       oop call_site = deps.argument_oop(0);
1132       MethodHandles::add_dependent_nmethod(call_site, this);
1133     } else {
1134       InstanceKlass* ik = deps.context_type();
1135       if (ik == nullptr) {
1136         continue;  // ignore things like evol_method
1137       }
1138       // record this nmethod as dependent on this klass
1139       ik->add_dependent_nmethod(this);
1140     }
1141   }
1142 }
1143 
1144 nmethod* nmethod::new_nmethod(const methodHandle& method,
1145   int compile_id,
1146   int entry_bci,
1147   CodeOffsets* offsets,
1148   int orig_pc_offset,
1149   DebugInformationRecorder* debug_info,
1150   Dependencies* dependencies,
1151   CodeBuffer* code_buffer, int frame_size,
1152   OopMapSet* oop_maps,
1153   ExceptionHandlerTable* handler_table,
1154   ImplicitExceptionTable* nul_chk_table,
1155   AbstractCompiler* compiler,
1156   CompLevel comp_level
1157 #if INCLUDE_JVMCI
1158   , char* speculations,
1159   int speculations_len,
1160   JVMCINMethodData* jvmci_data
1161 #endif
1162 )
1163 {
1164   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1165   code_buffer->finalize_oop_references(method);
1166   // create nmethod
1167   nmethod* nm = nullptr;
1168   int nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1169 
1170   int immutable_data_size =
1171       adjust_pcs_size(debug_info->pcs_size())
1172     + align_up((int)dependencies->size_in_bytes(), oopSize)
1173     + align_up(handler_table->size_in_bytes()    , oopSize)
1174     + align_up(nul_chk_table->size_in_bytes()    , oopSize)
1175 #if INCLUDE_JVMCI
1176     + align_up(speculations_len                  , oopSize)
1177 #endif
1178     + align_up(debug_info->data_size()           , oopSize)
1179     + align_up(ImmutableDataReferencesCounterSize, oopSize);
1180 
1181   // First, allocate space for immutable data in C heap.
1182   address immutable_data = nullptr;
1183   if (immutable_data_size > 0) {
1184     immutable_data = (address)os::malloc(immutable_data_size, mtCode);
1185     if (immutable_data == nullptr) {
1186       vm_exit_out_of_memory(immutable_data_size, OOM_MALLOC_ERROR, "nmethod: no space for immutable data");
1187       return nullptr;
1188     }
1189   }
1190 
1191   int mutable_data_size = required_mutable_data_size(code_buffer
1192     JVMCI_ONLY(COMMA (compiler->is_jvmci() ? jvmci_data->size() : 0)));
1193 
1194   {
1195     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1196 
1197     nm = new (nmethod_size, comp_level)
1198     nmethod(method(), compiler->type(), nmethod_size, immutable_data_size, mutable_data_size,
1199             compile_id, entry_bci, immutable_data, offsets, orig_pc_offset,
1200             debug_info, dependencies, code_buffer, frame_size, oop_maps,
1201             handler_table, nul_chk_table, compiler, comp_level
1202 #if INCLUDE_JVMCI
1203             , speculations,
1204             speculations_len,
1205             jvmci_data
1206 #endif
1207             );
1208 
1209     if (nm != nullptr) {
1210       nm->record_nmethod_dependency();
1211       NOT_PRODUCT(note_java_nmethod(nm));
1212     }
1213   }
1214   // Do verification and logging outside CodeCache_lock.
1215   if (nm != nullptr) {
1216 
1217 #ifdef ASSERT
1218     LogTarget(Debug, aot, codecache, nmethod) log;
1219     if (log.is_enabled()) {
1220       LogStream out(log);
1221       out.print_cr("== new_nmethod 2");
1222       FlagSetting fs(PrintRelocations, true);
1223       nm->print_on_impl(&out);
1224       nm->decode(&out);
1225     }
1226 #endif
1227 
1228     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
1229     DEBUG_ONLY(nm->verify();)
1230     nm->log_new_nmethod();
1231   }
1232   return nm;
1233 }
1234 
1235 nmethod* nmethod::restore(address code_cache_buffer,
1236                           const methodHandle& method,
1237                           int compile_id,
1238                           address reloc_data,
1239                           GrowableArray<Handle>& oop_list,
1240                           GrowableArray<Metadata*>& metadata_list,
1241                           ImmutableOopMapSet* oop_maps,
1242                           address immutable_data,
1243                           GrowableArray<Handle>& reloc_imm_oop_list,
1244                           GrowableArray<Metadata*>& reloc_imm_metadata_list,
1245                           AOTCodeReader* aot_code_reader)
1246 {
1247   CodeBlob::restore(code_cache_buffer, "nmethod", reloc_data, oop_maps);
1248   nmethod* nm = (nmethod*)code_cache_buffer;
1249   nm->set_method(method());
1250   nm->_compile_id = compile_id;
1251   nm->set_immutable_data(immutable_data);
1252   nm->copy_values(&oop_list);
1253   nm->copy_values(&metadata_list);
1254 
1255   aot_code_reader->fix_relocations(nm, &reloc_imm_oop_list, &reloc_imm_metadata_list);
1256 
1257 #ifndef PRODUCT
1258   nm->asm_remarks().init();
1259   aot_code_reader->read_asm_remarks(nm->asm_remarks(), /* use_string_table */ false);
1260   nm->dbg_strings().init();
1261   aot_code_reader->read_dbg_strings(nm->dbg_strings(), /* use_string_table */ false);
1262 #endif
1263 
1264   // Flush the code block
1265   ICache::invalidate_range(nm->code_begin(), nm->code_size());
1266 
1267   // Create cache after PcDesc data is copied - it will be used to initialize cache
1268   nm->_pc_desc_container = new PcDescContainer(nm->scopes_pcs_begin());
1269 
1270   nm->set_aot_code_entry(aot_code_reader->aot_code_entry());
1271 
1272   nm->post_init();
1273   return nm;
1274 }
1275 
1276 nmethod* nmethod::new_nmethod(nmethod* archived_nm,
1277                               const methodHandle& method,
1278                               AbstractCompiler* compiler,
1279                               int compile_id,
1280                               address reloc_data,
1281                               GrowableArray<Handle>& oop_list,
1282                               GrowableArray<Metadata*>& metadata_list,
1283                               ImmutableOopMapSet* oop_maps,
1284                               address immutable_data,
1285                               GrowableArray<Handle>& reloc_imm_oop_list,
1286                               GrowableArray<Metadata*>& reloc_imm_metadata_list,
1287                               AOTCodeReader* aot_code_reader)
1288 {
1289   nmethod* nm = nullptr;
1290   int nmethod_size = archived_nm->size();
1291   // create nmethod
1292   {
1293     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1294     address code_cache_buffer = (address)CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(archived_nm->comp_level()));
1295     if (code_cache_buffer != nullptr) {
1296       nm = archived_nm->restore(code_cache_buffer,
1297                                 method,
1298                                 compile_id,
1299                                 reloc_data,
1300                                 oop_list,
1301                                 metadata_list,
1302                                 oop_maps,
1303                                 immutable_data,
1304                                 reloc_imm_oop_list,
1305                                 reloc_imm_metadata_list,
1306                                 aot_code_reader);
1307       nm->record_nmethod_dependency();
1308       NOT_PRODUCT(note_java_nmethod(nm));
1309     }
1310   }
1311   // Do verification and logging outside CodeCache_lock.
1312   if (nm != nullptr) {
1313 #ifdef ASSERT
1314     LogTarget(Debug, aot, codecache, nmethod) log;
1315     if (log.is_enabled()) {
1316       LogStream out(log);
1317       out.print_cr("== new_nmethod 2");
1318       FlagSetting fs(PrintRelocations, true);
1319       nm->print_on_impl(&out);
1320       nm->decode(&out);
1321     }
1322 #endif
1323     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
1324     DEBUG_ONLY(nm->verify();)
1325     nm->log_new_nmethod();
1326   }
1327   return nm;
1328 }
1329 
1330 // Fill in default values for various fields
1331 void nmethod::init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets) {
1332   // avoid uninitialized fields, even for short time periods
1333   _exception_cache            = nullptr;
1334   _gc_data                    = nullptr;
1335   _oops_do_mark_link          = nullptr;
1336   _compiled_ic_data           = nullptr;
1337 
1338   _is_unloading_state         = 0;
1339   _state                      = not_installed;
1340 
1341   _has_unsafe_access          = 0;
1342   _has_wide_vectors           = 0;
1343   _has_monitors               = 0;
1344   _has_scoped_access          = 0;
1345   _has_flushed_dependencies   = 0;
1346   _is_unlinked                = 0;
1347   _load_reported              = 0; // jvmti state
1348   _preloaded                  = 0;
1349   _has_clinit_barriers        = 0;
1350 
1351   _used                       = false;
1352   _deoptimization_status      = not_marked;
1353 
1354   // SECT_CONSTS is first in code buffer so the offset should be 0.
1355   int consts_offset = code_buffer->total_offset_of(code_buffer->consts());
1356   assert(consts_offset == 0, "const_offset: %d", consts_offset);
1357 
1358   _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
1359 
1360   CHECKED_CAST(_entry_offset,              uint16_t, (offsets->value(CodeOffsets::Entry)));
1361   CHECKED_CAST(_verified_entry_offset,     uint16_t, (offsets->value(CodeOffsets::Verified_Entry)));
1362 
1363   _skipped_instructions_size = code_buffer->total_skipped_instructions_size();
1364 }
1365 
1366 // Post initialization
1367 void nmethod::post_init() {
1368   clear_unloading_state();
1369 
1370   finalize_relocations();
1371 
1372   Universe::heap()->register_nmethod(this);
1373   DEBUG_ONLY(Universe::heap()->verify_nmethod(this));
1374 
1375   CodeCache::commit(this);
1376 }
1377 
1378 // For native wrappers
1379 nmethod::nmethod(
1380   Method* method,
1381   CompilerType type,
1382   int nmethod_size,
1383   int compile_id,
1384   CodeOffsets* offsets,
1385   CodeBuffer* code_buffer,
1386   int frame_size,
1387   ByteSize basic_lock_owner_sp_offset,
1388   ByteSize basic_lock_sp_offset,
1389   OopMapSet* oop_maps,
1390   int mutable_data_size)
1391   : CodeBlob("native nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1392              offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, mutable_data_size),
1393   _deoptimization_generation(0),
1394   _gc_epoch(CodeCache::gc_epoch()),
1395   _method(method),
1396   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
1397   _native_basic_lock_sp_offset(basic_lock_sp_offset)
1398 {
1399   {
1400     DEBUG_ONLY(NoSafepointVerifier nsv;)
1401     assert_locked_or_safepoint(CodeCache_lock);
1402 
1403     init_defaults(code_buffer, offsets);
1404 
1405     _osr_entry_point         = nullptr;
1406     _pc_desc_container       = nullptr;
1407     _entry_bci               = InvocationEntryBci;
1408     _compile_id              = compile_id;
1409     _comp_level              = CompLevel_none;
1410     _compiler_type           = type;
1411     _orig_pc_offset          = 0;
1412     _num_stack_arg_slots     = 0;
1413 
1414     if (offsets->value(CodeOffsets::Exceptions) != -1) {
1415       // Continuation enter intrinsic
1416       _exception_offset      = code_offset() + offsets->value(CodeOffsets::Exceptions);
1417     } else {
1418       _exception_offset      = 0;
1419     }
1420     // Native wrappers do not have deopt handlers. Make the values
1421     // something that will never match a pc like the nmethod vtable entry
1422     _deopt_handler_offset    = 0;
1423     _aot_code_entry          = nullptr;
1424     _method_profiling_count  = 0;
1425     _unwind_handler_offset   = 0;
1426 
1427     CHECKED_CAST(_oops_size, uint16_t, align_up(code_buffer->total_oop_size(), oopSize));
1428     uint16_t metadata_size;
1429     CHECKED_CAST(metadata_size, uint16_t, align_up(code_buffer->total_metadata_size(), wordSize));
1430     JVMCI_ONLY( _metadata_size = metadata_size; )
1431     assert(_mutable_data_size == _relocation_size + metadata_size,
1432            "wrong mutable data size: %d != %d + %d",
1433            _mutable_data_size, _relocation_size, metadata_size);
1434 
1435     // native wrapper does not have read-only data but we need unique not null address
1436     _immutable_data          = blob_end();
1437     _immutable_data_size     = 0;
1438     _nul_chk_table_offset    = 0;
1439     _handler_table_offset    = 0;
1440     _scopes_pcs_offset       = 0;
1441     _scopes_data_offset      = 0;
1442 #if INCLUDE_JVMCI
1443     _speculations_offset     = 0;
1444 #endif
1445 
1446     code_buffer->copy_code_and_locs_to(this);
1447     code_buffer->copy_values_to(this);
1448 
1449     post_init();
1450   }
1451 
1452   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
1453     ttyLocker ttyl;  // keep the following output all in one block
1454     // This output goes directly to the tty, not the compiler log.
1455     // To enable tools to match it up with the compilation activity,
1456     // be sure to tag this tty output with the compile ID.
1457     if (xtty != nullptr) {
1458       xtty->begin_head("print_native_nmethod");
1459       xtty->method(_method);
1460       xtty->stamp();
1461       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
1462     }
1463     // Print the header part, then print the requested information.
1464     // This is both handled in decode2(), called via print_code() -> decode()
1465     if (PrintNativeNMethods) {
1466       tty->print_cr("-------------------------- Assembly (native nmethod) ---------------------------");
1467       print_code();
1468       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1469 #if defined(SUPPORT_DATA_STRUCTS)
1470       if (AbstractDisassembler::show_structs()) {
1471         if (oop_maps != nullptr) {
1472           tty->print("oop maps:"); // oop_maps->print_on(tty) outputs a cr() at the beginning
1473           oop_maps->print_on(tty);
1474           tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1475         }
1476       }
1477 #endif
1478     } else {
1479       print(); // print the header part only.
1480     }
1481 #if defined(SUPPORT_DATA_STRUCTS)
1482     if (AbstractDisassembler::show_structs()) {
1483       if (PrintRelocations) {
1484         print_relocations_on(tty);
1485         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1486       }
1487     }
1488 #endif
1489     if (xtty != nullptr) {
1490       xtty->tail("print_native_nmethod");
1491     }
1492   }
1493 }
1494 
1495 
1496 nmethod::nmethod(const nmethod &nm) : CodeBlob(nm._name, nm._kind, nm._size, nm._header_size)
1497 {
1498 
1499   if (nm._oop_maps != nullptr) {
1500     _oop_maps                   = nm._oop_maps->clone();
1501   } else {
1502     _oop_maps                   = nullptr;
1503   }
1504 
1505   _size                         = nm._size;
1506   _relocation_size              = nm._relocation_size;
1507   _content_offset               = nm._content_offset;
1508   _code_offset                  = nm._code_offset;
1509   _data_offset                  = nm._data_offset;
1510   _frame_size                   = nm._frame_size;
1511 
1512   S390_ONLY( _ctable_offset     = nm._ctable_offset; )
1513 
1514   _header_size                  = nm._header_size;
1515   _frame_complete_offset        = nm._frame_complete_offset;
1516 
1517   _kind                         = nm._kind;
1518 
1519   _caller_must_gc_arguments     = nm._caller_must_gc_arguments;
1520 
1521 #ifndef PRODUCT
1522   _asm_remarks.share(nm._asm_remarks);
1523   _dbg_strings.share(nm._dbg_strings);
1524 #endif
1525 
1526   // Allocate memory and copy mutable data to C heap
1527   _mutable_data_size            = nm._mutable_data_size;
1528   if (_mutable_data_size > 0) {
1529     _mutable_data = (address)os::malloc(_mutable_data_size, mtCode);
1530     if (_mutable_data == nullptr) {
1531       vm_exit_out_of_memory(_mutable_data_size, OOM_MALLOC_ERROR, "nmethod: no space for mutable data");
1532     }
1533     memcpy(mutable_data_begin(), nm.mutable_data_begin(), nm.mutable_data_size());
1534   } else {
1535     _mutable_data               = nullptr;
1536   }
1537 
1538   _deoptimization_generation    = 0;
1539   _gc_epoch                     = CodeCache::gc_epoch();
1540   _method                       = nm._method;
1541   _osr_link                     = nullptr;
1542 
1543   // Increment number of references to immutable data to share it between nmethods
1544   _immutable_data_size          = nm._immutable_data_size;
1545   if (_immutable_data_size > 0) {
1546     _immutable_data             = nm._immutable_data;
1547     set_immutable_data_references_counter(get_immutable_data_references_counter() + 1);
1548   } else {
1549     _immutable_data             = blob_end();
1550   }
1551 
1552   _exception_cache              = nullptr;
1553   _gc_data                      = nullptr;
1554   _oops_do_mark_nmethods        = nullptr;
1555   _oops_do_mark_link            = nullptr;
1556   _compiled_ic_data             = nullptr;
1557 
1558   if (nm._osr_entry_point != nullptr) {
1559     _osr_entry_point            = (nm._osr_entry_point - (address) &nm) + (address) this;
1560   } else {
1561     _osr_entry_point            = nullptr;
1562   }
1563 
1564   _entry_offset                 = nm._entry_offset;
1565   _verified_entry_offset        = nm._verified_entry_offset;
1566   _entry_bci                    = nm._entry_bci;
1567 
1568   _skipped_instructions_size    = nm._skipped_instructions_size;
1569   _stub_offset                  = nm._stub_offset;
1570   _exception_offset             = nm._exception_offset;
1571   _deopt_handler_offset         = nm._deopt_handler_offset;
1572   _unwind_handler_offset        = nm._unwind_handler_offset;
1573   _num_stack_arg_slots          = nm._num_stack_arg_slots;
1574   _oops_size                    = nm._oops_size;
1575 #if INCLUDE_JVMCI
1576   _metadata_size                = nm._metadata_size;
1577 #endif
1578   _nul_chk_table_offset         = nm._nul_chk_table_offset;
1579   _handler_table_offset         = nm._handler_table_offset;
1580   _scopes_pcs_offset            = nm._scopes_pcs_offset;
1581   _scopes_data_offset           = nm._scopes_data_offset;
1582 #if INCLUDE_JVMCI
1583   _speculations_offset          = nm._speculations_offset;
1584 #endif
1585 
1586   _orig_pc_offset               = nm._orig_pc_offset;
1587   _compile_id                   = nm._compile_id;
1588   _comp_level                   = nm._comp_level;
1589   _compiler_type                = nm._compiler_type;
1590   _is_unloading_state           = nm._is_unloading_state;
1591   _state                        = not_installed;
1592 
1593   _has_unsafe_access            = nm._has_unsafe_access;
1594   _has_wide_vectors             = nm._has_wide_vectors;
1595   _has_monitors                 = nm._has_monitors;
1596   _has_scoped_access            = nm._has_scoped_access;
1597   _has_flushed_dependencies     = nm._has_flushed_dependencies;
1598   _is_unlinked                  = nm._is_unlinked;
1599   _load_reported                = nm._load_reported;
1600 
1601   _deoptimization_status        = nm._deoptimization_status;
1602 
1603   if (nm._pc_desc_container != nullptr) {
1604     _pc_desc_container          = new PcDescContainer(scopes_pcs_begin());
1605   } else {
1606     _pc_desc_container          = nullptr;
1607   }
1608 
1609   // Copy nmethod contents excluding header
1610   // - Constant part          (doubles, longs and floats used in nmethod)
1611   // - Code part:
1612   //   - Code body
1613   //   - Exception handler
1614   //   - Stub code
1615   //   - OOP table
1616   memcpy(consts_begin(), nm.consts_begin(), nm.data_end() - nm.consts_begin());
1617 
1618   post_init();
1619 }
1620 
1621 nmethod* nmethod::relocate(CodeBlobType code_blob_type) {
1622   assert(NMethodRelocation, "must enable use of function");
1623 
1624   // Locks required to be held by caller to ensure the nmethod
1625   // is not modified or purged from code cache during relocation
1626   assert_lock_strong(CodeCache_lock);
1627   assert_lock_strong(Compile_lock);
1628   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1629 
1630   if (!is_relocatable()) {
1631     return nullptr;
1632   }
1633 
1634   run_nmethod_entry_barrier();
1635   nmethod* nm_copy = new (size(), code_blob_type) nmethod(*this);
1636 
1637   if (nm_copy == nullptr) {
1638     return nullptr;
1639   }
1640 
1641   // Fix relocation
1642   RelocIterator iter(nm_copy);
1643   CodeBuffer src(this);
1644   CodeBuffer dst(nm_copy);
1645   while (iter.next()) {
1646 #ifdef USE_TRAMPOLINE_STUB_FIX_OWNER
1647     // Direct calls may no longer be in range and the use of a trampoline may now be required.
1648     // Instead, allow trampoline relocations to update their owners and perform the necessary checks.
1649     if (iter.reloc()->is_call()) {
1650       address trampoline = trampoline_stub_Relocation::get_trampoline_for(iter.reloc()->addr(), nm_copy);
1651       if (trampoline != nullptr) {
1652         continue;
1653       }
1654     }
1655 #endif
1656 
1657     iter.reloc()->fix_relocation_after_move(&src, &dst);
1658   }
1659 
1660   // To make dependency checking during class loading fast, record
1661   // the nmethod dependencies in the classes it is dependent on.
1662   // This allows the dependency checking code to simply walk the
1663   // class hierarchy above the loaded class, checking only nmethods
1664   // which are dependent on those classes.  The slow way is to
1665   // check every nmethod for dependencies which makes it linear in
1666   // the number of methods compiled.  For applications with a lot
1667   // classes the slow way is too slow.
1668   for (Dependencies::DepStream deps(nm_copy); deps.next(); ) {
1669     if (deps.type() == Dependencies::call_site_target_value) {
1670       // CallSite dependencies are managed on per-CallSite instance basis.
1671       oop call_site = deps.argument_oop(0);
1672       MethodHandles::add_dependent_nmethod(call_site, nm_copy);
1673     } else {
1674       InstanceKlass* ik = deps.context_type();
1675       if (ik == nullptr) {
1676         continue;  // ignore things like evol_method
1677       }
1678       // record this nmethod as dependent on this klass
1679       ik->add_dependent_nmethod(nm_copy);
1680     }
1681   }
1682 
1683   MutexLocker ml_NMethodState_lock(NMethodState_lock, Mutex::_no_safepoint_check_flag);
1684 
1685   // Verify the nm we copied from is still valid
1686   if (!is_marked_for_deoptimization() && is_in_use()) {
1687     assert(method() != nullptr && method()->code() == this, "should be if is in use");
1688 
1689     nm_copy->clear_inline_caches();
1690 
1691     // Attempt to start using the copy
1692     if (nm_copy->make_in_use()) {
1693       ICache::invalidate_range(nm_copy->code_begin(), nm_copy->code_size());
1694 
1695       methodHandle mh(Thread::current(), nm_copy->method());
1696       nm_copy->method()->set_code(mh, nm_copy);
1697 
1698       make_not_used();
1699 
1700       nm_copy->post_compiled_method_load_event();
1701 
1702       nm_copy->log_relocated_nmethod(this);
1703 
1704       return nm_copy;
1705     }
1706   }
1707 
1708   nm_copy->make_not_used();
1709 
1710   return nullptr;
1711 }
1712 
1713 bool nmethod::is_relocatable() {
1714   if (!is_java_method()) {
1715     return false;
1716   }
1717 
1718   if (!is_in_use()) {
1719     return false;
1720   }
1721 
1722   if (is_osr_method()) {
1723     return false;
1724   }
1725 
1726   if (is_marked_for_deoptimization()) {
1727     return false;
1728   }
1729 
1730 #if INCLUDE_JVMCI
1731   if (jvmci_nmethod_data() != nullptr && jvmci_nmethod_data()->has_mirror()) {
1732     return false;
1733   }
1734 #endif
1735 
1736   if (is_unloading()) {
1737     return false;
1738   }
1739 
1740   if (has_evol_metadata()) {
1741     return false;
1742   }
1743 
1744   return true;
1745 }
1746 
1747 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
1748   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
1749 }
1750 
1751 void* nmethod::operator new(size_t size, int nmethod_size, CodeBlobType code_blob_type) throw () {
1752   return CodeCache::allocate(nmethod_size, code_blob_type);
1753 }
1754 
1755 void* nmethod::operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw () {
1756   // Try MethodNonProfiled and MethodProfiled.
1757   void* return_value = CodeCache::allocate(nmethod_size, CodeBlobType::MethodNonProfiled);
1758   if (return_value != nullptr || !allow_NonNMethod_space) return return_value;
1759   // Try NonNMethod or give up.
1760   return CodeCache::allocate(nmethod_size, CodeBlobType::NonNMethod);
1761 }
1762 
1763 // For normal JIT compiled code
1764 nmethod::nmethod(
1765   Method* method,
1766   CompilerType type,
1767   int nmethod_size,
1768   int immutable_data_size,
1769   int mutable_data_size,
1770   int compile_id,
1771   int entry_bci,
1772   address immutable_data,
1773   CodeOffsets* offsets,
1774   int orig_pc_offset,
1775   DebugInformationRecorder* debug_info,
1776   Dependencies* dependencies,
1777   CodeBuffer *code_buffer,
1778   int frame_size,
1779   OopMapSet* oop_maps,
1780   ExceptionHandlerTable* handler_table,
1781   ImplicitExceptionTable* nul_chk_table,
1782   AbstractCompiler* compiler,
1783   CompLevel comp_level
1784 #if INCLUDE_JVMCI
1785   , char* speculations,
1786   int speculations_len,
1787   JVMCINMethodData* jvmci_data
1788 #endif
1789   )
1790   : CodeBlob("nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1791              offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, mutable_data_size),
1792   _deoptimization_generation(0),
1793   _gc_epoch(CodeCache::gc_epoch()),
1794   _method(method),
1795   _osr_link(nullptr)
1796 {
1797   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1798   {
1799     DEBUG_ONLY(NoSafepointVerifier nsv;)
1800     assert_locked_or_safepoint(CodeCache_lock);
1801 
1802     init_defaults(code_buffer, offsets);
1803     _aot_code_entry          = nullptr; // runtime compiled nmethod does not have AOTCodeEntry
1804     _method_profiling_count  = 0;
1805 
1806     _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
1807     _entry_bci       = entry_bci;
1808     _compile_id      = compile_id;
1809     _comp_level      = comp_level;
1810     _compiler_type   = type;
1811     _orig_pc_offset  = orig_pc_offset;
1812 
1813     _num_stack_arg_slots = entry_bci != InvocationEntryBci ? 0 : _method->constMethod()->num_stack_arg_slots();
1814 
1815     set_ctable_begin(header_begin() + content_offset());
1816 
1817 #if INCLUDE_JVMCI
1818     if (compiler->is_jvmci()) {
1819       // JVMCI might not produce any stub sections
1820       if (offsets->value(CodeOffsets::Exceptions) != -1) {
1821         _exception_offset        = code_offset() + offsets->value(CodeOffsets::Exceptions);
1822       } else {
1823         _exception_offset        = -1;
1824       }
1825       if (offsets->value(CodeOffsets::Deopt) != -1) {
1826         _deopt_handler_offset    = code_offset() + offsets->value(CodeOffsets::Deopt);
1827       } else {
1828         _deopt_handler_offset    = -1;
1829       }
1830     } else
1831 #endif
1832     {
1833       // Exception handler and deopt handler are in the stub section
1834       assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
1835       assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
1836 
1837       _exception_offset          = _stub_offset + offsets->value(CodeOffsets::Exceptions);
1838       _deopt_handler_offset      = _stub_offset + offsets->value(CodeOffsets::Deopt);
1839     }
1840     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
1841       // C1 generates UnwindHandler at the end of instructions section.
1842       // Calculate positive offset as distance between the start of stubs section
1843       // (which is also the end of instructions section) and the start of the handler.
1844       int unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
1845       CHECKED_CAST(_unwind_handler_offset, int16_t, (_stub_offset - unwind_handler_offset));
1846     } else {
1847       _unwind_handler_offset = -1;
1848     }
1849 
1850     CHECKED_CAST(_oops_size, uint16_t, align_up(code_buffer->total_oop_size(), oopSize));
1851     uint16_t metadata_size;
1852     CHECKED_CAST(metadata_size, uint16_t, align_up(code_buffer->total_metadata_size(), wordSize));
1853     JVMCI_ONLY( _metadata_size = metadata_size; )
1854     int jvmci_data_size = 0 JVMCI_ONLY( + align_up(compiler->is_jvmci() ? jvmci_data->size() : 0, oopSize));
1855     assert(_mutable_data_size == _relocation_size + metadata_size + jvmci_data_size,
1856            "wrong mutable data size: %d != %d + %d + %d",
1857            _mutable_data_size, _relocation_size, metadata_size, jvmci_data_size);
1858     assert(nmethod_size == data_end() - header_begin(), "wrong nmethod size: %d != %d",
1859            nmethod_size, (int)(code_end() - header_begin()));
1860 
1861     _immutable_data_size  = immutable_data_size;
1862     if (immutable_data_size > 0) {
1863       assert(immutable_data != nullptr, "required");
1864       _immutable_data     = immutable_data;
1865     } else {
1866       // We need unique not null address
1867       _immutable_data     = blob_end();
1868     }
1869     CHECKED_CAST(_nul_chk_table_offset, uint16_t, (align_up((int)dependencies->size_in_bytes(), oopSize)));
1870     CHECKED_CAST(_handler_table_offset, uint16_t, (_nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize)));
1871     _scopes_pcs_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
1872     _scopes_data_offset   = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
1873 
1874 #if INCLUDE_JVMCI
1875     _speculations_offset  = _scopes_data_offset   + align_up(debug_info->data_size(), oopSize);
1876     DEBUG_ONLY( int immutable_data_end_offset = _speculations_offset + align_up(speculations_len, oopSize) + align_up(ImmutableDataReferencesCounterSize, oopSize); )
1877 #else
1878     DEBUG_ONLY( int immutable_data_end_offset = _scopes_data_offset + align_up(debug_info->data_size(), oopSize) + align_up(ImmutableDataReferencesCounterSize, oopSize); )
1879 #endif
1880     assert(immutable_data_end_offset <= immutable_data_size, "wrong read-only data size: %d > %d",
1881            immutable_data_end_offset, immutable_data_size);
1882 
1883     // Copy code and relocation info
1884     code_buffer->copy_code_and_locs_to(this);
1885     // Copy oops and metadata
1886     code_buffer->copy_values_to(this);
1887     dependencies->copy_to(this);
1888     // Copy PcDesc and ScopeDesc data
1889     debug_info->copy_to(this);
1890 
1891     // Create cache after PcDesc data is copied - it will be used to initialize cache
1892     _pc_desc_container = new PcDescContainer(scopes_pcs_begin());
1893 
1894 #if INCLUDE_JVMCI
1895     if (compiler->is_jvmci()) {
1896       // Initialize the JVMCINMethodData object inlined into nm
1897       jvmci_nmethod_data()->copy(jvmci_data);
1898     }
1899 #endif
1900 
1901     // Copy contents of ExceptionHandlerTable to nmethod
1902     handler_table->copy_to(this);
1903     nul_chk_table->copy_to(this);
1904 
1905 #if INCLUDE_JVMCI
1906     // Copy speculations to nmethod
1907     if (speculations_size() != 0) {
1908       memcpy(speculations_begin(), speculations, speculations_len);
1909     }
1910 #endif
1911     set_immutable_data_references_counter(1);
1912 
1913     post_init();
1914 
1915     // we use the information of entry points to find out if a method is
1916     // static or non static
1917     assert(compiler->is_c2() || compiler->is_jvmci() ||
1918            _method->is_static() == (entry_point() == verified_entry_point()),
1919            " entry points must be same for static methods and vice versa");
1920   }
1921 }
1922 
1923 // Print a short set of xml attributes to identify this nmethod.  The
1924 // output should be embedded in some other element.
1925 void nmethod::log_identity(xmlStream* log) const {
1926   assert(log->inside_attrs_or_error(), "printing attributes");
1927   log->print(" compile_id='%d'", compile_id());
1928   const char* nm_kind = compile_kind();
1929   if (nm_kind != nullptr)  log->print(" compile_kind='%s'", nm_kind);
1930   log->print(" compiler='%s'", compiler_name());
1931   if (TieredCompilation) {
1932     log->print(" compile_level='%d'", comp_level());
1933   }
1934 #if INCLUDE_JVMCI
1935   if (jvmci_nmethod_data() != nullptr) {
1936     const char* jvmci_name = jvmci_nmethod_data()->name();
1937     if (jvmci_name != nullptr) {
1938       log->print(" jvmci_mirror_name='");
1939       log->text("%s", jvmci_name);
1940       log->print("'");
1941     }
1942   }
1943 #endif
1944 }
1945 
1946 
1947 #define LOG_OFFSET(log, name)                    \
1948   if (p2i(name##_end()) - p2i(name##_begin())) \
1949     log->print(" " XSTR(name) "_offset='%zd'"    , \
1950                p2i(name##_begin()) - p2i(this))
1951 
1952 
1953 void nmethod::log_new_nmethod() const {
1954   if (LogCompilation && xtty != nullptr) {
1955     ttyLocker ttyl;
1956     xtty->begin_elem("nmethod");
1957     log_identity(xtty);
1958     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
1959     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
1960 
1961     LOG_OFFSET(xtty, relocation);
1962     LOG_OFFSET(xtty, consts);
1963     LOG_OFFSET(xtty, insts);
1964     LOG_OFFSET(xtty, stub);
1965     LOG_OFFSET(xtty, scopes_data);
1966     LOG_OFFSET(xtty, scopes_pcs);
1967     LOG_OFFSET(xtty, dependencies);
1968     LOG_OFFSET(xtty, handler_table);
1969     LOG_OFFSET(xtty, nul_chk_table);
1970     LOG_OFFSET(xtty, oops);
1971     LOG_OFFSET(xtty, metadata);
1972 
1973     xtty->method(method());
1974     xtty->stamp();
1975     xtty->end_elem();
1976   }
1977 }
1978 
1979 
1980 void nmethod::log_relocated_nmethod(nmethod* original) const {
1981   if (LogCompilation && xtty != nullptr) {
1982     ttyLocker ttyl;
1983     xtty->begin_elem("relocated nmethod");
1984     log_identity(xtty);
1985     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
1986 
1987     const char* original_code_heap_name = CodeCache::get_code_heap_name(CodeCache::get_code_blob_type(original));
1988     xtty->print(" original_address='" INTPTR_FORMAT "'", p2i(original));
1989     xtty->print(" original_code_heap='%s'", original_code_heap_name);
1990 
1991     const char* new_code_heap_name = CodeCache::get_code_heap_name(CodeCache::get_code_blob_type(this));
1992     xtty->print(" new_address='" INTPTR_FORMAT "'", p2i(this));
1993     xtty->print(" new_code_heap='%s'", new_code_heap_name);
1994 
1995     LOG_OFFSET(xtty, relocation);
1996     LOG_OFFSET(xtty, consts);
1997     LOG_OFFSET(xtty, insts);
1998     LOG_OFFSET(xtty, stub);
1999     LOG_OFFSET(xtty, scopes_data);
2000     LOG_OFFSET(xtty, scopes_pcs);
2001     LOG_OFFSET(xtty, dependencies);
2002     LOG_OFFSET(xtty, handler_table);
2003     LOG_OFFSET(xtty, nul_chk_table);
2004     LOG_OFFSET(xtty, oops);
2005     LOG_OFFSET(xtty, metadata);
2006 
2007     xtty->method(method());
2008     xtty->stamp();
2009     xtty->end_elem();
2010   }
2011 }
2012 
2013 #undef LOG_OFFSET
2014 
2015 
2016 // Print out more verbose output usually for a newly created nmethod.
2017 void nmethod::print_on_with_msg(outputStream* st, const char* msg) const {
2018   if (st != nullptr) {
2019     ttyLocker ttyl;
2020     if (WizardMode) {
2021       CompileTask::print(st, this, msg, /*short_form:*/ true);
2022       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
2023     } else {
2024       CompileTask::print(st, this, msg, /*short_form:*/ false);
2025     }
2026   }
2027 }
2028 
2029 void nmethod::maybe_print_nmethod(const DirectiveSet* directive) {
2030   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
2031   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
2032     print_nmethod(printnmethods);
2033   }
2034 }
2035 
2036 void nmethod::print_nmethod(bool printmethod) {
2037   ttyLocker ttyl;  // keep the following output all in one block
2038   if (xtty != nullptr) {
2039     xtty->begin_head("print_nmethod");
2040     log_identity(xtty);
2041     xtty->stamp();
2042     xtty->end_head();
2043   }
2044   // Print the header part, then print the requested information.
2045   // This is both handled in decode2().
2046   if (printmethod) {
2047     ResourceMark m;
2048     if (is_compiled_by_c1()) {
2049       tty->cr();
2050       tty->print_cr("============================= C1-compiled nmethod ==============================");
2051     }
2052     if (is_compiled_by_jvmci()) {
2053       tty->cr();
2054       tty->print_cr("=========================== JVMCI-compiled nmethod =============================");
2055     }
2056     tty->print_cr("----------------------------------- Assembly -----------------------------------");
2057     decode2(tty);
2058 #if defined(SUPPORT_DATA_STRUCTS)
2059     if (AbstractDisassembler::show_structs()) {
2060       // Print the oops from the underlying CodeBlob as well.
2061       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2062       print_oops(tty);
2063       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2064       print_metadata(tty);
2065       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2066       print_pcs_on(tty);
2067       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2068       if (oop_maps() != nullptr) {
2069         tty->print("oop maps:"); // oop_maps()->print_on(tty) outputs a cr() at the beginning
2070         oop_maps()->print_on(tty);
2071         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2072       }
2073     }
2074 #endif
2075   } else {
2076     print(); // print the header part only.
2077   }
2078 
2079 #if defined(SUPPORT_DATA_STRUCTS)
2080   if (AbstractDisassembler::show_structs()) {
2081     methodHandle mh(Thread::current(), _method);
2082     if (printmethod || PrintDebugInfo || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDebugInfo)) {
2083       print_scopes();
2084       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2085     }
2086     if (printmethod || PrintRelocations || CompilerOracle::has_option(mh, CompileCommandEnum::PrintRelocations)) {
2087       print_relocations_on(tty);
2088       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2089     }
2090     if (printmethod || PrintDependencies || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDependencies)) {
2091       print_dependencies_on(tty);
2092       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2093     }
2094     if (printmethod || PrintExceptionHandlers) {
2095       print_handler_table();
2096       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2097       print_nul_chk_table();
2098       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2099     }
2100 
2101     if (printmethod) {
2102       print_recorded_oops();
2103       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2104       print_recorded_metadata();
2105       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
2106     }
2107   }
2108 #endif
2109 
2110   if (xtty != nullptr) {
2111     xtty->tail("print_nmethod");
2112   }
2113 }
2114 
2115 
2116 // Promote one word from an assembly-time handle to a live embedded oop.
2117 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
2118   if (handle == nullptr ||
2119       // As a special case, IC oops are initialized to 1 or -1.
2120       handle == (jobject) Universe::non_oop_word()) {
2121     *(void**)dest = handle;
2122   } else {
2123     *dest = JNIHandles::resolve_non_null(handle);
2124   }
2125 }
2126 
2127 void nmethod::copy_values(GrowableArray<Handle>* array) {
2128   int length = array->length();
2129   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
2130   oop* dest = oops_begin();
2131   for (int index = 0 ; index < length; index++) {
2132     dest[index] = array->at(index)();
2133   }
2134 }
2135 
2136 // Have to have the same name because it's called by a template
2137 void nmethod::copy_values(GrowableArray<jobject>* array) {
2138   int length = array->length();
2139   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
2140   oop* dest = oops_begin();
2141   for (int index = 0 ; index < length; index++) {
2142     initialize_immediate_oop(&dest[index], array->at(index));
2143   }
2144 
2145   // Now we can fix up all the oops in the code.  We need to do this
2146   // in the code because the assembler uses jobjects as placeholders.
2147   // The code and relocations have already been initialized by the
2148   // CodeBlob constructor, so it is valid even at this early point to
2149   // iterate over relocations and patch the code.
2150   fix_oop_relocations(nullptr, nullptr, /*initialize_immediates=*/ true);
2151 }
2152 
2153 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
2154   int length = array->length();
2155   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
2156   Metadata** dest = metadata_begin();
2157   for (int index = 0 ; index < length; index++) {
2158     dest[index] = array->at(index);
2159   }
2160 }
2161 
2162 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
2163   // re-patch all oop-bearing instructions, just in case some oops moved
2164   RelocIterator iter(this, begin, end);
2165   while (iter.next()) {
2166     if (iter.type() == relocInfo::oop_type) {
2167       oop_Relocation* reloc = iter.oop_reloc();
2168       if (initialize_immediates && reloc->oop_is_immediate()) {
2169         oop* dest = reloc->oop_addr();
2170         jobject obj = *reinterpret_cast<jobject*>(dest);
2171         initialize_immediate_oop(dest, obj);
2172       }
2173       // Refresh the oop-related bits of this instruction.
2174       reloc->fix_oop_relocation();
2175     } else if (iter.type() == relocInfo::metadata_type) {
2176       metadata_Relocation* reloc = iter.metadata_reloc();
2177       reloc->fix_metadata_relocation();
2178     }
2179   }
2180 }
2181 
2182 void nmethod::create_reloc_immediates_list(JavaThread* thread, GrowableArray<Handle>& oop_list, GrowableArray<Metadata*>& metadata_list) {
2183   RelocIterator iter(this);
2184   while (iter.next()) {
2185     if (iter.type() == relocInfo::oop_type) {
2186       oop_Relocation* reloc = iter.oop_reloc();
2187       if (reloc->oop_is_immediate()) {
2188         oop dest = reloc->oop_value();
2189         Handle h(thread, dest);
2190         oop_list.append(h);
2191       }
2192     } else if (iter.type() == relocInfo::metadata_type) {
2193       metadata_Relocation* reloc = iter.metadata_reloc();
2194       if (reloc->metadata_is_immediate()) {
2195         Metadata* m = reloc->metadata_value();
2196         metadata_list.append(m);
2197       }
2198     }
2199   }
2200 }
2201 
2202 static void install_post_call_nop_displacement(nmethod* nm, address pc) {
2203   NativePostCallNop* nop = nativePostCallNop_at((address) pc);
2204   intptr_t cbaddr = (intptr_t) nm;
2205   intptr_t offset = ((intptr_t) pc) - cbaddr;
2206 
2207   int oopmap_slot = nm->oop_maps()->find_slot_for_offset(int((intptr_t) pc - (intptr_t) nm->code_begin()));
2208   if (oopmap_slot < 0) { // this can happen at asynchronous (non-safepoint) stackwalks
2209     log_debug(codecache)("failed to find oopmap for cb: " INTPTR_FORMAT " offset: %d", cbaddr, (int) offset);
2210   } else if (!nop->patch(oopmap_slot, offset)) {
2211     log_debug(codecache)("failed to encode %d %d", oopmap_slot, (int) offset);
2212   }
2213 }
2214 
2215 void nmethod::finalize_relocations() {
2216   NoSafepointVerifier nsv;
2217 
2218   GrowableArray<NativeMovConstReg*> virtual_call_data;
2219 
2220   // Make sure that post call nops fill in nmethod offsets eagerly so
2221   // we don't have to race with deoptimization
2222   RelocIterator iter(this);
2223   while (iter.next()) {
2224     if (iter.type() == relocInfo::virtual_call_type) {
2225       virtual_call_Relocation* r = iter.virtual_call_reloc();
2226       NativeMovConstReg* value = nativeMovConstReg_at(r->cached_value());
2227       virtual_call_data.append(value);
2228     } else if (iter.type() == relocInfo::post_call_nop_type) {
2229       post_call_nop_Relocation* const reloc = iter.post_call_nop_reloc();
2230       address pc = reloc->addr();
2231       install_post_call_nop_displacement(this, pc);
2232     }
2233   }
2234 
2235   if (virtual_call_data.length() > 0) {
2236     // We allocate a block of CompiledICData per nmethod so the GC can purge this faster.
2237     _compiled_ic_data = new CompiledICData[virtual_call_data.length()];
2238     CompiledICData* next_data = _compiled_ic_data;
2239 
2240     for (NativeMovConstReg* value : virtual_call_data) {
2241       value->set_data((intptr_t)next_data);
2242       next_data++;
2243     }
2244   }
2245 }
2246 
2247 void nmethod::make_deoptimized() {
2248   if (!Continuations::enabled()) {
2249     // Don't deopt this again.
2250     set_deoptimized_done();
2251     return;
2252   }
2253 
2254   assert(method() == nullptr || can_be_deoptimized(), "");
2255 
2256   CompiledICLocker ml(this);
2257   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
2258 
2259   // If post call nops have been already patched, we can just bail-out.
2260   if (has_been_deoptimized()) {
2261     return;
2262   }
2263 
2264   ResourceMark rm;
2265   RelocIterator iter(this, oops_reloc_begin());
2266 
2267   while (iter.next()) {
2268 
2269     switch (iter.type()) {
2270       case relocInfo::virtual_call_type: {
2271         CompiledIC *ic = CompiledIC_at(&iter);
2272         address pc = ic->end_of_call();
2273         NativePostCallNop* nop = nativePostCallNop_at(pc);
2274         if (nop != nullptr) {
2275           nop->make_deopt();
2276         }
2277         assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
2278         break;
2279       }
2280       case relocInfo::static_call_type:
2281       case relocInfo::opt_virtual_call_type: {
2282         CompiledDirectCall *csc = CompiledDirectCall::at(iter.reloc());
2283         address pc = csc->end_of_call();
2284         NativePostCallNop* nop = nativePostCallNop_at(pc);
2285         //tty->print_cr(" - static pc %p", pc);
2286         if (nop != nullptr) {
2287           nop->make_deopt();
2288         }
2289         // We can't assert here, there are some calls to stubs / runtime
2290         // that have reloc data and doesn't have a post call NOP.
2291         //assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
2292         break;
2293       }
2294       default:
2295         break;
2296     }
2297   }
2298   // Don't deopt this again.
2299   set_deoptimized_done();
2300 }
2301 
2302 void nmethod::verify_clean_inline_caches() {
2303   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
2304 
2305   ResourceMark rm;
2306   RelocIterator iter(this, oops_reloc_begin());
2307   while(iter.next()) {
2308     switch(iter.type()) {
2309       case relocInfo::virtual_call_type: {
2310         CompiledIC *ic = CompiledIC_at(&iter);
2311         CodeBlob *cb = CodeCache::find_blob(ic->destination());
2312         assert(cb != nullptr, "destination not in CodeBlob?");
2313         nmethod* nm = cb->as_nmethod_or_null();
2314         if (nm != nullptr) {
2315           // Verify that inline caches pointing to bad nmethods are clean
2316           if (!nm->is_in_use() || nm->is_unloading()) {
2317             assert(ic->is_clean(), "IC should be clean");
2318           }
2319         }
2320         break;
2321       }
2322       case relocInfo::static_call_type:
2323       case relocInfo::opt_virtual_call_type: {
2324         CompiledDirectCall *cdc = CompiledDirectCall::at(iter.reloc());
2325         CodeBlob *cb = CodeCache::find_blob(cdc->destination());
2326         assert(cb != nullptr, "destination not in CodeBlob?");
2327         nmethod* nm = cb->as_nmethod_or_null();
2328         if (nm != nullptr) {
2329           // Verify that inline caches pointing to bad nmethods are clean
2330           if (!nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
2331             assert(cdc->is_clean(), "IC should be clean");
2332           }
2333         }
2334         break;
2335       }
2336       default:
2337         break;
2338     }
2339   }
2340 }
2341 
2342 void nmethod::mark_as_maybe_on_stack() {
2343   AtomicAccess::store(&_gc_epoch, CodeCache::gc_epoch());
2344 }
2345 
2346 bool nmethod::is_maybe_on_stack() {
2347   // If the condition below is true, it means that the nmethod was found to
2348   // be alive the previous completed marking cycle.
2349   return AtomicAccess::load(&_gc_epoch) >= CodeCache::previous_completed_gc_marking_cycle();
2350 }
2351 
2352 void nmethod::inc_decompile_count() {
2353   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
2354   // Could be gated by ProfileTraps, but do not bother...
2355 #if INCLUDE_JVMCI
2356   if (jvmci_skip_profile_deopt()) {
2357     return;
2358   }
2359 #endif
2360   Method* m = method();
2361   if (m == nullptr)  return;
2362   MethodData* mdo = m->method_data();
2363   if (mdo == nullptr)  return;
2364   // There is a benign race here.  See comments in methodData.hpp.
2365   mdo->inc_decompile_count();
2366 }
2367 
2368 void nmethod::inc_method_profiling_count() {
2369   AtomicAccess::inc(&_method_profiling_count);
2370 }
2371 
2372 uint64_t nmethod::method_profiling_count() {
2373   return _method_profiling_count;
2374 }
2375 
2376 bool nmethod::try_transition(signed char new_state_int) {
2377   signed char new_state = new_state_int;
2378   assert_lock_strong(NMethodState_lock);
2379   signed char old_state = _state;
2380   if (old_state >= new_state) {
2381     // Ensure monotonicity of transitions.
2382     return false;
2383   }
2384   AtomicAccess::store(&_state, new_state);
2385   return true;
2386 }
2387 
2388 void nmethod::invalidate_osr_method() {
2389   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
2390   // Remove from list of active nmethods
2391   if (method() != nullptr) {
2392     method()->method_holder()->remove_osr_nmethod(this);
2393   }
2394 }
2395 
2396 void nmethod::log_state_change(InvalidationReason invalidation_reason) const {
2397   if (LogCompilation) {
2398     if (xtty != nullptr) {
2399       ttyLocker ttyl;  // keep the following output all in one block
2400       xtty->begin_elem("make_not_entrant thread='%zu' reason='%s'",
2401                        os::current_thread_id(), invalidation_reason_to_string(invalidation_reason));
2402       log_identity(xtty);
2403       xtty->stamp();
2404       xtty->end_elem();
2405     }
2406   }
2407 
2408   ResourceMark rm;
2409   stringStream ss(NEW_RESOURCE_ARRAY(char, 256), 256);
2410   ss.print("made not entrant: %s", invalidation_reason_to_string(invalidation_reason));
2411 
2412   CompileTask::print_ul(this, ss.freeze());
2413   if (PrintCompilation) {
2414     print_on_with_msg(tty, ss.freeze());
2415   }
2416 }
2417 
2418 void nmethod::unlink_from_method() {
2419   if (method() != nullptr) {
2420     method()->unlink_code(this);
2421   }
2422 }
2423 
2424 // Invalidate code
2425 bool nmethod::make_not_entrant(InvalidationReason invalidation_reason, bool keep_aot_entry) {
2426   // This can be called while the system is already at a safepoint which is ok
2427   NoSafepointVerifier nsv;
2428 
2429   if (is_unloading()) {
2430     // If the nmethod is unloading, then it is already not entrant through
2431     // the nmethod entry barriers. No need to do anything; GC will unload it.
2432     return false;
2433   }
2434 
2435   if (AtomicAccess::load(&_state) == not_entrant) {
2436     // Avoid taking the lock if already in required state.
2437     // This is safe from races because the state is an end-state,
2438     // which the nmethod cannot back out of once entered.
2439     // No need for fencing either.
2440     return false;
2441   }
2442 
2443   {
2444     // Enter critical section.  Does not block for safepoint.
2445     ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
2446 
2447     if (AtomicAccess::load(&_state) == not_entrant) {
2448       // another thread already performed this transition so nothing
2449       // to do, but return false to indicate this.
2450       return false;
2451     }
2452 
2453     if (is_osr_method()) {
2454       // This logic is equivalent to the logic below for patching the
2455       // verified entry point of regular methods.
2456       // this effectively makes the osr nmethod not entrant
2457       invalidate_osr_method();
2458     } else {
2459       // The caller can be calling the method statically or through an inline
2460       // cache call.
2461       BarrierSet::barrier_set()->barrier_set_nmethod()->make_not_entrant(this);
2462     }
2463 
2464     if (update_recompile_counts()) {
2465       // Mark the method as decompiled.
2466       inc_decompile_count();
2467     }
2468 
2469     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2470     if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2471       // If nmethod entry barriers are not supported, we won't mark
2472       // nmethods as on-stack when they become on-stack. So we
2473       // degrade to a less accurate flushing strategy, for now.
2474       mark_as_maybe_on_stack();
2475     }
2476 
2477     // Change state
2478     bool success = try_transition(not_entrant);
2479     assert(success, "Transition can't fail");
2480 
2481     // Log the transition once
2482     log_state_change(invalidation_reason);
2483 
2484     // Remove nmethod from method.
2485     unlink_from_method();
2486 
2487     if (!keep_aot_entry) {
2488       // Keep AOT code if it was simply replaced
2489       // otherwise make it not entrant too.
2490       AOTCodeCache::invalidate(_aot_code_entry);
2491     }
2492 
2493     CompileBroker::log_not_entrant(this);
2494   } // leave critical region under NMethodState_lock
2495 
2496 #if INCLUDE_JVMCI
2497   // Invalidate can't occur while holding the NMethodState_lock
2498   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2499   if (nmethod_data != nullptr) {
2500     nmethod_data->invalidate_nmethod_mirror(this, invalidation_reason);
2501   }
2502 #endif
2503 
2504 #ifdef ASSERT
2505   if (is_osr_method() && method() != nullptr) {
2506     // Make sure osr nmethod is invalidated, i.e. not on the list
2507     bool found = method()->method_holder()->remove_osr_nmethod(this);
2508     assert(!found, "osr nmethod should have been invalidated");
2509   }
2510 #endif
2511 
2512   return true;
2513 }
2514 
2515 // For concurrent GCs, there must be a handshake between unlink and flush
2516 void nmethod::unlink() {
2517   if (is_unlinked()) {
2518     // Already unlinked.
2519     return;
2520   }
2521 
2522   flush_dependencies();
2523 
2524   // unlink_from_method will take the NMethodState_lock.
2525   // In this case we don't strictly need it when unlinking nmethods from
2526   // the Method, because it is only concurrently unlinked by
2527   // the entry barrier, which acquires the per nmethod lock.
2528   unlink_from_method();
2529 
2530   if (is_osr_method()) {
2531     invalidate_osr_method();
2532   }
2533 
2534 #if INCLUDE_JVMCI
2535   // Clear the link between this nmethod and a HotSpotNmethod mirror
2536   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2537   if (nmethod_data != nullptr) {
2538     nmethod_data->invalidate_nmethod_mirror(this, is_cold() ?
2539             nmethod::InvalidationReason::UNLOADING_COLD :
2540             nmethod::InvalidationReason::UNLOADING);
2541   }
2542 #endif
2543 
2544   // Post before flushing as jmethodID is being used
2545   post_compiled_method_unload();
2546 
2547   // Register for flushing when it is safe. For concurrent class unloading,
2548   // that would be after the unloading handshake, and for STW class unloading
2549   // that would be when getting back to the VM thread.
2550   ClassUnloadingContext::context()->register_unlinked_nmethod(this);
2551 }
2552 
2553 void nmethod::purge(bool unregister_nmethod) {
2554 
2555   MutexLocker ml(CodeCache_lock, Mutex::_no_safepoint_check_flag);
2556 
2557   // completely deallocate this method
2558   Events::log_nmethod_flush(Thread::current(), "flushing %s nmethod " INTPTR_FORMAT, compile_kind(), p2i(this));
2559 
2560   LogTarget(Debug, codecache) lt;
2561   if (lt.is_enabled()) {
2562     ResourceMark rm;
2563     LogStream ls(lt);
2564     const char* method_name = method()->name()->as_C_string();
2565     const size_t codecache_capacity = CodeCache::capacity()/1024;
2566     const size_t codecache_free_space = CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024;
2567     ls.print("Flushing %s nmethod %6d/" INTPTR_FORMAT ", level=%d, cold=%d, epoch=" UINT64_FORMAT ", cold_count=" UINT64_FORMAT ". "
2568               "Cache capacity: %zuKb, free space: %zuKb. method %s (%s)",
2569               compile_kind(), _compile_id, p2i(this), _comp_level, is_cold(), _gc_epoch, CodeCache::cold_gc_count(),
2570               codecache_capacity, codecache_free_space, method_name, compiler_name());
2571   }
2572 
2573   // We need to deallocate any ExceptionCache data.
2574   // Note that we do not need to grab the nmethod lock for this, it
2575   // better be thread safe if we're disposing of it!
2576   ExceptionCache* ec = exception_cache();
2577   while(ec != nullptr) {
2578     ExceptionCache* next = ec->next();
2579     delete ec;
2580     ec = next;
2581   }
2582   if (_pc_desc_container != nullptr) {
2583     delete _pc_desc_container;
2584   }
2585   if (_compiled_ic_data != nullptr) {
2586     delete[] _compiled_ic_data;
2587   }
2588 
2589   if (_immutable_data != blob_end() && !AOTCodeCache::is_address_in_aot_cache((address)_oop_maps)) {
2590     int reference_count = get_immutable_data_references_counter();
2591     assert(reference_count > 0, "immutable data has no references");
2592 
2593     set_immutable_data_references_counter(reference_count - 1);
2594     // Free memory if this is the last nmethod referencing immutable data
2595     if (reference_count == 0) {
2596       os::free(_immutable_data);
2597     }
2598 
2599     _immutable_data = blob_end(); // Valid not null address
2600   }
2601 
2602   if (unregister_nmethod) {
2603     Universe::heap()->unregister_nmethod(this);
2604   }
2605   CodeCache::unregister_old_nmethod(this);
2606 
2607   JVMCI_ONLY( _metadata_size = 0; )
2608   CodeBlob::purge();
2609 }
2610 
2611 oop nmethod::oop_at(int index) const {
2612   if (index == 0) {
2613     return nullptr;
2614   }
2615 
2616   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2617   return bs_nm->oop_load_no_keepalive(this, index);
2618 }
2619 
2620 oop nmethod::oop_at_phantom(int index) const {
2621   if (index == 0) {
2622     return nullptr;
2623   }
2624 
2625   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2626   return bs_nm->oop_load_phantom(this, index);
2627 }
2628 
2629 //
2630 // Notify all classes this nmethod is dependent on that it is no
2631 // longer dependent.
2632 
2633 void nmethod::flush_dependencies() {
2634   if (!has_flushed_dependencies()) {
2635     set_has_flushed_dependencies(true);
2636     for (Dependencies::DepStream deps(this); deps.next(); ) {
2637       if (deps.type() == Dependencies::call_site_target_value) {
2638         // CallSite dependencies are managed on per-CallSite instance basis.
2639         oop call_site = deps.argument_oop(0);
2640         MethodHandles::clean_dependency_context(call_site);
2641       } else {
2642         InstanceKlass* ik = deps.context_type();
2643         if (ik == nullptr) {
2644           continue;  // ignore things like evol_method
2645         }
2646         // During GC liveness of dependee determines class that needs to be updated.
2647         // The GC may clean dependency contexts concurrently and in parallel.
2648         ik->clean_dependency_context();
2649       }
2650     }
2651   }
2652 }
2653 
2654 void nmethod::post_compiled_method(CompileTask* task) {
2655   task->mark_success();
2656   task->set_nm_content_size(content_size());
2657   task->set_nm_insts_size(insts_size());
2658   task->set_nm_total_size(total_size());
2659 
2660   // task->is_aot_load() is true only for loaded AOT code.
2661   // nmethod::_aot_code_entry is set for loaded and stored AOT code
2662   // to invalidate the entry when nmethod is deoptimized.
2663   // VerifyAOTCode is option to not store in archive AOT code.
2664   guarantee((_aot_code_entry != nullptr) || !task->is_aot_load() || VerifyAOTCode, "sanity");
2665 
2666   // JVMTI -- compiled method notification (must be done outside lock)
2667   post_compiled_method_load_event();
2668 
2669   if (CompilationLog::log() != nullptr) {
2670     CompilationLog::log()->log_nmethod(JavaThread::current(), this);
2671   }
2672 
2673   const DirectiveSet* directive = task->directive();
2674   maybe_print_nmethod(directive);
2675 }
2676 
2677 // ------------------------------------------------------------------
2678 // post_compiled_method_load_event
2679 // new method for install_code() path
2680 // Transfer information from compilation to jvmti
2681 void nmethod::post_compiled_method_load_event(JvmtiThreadState* state) {
2682   // This is a bad time for a safepoint.  We don't want
2683   // this nmethod to get unloaded while we're queueing the event.
2684   NoSafepointVerifier nsv;
2685 
2686   Method* m = method();
2687   HOTSPOT_COMPILED_METHOD_LOAD(
2688       (char *) m->klass_name()->bytes(),
2689       m->klass_name()->utf8_length(),
2690       (char *) m->name()->bytes(),
2691       m->name()->utf8_length(),
2692       (char *) m->signature()->bytes(),
2693       m->signature()->utf8_length(),
2694       insts_begin(), insts_size());
2695 
2696 
2697   if (JvmtiExport::should_post_compiled_method_load()) {
2698     // Only post unload events if load events are found.
2699     set_load_reported();
2700     // If a JavaThread hasn't been passed in, let the Service thread
2701     // (which is a real Java thread) post the event
2702     JvmtiDeferredEvent event = JvmtiDeferredEvent::compiled_method_load_event(this);
2703     if (state == nullptr) {
2704       // Execute any barrier code for this nmethod as if it's called, since
2705       // keeping it alive looks like stack walking.
2706       run_nmethod_entry_barrier();
2707       ServiceThread::enqueue_deferred_event(&event);
2708     } else {
2709       // This enters the nmethod barrier outside in the caller.
2710       state->enqueue_event(&event);
2711     }
2712   }
2713 }
2714 
2715 void nmethod::post_compiled_method_unload() {
2716   assert(_method != nullptr, "just checking");
2717   DTRACE_METHOD_UNLOAD_PROBE(method());
2718 
2719   // If a JVMTI agent has enabled the CompiledMethodUnload event then
2720   // post the event. The Method* will not be valid when this is freed.
2721 
2722   // Don't bother posting the unload if the load event wasn't posted.
2723   if (load_reported() && JvmtiExport::should_post_compiled_method_unload()) {
2724     JvmtiDeferredEvent event =
2725       JvmtiDeferredEvent::compiled_method_unload_event(
2726           method()->jmethod_id(), insts_begin());
2727     ServiceThread::enqueue_deferred_event(&event);
2728   }
2729 }
2730 
2731 // Iterate over metadata calling this function.   Used by RedefineClasses
2732 void nmethod::metadata_do(MetadataClosure* f) {
2733   {
2734     // Visit all immediate references that are embedded in the instruction stream.
2735     RelocIterator iter(this, oops_reloc_begin());
2736     while (iter.next()) {
2737       if (iter.type() == relocInfo::metadata_type) {
2738         metadata_Relocation* r = iter.metadata_reloc();
2739         // In this metadata, we must only follow those metadatas directly embedded in
2740         // the code.  Other metadatas (oop_index>0) are seen as part of
2741         // the metadata section below.
2742         assert(1 == (r->metadata_is_immediate()) +
2743                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2744                "metadata must be found in exactly one place");
2745         if (r->metadata_is_immediate() && r->metadata_value() != nullptr) {
2746           Metadata* md = r->metadata_value();
2747           if (md != _method) f->do_metadata(md);
2748         }
2749       } else if (iter.type() == relocInfo::virtual_call_type) {
2750         // Check compiledIC holders associated with this nmethod
2751         ResourceMark rm;
2752         CompiledIC *ic = CompiledIC_at(&iter);
2753         ic->metadata_do(f);
2754       }
2755     }
2756   }
2757 
2758   // Visit the metadata section
2759   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2760     if (*p == Universe::non_oop_word() || *p == nullptr)  continue;  // skip non-oops
2761     Metadata* md = *p;
2762     f->do_metadata(md);
2763   }
2764 
2765   // Visit metadata not embedded in the other places.
2766   if (_method != nullptr) f->do_metadata(_method);
2767 }
2768 
2769 // Heuristic for nuking nmethods even though their oops are live.
2770 // Main purpose is to reduce code cache pressure and get rid of
2771 // nmethods that don't seem to be all that relevant any longer.
2772 bool nmethod::is_cold() {
2773   if (!MethodFlushing || is_native_method() || is_not_installed()) {
2774     // No heuristic unloading at all
2775     return false;
2776   }
2777 
2778   if (!is_maybe_on_stack() && is_not_entrant()) {
2779     // Not entrant nmethods that are not on any stack can just
2780     // be removed
2781     return true;
2782   }
2783 
2784   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2785   if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2786     // On platforms that don't support nmethod entry barriers, we can't
2787     // trust the temporal aspect of the gc epochs. So we can't detect
2788     // cold nmethods on such platforms.
2789     return false;
2790   }
2791 
2792   if (!UseCodeCacheFlushing) {
2793     // Bail out if we don't heuristically remove nmethods
2794     return false;
2795   }
2796 
2797   // Other code can be phased out more gradually after N GCs
2798   return CodeCache::previous_completed_gc_marking_cycle() > _gc_epoch + 2 * CodeCache::cold_gc_count();
2799 }
2800 
2801 // The _is_unloading_state encodes a tuple comprising the unloading cycle
2802 // and the result of IsUnloadingBehaviour::is_unloading() for that cycle.
2803 // This is the bit layout of the _is_unloading_state byte: 00000CCU
2804 // CC refers to the cycle, which has 2 bits, and U refers to the result of
2805 // IsUnloadingBehaviour::is_unloading() for that unloading cycle.
2806 
2807 class IsUnloadingState: public AllStatic {
2808   static const uint8_t _is_unloading_mask = 1;
2809   static const uint8_t _is_unloading_shift = 0;
2810   static const uint8_t _unloading_cycle_mask = 6;
2811   static const uint8_t _unloading_cycle_shift = 1;
2812 
2813   static uint8_t set_is_unloading(uint8_t state, bool value) {
2814     state &= (uint8_t)~_is_unloading_mask;
2815     if (value) {
2816       state |= 1 << _is_unloading_shift;
2817     }
2818     assert(is_unloading(state) == value, "unexpected unloading cycle overflow");
2819     return state;
2820   }
2821 
2822   static uint8_t set_unloading_cycle(uint8_t state, uint8_t value) {
2823     state &= (uint8_t)~_unloading_cycle_mask;
2824     state |= (uint8_t)(value << _unloading_cycle_shift);
2825     assert(unloading_cycle(state) == value, "unexpected unloading cycle overflow");
2826     return state;
2827   }
2828 
2829 public:
2830   static bool is_unloading(uint8_t state) { return (state & _is_unloading_mask) >> _is_unloading_shift == 1; }
2831   static uint8_t unloading_cycle(uint8_t state) { return (state & _unloading_cycle_mask) >> _unloading_cycle_shift; }
2832 
2833   static uint8_t create(bool is_unloading, uint8_t unloading_cycle) {
2834     uint8_t state = 0;
2835     state = set_is_unloading(state, is_unloading);
2836     state = set_unloading_cycle(state, unloading_cycle);
2837     return state;
2838   }
2839 };
2840 
2841 bool nmethod::is_unloading() {
2842   uint8_t state = AtomicAccess::load(&_is_unloading_state);
2843   bool state_is_unloading = IsUnloadingState::is_unloading(state);
2844   if (state_is_unloading) {
2845     return true;
2846   }
2847   uint8_t state_unloading_cycle = IsUnloadingState::unloading_cycle(state);
2848   uint8_t current_cycle = CodeCache::unloading_cycle();
2849   if (state_unloading_cycle == current_cycle) {
2850     return false;
2851   }
2852 
2853   // The IsUnloadingBehaviour is responsible for calculating if the nmethod
2854   // should be unloaded. This can be either because there is a dead oop,
2855   // or because is_cold() heuristically determines it is time to unload.
2856   state_unloading_cycle = current_cycle;
2857   state_is_unloading = IsUnloadingBehaviour::is_unloading(this);
2858   uint8_t new_state = IsUnloadingState::create(state_is_unloading, state_unloading_cycle);
2859 
2860   // Note that if an nmethod has dead oops, everyone will agree that the
2861   // nmethod is_unloading. However, the is_cold heuristics can yield
2862   // different outcomes, so we guard the computed result with a CAS
2863   // to ensure all threads have a shared view of whether an nmethod
2864   // is_unloading or not.
2865   uint8_t found_state = AtomicAccess::cmpxchg(&_is_unloading_state, state, new_state, memory_order_relaxed);
2866 
2867   if (found_state == state) {
2868     // First to change state, we win
2869     return state_is_unloading;
2870   } else {
2871     // State already set, so use it
2872     return IsUnloadingState::is_unloading(found_state);
2873   }
2874 }
2875 
2876 void nmethod::clear_unloading_state() {
2877   uint8_t state = IsUnloadingState::create(false, CodeCache::unloading_cycle());
2878   AtomicAccess::store(&_is_unloading_state, state);
2879 }
2880 
2881 
2882 // This is called at the end of the strong tracing/marking phase of a
2883 // GC to unload an nmethod if it contains otherwise unreachable
2884 // oops or is heuristically found to be not important.
2885 void nmethod::do_unloading(bool unloading_occurred) {
2886   // Make sure the oop's ready to receive visitors
2887   if (is_unloading()) {
2888     unlink();
2889   } else {
2890     unload_nmethod_caches(unloading_occurred);
2891     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2892     if (bs_nm != nullptr) {
2893       bs_nm->disarm(this);
2894     }
2895   }
2896 }
2897 
2898 void nmethod::oops_do(OopClosure* f) {
2899   // Prevent extra code cache walk for platforms that don't have immediate oops.
2900   if (relocInfo::mustIterateImmediateOopsInCode()) {
2901     RelocIterator iter(this, oops_reloc_begin());
2902 
2903     while (iter.next()) {
2904       if (iter.type() == relocInfo::oop_type ) {
2905         oop_Relocation* r = iter.oop_reloc();
2906         // In this loop, we must only follow those oops directly embedded in
2907         // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
2908         assert(1 == (r->oop_is_immediate()) +
2909                (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2910                "oop must be found in exactly one place");
2911         if (r->oop_is_immediate() && r->oop_value() != nullptr) {
2912           f->do_oop(r->oop_addr());
2913         }
2914       }
2915     }
2916   }
2917 
2918   // Scopes
2919   // This includes oop constants not inlined in the code stream.
2920   for (oop* p = oops_begin(); p < oops_end(); p++) {
2921     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
2922     f->do_oop(p);
2923   }
2924 }
2925 
2926 void nmethod::follow_nmethod(OopIterateClosure* cl) {
2927   // Process oops in the nmethod
2928   oops_do(cl);
2929 
2930   // CodeCache unloading support
2931   mark_as_maybe_on_stack();
2932 
2933   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2934   bs_nm->disarm(this);
2935 
2936   // There's an assumption made that this function is not used by GCs that
2937   // relocate objects, and therefore we don't call fix_oop_relocations.
2938 }
2939 
2940 nmethod* volatile nmethod::_oops_do_mark_nmethods;
2941 
2942 void nmethod::oops_do_log_change(const char* state) {
2943   LogTarget(Trace, gc, nmethod) lt;
2944   if (lt.is_enabled()) {
2945     LogStream ls(lt);
2946     CompileTask::print(&ls, this, state, true /* short_form */);
2947   }
2948 }
2949 
2950 bool nmethod::oops_do_try_claim() {
2951   if (oops_do_try_claim_weak_request()) {
2952     nmethod* result = oops_do_try_add_to_list_as_weak_done();
2953     assert(result == nullptr, "adding to global list as weak done must always succeed.");
2954     return true;
2955   }
2956   return false;
2957 }
2958 
2959 bool nmethod::oops_do_try_claim_weak_request() {
2960   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2961 
2962   if ((_oops_do_mark_link == nullptr) &&
2963       (AtomicAccess::replace_if_null(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag)))) {
2964     oops_do_log_change("oops_do, mark weak request");
2965     return true;
2966   }
2967   return false;
2968 }
2969 
2970 void nmethod::oops_do_set_strong_done(nmethod* old_head) {
2971   _oops_do_mark_link = mark_link(old_head, claim_strong_done_tag);
2972 }
2973 
2974 nmethod::oops_do_mark_link* nmethod::oops_do_try_claim_strong_done() {
2975   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2976 
2977   oops_do_mark_link* old_next = AtomicAccess::cmpxchg(&_oops_do_mark_link, mark_link(nullptr, claim_weak_request_tag), mark_link(this, claim_strong_done_tag));
2978   if (old_next == nullptr) {
2979     oops_do_log_change("oops_do, mark strong done");
2980   }
2981   return old_next;
2982 }
2983 
2984 nmethod::oops_do_mark_link* nmethod::oops_do_try_add_strong_request(nmethod::oops_do_mark_link* next) {
2985   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2986   assert(next == mark_link(this, claim_weak_request_tag), "Should be claimed as weak");
2987 
2988   oops_do_mark_link* old_next = AtomicAccess::cmpxchg(&_oops_do_mark_link, next, mark_link(this, claim_strong_request_tag));
2989   if (old_next == next) {
2990     oops_do_log_change("oops_do, mark strong request");
2991   }
2992   return old_next;
2993 }
2994 
2995 bool nmethod::oops_do_try_claim_weak_done_as_strong_done(nmethod::oops_do_mark_link* next) {
2996   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2997   assert(extract_state(next) == claim_weak_done_tag, "Should be claimed as weak done");
2998 
2999   oops_do_mark_link* old_next = AtomicAccess::cmpxchg(&_oops_do_mark_link, next, mark_link(extract_nmethod(next), claim_strong_done_tag));
3000   if (old_next == next) {
3001     oops_do_log_change("oops_do, mark weak done -> mark strong done");
3002     return true;
3003   }
3004   return false;
3005 }
3006 
3007 nmethod* nmethod::oops_do_try_add_to_list_as_weak_done() {
3008   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
3009 
3010   assert(extract_state(_oops_do_mark_link) == claim_weak_request_tag ||
3011          extract_state(_oops_do_mark_link) == claim_strong_request_tag,
3012          "must be but is nmethod " PTR_FORMAT " %u", p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
3013 
3014   nmethod* old_head = AtomicAccess::xchg(&_oops_do_mark_nmethods, this);
3015   // Self-loop if needed.
3016   if (old_head == nullptr) {
3017     old_head = this;
3018   }
3019   // Try to install end of list and weak done tag.
3020   if (AtomicAccess::cmpxchg(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag), mark_link(old_head, claim_weak_done_tag)) == mark_link(this, claim_weak_request_tag)) {
3021     oops_do_log_change("oops_do, mark weak done");
3022     return nullptr;
3023   } else {
3024     return old_head;
3025   }
3026 }
3027 
3028 void nmethod::oops_do_add_to_list_as_strong_done() {
3029   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
3030 
3031   nmethod* old_head = AtomicAccess::xchg(&_oops_do_mark_nmethods, this);
3032   // Self-loop if needed.
3033   if (old_head == nullptr) {
3034     old_head = this;
3035   }
3036   assert(_oops_do_mark_link == mark_link(this, claim_strong_done_tag), "must be but is nmethod " PTR_FORMAT " state %u",
3037          p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
3038 
3039   oops_do_set_strong_done(old_head);
3040 }
3041 
3042 void nmethod::oops_do_process_weak(OopsDoProcessor* p) {
3043   if (!oops_do_try_claim_weak_request()) {
3044     // Failed to claim for weak processing.
3045     oops_do_log_change("oops_do, mark weak request fail");
3046     return;
3047   }
3048 
3049   p->do_regular_processing(this);
3050 
3051   nmethod* old_head = oops_do_try_add_to_list_as_weak_done();
3052   if (old_head == nullptr) {
3053     return;
3054   }
3055   oops_do_log_change("oops_do, mark weak done fail");
3056   // Adding to global list failed, another thread added a strong request.
3057   assert(extract_state(_oops_do_mark_link) == claim_strong_request_tag,
3058          "must be but is %u", extract_state(_oops_do_mark_link));
3059 
3060   oops_do_log_change("oops_do, mark weak request -> mark strong done");
3061 
3062   oops_do_set_strong_done(old_head);
3063   // Do missing strong processing.
3064   p->do_remaining_strong_processing(this);
3065 }
3066 
3067 void nmethod::oops_do_process_strong(OopsDoProcessor* p) {
3068   oops_do_mark_link* next_raw = oops_do_try_claim_strong_done();
3069   if (next_raw == nullptr) {
3070     p->do_regular_processing(this);
3071     oops_do_add_to_list_as_strong_done();
3072     return;
3073   }
3074   // Claim failed. Figure out why and handle it.
3075   if (oops_do_has_weak_request(next_raw)) {
3076     oops_do_mark_link* old = next_raw;
3077     // Claim failed because being weak processed (state == "weak request").
3078     // Try to request deferred strong processing.
3079     next_raw = oops_do_try_add_strong_request(old);
3080     if (next_raw == old) {
3081       // Successfully requested deferred strong processing.
3082       return;
3083     }
3084     // Failed because of a concurrent transition. No longer in "weak request" state.
3085   }
3086   if (oops_do_has_any_strong_state(next_raw)) {
3087     // Already claimed for strong processing or requested for such.
3088     return;
3089   }
3090   if (oops_do_try_claim_weak_done_as_strong_done(next_raw)) {
3091     // Successfully claimed "weak done" as "strong done". Do the missing marking.
3092     p->do_remaining_strong_processing(this);
3093     return;
3094   }
3095   // Claim failed, some other thread got it.
3096 }
3097 
3098 void nmethod::oops_do_marking_prologue() {
3099   assert_at_safepoint();
3100 
3101   log_trace(gc, nmethod)("oops_do_marking_prologue");
3102   assert(_oops_do_mark_nmethods == nullptr, "must be empty");
3103 }
3104 
3105 void nmethod::oops_do_marking_epilogue() {
3106   assert_at_safepoint();
3107 
3108   nmethod* next = _oops_do_mark_nmethods;
3109   _oops_do_mark_nmethods = nullptr;
3110   if (next != nullptr) {
3111     nmethod* cur;
3112     do {
3113       cur = next;
3114       next = extract_nmethod(cur->_oops_do_mark_link);
3115       cur->_oops_do_mark_link = nullptr;
3116       DEBUG_ONLY(cur->verify_oop_relocations());
3117 
3118       LogTarget(Trace, gc, nmethod) lt;
3119       if (lt.is_enabled()) {
3120         LogStream ls(lt);
3121         CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
3122       }
3123       // End if self-loop has been detected.
3124     } while (cur != next);
3125   }
3126   log_trace(gc, nmethod)("oops_do_marking_epilogue");
3127 }
3128 
3129 inline bool includes(void* p, void* from, void* to) {
3130   return from <= p && p < to;
3131 }
3132 
3133 
3134 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
3135   assert(count >= 2, "must be sentinel values, at least");
3136 
3137 #ifdef ASSERT
3138   // must be sorted and unique; we do a binary search in find_pc_desc()
3139   int prev_offset = pcs[0].pc_offset();
3140   assert(prev_offset == PcDesc::lower_offset_limit,
3141          "must start with a sentinel");
3142   for (int i = 1; i < count; i++) {
3143     int this_offset = pcs[i].pc_offset();
3144     assert(this_offset > prev_offset, "offsets must be sorted");
3145     prev_offset = this_offset;
3146   }
3147   assert(prev_offset == PcDesc::upper_offset_limit,
3148          "must end with a sentinel");
3149 #endif //ASSERT
3150 
3151   int size = count * sizeof(PcDesc);
3152   assert(scopes_pcs_size() >= size, "oob");
3153   memcpy(scopes_pcs_begin(), pcs, size);
3154 
3155   // Adjust the final sentinel downward.
3156   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
3157   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
3158   last_pc->set_pc_offset(content_size() + 1);
3159   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
3160     // Fill any rounding gaps with copies of the last record.
3161     last_pc[1] = last_pc[0];
3162   }
3163   // The following assert could fail if sizeof(PcDesc) is not
3164   // an integral multiple of oopSize (the rounding term).
3165   // If it fails, change the logic to always allocate a multiple
3166   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
3167   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
3168 }
3169 
3170 void nmethod::copy_scopes_data(u_char* buffer, int size) {
3171   assert(scopes_data_size() >= size, "oob");
3172   memcpy(scopes_data_begin(), buffer, size);
3173 }
3174 
3175 #ifdef ASSERT
3176 static PcDesc* linear_search(int pc_offset, bool approximate, PcDesc* lower, PcDesc* upper) {
3177   PcDesc* res = nullptr;
3178   assert(lower != nullptr && lower->pc_offset() == PcDesc::lower_offset_limit,
3179          "must start with a sentinel");
3180   // lower + 1 to exclude initial sentinel
3181   for (PcDesc* p = lower + 1; p < upper; p++) {
3182     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
3183     if (match_desc(p, pc_offset, approximate)) {
3184       if (res == nullptr) {
3185         res = p;
3186       } else {
3187         res = (PcDesc*) badAddress;
3188       }
3189     }
3190   }
3191   return res;
3192 }
3193 #endif
3194 
3195 
3196 #ifndef PRODUCT
3197 // Version of method to collect statistic
3198 PcDesc* PcDescContainer::find_pc_desc(address pc, bool approximate, address code_begin,
3199                                       PcDesc* lower, PcDesc* upper) {
3200   ++pc_nmethod_stats.pc_desc_queries;
3201   if (approximate) ++pc_nmethod_stats.pc_desc_approx;
3202 
3203   PcDesc* desc = _pc_desc_cache.last_pc_desc();
3204   assert(desc != nullptr, "PcDesc cache should be initialized already");
3205   if (desc->pc_offset() == (pc - code_begin)) {
3206     // Cached value matched
3207     ++pc_nmethod_stats.pc_desc_tests;
3208     ++pc_nmethod_stats.pc_desc_repeats;
3209     return desc;
3210   }
3211   return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
3212 }
3213 #endif
3214 
3215 // Finds a PcDesc with real-pc equal to "pc"
3216 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, address code_begin,
3217                                                PcDesc* lower_incl, PcDesc* upper_incl) {
3218   if ((pc < code_begin) ||
3219       (pc - code_begin) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
3220     return nullptr;  // PC is wildly out of range
3221   }
3222   int pc_offset = (int) (pc - code_begin);
3223 
3224   // Check the PcDesc cache if it contains the desired PcDesc
3225   // (This as an almost 100% hit rate.)
3226   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
3227   if (res != nullptr) {
3228     assert(res == linear_search(pc_offset, approximate, lower_incl, upper_incl), "cache ok");
3229     return res;
3230   }
3231 
3232   // Fallback algorithm: quasi-linear search for the PcDesc
3233   // Find the last pc_offset less than the given offset.
3234   // The successor must be the required match, if there is a match at all.
3235   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
3236   PcDesc* lower = lower_incl;     // this is initial sentinel
3237   PcDesc* upper = upper_incl - 1; // exclude final sentinel
3238   if (lower >= upper)  return nullptr;  // no PcDescs at all
3239 
3240 #define assert_LU_OK \
3241   /* invariant on lower..upper during the following search: */ \
3242   assert(lower->pc_offset() <  pc_offset, "sanity"); \
3243   assert(upper->pc_offset() >= pc_offset, "sanity")
3244   assert_LU_OK;
3245 
3246   // Use the last successful return as a split point.
3247   PcDesc* mid = _pc_desc_cache.last_pc_desc();
3248   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
3249   if (mid->pc_offset() < pc_offset) {
3250     lower = mid;
3251   } else {
3252     upper = mid;
3253   }
3254 
3255   // Take giant steps at first (4096, then 256, then 16, then 1)
3256   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ DEBUG_ONLY(-1);
3257   const int RADIX = (1 << LOG2_RADIX);
3258   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
3259     while ((mid = lower + step) < upper) {
3260       assert_LU_OK;
3261       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
3262       if (mid->pc_offset() < pc_offset) {
3263         lower = mid;
3264       } else {
3265         upper = mid;
3266         break;
3267       }
3268     }
3269     assert_LU_OK;
3270   }
3271 
3272   // Sneak up on the value with a linear search of length ~16.
3273   while (true) {
3274     assert_LU_OK;
3275     mid = lower + 1;
3276     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
3277     if (mid->pc_offset() < pc_offset) {
3278       lower = mid;
3279     } else {
3280       upper = mid;
3281       break;
3282     }
3283   }
3284 #undef assert_LU_OK
3285 
3286   if (match_desc(upper, pc_offset, approximate)) {
3287     assert(upper == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
3288     if (!Thread::current_in_asgct()) {
3289       // we don't want to modify the cache if we're in ASGCT
3290       // which is typically called in a signal handler
3291       _pc_desc_cache.add_pc_desc(upper);
3292     }
3293     return upper;
3294   } else {
3295     assert(nullptr == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
3296     return nullptr;
3297   }
3298 }
3299 
3300 bool nmethod::check_dependency_on(DepChange& changes) {
3301   // What has happened:
3302   // 1) a new class dependee has been added
3303   // 2) dependee and all its super classes have been marked
3304   bool found_check = false;  // set true if we are upset
3305   for (Dependencies::DepStream deps(this); deps.next(); ) {
3306     // Evaluate only relevant dependencies.
3307     if (deps.spot_check_dependency_at(changes) != nullptr) {
3308       found_check = true;
3309       NOT_DEBUG(break);
3310     }
3311   }
3312   return found_check;
3313 }
3314 
3315 // Called from mark_for_deoptimization, when dependee is invalidated.
3316 bool nmethod::is_dependent_on_method(Method* dependee) {
3317   for (Dependencies::DepStream deps(this); deps.next(); ) {
3318     if (deps.type() != Dependencies::evol_method)
3319       continue;
3320     Method* method = deps.method_argument(0);
3321     if (method == dependee) return true;
3322   }
3323   return false;
3324 }
3325 
3326 void nmethod_init() {
3327   // make sure you didn't forget to adjust the filler fields
3328   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
3329 }
3330 
3331 // -----------------------------------------------------------------------------
3332 // Verification
3333 
3334 class VerifyOopsClosure: public OopClosure {
3335   nmethod* _nm;
3336   bool     _ok;
3337 public:
3338   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
3339   bool ok() { return _ok; }
3340   virtual void do_oop(oop* p) {
3341     if (oopDesc::is_oop_or_null(*p)) return;
3342     // Print diagnostic information before calling print_nmethod().
3343     // Assertions therein might prevent call from returning.
3344     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
3345                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
3346     if (_ok) {
3347       _nm->print_nmethod(true);
3348       _ok = false;
3349     }
3350   }
3351   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
3352 };
3353 
3354 class VerifyMetadataClosure: public MetadataClosure {
3355  public:
3356   void do_metadata(Metadata* md) {
3357     if (md->is_method()) {
3358       Method* method = (Method*)md;
3359       assert(!method->is_old(), "Should not be installing old methods");
3360     }
3361   }
3362 };
3363 
3364 
3365 void nmethod::verify() {
3366   if (is_not_entrant())
3367     return;
3368 
3369   // assert(oopDesc::is_oop(method()), "must be valid");
3370 
3371   ResourceMark rm;
3372 
3373   if (!CodeCache::contains(this)) {
3374     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
3375   }
3376 
3377   if(is_native_method() )
3378     return;
3379 
3380   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
3381   if (nm != this) {
3382     fatal("find_nmethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
3383   }
3384 
3385   // Verification can triggered during shutdown after AOTCodeCache is closed.
3386   // If the Scopes data is in the AOT code cache, then we should avoid verification during shutdown.
3387   if (!is_aot() || AOTCodeCache::is_on()) {
3388     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3389       if (! p->verify(this)) {
3390         tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
3391       }
3392     }
3393 
3394 #ifdef ASSERT
3395 #if INCLUDE_JVMCI
3396     {
3397       // Verify that implicit exceptions that deoptimize have a PcDesc and OopMap
3398       ImmutableOopMapSet* oms = oop_maps();
3399       ImplicitExceptionTable implicit_table(this);
3400       for (uint i = 0; i < implicit_table.len(); i++) {
3401         int exec_offset = (int) implicit_table.get_exec_offset(i);
3402         if (implicit_table.get_exec_offset(i) == implicit_table.get_cont_offset(i)) {
3403           assert(pc_desc_at(code_begin() + exec_offset) != nullptr, "missing PcDesc");
3404           bool found = false;
3405           for (int i = 0, imax = oms->count(); i < imax; i++) {
3406             if (oms->pair_at(i)->pc_offset() == exec_offset) {
3407               found = true;
3408               break;
3409             }
3410           }
3411           assert(found, "missing oopmap");
3412         }
3413       }
3414     }
3415 #endif
3416 #endif
3417   }
3418 
3419   VerifyOopsClosure voc(this);
3420   oops_do(&voc);
3421   assert(voc.ok(), "embedded oops must be OK");
3422   Universe::heap()->verify_nmethod(this);
3423 
3424   assert(_oops_do_mark_link == nullptr, "_oops_do_mark_link for %s should be nullptr but is " PTR_FORMAT,
3425          nm->method()->external_name(), p2i(_oops_do_mark_link));
3426   if (!is_aot() || AOTCodeCache::is_on()) {
3427     verify_scopes();
3428   }
3429 
3430   CompiledICLocker nm_verify(this);
3431   VerifyMetadataClosure vmc;
3432   metadata_do(&vmc);
3433 }
3434 
3435 
3436 void nmethod::verify_interrupt_point(address call_site, bool is_inline_cache) {
3437 
3438   // Verify IC only when nmethod installation is finished.
3439   if (!is_not_installed()) {
3440     if (CompiledICLocker::is_safe(this)) {
3441       if (is_inline_cache) {
3442         CompiledIC_at(this, call_site);
3443       } else {
3444         CompiledDirectCall::at(call_site);
3445       }
3446     } else {
3447       CompiledICLocker ml_verify(this);
3448       if (is_inline_cache) {
3449         CompiledIC_at(this, call_site);
3450       } else {
3451         CompiledDirectCall::at(call_site);
3452       }
3453     }
3454   }
3455 
3456   HandleMark hm(Thread::current());
3457 
3458   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
3459   assert(pd != nullptr, "PcDesc must exist");
3460   for (ScopeDesc* sd = new ScopeDesc(this, pd);
3461        !sd->is_top(); sd = sd->sender()) {
3462     sd->verify();
3463   }
3464 }
3465 
3466 void nmethod::verify_scopes() {
3467   if( !method() ) return;       // Runtime stubs have no scope
3468   if (method()->is_native()) return; // Ignore stub methods.
3469   // iterate through all interrupt point
3470   // and verify the debug information is valid.
3471   RelocIterator iter(this);
3472   while (iter.next()) {
3473     address stub = nullptr;
3474     switch (iter.type()) {
3475       case relocInfo::virtual_call_type:
3476         verify_interrupt_point(iter.addr(), true /* is_inline_cache */);
3477         break;
3478       case relocInfo::opt_virtual_call_type:
3479         stub = iter.opt_virtual_call_reloc()->static_stub();
3480         verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3481         break;
3482       case relocInfo::static_call_type:
3483         stub = iter.static_call_reloc()->static_stub();
3484         verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3485         break;
3486       case relocInfo::runtime_call_type:
3487       case relocInfo::runtime_call_w_cp_type: {
3488         address destination = iter.reloc()->value();
3489         // Right now there is no way to find out which entries support
3490         // an interrupt point.  It would be nice if we had this
3491         // information in a table.
3492         break;
3493       }
3494       default:
3495         break;
3496     }
3497     assert(stub == nullptr || stub_contains(stub), "static call stub outside stub section");
3498   }
3499 }
3500 
3501 
3502 // -----------------------------------------------------------------------------
3503 // Printing operations
3504 
3505 void nmethod::print_on_impl(outputStream* st) const {
3506   ResourceMark rm;
3507 
3508   st->print("Compiled method ");
3509 
3510   if (is_compiled_by_c1()) {
3511     st->print("(c1) ");
3512   } else if (is_compiled_by_c2()) {
3513     st->print("(c2) ");
3514   } else if (is_compiled_by_jvmci()) {
3515     st->print("(JVMCI) ");
3516   } else {
3517     st->print("(n/a) ");
3518   }
3519 
3520   print_on_with_msg(st, nullptr);
3521 
3522   if (WizardMode) {
3523     st->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
3524     st->print(" for method " INTPTR_FORMAT , p2i(method()));
3525     st->print(" { ");
3526     st->print_cr("%s ", state());
3527     st->print_cr("}:");
3528   }
3529   if (size              () > 0) st->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3530                                              p2i(this),
3531                                              p2i(this) + size(),
3532                                              size());
3533   if (consts_size       () > 0) st->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3534                                              p2i(consts_begin()),
3535                                              p2i(consts_end()),
3536                                              consts_size());
3537   if (insts_size        () > 0) st->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3538                                              p2i(insts_begin()),
3539                                              p2i(insts_end()),
3540                                              insts_size());
3541   if (stub_size         () > 0) st->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3542                                              p2i(stub_begin()),
3543                                              p2i(stub_end()),
3544                                              stub_size());
3545   if (oops_size         () > 0) st->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3546                                              p2i(oops_begin()),
3547                                              p2i(oops_end()),
3548                                              oops_size());
3549   if (mutable_data_size() > 0) st->print_cr(" mutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3550                                              p2i(mutable_data_begin()),
3551                                              p2i(mutable_data_end()),
3552                                              mutable_data_size());
3553   if (relocation_size() > 0)   st->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3554                                              p2i(relocation_begin()),
3555                                              p2i(relocation_end()),
3556                                              relocation_size());
3557   if (metadata_size     () > 0) st->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3558                                              p2i(metadata_begin()),
3559                                              p2i(metadata_end()),
3560                                              metadata_size());
3561 #if INCLUDE_JVMCI
3562   if (jvmci_data_size   () > 0) st->print_cr(" JVMCI data     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3563                                              p2i(jvmci_data_begin()),
3564                                              p2i(jvmci_data_end()),
3565                                              jvmci_data_size());
3566 #endif
3567   if (immutable_data_size() > 0) st->print_cr(" immutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3568                                              p2i(immutable_data_begin()),
3569                                              p2i(immutable_data_end()),
3570                                              immutable_data_size());
3571   if (dependencies_size () > 0) st->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3572                                              p2i(dependencies_begin()),
3573                                              p2i(dependencies_end()),
3574                                              dependencies_size());
3575   if (nul_chk_table_size() > 0) st->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3576                                              p2i(nul_chk_table_begin()),
3577                                              p2i(nul_chk_table_end()),
3578                                              nul_chk_table_size());
3579   if (handler_table_size() > 0) st->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3580                                              p2i(handler_table_begin()),
3581                                              p2i(handler_table_end()),
3582                                              handler_table_size());
3583   if (scopes_pcs_size   () > 0) st->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3584                                              p2i(scopes_pcs_begin()),
3585                                              p2i(scopes_pcs_end()),
3586                                              scopes_pcs_size());
3587   if (scopes_data_size  () > 0) st->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3588                                              p2i(scopes_data_begin()),
3589                                              p2i(scopes_data_end()),
3590                                              scopes_data_size());
3591 #if INCLUDE_JVMCI
3592   if (speculations_size () > 0) st->print_cr(" speculations   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3593                                              p2i(speculations_begin()),
3594                                              p2i(speculations_end()),
3595                                              speculations_size());
3596 #endif
3597   if (AOTCodeCache::is_on() && _aot_code_entry != nullptr) {
3598     _aot_code_entry->print(st);
3599   }
3600 }
3601 
3602 void nmethod::print_code() {
3603   ResourceMark m;
3604   ttyLocker ttyl;
3605   // Call the specialized decode method of this class.
3606   decode(tty);
3607 }
3608 
3609 #ifndef PRODUCT  // called InstanceKlass methods are available only then. Declared as PRODUCT_RETURN
3610 
3611 void nmethod::print_dependencies_on(outputStream* out) {
3612   ResourceMark rm;
3613   stringStream st;
3614   st.print_cr("Dependencies:");
3615   for (Dependencies::DepStream deps(this); deps.next(); ) {
3616     deps.print_dependency(&st);
3617     InstanceKlass* ctxk = deps.context_type();
3618     if (ctxk != nullptr) {
3619       if (ctxk->is_dependent_nmethod(this)) {
3620         st.print_cr("   [nmethod<=klass]%s", ctxk->external_name());
3621       }
3622     }
3623     deps.log_dependency();  // put it into the xml log also
3624   }
3625   out->print_raw(st.as_string());
3626 }
3627 #endif
3628 
3629 #if defined(SUPPORT_DATA_STRUCTS)
3630 
3631 // Print the oops from the underlying CodeBlob.
3632 void nmethod::print_oops(outputStream* st) {
3633   ResourceMark m;
3634   st->print("Oops:");
3635   if (oops_begin() < oops_end()) {
3636     st->cr();
3637     for (oop* p = oops_begin(); p < oops_end(); p++) {
3638       Disassembler::print_location((unsigned char*)p, (unsigned char*)oops_begin(), (unsigned char*)oops_end(), st, true, false);
3639       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3640       if (Universe::contains_non_oop_word(p)) {
3641         st->print_cr("NON_OOP");
3642         continue;  // skip non-oops
3643       }
3644       if (*p == nullptr) {
3645         st->print_cr("nullptr-oop");
3646         continue;  // skip non-oops
3647       }
3648       (*p)->print_value_on(st);
3649       st->cr();
3650     }
3651   } else {
3652     st->print_cr(" <list empty>");
3653   }
3654 }
3655 
3656 // Print metadata pool.
3657 void nmethod::print_metadata(outputStream* st) {
3658   ResourceMark m;
3659   st->print("Metadata:");
3660   if (metadata_begin() < metadata_end()) {
3661     st->cr();
3662     for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
3663       Disassembler::print_location((unsigned char*)p, (unsigned char*)metadata_begin(), (unsigned char*)metadata_end(), st, true, false);
3664       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3665       if (*p && *p != Universe::non_oop_word()) {
3666         (*p)->print_value_on(st);
3667       }
3668       st->cr();
3669     }
3670   } else {
3671     st->print_cr(" <list empty>");
3672   }
3673 }
3674 
3675 #ifndef PRODUCT  // ScopeDesc::print_on() is available only then. Declared as PRODUCT_RETURN
3676 void nmethod::print_scopes_on(outputStream* st) {
3677   // Find the first pc desc for all scopes in the code and print it.
3678   ResourceMark rm;
3679   st->print("scopes:");
3680   if (scopes_pcs_begin() < scopes_pcs_end()) {
3681     st->cr();
3682     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3683       if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
3684         continue;
3685 
3686       ScopeDesc* sd = scope_desc_at(p->real_pc(this));
3687       while (sd != nullptr) {
3688         sd->print_on(st, p);  // print output ends with a newline
3689         sd = sd->sender();
3690       }
3691     }
3692   } else {
3693     st->print_cr(" <list empty>");
3694   }
3695 }
3696 #endif
3697 
3698 #ifndef PRODUCT  // RelocIterator does support printing only then.
3699 void nmethod::print_relocations_on(outputStream* st) {
3700   ResourceMark m;       // in case methods get printed via the debugger
3701   st->print_cr("relocations:");
3702   RelocIterator iter(this);
3703   iter.print_on(st);
3704 }
3705 #endif
3706 
3707 void nmethod::print_pcs_on(outputStream* st) {
3708   ResourceMark m;       // in case methods get printed via debugger
3709   st->print("pc-bytecode offsets:");
3710   if (scopes_pcs_begin() < scopes_pcs_end()) {
3711     st->cr();
3712     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3713       p->print_on(st, this);  // print output ends with a newline
3714     }
3715   } else {
3716     st->print_cr(" <list empty>");
3717   }
3718 }
3719 
3720 void nmethod::print_handler_table() {
3721   ExceptionHandlerTable(this).print(code_begin());
3722 }
3723 
3724 void nmethod::print_nul_chk_table() {
3725   ImplicitExceptionTable(this).print(code_begin());
3726 }
3727 
3728 void nmethod::print_recorded_oop(int log_n, int i) {
3729   void* value;
3730 
3731   if (i == 0) {
3732     value = nullptr;
3733   } else {
3734     // Be careful around non-oop words. Don't create an oop
3735     // with that value, or it will assert in verification code.
3736     if (Universe::contains_non_oop_word(oop_addr_at(i))) {
3737       value = Universe::non_oop_word();
3738     } else {
3739       value = oop_at(i);
3740     }
3741   }
3742 
3743   tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(value));
3744 
3745   if (value == Universe::non_oop_word()) {
3746     tty->print("non-oop word");
3747   } else {
3748     if (value == nullptr) {
3749       tty->print("nullptr-oop");
3750     } else {
3751       oop_at(i)->print_value_on(tty);
3752     }
3753   }
3754 
3755   tty->cr();
3756 }
3757 
3758 void nmethod::print_recorded_oops() {
3759   const int n = oops_count();
3760   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3761   tty->print("Recorded oops:");
3762   if (n > 0) {
3763     tty->cr();
3764     for (int i = 0; i < n; i++) {
3765       print_recorded_oop(log_n, i);
3766     }
3767   } else {
3768     tty->print_cr(" <list empty>");
3769   }
3770 }
3771 
3772 void nmethod::print_recorded_metadata() {
3773   const int n = metadata_count();
3774   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3775   tty->print("Recorded metadata:");
3776   if (n > 0) {
3777     tty->cr();
3778     for (int i = 0; i < n; i++) {
3779       Metadata* m = metadata_at(i);
3780       tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(m));
3781       if (m == (Metadata*)Universe::non_oop_word()) {
3782         tty->print("non-metadata word");
3783       } else if (m == nullptr) {
3784         tty->print("nullptr-oop");
3785       } else {
3786         Metadata::print_value_on_maybe_null(tty, m);
3787       }
3788       tty->cr();
3789     }
3790   } else {
3791     tty->print_cr(" <list empty>");
3792   }
3793 }
3794 #endif
3795 
3796 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
3797 
3798 void nmethod::print_constant_pool(outputStream* st) {
3799   //-----------------------------------
3800   //---<  Print the constant pool  >---
3801   //-----------------------------------
3802   int consts_size = this->consts_size();
3803   if ( consts_size > 0 ) {
3804     unsigned char* cstart = this->consts_begin();
3805     unsigned char* cp     = cstart;
3806     unsigned char* cend   = cp + consts_size;
3807     unsigned int   bytes_per_line = 4;
3808     unsigned int   CP_alignment   = 8;
3809     unsigned int   n;
3810 
3811     st->cr();
3812 
3813     //---<  print CP header to make clear what's printed  >---
3814     if( ((uintptr_t)cp&(CP_alignment-1)) == 0 ) {
3815       n = bytes_per_line;
3816       st->print_cr("[Constant Pool]");
3817       Disassembler::print_location(cp, cstart, cend, st, true, true);
3818       Disassembler::print_hexdata(cp, n, st, true);
3819       st->cr();
3820     } else {
3821       n = (int)((uintptr_t)cp & (bytes_per_line-1));
3822       st->print_cr("[Constant Pool (unaligned)]");
3823     }
3824 
3825     //---<  print CP contents, bytes_per_line at a time  >---
3826     while (cp < cend) {
3827       Disassembler::print_location(cp, cstart, cend, st, true, false);
3828       Disassembler::print_hexdata(cp, n, st, false);
3829       cp += n;
3830       n   = bytes_per_line;
3831       st->cr();
3832     }
3833 
3834     //---<  Show potential alignment gap between constant pool and code  >---
3835     cend = code_begin();
3836     if( cp < cend ) {
3837       n = 4;
3838       st->print_cr("[Code entry alignment]");
3839       while (cp < cend) {
3840         Disassembler::print_location(cp, cstart, cend, st, false, false);
3841         cp += n;
3842         st->cr();
3843       }
3844     }
3845   } else {
3846     st->print_cr("[Constant Pool (empty)]");
3847   }
3848   st->cr();
3849 }
3850 
3851 #endif
3852 
3853 // Disassemble this nmethod.
3854 // Print additional debug information, if requested. This could be code
3855 // comments, block comments, profiling counters, etc.
3856 // The undisassembled format is useful no disassembler library is available.
3857 // The resulting hex dump (with markers) can be disassembled later, or on
3858 // another system, when/where a disassembler library is available.
3859 void nmethod::decode2(outputStream* ost) const {
3860 
3861   // Called from frame::back_trace_with_decode without ResourceMark.
3862   ResourceMark rm;
3863 
3864   // Make sure we have a valid stream to print on.
3865   outputStream* st = ost ? ost : tty;
3866 
3867 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) && ! defined(SUPPORT_ASSEMBLY)
3868   const bool use_compressed_format    = true;
3869   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3870                                                                   AbstractDisassembler::show_block_comment());
3871 #else
3872   const bool use_compressed_format    = Disassembler::is_abstract();
3873   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3874                                                                   AbstractDisassembler::show_block_comment());
3875 #endif
3876 
3877   st->cr();
3878   this->print_on(st);
3879   st->cr();
3880 
3881 #if defined(SUPPORT_ASSEMBLY)
3882   //----------------------------------
3883   //---<  Print real disassembly  >---
3884   //----------------------------------
3885   if (! use_compressed_format) {
3886     st->print_cr("[Disassembly]");
3887     Disassembler::decode(const_cast<nmethod*>(this), st);
3888     st->bol();
3889     st->print_cr("[/Disassembly]");
3890     return;
3891   }
3892 #endif
3893 
3894 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3895 
3896   // Compressed undisassembled disassembly format.
3897   // The following status values are defined/supported:
3898   //   = 0 - currently at bol() position, nothing printed yet on current line.
3899   //   = 1 - currently at position after print_location().
3900   //   > 1 - in the midst of printing instruction stream bytes.
3901   int        compressed_format_idx    = 0;
3902   int        code_comment_column      = 0;
3903   const int  instr_maxlen             = Assembler::instr_maxlen();
3904   const uint tabspacing               = 8;
3905   unsigned char* start = this->code_begin();
3906   unsigned char* p     = this->code_begin();
3907   unsigned char* end   = this->code_end();
3908   unsigned char* pss   = p; // start of a code section (used for offsets)
3909 
3910   if ((start == nullptr) || (end == nullptr)) {
3911     st->print_cr("PrintAssembly not possible due to uninitialized section pointers");
3912     return;
3913   }
3914 #endif
3915 
3916 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3917   //---<  plain abstract disassembly, no comments or anything, just section headers  >---
3918   if (use_compressed_format && ! compressed_with_comments) {
3919     const_cast<nmethod*>(this)->print_constant_pool(st);
3920 
3921     st->bol();
3922     st->cr();
3923     st->print_cr("Loading hsdis library failed, undisassembled code is shown in MachCode section");
3924     //---<  Open the output (Marker for post-mortem disassembler)  >---
3925     st->print_cr("[MachCode]");
3926     const char* header = nullptr;
3927     address p0 = p;
3928     while (p < end) {
3929       address pp = p;
3930       while ((p < end) && (header == nullptr)) {
3931         header = nmethod_section_label(p);
3932         pp  = p;
3933         p  += Assembler::instr_len(p);
3934       }
3935       if (pp > p0) {
3936         AbstractDisassembler::decode_range_abstract(p0, pp, start, end, st, Assembler::instr_maxlen());
3937         p0 = pp;
3938         p  = pp;
3939         header = nullptr;
3940       } else if (header != nullptr) {
3941         st->bol();
3942         st->print_cr("%s", header);
3943         header = nullptr;
3944       }
3945     }
3946     //---<  Close the output (Marker for post-mortem disassembler)  >---
3947     st->bol();
3948     st->print_cr("[/MachCode]");
3949     return;
3950   }
3951 #endif
3952 
3953 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3954   //---<  abstract disassembly with comments and section headers merged in  >---
3955   if (compressed_with_comments) {
3956     const_cast<nmethod*>(this)->print_constant_pool(st);
3957 
3958     st->bol();
3959     st->cr();
3960     st->print_cr("Loading hsdis library failed, undisassembled code is shown in MachCode section");
3961     //---<  Open the output (Marker for post-mortem disassembler)  >---
3962     st->print_cr("[MachCode]");
3963     while ((p < end) && (p != nullptr)) {
3964       const int instruction_size_in_bytes = Assembler::instr_len(p);
3965 
3966       //---<  Block comments for nmethod. Interrupts instruction stream, if any.  >---
3967       // Outputs a bol() before and a cr() after, but only if a comment is printed.
3968       // Prints nmethod_section_label as well.
3969       if (AbstractDisassembler::show_block_comment()) {
3970         print_block_comment(st, p);
3971         if (st->position() == 0) {
3972           compressed_format_idx = 0;
3973         }
3974       }
3975 
3976       //---<  New location information after line break  >---
3977       if (compressed_format_idx == 0) {
3978         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
3979         compressed_format_idx = 1;
3980       }
3981 
3982       //---<  Code comment for current instruction. Address range [p..(p+len))  >---
3983       unsigned char* p_end = p + (ssize_t)instruction_size_in_bytes;
3984       S390_ONLY(if (p_end > end) p_end = end;) // avoid getting past the end
3985 
3986       if (AbstractDisassembler::show_comment() && const_cast<nmethod*>(this)->has_code_comment(p, p_end)) {
3987         //---<  interrupt instruction byte stream for code comment  >---
3988         if (compressed_format_idx > 1) {
3989           st->cr();  // interrupt byte stream
3990           st->cr();  // add an empty line
3991           code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
3992         }
3993         const_cast<nmethod*>(this)->print_code_comment_on(st, code_comment_column, p, p_end );
3994         st->bol();
3995         compressed_format_idx = 0;
3996       }
3997 
3998       //---<  New location information after line break  >---
3999       if (compressed_format_idx == 0) {
4000         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
4001         compressed_format_idx = 1;
4002       }
4003 
4004       //---<  Nicely align instructions for readability  >---
4005       if (compressed_format_idx > 1) {
4006         Disassembler::print_delimiter(st);
4007       }
4008 
4009       //---<  Now, finally, print the actual instruction bytes  >---
4010       unsigned char* p0 = p;
4011       p = Disassembler::decode_instruction_abstract(p, st, instruction_size_in_bytes, instr_maxlen);
4012       compressed_format_idx += (int)(p - p0);
4013 
4014       if (Disassembler::start_newline(compressed_format_idx-1)) {
4015         st->cr();
4016         compressed_format_idx = 0;
4017       }
4018     }
4019     //---<  Close the output (Marker for post-mortem disassembler)  >---
4020     st->bol();
4021     st->print_cr("[/MachCode]");
4022     return;
4023   }
4024 #endif
4025 }
4026 
4027 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
4028 
4029 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
4030   RelocIterator iter(this, begin, end);
4031   bool have_one = false;
4032   while (iter.next()) {
4033     have_one = true;
4034     switch (iter.type()) {
4035         case relocInfo::none: {
4036           // Skip it and check next
4037           break;
4038         }
4039         case relocInfo::oop_type: {
4040           // Get a non-resizable resource-allocated stringStream.
4041           // Our callees make use of (nested) ResourceMarks.
4042           stringStream st(NEW_RESOURCE_ARRAY(char, 1024), 1024);
4043           oop_Relocation* r = iter.oop_reloc();
4044           oop obj = r->oop_value();
4045           st.print("oop(");
4046           if (obj == nullptr) st.print("nullptr");
4047           else obj->print_value_on(&st);
4048           st.print(")");
4049           return st.as_string();
4050         }
4051         case relocInfo::metadata_type: {
4052           stringStream st;
4053           metadata_Relocation* r = iter.metadata_reloc();
4054           Metadata* obj = r->metadata_value();
4055           st.print("metadata(");
4056           if (obj == nullptr) st.print("nullptr");
4057           else obj->print_value_on(&st);
4058           st.print(")");
4059           return st.as_string();
4060         }
4061         case relocInfo::runtime_call_type:
4062         case relocInfo::runtime_call_w_cp_type: {
4063           stringStream st;
4064           st.print("runtime_call");
4065           CallRelocation* r = (CallRelocation*)iter.reloc();
4066           address dest = r->destination();
4067           if (StubRoutines::contains(dest)) {
4068             StubCodeDesc* desc = StubCodeDesc::desc_for(dest);
4069             if (desc == nullptr) {
4070               desc = StubCodeDesc::desc_for(dest + frame::pc_return_offset);
4071             }
4072             if (desc != nullptr) {
4073               st.print(" Stub::%s", desc->name());
4074               return st.as_string();
4075             }
4076           }
4077           CodeBlob* cb = CodeCache::find_blob(dest);
4078           if (cb != nullptr) {
4079             st.print(" %s", cb->name());
4080           } else {
4081             ResourceMark rm;
4082             const int buflen = 1024;
4083             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
4084             int offset;
4085             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
4086               st.print(" %s", buf);
4087               if (offset != 0) {
4088                 st.print("+%d", offset);
4089               }
4090             }
4091           }
4092           return st.as_string();
4093         }
4094         case relocInfo::virtual_call_type: {
4095           stringStream st;
4096           st.print_raw("virtual_call");
4097           virtual_call_Relocation* r = iter.virtual_call_reloc();
4098           Method* m = r->method_value();
4099           if (m != nullptr) {
4100             assert(m->is_method(), "");
4101             m->print_short_name(&st);
4102           }
4103           return st.as_string();
4104         }
4105         case relocInfo::opt_virtual_call_type: {
4106           stringStream st;
4107           st.print_raw("optimized virtual_call");
4108           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
4109           Method* m = r->method_value();
4110           if (m != nullptr) {
4111             assert(m->is_method(), "");
4112             m->print_short_name(&st);
4113           }
4114           return st.as_string();
4115         }
4116         case relocInfo::static_call_type: {
4117           stringStream st;
4118           st.print_raw("static_call");
4119           static_call_Relocation* r = iter.static_call_reloc();
4120           Method* m = r->method_value();
4121           if (m != nullptr) {
4122             assert(m->is_method(), "");
4123             m->print_short_name(&st);
4124           }
4125           return st.as_string();
4126         }
4127         case relocInfo::static_stub_type:      return "static_stub";
4128         case relocInfo::external_word_type:    return "external_word";
4129         case relocInfo::internal_word_type:    return "internal_word";
4130         case relocInfo::section_word_type:     return "section_word";
4131         case relocInfo::poll_type:             return "poll";
4132         case relocInfo::poll_return_type:      return "poll_return";
4133         case relocInfo::trampoline_stub_type:  return "trampoline_stub";
4134         case relocInfo::entry_guard_type:      return "entry_guard";
4135         case relocInfo::post_call_nop_type:    return "post_call_nop";
4136         case relocInfo::barrier_type: {
4137           barrier_Relocation* const reloc = iter.barrier_reloc();
4138           stringStream st;
4139           st.print("barrier format=%d", reloc->format());
4140           return st.as_string();
4141         }
4142 
4143         case relocInfo::type_mask:             return "type_bit_mask";
4144 
4145         default: {
4146           stringStream st;
4147           st.print("unknown relocInfo=%d", (int) iter.type());
4148           return st.as_string();
4149         }
4150     }
4151   }
4152   return have_one ? "other" : nullptr;
4153 }
4154 
4155 // Return the last scope in (begin..end]
4156 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
4157   PcDesc* p = pc_desc_near(begin+1);
4158   if (p != nullptr && p->real_pc(this) <= end) {
4159     return new ScopeDesc(this, p);
4160   }
4161   return nullptr;
4162 }
4163 
4164 const char* nmethod::nmethod_section_label(address pos) const {
4165   const char* label = nullptr;
4166   if (pos == code_begin())                                              label = "[Instructions begin]";
4167   if (pos == entry_point())                                             label = "[Entry Point]";
4168   if (pos == verified_entry_point())                                    label = "[Verified Entry Point]";
4169   if (pos == consts_begin() && pos != insts_begin())                    label = "[Constants]";
4170   // Check stub_code before checking exception_handler or deopt_handler.
4171   if (pos == this->stub_begin())                                        label = "[Stub Code]";
4172   if (JVMCI_ONLY(_exception_offset >= 0 &&) pos == exception_begin())          label = "[Exception Handler]";
4173   if (JVMCI_ONLY(_deopt_handler_offset != -1 &&) pos == deopt_handler_begin()) label = "[Deopt Handler Code]";
4174   return label;
4175 }
4176 
4177 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels) const {
4178   if (print_section_labels) {
4179     const char* label = nmethod_section_label(block_begin);
4180     if (label != nullptr) {
4181       stream->bol();
4182       stream->print_cr("%s", label);
4183     }
4184   }
4185 
4186   if (block_begin == entry_point()) {
4187     Method* m = method();
4188     if (m != nullptr) {
4189       stream->print("  # ");
4190       m->print_value_on(stream);
4191       stream->cr();
4192     }
4193     if (m != nullptr && !is_osr_method()) {
4194       ResourceMark rm;
4195       int sizeargs = m->size_of_parameters();
4196       BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
4197       VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
4198       {
4199         int sig_index = 0;
4200         if (!m->is_static())
4201           sig_bt[sig_index++] = T_OBJECT; // 'this'
4202         for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
4203           BasicType t = ss.type();
4204           sig_bt[sig_index++] = t;
4205           if (type2size[t] == 2) {
4206             sig_bt[sig_index++] = T_VOID;
4207           } else {
4208             assert(type2size[t] == 1, "size is 1 or 2");
4209           }
4210         }
4211         assert(sig_index == sizeargs, "");
4212       }
4213       const char* spname = "sp"; // make arch-specific?
4214       SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs);
4215       int stack_slot_offset = this->frame_size() * wordSize;
4216       int tab1 = 14, tab2 = 24;
4217       int sig_index = 0;
4218       int arg_index = (m->is_static() ? 0 : -1);
4219       bool did_old_sp = false;
4220       for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
4221         bool at_this = (arg_index == -1);
4222         bool at_old_sp = false;
4223         BasicType t = (at_this ? T_OBJECT : ss.type());
4224         assert(t == sig_bt[sig_index], "sigs in sync");
4225         if (at_this)
4226           stream->print("  # this: ");
4227         else
4228           stream->print("  # parm%d: ", arg_index);
4229         stream->move_to(tab1);
4230         VMReg fst = regs[sig_index].first();
4231         VMReg snd = regs[sig_index].second();
4232         if (fst->is_reg()) {
4233           stream->print("%s", fst->name());
4234           if (snd->is_valid())  {
4235             stream->print(":%s", snd->name());
4236           }
4237         } else if (fst->is_stack()) {
4238           int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
4239           if (offset == stack_slot_offset)  at_old_sp = true;
4240           stream->print("[%s+0x%x]", spname, offset);
4241         } else {
4242           stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
4243         }
4244         stream->print(" ");
4245         stream->move_to(tab2);
4246         stream->print("= ");
4247         if (at_this) {
4248           m->method_holder()->print_value_on(stream);
4249         } else {
4250           bool did_name = false;
4251           if (!at_this && ss.is_reference()) {
4252             Symbol* name = ss.as_symbol();
4253             name->print_value_on(stream);
4254             did_name = true;
4255           }
4256           if (!did_name)
4257             stream->print("%s", type2name(t));
4258         }
4259         if (at_old_sp) {
4260           stream->print("  (%s of caller)", spname);
4261           did_old_sp = true;
4262         }
4263         stream->cr();
4264         sig_index += type2size[t];
4265         arg_index += 1;
4266         if (!at_this)  ss.next();
4267       }
4268       if (!did_old_sp) {
4269         stream->print("  # ");
4270         stream->move_to(tab1);
4271         stream->print("[%s+0x%x]", spname, stack_slot_offset);
4272         stream->print("  (%s of caller)", spname);
4273         stream->cr();
4274       }
4275     }
4276   }
4277 }
4278 
4279 // Returns whether this nmethod has code comments.
4280 bool nmethod::has_code_comment(address begin, address end) {
4281   // scopes?
4282   ScopeDesc* sd  = scope_desc_in(begin, end);
4283   if (sd != nullptr) return true;
4284 
4285   // relocations?
4286   const char* str = reloc_string_for(begin, end);
4287   if (str != nullptr) return true;
4288 
4289   // implicit exceptions?
4290   int cont_offset = ImplicitExceptionTable(this).continuation_offset((uint)(begin - code_begin()));
4291   if (cont_offset != 0) return true;
4292 
4293   return false;
4294 }
4295 
4296 void nmethod::print_code_comment_on(outputStream* st, int column, address begin, address end) {
4297   ImplicitExceptionTable implicit_table(this);
4298   int pc_offset = (int)(begin - code_begin());
4299   int cont_offset = implicit_table.continuation_offset(pc_offset);
4300   bool oop_map_required = false;
4301   if (cont_offset != 0) {
4302     st->move_to(column, 6, 0);
4303     if (pc_offset == cont_offset) {
4304       st->print("; implicit exception: deoptimizes");
4305       oop_map_required = true;
4306     } else {
4307       st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
4308     }
4309   }
4310 
4311   // Find an oopmap in (begin, end].  We use the odd half-closed
4312   // interval so that oop maps and scope descs which are tied to the
4313   // byte after a call are printed with the call itself.  OopMaps
4314   // associated with implicit exceptions are printed with the implicit
4315   // instruction.
4316   address base = code_begin();
4317   ImmutableOopMapSet* oms = oop_maps();
4318   if (oms != nullptr) {
4319     for (int i = 0, imax = oms->count(); i < imax; i++) {
4320       const ImmutableOopMapPair* pair = oms->pair_at(i);
4321       const ImmutableOopMap* om = pair->get_from(oms);
4322       address pc = base + pair->pc_offset();
4323       if (pc >= begin) {
4324 #if INCLUDE_JVMCI
4325         bool is_implicit_deopt = implicit_table.continuation_offset(pair->pc_offset()) == (uint) pair->pc_offset();
4326 #else
4327         bool is_implicit_deopt = false;
4328 #endif
4329         if (is_implicit_deopt ? pc == begin : pc > begin && pc <= end) {
4330           st->move_to(column, 6, 0);
4331           st->print("; ");
4332           om->print_on(st);
4333           oop_map_required = false;
4334         }
4335       }
4336       if (pc > end) {
4337         break;
4338       }
4339     }
4340   }
4341   assert(!oop_map_required, "missed oopmap");
4342 
4343   Thread* thread = Thread::current();
4344 
4345   // Print any debug info present at this pc.
4346   ScopeDesc* sd  = scope_desc_in(begin, end);
4347   if (sd != nullptr) {
4348     st->move_to(column, 6, 0);
4349     if (sd->bci() == SynchronizationEntryBCI) {
4350       st->print(";*synchronization entry");
4351     } else if (sd->bci() == AfterBci) {
4352       st->print(";* method exit (unlocked if synchronized)");
4353     } else if (sd->bci() == UnwindBci) {
4354       st->print(";* unwind (locked if synchronized)");
4355     } else if (sd->bci() == AfterExceptionBci) {
4356       st->print(";* unwind (unlocked if synchronized)");
4357     } else if (sd->bci() == UnknownBci) {
4358       st->print(";* unknown");
4359     } else if (sd->bci() == InvalidFrameStateBci) {
4360       st->print(";* invalid frame state");
4361     } else {
4362       if (sd->method() == nullptr) {
4363         st->print("method is nullptr");
4364       } else if (sd->method()->is_native()) {
4365         st->print("method is native");
4366       } else {
4367         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
4368         st->print(";*%s", Bytecodes::name(bc));
4369         switch (bc) {
4370         case Bytecodes::_invokevirtual:
4371         case Bytecodes::_invokespecial:
4372         case Bytecodes::_invokestatic:
4373         case Bytecodes::_invokeinterface:
4374           {
4375             Bytecode_invoke invoke(methodHandle(thread, sd->method()), sd->bci());
4376             st->print(" ");
4377             if (invoke.name() != nullptr)
4378               invoke.name()->print_symbol_on(st);
4379             else
4380               st->print("<UNKNOWN>");
4381             break;
4382           }
4383         case Bytecodes::_getfield:
4384         case Bytecodes::_putfield:
4385         case Bytecodes::_getstatic:
4386         case Bytecodes::_putstatic:
4387           {
4388             Bytecode_field field(methodHandle(thread, sd->method()), sd->bci());
4389             st->print(" ");
4390             if (field.name() != nullptr)
4391               field.name()->print_symbol_on(st);
4392             else
4393               st->print("<UNKNOWN>");
4394           }
4395         default:
4396           break;
4397         }
4398       }
4399       st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
4400     }
4401 
4402     // Print all scopes
4403     for (;sd != nullptr; sd = sd->sender()) {
4404       st->move_to(column, 6, 0);
4405       st->print("; -");
4406       if (sd->should_reexecute()) {
4407         st->print(" (reexecute)");
4408       }
4409       if (sd->method() == nullptr) {
4410         st->print("method is nullptr");
4411       } else {
4412         sd->method()->print_short_name(st);
4413       }
4414       int lineno = sd->method()->line_number_from_bci(sd->bci());
4415       if (lineno != -1) {
4416         st->print("@%d (line %d)", sd->bci(), lineno);
4417       } else {
4418         st->print("@%d", sd->bci());
4419       }
4420       st->cr();
4421     }
4422   }
4423 
4424   // Print relocation information
4425   // Prevent memory leak: allocating without ResourceMark.
4426   ResourceMark rm;
4427   const char* str = reloc_string_for(begin, end);
4428   if (str != nullptr) {
4429     if (sd != nullptr) st->cr();
4430     st->move_to(column, 6, 0);
4431     st->print(";   {%s}", str);
4432   }
4433 }
4434 
4435 #endif
4436 
4437 address nmethod::call_instruction_address(address pc) const {
4438   if (NativeCall::is_call_before(pc)) {
4439     NativeCall *ncall = nativeCall_before(pc);
4440     return ncall->instruction_address();
4441   }
4442   return nullptr;
4443 }
4444 
4445 void nmethod::print_value_on_impl(outputStream* st) const {
4446   st->print_cr("nmethod");
4447 #if defined(SUPPORT_DATA_STRUCTS)
4448   print_on_with_msg(st, nullptr);
4449 #endif
4450 }
4451 
4452 #ifndef PRODUCT
4453 
4454 void nmethod::print_calls(outputStream* st) {
4455   RelocIterator iter(this);
4456   while (iter.next()) {
4457     switch (iter.type()) {
4458     case relocInfo::virtual_call_type: {
4459       CompiledICLocker ml_verify(this);
4460       CompiledIC_at(&iter)->print();
4461       break;
4462     }
4463     case relocInfo::static_call_type:
4464     case relocInfo::opt_virtual_call_type:
4465       st->print_cr("Direct call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
4466       CompiledDirectCall::at(iter.reloc())->print();
4467       break;
4468     default:
4469       break;
4470     }
4471   }
4472 }
4473 
4474 void nmethod::print_statistics() {
4475   ttyLocker ttyl;
4476   if (xtty != nullptr)  xtty->head("statistics type='nmethod'");
4477   native_nmethod_stats.print_native_nmethod_stats();
4478 #ifdef COMPILER1
4479   c1_java_nmethod_stats.print_nmethod_stats("C1");
4480 #endif
4481 #ifdef COMPILER2
4482   c2_java_nmethod_stats.print_nmethod_stats("C2");
4483 #endif
4484 #if INCLUDE_JVMCI
4485   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
4486 #endif
4487   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
4488   DebugInformationRecorder::print_statistics();
4489   pc_nmethod_stats.print_pc_stats();
4490   Dependencies::print_statistics();
4491   ExternalsRecorder::print_statistics();
4492   if (xtty != nullptr)  xtty->tail("statistics");
4493 }
4494 
4495 #endif // !PRODUCT
4496 
4497 #if INCLUDE_JVMCI
4498 void nmethod::update_speculation(JavaThread* thread) {
4499   jlong speculation = thread->pending_failed_speculation();
4500   if (speculation != 0) {
4501     guarantee(jvmci_nmethod_data() != nullptr, "failed speculation in nmethod without failed speculation list");
4502     jvmci_nmethod_data()->add_failed_speculation(this, speculation);
4503     thread->set_pending_failed_speculation(0);
4504   }
4505 }
4506 
4507 const char* nmethod::jvmci_name() {
4508   if (jvmci_nmethod_data() != nullptr) {
4509     return jvmci_nmethod_data()->name();
4510   }
4511   return nullptr;
4512 }
4513 
4514 bool nmethod::jvmci_skip_profile_deopt() const {
4515   return jvmci_nmethod_data() != nullptr && !jvmci_nmethod_data()->profile_deopt();
4516 }
4517 #endif
4518 
4519 void nmethod::prepare_for_archiving_impl() {
4520   CodeBlob::prepare_for_archiving_impl();
4521   _deoptimization_generation = 0;
4522   _gc_epoch = 0;
4523   _method_profiling_count = 0;
4524   _osr_link = nullptr;
4525   _method = nullptr;
4526   _immutable_data = nullptr;
4527   _pc_desc_container = nullptr;
4528   _exception_cache = nullptr;
4529   _gc_data = nullptr;
4530   _oops_do_mark_link = nullptr;
4531   _compiled_ic_data = nullptr;
4532   _osr_entry_point = nullptr;
4533   _compile_id = -1;
4534   _deoptimization_status = not_marked;
4535   _is_unloading_state = 0;
4536   _state = not_installed;
4537 }