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/codeCache.hpp"
  27 #include "code/compiledIC.hpp"
  28 #include "code/dependencies.hpp"
  29 #include "code/nativeInst.hpp"
  30 #include "code/nmethod.inline.hpp"
  31 #include "code/scopeDesc.hpp"
  32 #include "compiler/abstractCompiler.hpp"
  33 #include "compiler/compilationLog.hpp"
  34 #include "compiler/compileBroker.hpp"
  35 #include "compiler/compileLog.hpp"
  36 #include "compiler/compileTask.hpp"
  37 #include "compiler/compilerDirectives.hpp"
  38 #include "compiler/compilerOracle.hpp"
  39 #include "compiler/directivesParser.hpp"
  40 #include "compiler/disassembler.hpp"
  41 #include "compiler/oopMap.inline.hpp"
  42 #include "gc/shared/barrierSet.hpp"
  43 #include "gc/shared/barrierSetNMethod.hpp"
  44 #include "gc/shared/classUnloadingContext.hpp"
  45 #include "gc/shared/collectedHeap.hpp"
  46 #include "interpreter/bytecode.inline.hpp"
  47 #include "jvm.h"
  48 #include "logging/log.hpp"
  49 #include "logging/logStream.hpp"
  50 #include "memory/allocation.inline.hpp"
  51 #include "memory/resourceArea.hpp"
  52 #include "memory/universe.hpp"
  53 #include "oops/access.inline.hpp"
  54 #include "oops/klass.inline.hpp"
  55 #include "oops/method.inline.hpp"
  56 #include "oops/methodData.hpp"
  57 #include "oops/oop.inline.hpp"
  58 #include "oops/weakHandle.inline.hpp"
  59 #include "prims/jvmtiImpl.hpp"
  60 #include "prims/jvmtiThreadState.hpp"
  61 #include "prims/methodHandles.hpp"
  62 #include "runtime/continuation.hpp"
  63 #include "runtime/atomic.hpp"
  64 #include "runtime/deoptimization.hpp"
  65 #include "runtime/flags/flagSetting.hpp"
  66 #include "runtime/frame.inline.hpp"
  67 #include "runtime/handles.inline.hpp"
  68 #include "runtime/jniHandles.inline.hpp"
  69 #include "runtime/orderAccess.hpp"
  70 #include "runtime/os.hpp"
  71 #include "runtime/safepointVerifiers.hpp"
  72 #include "runtime/serviceThread.hpp"
  73 #include "runtime/sharedRuntime.hpp"
  74 #include "runtime/signature.hpp"
  75 #include "runtime/threadWXSetters.inline.hpp"
  76 #include "runtime/vmThread.hpp"
  77 #include "utilities/align.hpp"
  78 #include "utilities/copy.hpp"
  79 #include "utilities/dtrace.hpp"
  80 #include "utilities/events.hpp"
  81 #include "utilities/globalDefinitions.hpp"
  82 #include "utilities/resourceHash.hpp"
  83 #include "utilities/xmlstream.hpp"
  84 #if INCLUDE_JVMCI
  85 #include "jvmci/jvmciRuntime.hpp"
  86 #endif
  87 
  88 #ifdef DTRACE_ENABLED
  89 
  90 // Only bother with this argument setup if dtrace is available
  91 
  92 #define DTRACE_METHOD_UNLOAD_PROBE(method)                                \
  93   {                                                                       \
  94     Method* m = (method);                                                 \
  95     if (m != nullptr) {                                                   \
  96       Symbol* klass_name = m->klass_name();                               \
  97       Symbol* name = m->name();                                           \
  98       Symbol* signature = m->signature();                                 \
  99       HOTSPOT_COMPILED_METHOD_UNLOAD(                                     \
 100         (char *) klass_name->bytes(), klass_name->utf8_length(),          \
 101         (char *) name->bytes(), name->utf8_length(),                      \
 102         (char *) signature->bytes(), signature->utf8_length());           \
 103     }                                                                     \
 104   }
 105 
 106 #else //  ndef DTRACE_ENABLED
 107 
 108 #define DTRACE_METHOD_UNLOAD_PROBE(method)
 109 
 110 #endif
 111 
 112 // Cast from int value to narrow type
 113 #define CHECKED_CAST(result, T, thing)      \
 114   result = static_cast<T>(thing); \
 115   assert(static_cast<int>(result) == thing, "failed: %d != %d", static_cast<int>(result), thing);
 116 
 117 //---------------------------------------------------------------------------------
 118 // NMethod statistics
 119 // They are printed under various flags, including:
 120 //   PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
 121 // (In the latter two cases, they like other stats are printed to the log only.)
 122 
 123 #ifndef PRODUCT
 124 // These variables are put into one block to reduce relocations
 125 // and make it simpler to print from the debugger.
 126 struct java_nmethod_stats_struct {
 127   uint nmethod_count;
 128   uint total_nm_size;
 129   uint total_immut_size;
 130   uint total_mut_size;
 131   uint relocation_size;
 132   uint consts_size;
 133   uint insts_size;
 134   uint stub_size;
 135   uint oops_size;
 136   uint metadata_size;
 137   uint dependencies_size;
 138   uint nul_chk_table_size;
 139   uint handler_table_size;
 140   uint scopes_pcs_size;
 141   uint scopes_data_size;
 142 #if INCLUDE_JVMCI
 143   uint speculations_size;
 144   uint jvmci_data_size;
 145 #endif
 146 
 147   void note_nmethod(nmethod* nm) {
 148     nmethod_count += 1;
 149     total_nm_size       += nm->size();
 150     total_immut_size    += nm->immutable_data_size();
 151     total_mut_size      += nm->mutable_data_size();
 152     relocation_size     += nm->relocation_size();
 153     consts_size         += nm->consts_size();
 154     insts_size          += nm->insts_size();
 155     stub_size           += nm->stub_size();
 156     oops_size           += nm->oops_size();
 157     metadata_size       += nm->metadata_size();
 158     scopes_data_size    += nm->scopes_data_size();
 159     scopes_pcs_size     += nm->scopes_pcs_size();
 160     dependencies_size   += nm->dependencies_size();
 161     handler_table_size  += nm->handler_table_size();
 162     nul_chk_table_size  += nm->nul_chk_table_size();
 163 #if INCLUDE_JVMCI
 164     speculations_size   += nm->speculations_size();
 165     jvmci_data_size     += nm->jvmci_data_size();
 166 #endif
 167   }
 168   void print_nmethod_stats(const char* name) {
 169     if (nmethod_count == 0)  return;
 170     tty->print_cr("Statistics for %u bytecoded nmethods for %s:", nmethod_count, name);
 171     uint total_size = total_nm_size + total_immut_size + total_mut_size;
 172     if (total_nm_size != 0) {
 173       tty->print_cr(" total size      = %u (100%%)", total_size);
 174       tty->print_cr(" in CodeCache    = %u (%f%%)", total_nm_size, (total_nm_size * 100.0f)/total_size);
 175     }
 176     uint header_size = (uint)(nmethod_count * sizeof(nmethod));
 177     if (nmethod_count != 0) {
 178       tty->print_cr("   header        = %u (%f%%)", header_size, (header_size * 100.0f)/total_nm_size);
 179     }
 180     if (consts_size != 0) {
 181       tty->print_cr("   constants     = %u (%f%%)", consts_size, (consts_size * 100.0f)/total_nm_size);
 182     }
 183     if (insts_size != 0) {
 184       tty->print_cr("   main code     = %u (%f%%)", insts_size, (insts_size * 100.0f)/total_nm_size);
 185     }
 186     if (stub_size != 0) {
 187       tty->print_cr("   stub code     = %u (%f%%)", stub_size, (stub_size * 100.0f)/total_nm_size);
 188     }
 189     if (oops_size != 0) {
 190       tty->print_cr("   oops          = %u (%f%%)", oops_size, (oops_size * 100.0f)/total_nm_size);
 191     }
 192     if (total_mut_size != 0) {
 193       tty->print_cr(" mutable data    = %u (%f%%)", total_mut_size, (total_mut_size * 100.0f)/total_size);
 194     }
 195     if (relocation_size != 0) {
 196       tty->print_cr("   relocation    = %u (%f%%)", relocation_size, (relocation_size * 100.0f)/total_mut_size);
 197     }
 198     if (metadata_size != 0) {
 199       tty->print_cr("   metadata      = %u (%f%%)", metadata_size, (metadata_size * 100.0f)/total_mut_size);
 200     }
 201 #if INCLUDE_JVMCI
 202     if (jvmci_data_size != 0) {
 203       tty->print_cr("   JVMCI data    = %u (%f%%)", jvmci_data_size, (jvmci_data_size * 100.0f)/total_mut_size);
 204     }
 205 #endif
 206     if (total_immut_size != 0) {
 207       tty->print_cr(" immutable data  = %u (%f%%)", total_immut_size, (total_immut_size * 100.0f)/total_size);
 208     }
 209     if (dependencies_size != 0) {
 210       tty->print_cr("   dependencies  = %u (%f%%)", dependencies_size, (dependencies_size * 100.0f)/total_immut_size);
 211     }
 212     if (nul_chk_table_size != 0) {
 213       tty->print_cr("   nul chk table = %u (%f%%)", nul_chk_table_size, (nul_chk_table_size * 100.0f)/total_immut_size);
 214     }
 215     if (handler_table_size != 0) {
 216       tty->print_cr("   handler table = %u (%f%%)", handler_table_size, (handler_table_size * 100.0f)/total_immut_size);
 217     }
 218     if (scopes_pcs_size != 0) {
 219       tty->print_cr("   scopes pcs    = %u (%f%%)", scopes_pcs_size, (scopes_pcs_size * 100.0f)/total_immut_size);
 220     }
 221     if (scopes_data_size != 0) {
 222       tty->print_cr("   scopes data   = %u (%f%%)", scopes_data_size, (scopes_data_size * 100.0f)/total_immut_size);
 223     }
 224 #if INCLUDE_JVMCI
 225     if (speculations_size != 0) {
 226       tty->print_cr("   speculations  = %u (%f%%)", speculations_size, (speculations_size * 100.0f)/total_immut_size);
 227     }
 228 #endif
 229   }
 230 };
 231 
 232 struct native_nmethod_stats_struct {
 233   uint native_nmethod_count;
 234   uint native_total_size;
 235   uint native_relocation_size;
 236   uint native_insts_size;
 237   uint native_oops_size;
 238   uint native_metadata_size;
 239   void note_native_nmethod(nmethod* nm) {
 240     native_nmethod_count += 1;
 241     native_total_size       += nm->size();
 242     native_relocation_size  += nm->relocation_size();
 243     native_insts_size       += nm->insts_size();
 244     native_oops_size        += nm->oops_size();
 245     native_metadata_size    += nm->metadata_size();
 246   }
 247   void print_native_nmethod_stats() {
 248     if (native_nmethod_count == 0)  return;
 249     tty->print_cr("Statistics for %u native nmethods:", native_nmethod_count);
 250     if (native_total_size != 0)       tty->print_cr(" N. total size  = %u", native_total_size);
 251     if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %u", native_relocation_size);
 252     if (native_insts_size != 0)       tty->print_cr(" N. main code   = %u", native_insts_size);
 253     if (native_oops_size != 0)        tty->print_cr(" N. oops        = %u", native_oops_size);
 254     if (native_metadata_size != 0)    tty->print_cr(" N. metadata    = %u", native_metadata_size);
 255   }
 256 };
 257 
 258 struct pc_nmethod_stats_struct {
 259   uint pc_desc_init;     // number of initialization of cache (= number of caches)
 260   uint pc_desc_queries;  // queries to nmethod::find_pc_desc
 261   uint pc_desc_approx;   // number of those which have approximate true
 262   uint pc_desc_repeats;  // number of _pc_descs[0] hits
 263   uint pc_desc_hits;     // number of LRU cache hits
 264   uint pc_desc_tests;    // total number of PcDesc examinations
 265   uint pc_desc_searches; // total number of quasi-binary search steps
 266   uint pc_desc_adds;     // number of LUR cache insertions
 267 
 268   void print_pc_stats() {
 269     tty->print_cr("PcDesc Statistics:  %u queries, %.2f comparisons per query",
 270                   pc_desc_queries,
 271                   (double)(pc_desc_tests + pc_desc_searches)
 272                   / pc_desc_queries);
 273     tty->print_cr("  caches=%d queries=%u/%u, hits=%u+%u, tests=%u+%u, adds=%u",
 274                   pc_desc_init,
 275                   pc_desc_queries, pc_desc_approx,
 276                   pc_desc_repeats, pc_desc_hits,
 277                   pc_desc_tests, pc_desc_searches, pc_desc_adds);
 278   }
 279 };
 280 
 281 #ifdef COMPILER1
 282 static java_nmethod_stats_struct c1_java_nmethod_stats;
 283 #endif
 284 #ifdef COMPILER2
 285 static java_nmethod_stats_struct c2_java_nmethod_stats;
 286 #endif
 287 #if INCLUDE_JVMCI
 288 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
 289 #endif
 290 static java_nmethod_stats_struct unknown_java_nmethod_stats;
 291 
 292 static native_nmethod_stats_struct native_nmethod_stats;
 293 static pc_nmethod_stats_struct pc_nmethod_stats;
 294 
 295 static void note_java_nmethod(nmethod* nm) {
 296 #ifdef COMPILER1
 297   if (nm->is_compiled_by_c1()) {
 298     c1_java_nmethod_stats.note_nmethod(nm);
 299   } else
 300 #endif
 301 #ifdef COMPILER2
 302   if (nm->is_compiled_by_c2()) {
 303     c2_java_nmethod_stats.note_nmethod(nm);
 304   } else
 305 #endif
 306 #if INCLUDE_JVMCI
 307   if (nm->is_compiled_by_jvmci()) {
 308     jvmci_java_nmethod_stats.note_nmethod(nm);
 309   } else
 310 #endif
 311   {
 312     unknown_java_nmethod_stats.note_nmethod(nm);
 313   }
 314 }
 315 #endif // !PRODUCT
 316 
 317 //---------------------------------------------------------------------------------
 318 
 319 
 320 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
 321   assert(pc != nullptr, "Must be non null");
 322   assert(exception.not_null(), "Must be non null");
 323   assert(handler != nullptr, "Must be non null");
 324 
 325   _count = 0;
 326   _exception_type = exception->klass();
 327   _next = nullptr;
 328   _purge_list_next = nullptr;
 329 
 330   add_address_and_handler(pc,handler);
 331 }
 332 
 333 
 334 address ExceptionCache::match(Handle exception, address pc) {
 335   assert(pc != nullptr,"Must be non null");
 336   assert(exception.not_null(),"Must be non null");
 337   if (exception->klass() == exception_type()) {
 338     return (test_address(pc));
 339   }
 340 
 341   return nullptr;
 342 }
 343 
 344 
 345 bool ExceptionCache::match_exception_with_space(Handle exception) {
 346   assert(exception.not_null(),"Must be non null");
 347   if (exception->klass() == exception_type() && count() < cache_size) {
 348     return true;
 349   }
 350   return false;
 351 }
 352 
 353 
 354 address ExceptionCache::test_address(address addr) {
 355   int limit = count();
 356   for (int i = 0; i < limit; i++) {
 357     if (pc_at(i) == addr) {
 358       return handler_at(i);
 359     }
 360   }
 361   return nullptr;
 362 }
 363 
 364 
 365 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
 366   if (test_address(addr) == handler) return true;
 367 
 368   int index = count();
 369   if (index < cache_size) {
 370     set_pc_at(index, addr);
 371     set_handler_at(index, handler);
 372     increment_count();
 373     return true;
 374   }
 375   return false;
 376 }
 377 
 378 ExceptionCache* ExceptionCache::next() {
 379   return Atomic::load(&_next);
 380 }
 381 
 382 void ExceptionCache::set_next(ExceptionCache *ec) {
 383   Atomic::store(&_next, ec);
 384 }
 385 
 386 //-----------------------------------------------------------------------------
 387 
 388 
 389 // Helper used by both find_pc_desc methods.
 390 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
 391   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
 392   if (!approximate) {
 393     return pc->pc_offset() == pc_offset;
 394   } else {
 395     return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
 396   }
 397 }
 398 
 399 void PcDescCache::init_to(PcDesc* initial_pc_desc) {
 400   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_init);
 401   // initialize the cache by filling it with benign (non-null) values
 402   assert(initial_pc_desc != nullptr && initial_pc_desc->pc_offset() == PcDesc::lower_offset_limit,
 403          "must start with a sentinel");
 404   for (int i = 0; i < cache_size; i++) {
 405     _pc_descs[i] = initial_pc_desc;
 406   }
 407 }
 408 
 409 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
 410   // Note: one might think that caching the most recently
 411   // read value separately would be a win, but one would be
 412   // wrong.  When many threads are updating it, the cache
 413   // line it's in would bounce between caches, negating
 414   // any benefit.
 415 
 416   // In order to prevent race conditions do not load cache elements
 417   // repeatedly, but use a local copy:
 418   PcDesc* res;
 419 
 420   // Step one:  Check the most recently added value.
 421   res = _pc_descs[0];
 422   assert(res != nullptr, "PcDesc cache should be initialized already");
 423 
 424   // Approximate only here since PcDescContainer::find_pc_desc() checked for exact case.
 425   if (approximate && match_desc(res, pc_offset, approximate)) {
 426     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
 427     return res;
 428   }
 429 
 430   // Step two:  Check the rest of the LRU cache.
 431   for (int i = 1; i < cache_size; ++i) {
 432     res = _pc_descs[i];
 433     if (res->pc_offset() < 0) break;  // optimization: skip empty cache
 434     if (match_desc(res, pc_offset, approximate)) {
 435       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
 436       return res;
 437     }
 438   }
 439 
 440   // Report failure.
 441   return nullptr;
 442 }
 443 
 444 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
 445   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
 446   // Update the LRU cache by shifting pc_desc forward.
 447   for (int i = 0; i < cache_size; i++)  {
 448     PcDesc* next = _pc_descs[i];
 449     _pc_descs[i] = pc_desc;
 450     pc_desc = next;
 451   }
 452 }
 453 
 454 // adjust pcs_size so that it is a multiple of both oopSize and
 455 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
 456 // of oopSize, then 2*sizeof(PcDesc) is)
 457 static int adjust_pcs_size(int pcs_size) {
 458   int nsize = align_up(pcs_size,   oopSize);
 459   if ((nsize % sizeof(PcDesc)) != 0) {
 460     nsize = pcs_size + sizeof(PcDesc);
 461   }
 462   assert((nsize % oopSize) == 0, "correct alignment");
 463   return nsize;
 464 }
 465 
 466 bool nmethod::is_method_handle_return(address return_pc) {
 467   if (!has_method_handle_invokes())  return false;
 468   PcDesc* pd = pc_desc_at(return_pc);
 469   if (pd == nullptr)
 470     return false;
 471   return pd->is_method_handle_invoke();
 472 }
 473 
 474 // Returns a string version of the method state.
 475 const char* nmethod::state() const {
 476   int state = get_state();
 477   switch (state) {
 478   case not_installed:
 479     return "not installed";
 480   case in_use:
 481     return "in use";
 482   case not_entrant:
 483     return "not_entrant";
 484   default:
 485     fatal("unexpected method state: %d", state);
 486     return nullptr;
 487   }
 488 }
 489 
 490 void nmethod::set_deoptimized_done() {
 491   ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
 492   if (_deoptimization_status != deoptimize_done) { // can't go backwards
 493     Atomic::store(&_deoptimization_status, deoptimize_done);
 494   }
 495 }
 496 
 497 ExceptionCache* nmethod::exception_cache_acquire() const {
 498   return Atomic::load_acquire(&_exception_cache);
 499 }
 500 
 501 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
 502   assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
 503   assert(new_entry != nullptr,"Must be non null");
 504   assert(new_entry->next() == nullptr, "Must be null");
 505 
 506   for (;;) {
 507     ExceptionCache *ec = exception_cache();
 508     if (ec != nullptr) {
 509       Klass* ex_klass = ec->exception_type();
 510       if (!ex_klass->is_loader_alive()) {
 511         // We must guarantee that entries are not inserted with new next pointer
 512         // edges to ExceptionCache entries with dead klasses, due to bad interactions
 513         // with concurrent ExceptionCache cleanup. Therefore, the inserts roll
 514         // the head pointer forward to the first live ExceptionCache, so that the new
 515         // next pointers always point at live ExceptionCaches, that are not removed due
 516         // to concurrent ExceptionCache cleanup.
 517         ExceptionCache* next = ec->next();
 518         if (Atomic::cmpxchg(&_exception_cache, ec, next) == ec) {
 519           CodeCache::release_exception_cache(ec);
 520         }
 521         continue;
 522       }
 523       ec = exception_cache();
 524       if (ec != nullptr) {
 525         new_entry->set_next(ec);
 526       }
 527     }
 528     if (Atomic::cmpxchg(&_exception_cache, ec, new_entry) == ec) {
 529       return;
 530     }
 531   }
 532 }
 533 
 534 void nmethod::clean_exception_cache() {
 535   // For each nmethod, only a single thread may call this cleanup function
 536   // at the same time, whether called in STW cleanup or concurrent cleanup.
 537   // Note that if the GC is processing exception cache cleaning in a concurrent phase,
 538   // then a single writer may contend with cleaning up the head pointer to the
 539   // first ExceptionCache node that has a Klass* that is alive. That is fine,
 540   // as long as there is no concurrent cleanup of next pointers from concurrent writers.
 541   // And the concurrent writers do not clean up next pointers, only the head.
 542   // Also note that concurrent readers will walk through Klass* pointers that are not
 543   // alive. That does not cause ABA problems, because Klass* is deleted after
 544   // a handshake with all threads, after all stale ExceptionCaches have been
 545   // unlinked. That is also when the CodeCache::exception_cache_purge_list()
 546   // is deleted, with all ExceptionCache entries that were cleaned concurrently.
 547   // That similarly implies that CAS operations on ExceptionCache entries do not
 548   // suffer from ABA problems as unlinking and deletion is separated by a global
 549   // handshake operation.
 550   ExceptionCache* prev = nullptr;
 551   ExceptionCache* curr = exception_cache_acquire();
 552 
 553   while (curr != nullptr) {
 554     ExceptionCache* next = curr->next();
 555 
 556     if (!curr->exception_type()->is_loader_alive()) {
 557       if (prev == nullptr) {
 558         // Try to clean head; this is contended by concurrent inserts, that
 559         // both lazily clean the head, and insert entries at the head. If
 560         // the CAS fails, the operation is restarted.
 561         if (Atomic::cmpxchg(&_exception_cache, curr, next) != curr) {
 562           prev = nullptr;
 563           curr = exception_cache_acquire();
 564           continue;
 565         }
 566       } else {
 567         // It is impossible to during cleanup connect the next pointer to
 568         // an ExceptionCache that has not been published before a safepoint
 569         // prior to the cleanup. Therefore, release is not required.
 570         prev->set_next(next);
 571       }
 572       // prev stays the same.
 573 
 574       CodeCache::release_exception_cache(curr);
 575     } else {
 576       prev = curr;
 577     }
 578 
 579     curr = next;
 580   }
 581 }
 582 
 583 // public method for accessing the exception cache
 584 // These are the public access methods.
 585 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
 586   // We never grab a lock to read the exception cache, so we may
 587   // have false negatives. This is okay, as it can only happen during
 588   // the first few exception lookups for a given nmethod.
 589   ExceptionCache* ec = exception_cache_acquire();
 590   while (ec != nullptr) {
 591     address ret_val;
 592     if ((ret_val = ec->match(exception,pc)) != nullptr) {
 593       return ret_val;
 594     }
 595     ec = ec->next();
 596   }
 597   return nullptr;
 598 }
 599 
 600 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
 601   // There are potential race conditions during exception cache updates, so we
 602   // must own the ExceptionCache_lock before doing ANY modifications. Because
 603   // we don't lock during reads, it is possible to have several threads attempt
 604   // to update the cache with the same data. We need to check for already inserted
 605   // copies of the current data before adding it.
 606 
 607   MutexLocker ml(ExceptionCache_lock);
 608   ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
 609 
 610   if (target_entry == nullptr || !target_entry->add_address_and_handler(pc,handler)) {
 611     target_entry = new ExceptionCache(exception,pc,handler);
 612     add_exception_cache_entry(target_entry);
 613   }
 614 }
 615 
 616 // private method for handling exception cache
 617 // These methods are private, and used to manipulate the exception cache
 618 // directly.
 619 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
 620   ExceptionCache* ec = exception_cache_acquire();
 621   while (ec != nullptr) {
 622     if (ec->match_exception_with_space(exception)) {
 623       return ec;
 624     }
 625     ec = ec->next();
 626   }
 627   return nullptr;
 628 }
 629 
 630 bool nmethod::is_at_poll_return(address pc) {
 631   RelocIterator iter(this, pc, pc+1);
 632   while (iter.next()) {
 633     if (iter.type() == relocInfo::poll_return_type)
 634       return true;
 635   }
 636   return false;
 637 }
 638 
 639 
 640 bool nmethod::is_at_poll_or_poll_return(address pc) {
 641   RelocIterator iter(this, pc, pc+1);
 642   while (iter.next()) {
 643     relocInfo::relocType t = iter.type();
 644     if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
 645       return true;
 646   }
 647   return false;
 648 }
 649 
 650 void nmethod::verify_oop_relocations() {
 651   // Ensure sure that the code matches the current oop values
 652   RelocIterator iter(this, nullptr, nullptr);
 653   while (iter.next()) {
 654     if (iter.type() == relocInfo::oop_type) {
 655       oop_Relocation* reloc = iter.oop_reloc();
 656       if (!reloc->oop_is_immediate()) {
 657         reloc->verify_oop_relocation();
 658       }
 659     }
 660   }
 661 }
 662 
 663 
 664 ScopeDesc* nmethod::scope_desc_at(address pc) {
 665   PcDesc* pd = pc_desc_at(pc);
 666   guarantee(pd != nullptr, "scope must be present");
 667   return new ScopeDesc(this, pd);
 668 }
 669 
 670 ScopeDesc* nmethod::scope_desc_near(address pc) {
 671   PcDesc* pd = pc_desc_near(pc);
 672   guarantee(pd != nullptr, "scope must be present");
 673   return new ScopeDesc(this, pd);
 674 }
 675 
 676 address nmethod::oops_reloc_begin() const {
 677   // If the method is not entrant then a JMP is plastered over the
 678   // first few bytes.  If an oop in the old code was there, that oop
 679   // should not get GC'd.  Skip the first few bytes of oops on
 680   // not-entrant methods.
 681   if (frame_complete_offset() != CodeOffsets::frame_never_safe &&
 682       code_begin() + frame_complete_offset() >
 683       verified_entry_point() + NativeJump::instruction_size)
 684   {
 685     // If we have a frame_complete_offset after the native jump, then there
 686     // is no point trying to look for oops before that. This is a requirement
 687     // for being allowed to scan oops concurrently.
 688     return code_begin() + frame_complete_offset();
 689   }
 690 
 691   address low_boundary = verified_entry_point();
 692   if (!is_in_use()) {
 693     low_boundary += NativeJump::instruction_size;
 694     // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
 695     // This means that the low_boundary is going to be a little too high.
 696     // This shouldn't matter, since oops of non-entrant methods are never used.
 697     // In fact, why are we bothering to look at oops in a non-entrant method??
 698   }
 699   return low_boundary;
 700 }
 701 
 702 // Method that knows how to preserve outgoing arguments at call. This method must be
 703 // called with a frame corresponding to a Java invoke
 704 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
 705   if (method() == nullptr) {
 706     return;
 707   }
 708 
 709   // handle the case of an anchor explicitly set in continuation code that doesn't have a callee
 710   JavaThread* thread = reg_map->thread();
 711   if ((thread->has_last_Java_frame() && fr.sp() == thread->last_Java_sp())
 712       JVMTI_ONLY(|| (method()->is_continuation_enter_intrinsic() && thread->on_monitor_waited_event()))) {
 713     return;
 714   }
 715 
 716   if (!method()->is_native()) {
 717     address pc = fr.pc();
 718     bool has_receiver, has_appendix;
 719     Symbol* signature;
 720 
 721     // The method attached by JIT-compilers should be used, if present.
 722     // Bytecode can be inaccurate in such case.
 723     Method* callee = attached_method_before_pc(pc);
 724     if (callee != nullptr) {
 725       has_receiver = !(callee->access_flags().is_static());
 726       has_appendix = false;
 727       signature    = callee->signature();
 728 
 729       // If inline types are passed as fields, use the extended signature
 730       // which contains the types of all (oop) fields of the inline type.
 731       if (is_compiled_by_c2() && callee->has_scalarized_args()) {
 732         const GrowableArray<SigEntry>* sig = callee->adapter()->get_sig_cc();
 733         assert(sig != nullptr, "sig should never be null");
 734         TempNewSymbol tmp_sig = SigEntry::create_symbol(sig);
 735         has_receiver = false; // The extended signature contains the receiver type
 736         fr.oops_compiled_arguments_do(tmp_sig, has_receiver, has_appendix, reg_map, f);
 737         return;
 738       }
 739     } else {
 740       SimpleScopeDesc ssd(this, pc);
 741 
 742       Bytecode_invoke call(methodHandle(Thread::current(), ssd.method()), ssd.bci());
 743       has_receiver = call.has_receiver();
 744       has_appendix = call.has_appendix();
 745       signature    = call.signature();
 746     }
 747 
 748     fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
 749   } else if (method()->is_continuation_enter_intrinsic()) {
 750     // This method only calls Continuation.enter()
 751     Symbol* signature = vmSymbols::continuationEnter_signature();
 752     fr.oops_compiled_arguments_do(signature, false, false, reg_map, f);
 753   }
 754 }
 755 
 756 Method* nmethod::attached_method(address call_instr) {
 757   assert(code_contains(call_instr), "not part of the nmethod");
 758   RelocIterator iter(this, call_instr, call_instr + 1);
 759   while (iter.next()) {
 760     if (iter.addr() == call_instr) {
 761       switch(iter.type()) {
 762         case relocInfo::static_call_type:      return iter.static_call_reloc()->method_value();
 763         case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
 764         case relocInfo::virtual_call_type:     return iter.virtual_call_reloc()->method_value();
 765         default:                               break;
 766       }
 767     }
 768   }
 769   return nullptr; // not found
 770 }
 771 
 772 Method* nmethod::attached_method_before_pc(address pc) {
 773   if (NativeCall::is_call_before(pc)) {
 774     NativeCall* ncall = nativeCall_before(pc);
 775     return attached_method(ncall->instruction_address());
 776   }
 777   return nullptr; // not a call
 778 }
 779 
 780 void nmethod::clear_inline_caches() {
 781   assert(SafepointSynchronize::is_at_safepoint(), "clearing of IC's only allowed at safepoint");
 782   RelocIterator iter(this);
 783   while (iter.next()) {
 784     iter.reloc()->clear_inline_cache();
 785   }
 786 }
 787 
 788 #ifdef ASSERT
 789 // Check class_loader is alive for this bit of metadata.
 790 class CheckClass : public MetadataClosure {
 791   void do_metadata(Metadata* md) {
 792     Klass* klass = nullptr;
 793     if (md->is_klass()) {
 794       klass = ((Klass*)md);
 795     } else if (md->is_method()) {
 796       klass = ((Method*)md)->method_holder();
 797     } else if (md->is_methodData()) {
 798       klass = ((MethodData*)md)->method()->method_holder();
 799     } else {
 800       md->print();
 801       ShouldNotReachHere();
 802     }
 803     assert(klass->is_loader_alive(), "must be alive");
 804   }
 805 };
 806 #endif // ASSERT
 807 
 808 
 809 static void clean_ic_if_metadata_is_dead(CompiledIC *ic) {
 810   ic->clean_metadata();
 811 }
 812 
 813 // Clean references to unloaded nmethods at addr from this one, which is not unloaded.
 814 template <typename CallsiteT>
 815 static void clean_if_nmethod_is_unloaded(CallsiteT* callsite, nmethod* from,
 816                                          bool clean_all) {
 817   CodeBlob* cb = CodeCache::find_blob(callsite->destination());
 818   if (!cb->is_nmethod()) {
 819     return;
 820   }
 821   nmethod* nm = cb->as_nmethod();
 822   if (clean_all || !nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
 823     callsite->set_to_clean();
 824   }
 825 }
 826 
 827 // Cleans caches in nmethods that point to either classes that are unloaded
 828 // or nmethods that are unloaded.
 829 //
 830 // Can be called either in parallel by G1 currently or after all
 831 // nmethods are unloaded.  Return postponed=true in the parallel case for
 832 // inline caches found that point to nmethods that are not yet visited during
 833 // the do_unloading walk.
 834 void nmethod::unload_nmethod_caches(bool unloading_occurred) {
 835   ResourceMark rm;
 836 
 837   // Exception cache only needs to be called if unloading occurred
 838   if (unloading_occurred) {
 839     clean_exception_cache();
 840   }
 841 
 842   cleanup_inline_caches_impl(unloading_occurred, false);
 843 
 844 #ifdef ASSERT
 845   // Check that the metadata embedded in the nmethod is alive
 846   CheckClass check_class;
 847   metadata_do(&check_class);
 848 #endif
 849 }
 850 
 851 void nmethod::run_nmethod_entry_barrier() {
 852   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
 853   if (bs_nm != nullptr) {
 854     // We want to keep an invariant that nmethods found through iterations of a Thread's
 855     // nmethods found in safepoints have gone through an entry barrier and are not armed.
 856     // By calling this nmethod entry barrier, it plays along and acts
 857     // like any other nmethod found on the stack of a thread (fewer surprises).
 858     nmethod* nm = this;
 859     bool alive = bs_nm->nmethod_entry_barrier(nm);
 860     assert(alive, "should be alive");
 861   }
 862 }
 863 
 864 // Only called by whitebox test
 865 void nmethod::cleanup_inline_caches_whitebox() {
 866   assert_locked_or_safepoint(CodeCache_lock);
 867   CompiledICLocker ic_locker(this);
 868   cleanup_inline_caches_impl(false /* unloading_occurred */, true /* clean_all */);
 869 }
 870 
 871 address* nmethod::orig_pc_addr(const frame* fr) {
 872   return (address*) ((address)fr->unextended_sp() + orig_pc_offset());
 873 }
 874 
 875 // Called to clean up after class unloading for live nmethods
 876 void nmethod::cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all) {
 877   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
 878   ResourceMark rm;
 879 
 880   // Find all calls in an nmethod and clear the ones that point to bad nmethods.
 881   RelocIterator iter(this, oops_reloc_begin());
 882   bool is_in_static_stub = false;
 883   while(iter.next()) {
 884 
 885     switch (iter.type()) {
 886 
 887     case relocInfo::virtual_call_type:
 888       if (unloading_occurred) {
 889         // If class unloading occurred we first clear ICs where the cached metadata
 890         // is referring to an unloaded klass or method.
 891         clean_ic_if_metadata_is_dead(CompiledIC_at(&iter));
 892       }
 893 
 894       clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), this, clean_all);
 895       break;
 896 
 897     case relocInfo::opt_virtual_call_type:
 898     case relocInfo::static_call_type:
 899       clean_if_nmethod_is_unloaded(CompiledDirectCall::at(iter.reloc()), this, clean_all);
 900       break;
 901 
 902     case relocInfo::static_stub_type: {
 903       is_in_static_stub = true;
 904       break;
 905     }
 906 
 907     case relocInfo::metadata_type: {
 908       // Only the metadata relocations contained in static/opt virtual call stubs
 909       // contains the Method* passed to c2i adapters. It is the only metadata
 910       // relocation that needs to be walked, as it is the one metadata relocation
 911       // that violates the invariant that all metadata relocations have an oop
 912       // in the compiled method (due to deferred resolution and code patching).
 913 
 914       // This causes dead metadata to remain in compiled methods that are not
 915       // unloading. Unless these slippery metadata relocations of the static
 916       // stubs are at least cleared, subsequent class redefinition operations
 917       // will access potentially free memory, and JavaThread execution
 918       // concurrent to class unloading may call c2i adapters with dead methods.
 919       if (!is_in_static_stub) {
 920         // The first metadata relocation after a static stub relocation is the
 921         // metadata relocation of the static stub used to pass the Method* to
 922         // c2i adapters.
 923         continue;
 924       }
 925       is_in_static_stub = false;
 926       if (is_unloading()) {
 927         // If the nmethod itself is dying, then it may point at dead metadata.
 928         // Nobody should follow that metadata; it is strictly unsafe.
 929         continue;
 930       }
 931       metadata_Relocation* r = iter.metadata_reloc();
 932       Metadata* md = r->metadata_value();
 933       if (md != nullptr && md->is_method()) {
 934         Method* method = static_cast<Method*>(md);
 935         if (!method->method_holder()->is_loader_alive()) {
 936           Atomic::store(r->metadata_addr(), (Method*)nullptr);
 937 
 938           if (!r->metadata_is_immediate()) {
 939             r->fix_metadata_relocation();
 940           }
 941         }
 942       }
 943       break;
 944     }
 945 
 946     default:
 947       break;
 948     }
 949   }
 950 }
 951 
 952 address nmethod::continuation_for_implicit_exception(address pc, bool for_div0_check) {
 953   // Exception happened outside inline-cache check code => we are inside
 954   // an active nmethod => use cpc to determine a return address
 955   int exception_offset = int(pc - code_begin());
 956   int cont_offset = ImplicitExceptionTable(this).continuation_offset( exception_offset );
 957 #ifdef ASSERT
 958   if (cont_offset == 0) {
 959     Thread* thread = Thread::current();
 960     ResourceMark rm(thread);
 961     CodeBlob* cb = CodeCache::find_blob(pc);
 962     assert(cb != nullptr && cb == this, "");
 963 
 964     // Keep tty output consistent. To avoid ttyLocker, we buffer in stream, and print all at once.
 965     stringStream ss;
 966     ss.print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
 967     print_on(&ss);
 968     method()->print_codes_on(&ss);
 969     print_code_on(&ss);
 970     print_pcs_on(&ss);
 971     tty->print("%s", ss.as_string()); // print all at once
 972   }
 973 #endif
 974   if (cont_offset == 0) {
 975     // Let the normal error handling report the exception
 976     return nullptr;
 977   }
 978   if (cont_offset == exception_offset) {
 979 #if INCLUDE_JVMCI
 980     Deoptimization::DeoptReason deopt_reason = for_div0_check ? Deoptimization::Reason_div0_check : Deoptimization::Reason_null_check;
 981     JavaThread *thread = JavaThread::current();
 982     thread->set_jvmci_implicit_exception_pc(pc);
 983     thread->set_pending_deoptimization(Deoptimization::make_trap_request(deopt_reason,
 984                                                                          Deoptimization::Action_reinterpret));
 985     return (SharedRuntime::deopt_blob()->implicit_exception_uncommon_trap());
 986 #else
 987     ShouldNotReachHere();
 988 #endif
 989   }
 990   return code_begin() + cont_offset;
 991 }
 992 
 993 class HasEvolDependency : public MetadataClosure {
 994   bool _has_evol_dependency;
 995  public:
 996   HasEvolDependency() : _has_evol_dependency(false) {}
 997   void do_metadata(Metadata* md) {
 998     if (md->is_method()) {
 999       Method* method = (Method*)md;
1000       if (method->is_old()) {
1001         _has_evol_dependency = true;
1002       }
1003     }
1004   }
1005   bool has_evol_dependency() const { return _has_evol_dependency; }
1006 };
1007 
1008 bool nmethod::has_evol_metadata() {
1009   // Check the metadata in relocIter and CompiledIC and also deoptimize
1010   // any nmethod that has reference to old methods.
1011   HasEvolDependency check_evol;
1012   metadata_do(&check_evol);
1013   if (check_evol.has_evol_dependency() && log_is_enabled(Debug, redefine, class, nmethod)) {
1014     ResourceMark rm;
1015     log_debug(redefine, class, nmethod)
1016             ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on in nmethod metadata",
1017              _method->method_holder()->external_name(),
1018              _method->name()->as_C_string(),
1019              _method->signature()->as_C_string(),
1020              compile_id());
1021   }
1022   return check_evol.has_evol_dependency();
1023 }
1024 
1025 int nmethod::total_size() const {
1026   return
1027     consts_size()        +
1028     insts_size()         +
1029     stub_size()          +
1030     scopes_data_size()   +
1031     scopes_pcs_size()    +
1032     handler_table_size() +
1033     nul_chk_table_size();
1034 }
1035 
1036 const char* nmethod::compile_kind() const {
1037   if (is_osr_method())     return "osr";
1038   if (method() != nullptr && is_native_method()) {
1039     if (method()->is_continuation_native_intrinsic()) {
1040       return "cnt";
1041     }
1042     return "c2n";
1043   }
1044   return nullptr;
1045 }
1046 
1047 const char* nmethod::compiler_name() const {
1048   return compilertype2name(_compiler_type);
1049 }
1050 
1051 #ifdef ASSERT
1052 class CheckForOopsClosure : public OopClosure {
1053   bool _found_oop = false;
1054  public:
1055   virtual void do_oop(oop* o) { _found_oop = true; }
1056   virtual void do_oop(narrowOop* o) { _found_oop = true; }
1057   bool found_oop() { return _found_oop; }
1058 };
1059 class CheckForMetadataClosure : public MetadataClosure {
1060   bool _found_metadata = false;
1061   Metadata* _ignore = nullptr;
1062  public:
1063   CheckForMetadataClosure(Metadata* ignore) : _ignore(ignore) {}
1064   virtual void do_metadata(Metadata* md) { if (md != _ignore) _found_metadata = true; }
1065   bool found_metadata() { return _found_metadata; }
1066 };
1067 
1068 static void assert_no_oops_or_metadata(nmethod* nm) {
1069   if (nm == nullptr) return;
1070   assert(nm->oop_maps() == nullptr, "expectation");
1071 
1072   CheckForOopsClosure cfo;
1073   nm->oops_do(&cfo);
1074   assert(!cfo.found_oop(), "no oops allowed");
1075 
1076   // We allow an exception for the own Method, but require its class to be permanent.
1077   Method* own_method = nm->method();
1078   CheckForMetadataClosure cfm(/* ignore reference to own Method */ own_method);
1079   nm->metadata_do(&cfm);
1080   assert(!cfm.found_metadata(), "no metadata allowed");
1081 
1082   assert(own_method->method_holder()->class_loader_data()->is_permanent_class_loader_data(),
1083          "Method's class needs to be permanent");
1084 }
1085 #endif
1086 
1087 static int required_mutable_data_size(CodeBuffer* code_buffer,
1088                                       int jvmci_data_size = 0) {
1089   return align_up(code_buffer->total_relocation_size(), oopSize) +
1090          align_up(code_buffer->total_metadata_size(), oopSize) +
1091          align_up(jvmci_data_size, oopSize);
1092 }
1093 
1094 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
1095   int compile_id,
1096   CodeBuffer *code_buffer,
1097   int vep_offset,
1098   int frame_complete,
1099   int frame_size,
1100   ByteSize basic_lock_owner_sp_offset,
1101   ByteSize basic_lock_sp_offset,
1102   OopMapSet* oop_maps,
1103   int exception_handler) {
1104   code_buffer->finalize_oop_references(method);
1105   // create nmethod
1106   nmethod* nm = nullptr;
1107   int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1108   {
1109     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1110 
1111     CodeOffsets offsets;
1112     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
1113     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
1114     if (exception_handler != -1) {
1115       offsets.set_value(CodeOffsets::Exceptions, exception_handler);
1116     }
1117 
1118     int mutable_data_size = required_mutable_data_size(code_buffer);
1119 
1120     // MH intrinsics are dispatch stubs which are compatible with NonNMethod space.
1121     // IsUnloadingBehaviour::is_unloading needs to handle them separately.
1122     bool allow_NonNMethod_space = method->can_be_allocated_in_NonNMethod_space();
1123     nm = new (native_nmethod_size, allow_NonNMethod_space)
1124     nmethod(method(), compiler_none, native_nmethod_size,
1125             compile_id, &offsets,
1126             code_buffer, frame_size,
1127             basic_lock_owner_sp_offset,
1128             basic_lock_sp_offset,
1129             oop_maps, mutable_data_size);
1130     DEBUG_ONLY( if (allow_NonNMethod_space) assert_no_oops_or_metadata(nm); )
1131     NOT_PRODUCT(if (nm != nullptr) native_nmethod_stats.note_native_nmethod(nm));
1132   }
1133 
1134   if (nm != nullptr) {
1135     // verify nmethod
1136     debug_only(nm->verify();) // might block
1137 
1138     nm->log_new_nmethod();
1139   }
1140   return nm;
1141 }
1142 
1143 nmethod* nmethod::new_nmethod(const methodHandle& method,
1144   int compile_id,
1145   int entry_bci,
1146   CodeOffsets* offsets,
1147   int orig_pc_offset,
1148   DebugInformationRecorder* debug_info,
1149   Dependencies* dependencies,
1150   CodeBuffer* code_buffer, int frame_size,
1151   OopMapSet* oop_maps,
1152   ExceptionHandlerTable* handler_table,
1153   ImplicitExceptionTable* nul_chk_table,
1154   AbstractCompiler* compiler,
1155   CompLevel comp_level
1156 #if INCLUDE_JVMCI
1157   , char* speculations,
1158   int speculations_len,
1159   JVMCINMethodData* jvmci_data
1160 #endif
1161 )
1162 {
1163   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1164   code_buffer->finalize_oop_references(method);
1165   // create nmethod
1166   nmethod* nm = nullptr;
1167   int nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1168 
1169   int immutable_data_size =
1170       adjust_pcs_size(debug_info->pcs_size())
1171     + align_up((int)dependencies->size_in_bytes(), oopSize)
1172     + align_up(handler_table->size_in_bytes()    , oopSize)
1173     + align_up(nul_chk_table->size_in_bytes()    , oopSize)
1174 #if INCLUDE_JVMCI
1175     + align_up(speculations_len                  , oopSize)
1176 #endif
1177     + align_up(debug_info->data_size()           , oopSize);
1178 
1179   // First, allocate space for immutable data in C heap.
1180   address immutable_data = nullptr;
1181   if (immutable_data_size > 0) {
1182     immutable_data = (address)os::malloc(immutable_data_size, mtCode);
1183     if (immutable_data == nullptr) {
1184       vm_exit_out_of_memory(immutable_data_size, OOM_MALLOC_ERROR, "nmethod: no space for immutable data");
1185       return nullptr;
1186     }
1187   }
1188 
1189   int mutable_data_size = required_mutable_data_size(code_buffer
1190     JVMCI_ONLY(COMMA (compiler->is_jvmci() ? jvmci_data->size() : 0)));
1191 
1192   {
1193     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1194 
1195     nm = new (nmethod_size, comp_level)
1196     nmethod(method(), compiler->type(), nmethod_size, immutable_data_size, mutable_data_size,
1197             compile_id, entry_bci, immutable_data, offsets, orig_pc_offset,
1198             debug_info, dependencies, code_buffer, frame_size, oop_maps,
1199             handler_table, nul_chk_table, compiler, comp_level
1200 #if INCLUDE_JVMCI
1201             , speculations,
1202             speculations_len,
1203             jvmci_data
1204 #endif
1205             );
1206 
1207     if (nm != nullptr) {
1208       // To make dependency checking during class loading fast, record
1209       // the nmethod dependencies in the classes it is dependent on.
1210       // This allows the dependency checking code to simply walk the
1211       // class hierarchy above the loaded class, checking only nmethods
1212       // which are dependent on those classes.  The slow way is to
1213       // check every nmethod for dependencies which makes it linear in
1214       // the number of methods compiled.  For applications with a lot
1215       // classes the slow way is too slow.
1216       for (Dependencies::DepStream deps(nm); deps.next(); ) {
1217         if (deps.type() == Dependencies::call_site_target_value) {
1218           // CallSite dependencies are managed on per-CallSite instance basis.
1219           oop call_site = deps.argument_oop(0);
1220           MethodHandles::add_dependent_nmethod(call_site, nm);
1221         } else {
1222           InstanceKlass* ik = deps.context_type();
1223           if (ik == nullptr) {
1224             continue;  // ignore things like evol_method
1225           }
1226           // record this nmethod as dependent on this klass
1227           ik->add_dependent_nmethod(nm);
1228         }
1229       }
1230       NOT_PRODUCT(if (nm != nullptr)  note_java_nmethod(nm));
1231     }
1232   }
1233   // Do verification and logging outside CodeCache_lock.
1234   if (nm != nullptr) {
1235     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
1236     DEBUG_ONLY(nm->verify();)
1237     nm->log_new_nmethod();
1238   }
1239   return nm;
1240 }
1241 
1242 // Fill in default values for various fields
1243 void nmethod::init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets) {
1244   // avoid uninitialized fields, even for short time periods
1245   _exception_cache            = nullptr;
1246   _gc_data                    = nullptr;
1247   _oops_do_mark_link          = nullptr;
1248   _compiled_ic_data           = nullptr;
1249 
1250   _is_unloading_state         = 0;
1251   _state                      = not_installed;
1252 
1253   _has_unsafe_access          = 0;
1254   _has_method_handle_invokes  = 0;
1255   _has_wide_vectors           = 0;
1256   _has_monitors               = 0;
1257   _has_scoped_access          = 0;
1258   _has_flushed_dependencies   = 0;
1259   _is_unlinked                = 0;
1260   _load_reported              = 0; // jvmti state
1261 
1262   _deoptimization_status      = not_marked;
1263 
1264   // SECT_CONSTS is first in code buffer so the offset should be 0.
1265   int consts_offset = code_buffer->total_offset_of(code_buffer->consts());
1266   assert(consts_offset == 0, "const_offset: %d", consts_offset);
1267 
1268   _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
1269 
1270   CHECKED_CAST(_entry_offset,              uint16_t, (offsets->value(CodeOffsets::Entry)));
1271   CHECKED_CAST(_verified_entry_offset,     uint16_t, (offsets->value(CodeOffsets::Verified_Entry)));
1272 
1273   _inline_entry_point             = entry_point();
1274   _verified_inline_entry_point    = verified_entry_point();
1275   _verified_inline_ro_entry_point = verified_entry_point();
1276 
1277   _skipped_instructions_size = code_buffer->total_skipped_instructions_size();
1278 }
1279 
1280 // Post initialization
1281 void nmethod::post_init() {
1282   clear_unloading_state();
1283 
1284   finalize_relocations();
1285 
1286   Universe::heap()->register_nmethod(this);
1287   debug_only(Universe::heap()->verify_nmethod(this));
1288 
1289   CodeCache::commit(this);
1290 }
1291 
1292 // For native wrappers
1293 nmethod::nmethod(
1294   Method* method,
1295   CompilerType type,
1296   int nmethod_size,
1297   int compile_id,
1298   CodeOffsets* offsets,
1299   CodeBuffer* code_buffer,
1300   int frame_size,
1301   ByteSize basic_lock_owner_sp_offset,
1302   ByteSize basic_lock_sp_offset,
1303   OopMapSet* oop_maps,
1304   int mutable_data_size)
1305   : CodeBlob("native nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1306              offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, mutable_data_size),
1307   _deoptimization_generation(0),
1308   _gc_epoch(CodeCache::gc_epoch()),
1309   _method(method),
1310   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
1311   _native_basic_lock_sp_offset(basic_lock_sp_offset)
1312 {
1313   {
1314     debug_only(NoSafepointVerifier nsv;)
1315     assert_locked_or_safepoint(CodeCache_lock);
1316     assert(!method->has_scalarized_args(), "scalarized native wrappers not supported yet");
1317     init_defaults(code_buffer, offsets);
1318 
1319     _osr_entry_point         = nullptr;
1320     _pc_desc_container       = nullptr;
1321     _entry_bci               = InvocationEntryBci;
1322     _compile_id              = compile_id;
1323     _comp_level              = CompLevel_none;
1324     _compiler_type           = type;
1325     _orig_pc_offset          = 0;
1326     _num_stack_arg_slots     = 0;
1327 
1328     if (offsets->value(CodeOffsets::Exceptions) != -1) {
1329       // Continuation enter intrinsic
1330       _exception_offset      = code_offset() + offsets->value(CodeOffsets::Exceptions);
1331     } else {
1332       _exception_offset      = 0;
1333     }
1334     // Native wrappers do not have deopt handlers. Make the values
1335     // something that will never match a pc like the nmethod vtable entry
1336     _deopt_handler_offset    = 0;
1337     _deopt_mh_handler_offset = 0;
1338     _unwind_handler_offset   = 0;
1339 
1340     CHECKED_CAST(_oops_size, uint16_t, align_up(code_buffer->total_oop_size(), oopSize));
1341     int metadata_size = align_up(code_buffer->total_metadata_size(), wordSize);
1342     JVMCI_ONLY( _jvmci_data_size = 0; )
1343     assert(_mutable_data_size == _relocation_size + metadata_size,
1344            "wrong mutable data size: %d != %d + %d",
1345            _mutable_data_size, _relocation_size, metadata_size);
1346 
1347     // native wrapper does not have read-only data but we need unique not null address
1348     _immutable_data          = blob_end();
1349     _immutable_data_size     = 0;
1350     _nul_chk_table_offset    = 0;
1351     _handler_table_offset    = 0;
1352     _scopes_pcs_offset       = 0;
1353     _scopes_data_offset      = 0;
1354 #if INCLUDE_JVMCI
1355     _speculations_offset     = 0;
1356 #endif
1357 
1358     code_buffer->copy_code_and_locs_to(this);
1359     code_buffer->copy_values_to(this);
1360 
1361     post_init();
1362   }
1363 
1364   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
1365     ttyLocker ttyl;  // keep the following output all in one block
1366     // This output goes directly to the tty, not the compiler log.
1367     // To enable tools to match it up with the compilation activity,
1368     // be sure to tag this tty output with the compile ID.
1369     if (xtty != nullptr) {
1370       xtty->begin_head("print_native_nmethod");
1371       xtty->method(_method);
1372       xtty->stamp();
1373       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
1374     }
1375     // Print the header part, then print the requested information.
1376     // This is both handled in decode2(), called via print_code() -> decode()
1377     if (PrintNativeNMethods) {
1378       tty->print_cr("-------------------------- Assembly (native nmethod) ---------------------------");
1379       print_code();
1380       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1381 #if defined(SUPPORT_DATA_STRUCTS)
1382       if (AbstractDisassembler::show_structs()) {
1383         if (oop_maps != nullptr) {
1384           tty->print("oop maps:"); // oop_maps->print_on(tty) outputs a cr() at the beginning
1385           oop_maps->print_on(tty);
1386           tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1387         }
1388       }
1389 #endif
1390     } else {
1391       print(); // print the header part only.
1392     }
1393 #if defined(SUPPORT_DATA_STRUCTS)
1394     if (AbstractDisassembler::show_structs()) {
1395       if (PrintRelocations) {
1396         print_relocations();
1397         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1398       }
1399     }
1400 #endif
1401     if (xtty != nullptr) {
1402       xtty->tail("print_native_nmethod");
1403     }
1404   }
1405 }
1406 
1407 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
1408   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
1409 }
1410 
1411 void* nmethod::operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw () {
1412   // Try MethodNonProfiled and MethodProfiled.
1413   void* return_value = CodeCache::allocate(nmethod_size, CodeBlobType::MethodNonProfiled);
1414   if (return_value != nullptr || !allow_NonNMethod_space) return return_value;
1415   // Try NonNMethod or give up.
1416   return CodeCache::allocate(nmethod_size, CodeBlobType::NonNMethod);
1417 }
1418 
1419 // For normal JIT compiled code
1420 nmethod::nmethod(
1421   Method* method,
1422   CompilerType type,
1423   int nmethod_size,
1424   int immutable_data_size,
1425   int mutable_data_size,
1426   int compile_id,
1427   int entry_bci,
1428   address immutable_data,
1429   CodeOffsets* offsets,
1430   int orig_pc_offset,
1431   DebugInformationRecorder* debug_info,
1432   Dependencies* dependencies,
1433   CodeBuffer *code_buffer,
1434   int frame_size,
1435   OopMapSet* oop_maps,
1436   ExceptionHandlerTable* handler_table,
1437   ImplicitExceptionTable* nul_chk_table,
1438   AbstractCompiler* compiler,
1439   CompLevel comp_level
1440 #if INCLUDE_JVMCI
1441   , char* speculations,
1442   int speculations_len,
1443   JVMCINMethodData* jvmci_data
1444 #endif
1445   )
1446   : CodeBlob("nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1447              offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, mutable_data_size),
1448   _deoptimization_generation(0),
1449   _gc_epoch(CodeCache::gc_epoch()),
1450   _method(method),
1451   _osr_link(nullptr)
1452 {
1453   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1454   {
1455     debug_only(NoSafepointVerifier nsv;)
1456     assert_locked_or_safepoint(CodeCache_lock);
1457 
1458     init_defaults(code_buffer, offsets);
1459 
1460     _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
1461     _entry_bci       = entry_bci;
1462     _compile_id      = compile_id;
1463     _comp_level      = comp_level;
1464     _compiler_type   = type;
1465     _orig_pc_offset  = orig_pc_offset;
1466 
1467     _num_stack_arg_slots = entry_bci != InvocationEntryBci ? 0 : _method->constMethod()->num_stack_arg_slots();
1468 
1469     set_ctable_begin(header_begin() + content_offset());
1470 
1471 #if INCLUDE_JVMCI
1472     if (compiler->is_jvmci()) {
1473       // JVMCI might not produce any stub sections
1474       if (offsets->value(CodeOffsets::Exceptions) != -1) {
1475         _exception_offset        = code_offset() + offsets->value(CodeOffsets::Exceptions);
1476       } else {
1477         _exception_offset        = -1;
1478       }
1479       if (offsets->value(CodeOffsets::Deopt) != -1) {
1480         _deopt_handler_offset    = code_offset() + offsets->value(CodeOffsets::Deopt);
1481       } else {
1482         _deopt_handler_offset    = -1;
1483       }
1484       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
1485         _deopt_mh_handler_offset = code_offset() + offsets->value(CodeOffsets::DeoptMH);
1486       } else {
1487         _deopt_mh_handler_offset = -1;
1488       }
1489     } else
1490 #endif
1491     {
1492       // Exception handler and deopt handler are in the stub section
1493       assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
1494       assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
1495 
1496       _exception_offset          = _stub_offset + offsets->value(CodeOffsets::Exceptions);
1497       _deopt_handler_offset      = _stub_offset + offsets->value(CodeOffsets::Deopt);
1498       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
1499         _deopt_mh_handler_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
1500       } else {
1501         _deopt_mh_handler_offset = -1;
1502       }
1503     }
1504     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
1505       // C1 generates UnwindHandler at the end of instructions section.
1506       // Calculate positive offset as distance between the start of stubs section
1507       // (which is also the end of instructions section) and the start of the handler.
1508       int unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
1509       CHECKED_CAST(_unwind_handler_offset, int16_t, (_stub_offset - unwind_handler_offset));
1510     } else {
1511       _unwind_handler_offset = -1;
1512     }
1513 
1514     CHECKED_CAST(_oops_size, uint16_t, align_up(code_buffer->total_oop_size(), oopSize));
1515     uint16_t metadata_size = (uint16_t)align_up(code_buffer->total_metadata_size(), wordSize);
1516     JVMCI_ONLY(CHECKED_CAST(_jvmci_data_size, uint16_t, align_up(compiler->is_jvmci() ? jvmci_data->size() : 0, oopSize)));
1517     int jvmci_data_size = 0 JVMCI_ONLY(+ _jvmci_data_size);
1518     _inline_entry_point             = code_begin() + offsets->value(CodeOffsets::Inline_Entry);
1519     _verified_inline_entry_point    = code_begin() + offsets->value(CodeOffsets::Verified_Inline_Entry);
1520     _verified_inline_ro_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Inline_Entry_RO);
1521     assert(_mutable_data_size == _relocation_size + metadata_size + jvmci_data_size,
1522            "wrong mutable data size: %d != %d + %d + %d",
1523            _mutable_data_size, _relocation_size, metadata_size, jvmci_data_size);
1524     assert(nmethod_size == data_end() - header_begin(), "wrong nmethod size: %d != %d",
1525            nmethod_size, (int)(code_end() - header_begin()));
1526 
1527     _immutable_data_size  = immutable_data_size;
1528     if (immutable_data_size > 0) {
1529       assert(immutable_data != nullptr, "required");
1530       _immutable_data     = immutable_data;
1531     } else {
1532       // We need unique not null address
1533       _immutable_data     = blob_end();
1534     }
1535     CHECKED_CAST(_nul_chk_table_offset, uint16_t, (align_up((int)dependencies->size_in_bytes(), oopSize)));
1536     CHECKED_CAST(_handler_table_offset, uint16_t, (_nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize)));
1537     _scopes_pcs_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
1538     _scopes_data_offset   = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
1539 
1540 #if INCLUDE_JVMCI
1541     _speculations_offset  = _scopes_data_offset   + align_up(debug_info->data_size(), oopSize);
1542     DEBUG_ONLY( int immutable_data_end_offset = _speculations_offset  + align_up(speculations_len, oopSize); )
1543 #else
1544     DEBUG_ONLY( int immutable_data_end_offset = _scopes_data_offset + align_up(debug_info->data_size(), oopSize); )
1545 #endif
1546     assert(immutable_data_end_offset <= immutable_data_size, "wrong read-only data size: %d > %d",
1547            immutable_data_end_offset, immutable_data_size);
1548 
1549     // Copy code and relocation info
1550     code_buffer->copy_code_and_locs_to(this);
1551     // Copy oops and metadata
1552     code_buffer->copy_values_to(this);
1553     dependencies->copy_to(this);
1554     // Copy PcDesc and ScopeDesc data
1555     debug_info->copy_to(this);
1556 
1557     // Create cache after PcDesc data is copied - it will be used to initialize cache
1558     _pc_desc_container = new PcDescContainer(scopes_pcs_begin());
1559 
1560 #if INCLUDE_JVMCI
1561     if (compiler->is_jvmci()) {
1562       // Initialize the JVMCINMethodData object inlined into nm
1563       jvmci_nmethod_data()->copy(jvmci_data);
1564     }
1565 #endif
1566 
1567     // Copy contents of ExceptionHandlerTable to nmethod
1568     handler_table->copy_to(this);
1569     nul_chk_table->copy_to(this);
1570 
1571 #if INCLUDE_JVMCI
1572     // Copy speculations to nmethod
1573     if (speculations_size() != 0) {
1574       memcpy(speculations_begin(), speculations, speculations_len);
1575     }
1576 #endif
1577 
1578     post_init();
1579 
1580     // we use the information of entry points to find out if a method is
1581     // static or non static
1582     assert(compiler->is_c2() || compiler->is_jvmci() ||
1583            _method->is_static() == (entry_point() == verified_entry_point()),
1584            " entry points must be same for static methods and vice versa");
1585   }
1586 }
1587 
1588 // Print a short set of xml attributes to identify this nmethod.  The
1589 // output should be embedded in some other element.
1590 void nmethod::log_identity(xmlStream* log) const {
1591   log->print(" compile_id='%d'", compile_id());
1592   const char* nm_kind = compile_kind();
1593   if (nm_kind != nullptr)  log->print(" compile_kind='%s'", nm_kind);
1594   log->print(" compiler='%s'", compiler_name());
1595   if (TieredCompilation) {
1596     log->print(" level='%d'", comp_level());
1597   }
1598 #if INCLUDE_JVMCI
1599   if (jvmci_nmethod_data() != nullptr) {
1600     const char* jvmci_name = jvmci_nmethod_data()->name();
1601     if (jvmci_name != nullptr) {
1602       log->print(" jvmci_mirror_name='");
1603       log->text("%s", jvmci_name);
1604       log->print("'");
1605     }
1606   }
1607 #endif
1608 }
1609 
1610 
1611 #define LOG_OFFSET(log, name)                    \
1612   if (p2i(name##_end()) - p2i(name##_begin())) \
1613     log->print(" " XSTR(name) "_offset='%zd'"    , \
1614                p2i(name##_begin()) - p2i(this))
1615 
1616 
1617 void nmethod::log_new_nmethod() const {
1618   if (LogCompilation && xtty != nullptr) {
1619     ttyLocker ttyl;
1620     xtty->begin_elem("nmethod");
1621     log_identity(xtty);
1622     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
1623     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
1624 
1625     LOG_OFFSET(xtty, relocation);
1626     LOG_OFFSET(xtty, consts);
1627     LOG_OFFSET(xtty, insts);
1628     LOG_OFFSET(xtty, stub);
1629     LOG_OFFSET(xtty, scopes_data);
1630     LOG_OFFSET(xtty, scopes_pcs);
1631     LOG_OFFSET(xtty, dependencies);
1632     LOG_OFFSET(xtty, handler_table);
1633     LOG_OFFSET(xtty, nul_chk_table);
1634     LOG_OFFSET(xtty, oops);
1635     LOG_OFFSET(xtty, metadata);
1636 
1637     xtty->method(method());
1638     xtty->stamp();
1639     xtty->end_elem();
1640   }
1641 }
1642 
1643 #undef LOG_OFFSET
1644 
1645 
1646 // Print out more verbose output usually for a newly created nmethod.
1647 void nmethod::print_on_with_msg(outputStream* st, const char* msg) const {
1648   if (st != nullptr) {
1649     ttyLocker ttyl;
1650     if (WizardMode) {
1651       CompileTask::print(st, this, msg, /*short_form:*/ true);
1652       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
1653     } else {
1654       CompileTask::print(st, this, msg, /*short_form:*/ false);
1655     }
1656   }
1657 }
1658 
1659 void nmethod::maybe_print_nmethod(const DirectiveSet* directive) {
1660   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
1661   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
1662     print_nmethod(printnmethods);
1663   }
1664 }
1665 
1666 void nmethod::print_nmethod(bool printmethod) {
1667   ttyLocker ttyl;  // keep the following output all in one block
1668   if (xtty != nullptr) {
1669     xtty->begin_head("print_nmethod");
1670     log_identity(xtty);
1671     xtty->stamp();
1672     xtty->end_head();
1673   }
1674   // Print the header part, then print the requested information.
1675   // This is both handled in decode2().
1676   if (printmethod) {
1677     ResourceMark m;
1678     if (is_compiled_by_c1()) {
1679       tty->cr();
1680       tty->print_cr("============================= C1-compiled nmethod ==============================");
1681     }
1682     if (is_compiled_by_jvmci()) {
1683       tty->cr();
1684       tty->print_cr("=========================== JVMCI-compiled nmethod =============================");
1685     }
1686     tty->print_cr("----------------------------------- Assembly -----------------------------------");
1687     decode2(tty);
1688 #if defined(SUPPORT_DATA_STRUCTS)
1689     if (AbstractDisassembler::show_structs()) {
1690       // Print the oops from the underlying CodeBlob as well.
1691       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1692       print_oops(tty);
1693       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1694       print_metadata(tty);
1695       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1696       print_pcs_on(tty);
1697       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1698       if (oop_maps() != nullptr) {
1699         tty->print("oop maps:"); // oop_maps()->print_on(tty) outputs a cr() at the beginning
1700         oop_maps()->print_on(tty);
1701         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1702       }
1703     }
1704 #endif
1705   } else {
1706     print(); // print the header part only.
1707   }
1708 
1709 #if defined(SUPPORT_DATA_STRUCTS)
1710   if (AbstractDisassembler::show_structs()) {
1711     methodHandle mh(Thread::current(), _method);
1712     if (printmethod || PrintDebugInfo || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDebugInfo)) {
1713       print_scopes();
1714       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1715     }
1716     if (printmethod || PrintRelocations || CompilerOracle::has_option(mh, CompileCommandEnum::PrintRelocations)) {
1717       print_relocations();
1718       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1719     }
1720     if (printmethod || PrintDependencies || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDependencies)) {
1721       print_dependencies_on(tty);
1722       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1723     }
1724     if (printmethod || PrintExceptionHandlers) {
1725       print_handler_table();
1726       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1727       print_nul_chk_table();
1728       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1729     }
1730 
1731     if (printmethod) {
1732       print_recorded_oops();
1733       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1734       print_recorded_metadata();
1735       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1736     }
1737   }
1738 #endif
1739 
1740   if (xtty != nullptr) {
1741     xtty->tail("print_nmethod");
1742   }
1743 }
1744 
1745 
1746 // Promote one word from an assembly-time handle to a live embedded oop.
1747 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1748   if (handle == nullptr ||
1749       // As a special case, IC oops are initialized to 1 or -1.
1750       handle == (jobject) Universe::non_oop_word()) {
1751     *(void**)dest = handle;
1752   } else {
1753     *dest = JNIHandles::resolve_non_null(handle);
1754   }
1755 }
1756 
1757 
1758 // Have to have the same name because it's called by a template
1759 void nmethod::copy_values(GrowableArray<jobject>* array) {
1760   int length = array->length();
1761   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1762   oop* dest = oops_begin();
1763   for (int index = 0 ; index < length; index++) {
1764     initialize_immediate_oop(&dest[index], array->at(index));
1765   }
1766 
1767   // Now we can fix up all the oops in the code.  We need to do this
1768   // in the code because the assembler uses jobjects as placeholders.
1769   // The code and relocations have already been initialized by the
1770   // CodeBlob constructor, so it is valid even at this early point to
1771   // iterate over relocations and patch the code.
1772   fix_oop_relocations(nullptr, nullptr, /*initialize_immediates=*/ true);
1773 }
1774 
1775 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1776   int length = array->length();
1777   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1778   Metadata** dest = metadata_begin();
1779   for (int index = 0 ; index < length; index++) {
1780     dest[index] = array->at(index);
1781   }
1782 }
1783 
1784 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1785   // re-patch all oop-bearing instructions, just in case some oops moved
1786   RelocIterator iter(this, begin, end);
1787   while (iter.next()) {
1788     if (iter.type() == relocInfo::oop_type) {
1789       oop_Relocation* reloc = iter.oop_reloc();
1790       if (initialize_immediates && reloc->oop_is_immediate()) {
1791         oop* dest = reloc->oop_addr();
1792         jobject obj = *reinterpret_cast<jobject*>(dest);
1793         initialize_immediate_oop(dest, obj);
1794       }
1795       // Refresh the oop-related bits of this instruction.
1796       reloc->fix_oop_relocation();
1797     } else if (iter.type() == relocInfo::metadata_type) {
1798       metadata_Relocation* reloc = iter.metadata_reloc();
1799       reloc->fix_metadata_relocation();
1800     }
1801   }
1802 }
1803 
1804 static void install_post_call_nop_displacement(nmethod* nm, address pc) {
1805   NativePostCallNop* nop = nativePostCallNop_at((address) pc);
1806   intptr_t cbaddr = (intptr_t) nm;
1807   intptr_t offset = ((intptr_t) pc) - cbaddr;
1808 
1809   int oopmap_slot = nm->oop_maps()->find_slot_for_offset(int((intptr_t) pc - (intptr_t) nm->code_begin()));
1810   if (oopmap_slot < 0) { // this can happen at asynchronous (non-safepoint) stackwalks
1811     log_debug(codecache)("failed to find oopmap for cb: " INTPTR_FORMAT " offset: %d", cbaddr, (int) offset);
1812   } else if (!nop->patch(oopmap_slot, offset)) {
1813     log_debug(codecache)("failed to encode %d %d", oopmap_slot, (int) offset);
1814   }
1815 }
1816 
1817 void nmethod::finalize_relocations() {
1818   NoSafepointVerifier nsv;
1819 
1820   GrowableArray<NativeMovConstReg*> virtual_call_data;
1821 
1822   // Make sure that post call nops fill in nmethod offsets eagerly so
1823   // we don't have to race with deoptimization
1824   RelocIterator iter(this);
1825   while (iter.next()) {
1826     if (iter.type() == relocInfo::virtual_call_type) {
1827       virtual_call_Relocation* r = iter.virtual_call_reloc();
1828       NativeMovConstReg* value = nativeMovConstReg_at(r->cached_value());
1829       virtual_call_data.append(value);
1830     } else if (iter.type() == relocInfo::post_call_nop_type) {
1831       post_call_nop_Relocation* const reloc = iter.post_call_nop_reloc();
1832       address pc = reloc->addr();
1833       install_post_call_nop_displacement(this, pc);
1834     }
1835   }
1836 
1837   if (virtual_call_data.length() > 0) {
1838     // We allocate a block of CompiledICData per nmethod so the GC can purge this faster.
1839     _compiled_ic_data = new CompiledICData[virtual_call_data.length()];
1840     CompiledICData* next_data = _compiled_ic_data;
1841 
1842     for (NativeMovConstReg* value : virtual_call_data) {
1843       value->set_data((intptr_t)next_data);
1844       next_data++;
1845     }
1846   }
1847 }
1848 
1849 void nmethod::make_deoptimized() {
1850   if (!Continuations::enabled()) {
1851     // Don't deopt this again.
1852     set_deoptimized_done();
1853     return;
1854   }
1855 
1856   assert(method() == nullptr || can_be_deoptimized(), "");
1857 
1858   CompiledICLocker ml(this);
1859   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1860 
1861   // If post call nops have been already patched, we can just bail-out.
1862   if (has_been_deoptimized()) {
1863     return;
1864   }
1865 
1866   ResourceMark rm;
1867   RelocIterator iter(this, oops_reloc_begin());
1868 
1869   while (iter.next()) {
1870 
1871     switch (iter.type()) {
1872       case relocInfo::virtual_call_type: {
1873         CompiledIC *ic = CompiledIC_at(&iter);
1874         address pc = ic->end_of_call();
1875         NativePostCallNop* nop = nativePostCallNop_at(pc);
1876         if (nop != nullptr) {
1877           nop->make_deopt();
1878         }
1879         assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
1880         break;
1881       }
1882       case relocInfo::static_call_type:
1883       case relocInfo::opt_virtual_call_type: {
1884         CompiledDirectCall *csc = CompiledDirectCall::at(iter.reloc());
1885         address pc = csc->end_of_call();
1886         NativePostCallNop* nop = nativePostCallNop_at(pc);
1887         //tty->print_cr(" - static pc %p", pc);
1888         if (nop != nullptr) {
1889           nop->make_deopt();
1890         }
1891         // We can't assert here, there are some calls to stubs / runtime
1892         // that have reloc data and doesn't have a post call NOP.
1893         //assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
1894         break;
1895       }
1896       default:
1897         break;
1898     }
1899   }
1900   // Don't deopt this again.
1901   set_deoptimized_done();
1902 }
1903 
1904 void nmethod::verify_clean_inline_caches() {
1905   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1906 
1907   ResourceMark rm;
1908   RelocIterator iter(this, oops_reloc_begin());
1909   while(iter.next()) {
1910     switch(iter.type()) {
1911       case relocInfo::virtual_call_type: {
1912         CompiledIC *ic = CompiledIC_at(&iter);
1913         CodeBlob *cb = CodeCache::find_blob(ic->destination());
1914         assert(cb != nullptr, "destination not in CodeBlob?");
1915         nmethod* nm = cb->as_nmethod_or_null();
1916         if (nm != nullptr) {
1917           // Verify that inline caches pointing to bad nmethods are clean
1918           if (!nm->is_in_use() || nm->is_unloading()) {
1919             assert(ic->is_clean(), "IC should be clean");
1920           }
1921         }
1922         break;
1923       }
1924       case relocInfo::static_call_type:
1925       case relocInfo::opt_virtual_call_type: {
1926         CompiledDirectCall *cdc = CompiledDirectCall::at(iter.reloc());
1927         CodeBlob *cb = CodeCache::find_blob(cdc->destination());
1928         assert(cb != nullptr, "destination not in CodeBlob?");
1929         nmethod* nm = cb->as_nmethod_or_null();
1930         if (nm != nullptr) {
1931           // Verify that inline caches pointing to bad nmethods are clean
1932           if (!nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
1933             assert(cdc->is_clean(), "IC should be clean");
1934           }
1935         }
1936         break;
1937       }
1938       default:
1939         break;
1940     }
1941   }
1942 }
1943 
1944 void nmethod::mark_as_maybe_on_stack() {
1945   Atomic::store(&_gc_epoch, CodeCache::gc_epoch());
1946 }
1947 
1948 bool nmethod::is_maybe_on_stack() {
1949   // If the condition below is true, it means that the nmethod was found to
1950   // be alive the previous completed marking cycle.
1951   return Atomic::load(&_gc_epoch) >= CodeCache::previous_completed_gc_marking_cycle();
1952 }
1953 
1954 void nmethod::inc_decompile_count() {
1955   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1956   // Could be gated by ProfileTraps, but do not bother...
1957   Method* m = method();
1958   if (m == nullptr)  return;
1959   MethodData* mdo = m->method_data();
1960   if (mdo == nullptr)  return;
1961   // There is a benign race here.  See comments in methodData.hpp.
1962   mdo->inc_decompile_count();
1963 }
1964 
1965 bool nmethod::try_transition(signed char new_state_int) {
1966   signed char new_state = new_state_int;
1967   assert_lock_strong(NMethodState_lock);
1968   signed char old_state = _state;
1969   if (old_state >= new_state) {
1970     // Ensure monotonicity of transitions.
1971     return false;
1972   }
1973   Atomic::store(&_state, new_state);
1974   return true;
1975 }
1976 
1977 void nmethod::invalidate_osr_method() {
1978   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1979   // Remove from list of active nmethods
1980   if (method() != nullptr) {
1981     method()->method_holder()->remove_osr_nmethod(this);
1982   }
1983 }
1984 
1985 void nmethod::log_state_change(const char* reason) const {
1986   assert(reason != nullptr, "Must provide a reason");
1987 
1988   if (LogCompilation) {
1989     if (xtty != nullptr) {
1990       ttyLocker ttyl;  // keep the following output all in one block
1991       xtty->begin_elem("make_not_entrant thread='%zu' reason='%s'",
1992                        os::current_thread_id(), reason);
1993       log_identity(xtty);
1994       xtty->stamp();
1995       xtty->end_elem();
1996     }
1997   }
1998 
1999   ResourceMark rm;
2000   stringStream ss(NEW_RESOURCE_ARRAY(char, 256), 256);
2001   ss.print("made not entrant: %s", reason);
2002 
2003   CompileTask::print_ul(this, ss.freeze());
2004   if (PrintCompilation) {
2005     print_on_with_msg(tty, ss.freeze());
2006   }
2007 }
2008 
2009 void nmethod::unlink_from_method() {
2010   if (method() != nullptr) {
2011     method()->unlink_code(this);
2012   }
2013 }
2014 
2015 // Invalidate code
2016 bool nmethod::make_not_entrant(const char* reason) {
2017   assert(reason != nullptr, "Must provide a reason");
2018 
2019   // This can be called while the system is already at a safepoint which is ok
2020   NoSafepointVerifier nsv;
2021 
2022   if (is_unloading()) {
2023     // If the nmethod is unloading, then it is already not entrant through
2024     // the nmethod entry barriers. No need to do anything; GC will unload it.
2025     return false;
2026   }
2027 
2028   if (Atomic::load(&_state) == not_entrant) {
2029     // Avoid taking the lock if already in required state.
2030     // This is safe from races because the state is an end-state,
2031     // which the nmethod cannot back out of once entered.
2032     // No need for fencing either.
2033     return false;
2034   }
2035 
2036   {
2037     // Enter critical section.  Does not block for safepoint.
2038     ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
2039 
2040     if (Atomic::load(&_state) == not_entrant) {
2041       // another thread already performed this transition so nothing
2042       // to do, but return false to indicate this.
2043       return false;
2044     }
2045 
2046     if (is_osr_method()) {
2047       // This logic is equivalent to the logic below for patching the
2048       // verified entry point of regular methods.
2049       // this effectively makes the osr nmethod not entrant
2050       invalidate_osr_method();
2051     } else {
2052       // The caller can be calling the method statically or through an inline
2053       // cache call.
2054       NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
2055                                        SharedRuntime::get_handle_wrong_method_stub());
2056     }
2057 
2058     if (update_recompile_counts()) {
2059       // Mark the method as decompiled.
2060       inc_decompile_count();
2061     }
2062 
2063     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2064     if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2065       // If nmethod entry barriers are not supported, we won't mark
2066       // nmethods as on-stack when they become on-stack. So we
2067       // degrade to a less accurate flushing strategy, for now.
2068       mark_as_maybe_on_stack();
2069     }
2070 
2071     // Change state
2072     bool success = try_transition(not_entrant);
2073     assert(success, "Transition can't fail");
2074 
2075     // Log the transition once
2076     log_state_change(reason);
2077 
2078     // Remove nmethod from method.
2079     unlink_from_method();
2080 
2081   } // leave critical region under NMethodState_lock
2082 
2083 #if INCLUDE_JVMCI
2084   // Invalidate can't occur while holding the NMethodState_lock
2085   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2086   if (nmethod_data != nullptr) {
2087     nmethod_data->invalidate_nmethod_mirror(this);
2088   }
2089 #endif
2090 
2091 #ifdef ASSERT
2092   if (is_osr_method() && method() != nullptr) {
2093     // Make sure osr nmethod is invalidated, i.e. not on the list
2094     bool found = method()->method_holder()->remove_osr_nmethod(this);
2095     assert(!found, "osr nmethod should have been invalidated");
2096   }
2097 #endif
2098 
2099   return true;
2100 }
2101 
2102 // For concurrent GCs, there must be a handshake between unlink and flush
2103 void nmethod::unlink() {
2104   if (is_unlinked()) {
2105     // Already unlinked.
2106     return;
2107   }
2108 
2109   flush_dependencies();
2110 
2111   // unlink_from_method will take the NMethodState_lock.
2112   // In this case we don't strictly need it when unlinking nmethods from
2113   // the Method, because it is only concurrently unlinked by
2114   // the entry barrier, which acquires the per nmethod lock.
2115   unlink_from_method();
2116 
2117   if (is_osr_method()) {
2118     invalidate_osr_method();
2119   }
2120 
2121 #if INCLUDE_JVMCI
2122   // Clear the link between this nmethod and a HotSpotNmethod mirror
2123   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2124   if (nmethod_data != nullptr) {
2125     nmethod_data->invalidate_nmethod_mirror(this);
2126   }
2127 #endif
2128 
2129   // Post before flushing as jmethodID is being used
2130   post_compiled_method_unload();
2131 
2132   // Register for flushing when it is safe. For concurrent class unloading,
2133   // that would be after the unloading handshake, and for STW class unloading
2134   // that would be when getting back to the VM thread.
2135   ClassUnloadingContext::context()->register_unlinked_nmethod(this);
2136 }
2137 
2138 void nmethod::purge(bool unregister_nmethod) {
2139 
2140   MutexLocker ml(CodeCache_lock, Mutex::_no_safepoint_check_flag);
2141 
2142   // completely deallocate this method
2143   Events::log_nmethod_flush(Thread::current(), "flushing %s nmethod " INTPTR_FORMAT, is_osr_method() ? "osr" : "", p2i(this));
2144   log_debug(codecache)("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
2145                        "/Free CodeCache:%zuKb",
2146                        is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
2147                        CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
2148 
2149   // We need to deallocate any ExceptionCache data.
2150   // Note that we do not need to grab the nmethod lock for this, it
2151   // better be thread safe if we're disposing of it!
2152   ExceptionCache* ec = exception_cache();
2153   while(ec != nullptr) {
2154     ExceptionCache* next = ec->next();
2155     delete ec;
2156     ec = next;
2157   }
2158   if (_pc_desc_container != nullptr) {
2159     delete _pc_desc_container;
2160   }
2161   delete[] _compiled_ic_data;
2162 
2163   if (_immutable_data != blob_end()) {
2164     os::free(_immutable_data);
2165     _immutable_data = blob_end(); // Valid not null address
2166   }
2167   if (unregister_nmethod) {
2168     Universe::heap()->unregister_nmethod(this);
2169   }
2170   CodeCache::unregister_old_nmethod(this);
2171 
2172   CodeBlob::purge();
2173 }
2174 
2175 oop nmethod::oop_at(int index) const {
2176   if (index == 0) {
2177     return nullptr;
2178   }
2179 
2180   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2181   return bs_nm->oop_load_no_keepalive(this, index);
2182 }
2183 
2184 oop nmethod::oop_at_phantom(int index) const {
2185   if (index == 0) {
2186     return nullptr;
2187   }
2188 
2189   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2190   return bs_nm->oop_load_phantom(this, index);
2191 }
2192 
2193 //
2194 // Notify all classes this nmethod is dependent on that it is no
2195 // longer dependent.
2196 
2197 void nmethod::flush_dependencies() {
2198   if (!has_flushed_dependencies()) {
2199     set_has_flushed_dependencies(true);
2200     for (Dependencies::DepStream deps(this); deps.next(); ) {
2201       if (deps.type() == Dependencies::call_site_target_value) {
2202         // CallSite dependencies are managed on per-CallSite instance basis.
2203         oop call_site = deps.argument_oop(0);
2204         MethodHandles::clean_dependency_context(call_site);
2205       } else {
2206         InstanceKlass* ik = deps.context_type();
2207         if (ik == nullptr) {
2208           continue;  // ignore things like evol_method
2209         }
2210         // During GC liveness of dependee determines class that needs to be updated.
2211         // The GC may clean dependency contexts concurrently and in parallel.
2212         ik->clean_dependency_context();
2213       }
2214     }
2215   }
2216 }
2217 
2218 void nmethod::post_compiled_method(CompileTask* task) {
2219   task->mark_success();
2220   task->set_nm_content_size(content_size());
2221   task->set_nm_insts_size(insts_size());
2222   task->set_nm_total_size(total_size());
2223 
2224   // JVMTI -- compiled method notification (must be done outside lock)
2225   post_compiled_method_load_event();
2226 
2227   if (CompilationLog::log() != nullptr) {
2228     CompilationLog::log()->log_nmethod(JavaThread::current(), this);
2229   }
2230 
2231   const DirectiveSet* directive = task->directive();
2232   maybe_print_nmethod(directive);
2233 }
2234 
2235 // ------------------------------------------------------------------
2236 // post_compiled_method_load_event
2237 // new method for install_code() path
2238 // Transfer information from compilation to jvmti
2239 void nmethod::post_compiled_method_load_event(JvmtiThreadState* state) {
2240   // This is a bad time for a safepoint.  We don't want
2241   // this nmethod to get unloaded while we're queueing the event.
2242   NoSafepointVerifier nsv;
2243 
2244   Method* m = method();
2245   HOTSPOT_COMPILED_METHOD_LOAD(
2246       (char *) m->klass_name()->bytes(),
2247       m->klass_name()->utf8_length(),
2248       (char *) m->name()->bytes(),
2249       m->name()->utf8_length(),
2250       (char *) m->signature()->bytes(),
2251       m->signature()->utf8_length(),
2252       insts_begin(), insts_size());
2253 
2254 
2255   if (JvmtiExport::should_post_compiled_method_load()) {
2256     // Only post unload events if load events are found.
2257     set_load_reported();
2258     // If a JavaThread hasn't been passed in, let the Service thread
2259     // (which is a real Java thread) post the event
2260     JvmtiDeferredEvent event = JvmtiDeferredEvent::compiled_method_load_event(this);
2261     if (state == nullptr) {
2262       // Execute any barrier code for this nmethod as if it's called, since
2263       // keeping it alive looks like stack walking.
2264       run_nmethod_entry_barrier();
2265       ServiceThread::enqueue_deferred_event(&event);
2266     } else {
2267       // This enters the nmethod barrier outside in the caller.
2268       state->enqueue_event(&event);
2269     }
2270   }
2271 }
2272 
2273 void nmethod::post_compiled_method_unload() {
2274   assert(_method != nullptr, "just checking");
2275   DTRACE_METHOD_UNLOAD_PROBE(method());
2276 
2277   // If a JVMTI agent has enabled the CompiledMethodUnload event then
2278   // post the event. The Method* will not be valid when this is freed.
2279 
2280   // Don't bother posting the unload if the load event wasn't posted.
2281   if (load_reported() && JvmtiExport::should_post_compiled_method_unload()) {
2282     JvmtiDeferredEvent event =
2283       JvmtiDeferredEvent::compiled_method_unload_event(
2284           method()->jmethod_id(), insts_begin());
2285     ServiceThread::enqueue_deferred_event(&event);
2286   }
2287 }
2288 
2289 // Iterate over metadata calling this function.   Used by RedefineClasses
2290 void nmethod::metadata_do(MetadataClosure* f) {
2291   {
2292     // Visit all immediate references that are embedded in the instruction stream.
2293     RelocIterator iter(this, oops_reloc_begin());
2294     while (iter.next()) {
2295       if (iter.type() == relocInfo::metadata_type) {
2296         metadata_Relocation* r = iter.metadata_reloc();
2297         // In this metadata, we must only follow those metadatas directly embedded in
2298         // the code.  Other metadatas (oop_index>0) are seen as part of
2299         // the metadata section below.
2300         assert(1 == (r->metadata_is_immediate()) +
2301                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2302                "metadata must be found in exactly one place");
2303         if (r->metadata_is_immediate() && r->metadata_value() != nullptr) {
2304           Metadata* md = r->metadata_value();
2305           if (md != _method) f->do_metadata(md);
2306         }
2307       } else if (iter.type() == relocInfo::virtual_call_type) {
2308         // Check compiledIC holders associated with this nmethod
2309         ResourceMark rm;
2310         CompiledIC *ic = CompiledIC_at(&iter);
2311         ic->metadata_do(f);
2312       }
2313     }
2314   }
2315 
2316   // Visit the metadata section
2317   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2318     if (*p == Universe::non_oop_word() || *p == nullptr)  continue;  // skip non-oops
2319     Metadata* md = *p;
2320     f->do_metadata(md);
2321   }
2322 
2323   // Visit metadata not embedded in the other places.
2324   if (_method != nullptr) f->do_metadata(_method);
2325 }
2326 
2327 // Heuristic for nuking nmethods even though their oops are live.
2328 // Main purpose is to reduce code cache pressure and get rid of
2329 // nmethods that don't seem to be all that relevant any longer.
2330 bool nmethod::is_cold() {
2331   if (!MethodFlushing || is_native_method() || is_not_installed()) {
2332     // No heuristic unloading at all
2333     return false;
2334   }
2335 
2336   if (!is_maybe_on_stack() && is_not_entrant()) {
2337     // Not entrant nmethods that are not on any stack can just
2338     // be removed
2339     return true;
2340   }
2341 
2342   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2343   if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2344     // On platforms that don't support nmethod entry barriers, we can't
2345     // trust the temporal aspect of the gc epochs. So we can't detect
2346     // cold nmethods on such platforms.
2347     return false;
2348   }
2349 
2350   if (!UseCodeCacheFlushing) {
2351     // Bail out if we don't heuristically remove nmethods
2352     return false;
2353   }
2354 
2355   // Other code can be phased out more gradually after N GCs
2356   return CodeCache::previous_completed_gc_marking_cycle() > _gc_epoch + 2 * CodeCache::cold_gc_count();
2357 }
2358 
2359 // The _is_unloading_state encodes a tuple comprising the unloading cycle
2360 // and the result of IsUnloadingBehaviour::is_unloading() for that cycle.
2361 // This is the bit layout of the _is_unloading_state byte: 00000CCU
2362 // CC refers to the cycle, which has 2 bits, and U refers to the result of
2363 // IsUnloadingBehaviour::is_unloading() for that unloading cycle.
2364 
2365 class IsUnloadingState: public AllStatic {
2366   static const uint8_t _is_unloading_mask = 1;
2367   static const uint8_t _is_unloading_shift = 0;
2368   static const uint8_t _unloading_cycle_mask = 6;
2369   static const uint8_t _unloading_cycle_shift = 1;
2370 
2371   static uint8_t set_is_unloading(uint8_t state, bool value) {
2372     state &= (uint8_t)~_is_unloading_mask;
2373     if (value) {
2374       state |= 1 << _is_unloading_shift;
2375     }
2376     assert(is_unloading(state) == value, "unexpected unloading cycle overflow");
2377     return state;
2378   }
2379 
2380   static uint8_t set_unloading_cycle(uint8_t state, uint8_t value) {
2381     state &= (uint8_t)~_unloading_cycle_mask;
2382     state |= (uint8_t)(value << _unloading_cycle_shift);
2383     assert(unloading_cycle(state) == value, "unexpected unloading cycle overflow");
2384     return state;
2385   }
2386 
2387 public:
2388   static bool is_unloading(uint8_t state) { return (state & _is_unloading_mask) >> _is_unloading_shift == 1; }
2389   static uint8_t unloading_cycle(uint8_t state) { return (state & _unloading_cycle_mask) >> _unloading_cycle_shift; }
2390 
2391   static uint8_t create(bool is_unloading, uint8_t unloading_cycle) {
2392     uint8_t state = 0;
2393     state = set_is_unloading(state, is_unloading);
2394     state = set_unloading_cycle(state, unloading_cycle);
2395     return state;
2396   }
2397 };
2398 
2399 bool nmethod::is_unloading() {
2400   uint8_t state = Atomic::load(&_is_unloading_state);
2401   bool state_is_unloading = IsUnloadingState::is_unloading(state);
2402   if (state_is_unloading) {
2403     return true;
2404   }
2405   uint8_t state_unloading_cycle = IsUnloadingState::unloading_cycle(state);
2406   uint8_t current_cycle = CodeCache::unloading_cycle();
2407   if (state_unloading_cycle == current_cycle) {
2408     return false;
2409   }
2410 
2411   // The IsUnloadingBehaviour is responsible for calculating if the nmethod
2412   // should be unloaded. This can be either because there is a dead oop,
2413   // or because is_cold() heuristically determines it is time to unload.
2414   state_unloading_cycle = current_cycle;
2415   state_is_unloading = IsUnloadingBehaviour::is_unloading(this);
2416   uint8_t new_state = IsUnloadingState::create(state_is_unloading, state_unloading_cycle);
2417 
2418   // Note that if an nmethod has dead oops, everyone will agree that the
2419   // nmethod is_unloading. However, the is_cold heuristics can yield
2420   // different outcomes, so we guard the computed result with a CAS
2421   // to ensure all threads have a shared view of whether an nmethod
2422   // is_unloading or not.
2423   uint8_t found_state = Atomic::cmpxchg(&_is_unloading_state, state, new_state, memory_order_relaxed);
2424 
2425   if (found_state == state) {
2426     // First to change state, we win
2427     return state_is_unloading;
2428   } else {
2429     // State already set, so use it
2430     return IsUnloadingState::is_unloading(found_state);
2431   }
2432 }
2433 
2434 void nmethod::clear_unloading_state() {
2435   uint8_t state = IsUnloadingState::create(false, CodeCache::unloading_cycle());
2436   Atomic::store(&_is_unloading_state, state);
2437 }
2438 
2439 
2440 // This is called at the end of the strong tracing/marking phase of a
2441 // GC to unload an nmethod if it contains otherwise unreachable
2442 // oops or is heuristically found to be not important.
2443 void nmethod::do_unloading(bool unloading_occurred) {
2444   // Make sure the oop's ready to receive visitors
2445   if (is_unloading()) {
2446     unlink();
2447   } else {
2448     unload_nmethod_caches(unloading_occurred);
2449     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2450     if (bs_nm != nullptr) {
2451       bs_nm->disarm(this);
2452     }
2453   }
2454 }
2455 
2456 void nmethod::oops_do(OopClosure* f, bool allow_dead) {
2457   // Prevent extra code cache walk for platforms that don't have immediate oops.
2458   if (relocInfo::mustIterateImmediateOopsInCode()) {
2459     RelocIterator iter(this, oops_reloc_begin());
2460 
2461     while (iter.next()) {
2462       if (iter.type() == relocInfo::oop_type ) {
2463         oop_Relocation* r = iter.oop_reloc();
2464         // In this loop, we must only follow those oops directly embedded in
2465         // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
2466         assert(1 == (r->oop_is_immediate()) +
2467                (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2468                "oop must be found in exactly one place");
2469         if (r->oop_is_immediate() && r->oop_value() != nullptr) {
2470           f->do_oop(r->oop_addr());
2471         }
2472       }
2473     }
2474   }
2475 
2476   // Scopes
2477   // This includes oop constants not inlined in the code stream.
2478   for (oop* p = oops_begin(); p < oops_end(); p++) {
2479     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
2480     f->do_oop(p);
2481   }
2482 }
2483 
2484 void nmethod::follow_nmethod(OopIterateClosure* cl) {
2485   // Process oops in the nmethod
2486   oops_do(cl);
2487 
2488   // CodeCache unloading support
2489   mark_as_maybe_on_stack();
2490 
2491   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2492   bs_nm->disarm(this);
2493 
2494   // There's an assumption made that this function is not used by GCs that
2495   // relocate objects, and therefore we don't call fix_oop_relocations.
2496 }
2497 
2498 nmethod* volatile nmethod::_oops_do_mark_nmethods;
2499 
2500 void nmethod::oops_do_log_change(const char* state) {
2501   LogTarget(Trace, gc, nmethod) lt;
2502   if (lt.is_enabled()) {
2503     LogStream ls(lt);
2504     CompileTask::print(&ls, this, state, true /* short_form */);
2505   }
2506 }
2507 
2508 bool nmethod::oops_do_try_claim() {
2509   if (oops_do_try_claim_weak_request()) {
2510     nmethod* result = oops_do_try_add_to_list_as_weak_done();
2511     assert(result == nullptr, "adding to global list as weak done must always succeed.");
2512     return true;
2513   }
2514   return false;
2515 }
2516 
2517 bool nmethod::oops_do_try_claim_weak_request() {
2518   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2519 
2520   if ((_oops_do_mark_link == nullptr) &&
2521       (Atomic::replace_if_null(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag)))) {
2522     oops_do_log_change("oops_do, mark weak request");
2523     return true;
2524   }
2525   return false;
2526 }
2527 
2528 void nmethod::oops_do_set_strong_done(nmethod* old_head) {
2529   _oops_do_mark_link = mark_link(old_head, claim_strong_done_tag);
2530 }
2531 
2532 nmethod::oops_do_mark_link* nmethod::oops_do_try_claim_strong_done() {
2533   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2534 
2535   oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, mark_link(nullptr, claim_weak_request_tag), mark_link(this, claim_strong_done_tag));
2536   if (old_next == nullptr) {
2537     oops_do_log_change("oops_do, mark strong done");
2538   }
2539   return old_next;
2540 }
2541 
2542 nmethod::oops_do_mark_link* nmethod::oops_do_try_add_strong_request(nmethod::oops_do_mark_link* next) {
2543   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2544   assert(next == mark_link(this, claim_weak_request_tag), "Should be claimed as weak");
2545 
2546   oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(this, claim_strong_request_tag));
2547   if (old_next == next) {
2548     oops_do_log_change("oops_do, mark strong request");
2549   }
2550   return old_next;
2551 }
2552 
2553 bool nmethod::oops_do_try_claim_weak_done_as_strong_done(nmethod::oops_do_mark_link* next) {
2554   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2555   assert(extract_state(next) == claim_weak_done_tag, "Should be claimed as weak done");
2556 
2557   oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(extract_nmethod(next), claim_strong_done_tag));
2558   if (old_next == next) {
2559     oops_do_log_change("oops_do, mark weak done -> mark strong done");
2560     return true;
2561   }
2562   return false;
2563 }
2564 
2565 nmethod* nmethod::oops_do_try_add_to_list_as_weak_done() {
2566   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2567 
2568   assert(extract_state(_oops_do_mark_link) == claim_weak_request_tag ||
2569          extract_state(_oops_do_mark_link) == claim_strong_request_tag,
2570          "must be but is nmethod " PTR_FORMAT " %u", p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
2571 
2572   nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this);
2573   // Self-loop if needed.
2574   if (old_head == nullptr) {
2575     old_head = this;
2576   }
2577   // Try to install end of list and weak done tag.
2578   if (Atomic::cmpxchg(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag), mark_link(old_head, claim_weak_done_tag)) == mark_link(this, claim_weak_request_tag)) {
2579     oops_do_log_change("oops_do, mark weak done");
2580     return nullptr;
2581   } else {
2582     return old_head;
2583   }
2584 }
2585 
2586 void nmethod::oops_do_add_to_list_as_strong_done() {
2587   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2588 
2589   nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this);
2590   // Self-loop if needed.
2591   if (old_head == nullptr) {
2592     old_head = this;
2593   }
2594   assert(_oops_do_mark_link == mark_link(this, claim_strong_done_tag), "must be but is nmethod " PTR_FORMAT " state %u",
2595          p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
2596 
2597   oops_do_set_strong_done(old_head);
2598 }
2599 
2600 void nmethod::oops_do_process_weak(OopsDoProcessor* p) {
2601   if (!oops_do_try_claim_weak_request()) {
2602     // Failed to claim for weak processing.
2603     oops_do_log_change("oops_do, mark weak request fail");
2604     return;
2605   }
2606 
2607   p->do_regular_processing(this);
2608 
2609   nmethod* old_head = oops_do_try_add_to_list_as_weak_done();
2610   if (old_head == nullptr) {
2611     return;
2612   }
2613   oops_do_log_change("oops_do, mark weak done fail");
2614   // Adding to global list failed, another thread added a strong request.
2615   assert(extract_state(_oops_do_mark_link) == claim_strong_request_tag,
2616          "must be but is %u", extract_state(_oops_do_mark_link));
2617 
2618   oops_do_log_change("oops_do, mark weak request -> mark strong done");
2619 
2620   oops_do_set_strong_done(old_head);
2621   // Do missing strong processing.
2622   p->do_remaining_strong_processing(this);
2623 }
2624 
2625 void nmethod::oops_do_process_strong(OopsDoProcessor* p) {
2626   oops_do_mark_link* next_raw = oops_do_try_claim_strong_done();
2627   if (next_raw == nullptr) {
2628     p->do_regular_processing(this);
2629     oops_do_add_to_list_as_strong_done();
2630     return;
2631   }
2632   // Claim failed. Figure out why and handle it.
2633   if (oops_do_has_weak_request(next_raw)) {
2634     oops_do_mark_link* old = next_raw;
2635     // Claim failed because being weak processed (state == "weak request").
2636     // Try to request deferred strong processing.
2637     next_raw = oops_do_try_add_strong_request(old);
2638     if (next_raw == old) {
2639       // Successfully requested deferred strong processing.
2640       return;
2641     }
2642     // Failed because of a concurrent transition. No longer in "weak request" state.
2643   }
2644   if (oops_do_has_any_strong_state(next_raw)) {
2645     // Already claimed for strong processing or requested for such.
2646     return;
2647   }
2648   if (oops_do_try_claim_weak_done_as_strong_done(next_raw)) {
2649     // Successfully claimed "weak done" as "strong done". Do the missing marking.
2650     p->do_remaining_strong_processing(this);
2651     return;
2652   }
2653   // Claim failed, some other thread got it.
2654 }
2655 
2656 void nmethod::oops_do_marking_prologue() {
2657   assert_at_safepoint();
2658 
2659   log_trace(gc, nmethod)("oops_do_marking_prologue");
2660   assert(_oops_do_mark_nmethods == nullptr, "must be empty");
2661 }
2662 
2663 void nmethod::oops_do_marking_epilogue() {
2664   assert_at_safepoint();
2665 
2666   nmethod* next = _oops_do_mark_nmethods;
2667   _oops_do_mark_nmethods = nullptr;
2668   if (next != nullptr) {
2669     nmethod* cur;
2670     do {
2671       cur = next;
2672       next = extract_nmethod(cur->_oops_do_mark_link);
2673       cur->_oops_do_mark_link = nullptr;
2674       DEBUG_ONLY(cur->verify_oop_relocations());
2675 
2676       LogTarget(Trace, gc, nmethod) lt;
2677       if (lt.is_enabled()) {
2678         LogStream ls(lt);
2679         CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
2680       }
2681       // End if self-loop has been detected.
2682     } while (cur != next);
2683   }
2684   log_trace(gc, nmethod)("oops_do_marking_epilogue");
2685 }
2686 
2687 inline bool includes(void* p, void* from, void* to) {
2688   return from <= p && p < to;
2689 }
2690 
2691 
2692 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2693   assert(count >= 2, "must be sentinel values, at least");
2694 
2695 #ifdef ASSERT
2696   // must be sorted and unique; we do a binary search in find_pc_desc()
2697   int prev_offset = pcs[0].pc_offset();
2698   assert(prev_offset == PcDesc::lower_offset_limit,
2699          "must start with a sentinel");
2700   for (int i = 1; i < count; i++) {
2701     int this_offset = pcs[i].pc_offset();
2702     assert(this_offset > prev_offset, "offsets must be sorted");
2703     prev_offset = this_offset;
2704   }
2705   assert(prev_offset == PcDesc::upper_offset_limit,
2706          "must end with a sentinel");
2707 #endif //ASSERT
2708 
2709   // Search for MethodHandle invokes and tag the nmethod.
2710   for (int i = 0; i < count; i++) {
2711     if (pcs[i].is_method_handle_invoke()) {
2712       set_has_method_handle_invokes(true);
2713       break;
2714     }
2715   }
2716   assert(has_method_handle_invokes() == (_deopt_mh_handler_offset != -1), "must have deopt mh handler");
2717 
2718   int size = count * sizeof(PcDesc);
2719   assert(scopes_pcs_size() >= size, "oob");
2720   memcpy(scopes_pcs_begin(), pcs, size);
2721 
2722   // Adjust the final sentinel downward.
2723   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2724   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2725   last_pc->set_pc_offset(content_size() + 1);
2726   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2727     // Fill any rounding gaps with copies of the last record.
2728     last_pc[1] = last_pc[0];
2729   }
2730   // The following assert could fail if sizeof(PcDesc) is not
2731   // an integral multiple of oopSize (the rounding term).
2732   // If it fails, change the logic to always allocate a multiple
2733   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2734   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2735 }
2736 
2737 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2738   assert(scopes_data_size() >= size, "oob");
2739   memcpy(scopes_data_begin(), buffer, size);
2740 }
2741 
2742 #ifdef ASSERT
2743 static PcDesc* linear_search(int pc_offset, bool approximate, PcDesc* lower, PcDesc* upper) {
2744   PcDesc* res = nullptr;
2745   assert(lower != nullptr && lower->pc_offset() == PcDesc::lower_offset_limit,
2746          "must start with a sentinel");
2747   // lower + 1 to exclude initial sentinel
2748   for (PcDesc* p = lower + 1; p < upper; p++) {
2749     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
2750     if (match_desc(p, pc_offset, approximate)) {
2751       if (res == nullptr) {
2752         res = p;
2753       } else {
2754         res = (PcDesc*) badAddress;
2755       }
2756     }
2757   }
2758   return res;
2759 }
2760 #endif
2761 
2762 
2763 #ifndef PRODUCT
2764 // Version of method to collect statistic
2765 PcDesc* PcDescContainer::find_pc_desc(address pc, bool approximate, address code_begin,
2766                                       PcDesc* lower, PcDesc* upper) {
2767   ++pc_nmethod_stats.pc_desc_queries;
2768   if (approximate) ++pc_nmethod_stats.pc_desc_approx;
2769 
2770   PcDesc* desc = _pc_desc_cache.last_pc_desc();
2771   assert(desc != nullptr, "PcDesc cache should be initialized already");
2772   if (desc->pc_offset() == (pc - code_begin)) {
2773     // Cached value matched
2774     ++pc_nmethod_stats.pc_desc_tests;
2775     ++pc_nmethod_stats.pc_desc_repeats;
2776     return desc;
2777   }
2778   return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
2779 }
2780 #endif
2781 
2782 // Finds a PcDesc with real-pc equal to "pc"
2783 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, address code_begin,
2784                                                PcDesc* lower_incl, PcDesc* upper_incl) {
2785   if ((pc < code_begin) ||
2786       (pc - code_begin) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2787     return nullptr;  // PC is wildly out of range
2788   }
2789   int pc_offset = (int) (pc - code_begin);
2790 
2791   // Check the PcDesc cache if it contains the desired PcDesc
2792   // (This as an almost 100% hit rate.)
2793   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2794   if (res != nullptr) {
2795     assert(res == linear_search(pc_offset, approximate, lower_incl, upper_incl), "cache ok");
2796     return res;
2797   }
2798 
2799   // Fallback algorithm: quasi-linear search for the PcDesc
2800   // Find the last pc_offset less than the given offset.
2801   // The successor must be the required match, if there is a match at all.
2802   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2803   PcDesc* lower = lower_incl;     // this is initial sentinel
2804   PcDesc* upper = upper_incl - 1; // exclude final sentinel
2805   if (lower >= upper)  return nullptr;  // no PcDescs at all
2806 
2807 #define assert_LU_OK \
2808   /* invariant on lower..upper during the following search: */ \
2809   assert(lower->pc_offset() <  pc_offset, "sanity"); \
2810   assert(upper->pc_offset() >= pc_offset, "sanity")
2811   assert_LU_OK;
2812 
2813   // Use the last successful return as a split point.
2814   PcDesc* mid = _pc_desc_cache.last_pc_desc();
2815   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2816   if (mid->pc_offset() < pc_offset) {
2817     lower = mid;
2818   } else {
2819     upper = mid;
2820   }
2821 
2822   // Take giant steps at first (4096, then 256, then 16, then 1)
2823   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2824   const int RADIX = (1 << LOG2_RADIX);
2825   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2826     while ((mid = lower + step) < upper) {
2827       assert_LU_OK;
2828       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2829       if (mid->pc_offset() < pc_offset) {
2830         lower = mid;
2831       } else {
2832         upper = mid;
2833         break;
2834       }
2835     }
2836     assert_LU_OK;
2837   }
2838 
2839   // Sneak up on the value with a linear search of length ~16.
2840   while (true) {
2841     assert_LU_OK;
2842     mid = lower + 1;
2843     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2844     if (mid->pc_offset() < pc_offset) {
2845       lower = mid;
2846     } else {
2847       upper = mid;
2848       break;
2849     }
2850   }
2851 #undef assert_LU_OK
2852 
2853   if (match_desc(upper, pc_offset, approximate)) {
2854     assert(upper == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
2855     if (!Thread::current_in_asgct()) {
2856       // we don't want to modify the cache if we're in ASGCT
2857       // which is typically called in a signal handler
2858       _pc_desc_cache.add_pc_desc(upper);
2859     }
2860     return upper;
2861   } else {
2862     assert(nullptr == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
2863     return nullptr;
2864   }
2865 }
2866 
2867 bool nmethod::check_dependency_on(DepChange& changes) {
2868   // What has happened:
2869   // 1) a new class dependee has been added
2870   // 2) dependee and all its super classes have been marked
2871   bool found_check = false;  // set true if we are upset
2872   for (Dependencies::DepStream deps(this); deps.next(); ) {
2873     // Evaluate only relevant dependencies.
2874     if (deps.spot_check_dependency_at(changes) != nullptr) {
2875       found_check = true;
2876       NOT_DEBUG(break);
2877     }
2878   }
2879   return found_check;
2880 }
2881 
2882 // Called from mark_for_deoptimization, when dependee is invalidated.
2883 bool nmethod::is_dependent_on_method(Method* dependee) {
2884   for (Dependencies::DepStream deps(this); deps.next(); ) {
2885     if (deps.type() != Dependencies::evol_method)
2886       continue;
2887     Method* method = deps.method_argument(0);
2888     if (method == dependee) return true;
2889   }
2890   return false;
2891 }
2892 
2893 void nmethod_init() {
2894   // make sure you didn't forget to adjust the filler fields
2895   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2896 }
2897 
2898 // -----------------------------------------------------------------------------
2899 // Verification
2900 
2901 class VerifyOopsClosure: public OopClosure {
2902   nmethod* _nm;
2903   bool     _ok;
2904 public:
2905   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2906   bool ok() { return _ok; }
2907   virtual void do_oop(oop* p) {
2908     if (oopDesc::is_oop_or_null(*p)) return;
2909     // Print diagnostic information before calling print_nmethod().
2910     // Assertions therein might prevent call from returning.
2911     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2912                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2913     if (_ok) {
2914       _nm->print_nmethod(true);
2915       _ok = false;
2916     }
2917   }
2918   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2919 };
2920 
2921 class VerifyMetadataClosure: public MetadataClosure {
2922  public:
2923   void do_metadata(Metadata* md) {
2924     if (md->is_method()) {
2925       Method* method = (Method*)md;
2926       assert(!method->is_old(), "Should not be installing old methods");
2927     }
2928   }
2929 };
2930 
2931 
2932 void nmethod::verify() {
2933   if (is_not_entrant())
2934     return;
2935 
2936   // Make sure all the entry points are correctly aligned for patching.
2937   NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2938 
2939   // assert(oopDesc::is_oop(method()), "must be valid");
2940 
2941   ResourceMark rm;
2942 
2943   if (!CodeCache::contains(this)) {
2944     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2945   }
2946 
2947   if(is_native_method() )
2948     return;
2949 
2950   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2951   if (nm != this) {
2952     fatal("find_nmethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2953   }
2954 
2955   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2956     if (! p->verify(this)) {
2957       tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2958     }
2959   }
2960 
2961 #ifdef ASSERT
2962 #if INCLUDE_JVMCI
2963   {
2964     // Verify that implicit exceptions that deoptimize have a PcDesc and OopMap
2965     ImmutableOopMapSet* oms = oop_maps();
2966     ImplicitExceptionTable implicit_table(this);
2967     for (uint i = 0; i < implicit_table.len(); i++) {
2968       int exec_offset = (int) implicit_table.get_exec_offset(i);
2969       if (implicit_table.get_exec_offset(i) == implicit_table.get_cont_offset(i)) {
2970         assert(pc_desc_at(code_begin() + exec_offset) != nullptr, "missing PcDesc");
2971         bool found = false;
2972         for (int i = 0, imax = oms->count(); i < imax; i++) {
2973           if (oms->pair_at(i)->pc_offset() == exec_offset) {
2974             found = true;
2975             break;
2976           }
2977         }
2978         assert(found, "missing oopmap");
2979       }
2980     }
2981   }
2982 #endif
2983 #endif
2984 
2985   VerifyOopsClosure voc(this);
2986   oops_do(&voc);
2987   assert(voc.ok(), "embedded oops must be OK");
2988   Universe::heap()->verify_nmethod(this);
2989 
2990   assert(_oops_do_mark_link == nullptr, "_oops_do_mark_link for %s should be nullptr but is " PTR_FORMAT,
2991          nm->method()->external_name(), p2i(_oops_do_mark_link));
2992   verify_scopes();
2993 
2994   CompiledICLocker nm_verify(this);
2995   VerifyMetadataClosure vmc;
2996   metadata_do(&vmc);
2997 }
2998 
2999 
3000 void nmethod::verify_interrupt_point(address call_site, bool is_inline_cache) {
3001 
3002   // Verify IC only when nmethod installation is finished.
3003   if (!is_not_installed()) {
3004     if (CompiledICLocker::is_safe(this)) {
3005       if (is_inline_cache) {
3006         CompiledIC_at(this, call_site);
3007       } else {
3008         CompiledDirectCall::at(call_site);
3009       }
3010     } else {
3011       CompiledICLocker ml_verify(this);
3012       if (is_inline_cache) {
3013         CompiledIC_at(this, call_site);
3014       } else {
3015         CompiledDirectCall::at(call_site);
3016       }
3017     }
3018   }
3019 
3020   HandleMark hm(Thread::current());
3021 
3022   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
3023   assert(pd != nullptr, "PcDesc must exist");
3024   for (ScopeDesc* sd = new ScopeDesc(this, pd);
3025        !sd->is_top(); sd = sd->sender()) {
3026     sd->verify();
3027   }
3028 }
3029 
3030 void nmethod::verify_scopes() {
3031   if( !method() ) return;       // Runtime stubs have no scope
3032   if (method()->is_native()) return; // Ignore stub methods.
3033   // iterate through all interrupt point
3034   // and verify the debug information is valid.
3035   RelocIterator iter(this);
3036   while (iter.next()) {
3037     address stub = nullptr;
3038     switch (iter.type()) {
3039       case relocInfo::virtual_call_type:
3040         verify_interrupt_point(iter.addr(), true /* is_inline_cache */);
3041         break;
3042       case relocInfo::opt_virtual_call_type:
3043         stub = iter.opt_virtual_call_reloc()->static_stub();
3044         verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3045         break;
3046       case relocInfo::static_call_type:
3047         stub = iter.static_call_reloc()->static_stub();
3048         verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3049         break;
3050       case relocInfo::runtime_call_type:
3051       case relocInfo::runtime_call_w_cp_type: {
3052         address destination = iter.reloc()->value();
3053         // Right now there is no way to find out which entries support
3054         // an interrupt point.  It would be nice if we had this
3055         // information in a table.
3056         break;
3057       }
3058       default:
3059         break;
3060     }
3061     assert(stub == nullptr || stub_contains(stub), "static call stub outside stub section");
3062   }
3063 }
3064 
3065 
3066 // -----------------------------------------------------------------------------
3067 // Printing operations
3068 
3069 void nmethod::print_on_impl(outputStream* st) const {
3070   ResourceMark rm;
3071 
3072   st->print("Compiled method ");
3073 
3074   if (is_compiled_by_c1()) {
3075     st->print("(c1) ");
3076   } else if (is_compiled_by_c2()) {
3077     st->print("(c2) ");
3078   } else if (is_compiled_by_jvmci()) {
3079     st->print("(JVMCI) ");
3080   } else {
3081     st->print("(n/a) ");
3082   }
3083 
3084   print_on_with_msg(st, nullptr);
3085 
3086   if (WizardMode) {
3087     st->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
3088     st->print(" for method " INTPTR_FORMAT , p2i(method()));
3089     st->print(" { ");
3090     st->print_cr("%s ", state());
3091     st->print_cr("}:");
3092   }
3093   if (size              () > 0) st->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3094                                              p2i(this),
3095                                              p2i(this) + size(),
3096                                              size());
3097   if (consts_size       () > 0) st->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3098                                              p2i(consts_begin()),
3099                                              p2i(consts_end()),
3100                                              consts_size());
3101   if (insts_size        () > 0) st->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3102                                              p2i(insts_begin()),
3103                                              p2i(insts_end()),
3104                                              insts_size());
3105   if (stub_size         () > 0) st->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3106                                              p2i(stub_begin()),
3107                                              p2i(stub_end()),
3108                                              stub_size());
3109   if (oops_size         () > 0) st->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3110                                              p2i(oops_begin()),
3111                                              p2i(oops_end()),
3112                                              oops_size());
3113   if (mutable_data_size() > 0) st->print_cr(" mutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3114                                              p2i(mutable_data_begin()),
3115                                              p2i(mutable_data_end()),
3116                                              mutable_data_size());
3117   if (relocation_size() > 0)   st->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3118                                              p2i(relocation_begin()),
3119                                              p2i(relocation_end()),
3120                                              relocation_size());
3121   if (metadata_size     () > 0) st->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3122                                              p2i(metadata_begin()),
3123                                              p2i(metadata_end()),
3124                                              metadata_size());
3125 #if INCLUDE_JVMCI
3126   if (jvmci_data_size   () > 0) st->print_cr(" JVMCI data     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3127                                              p2i(jvmci_data_begin()),
3128                                              p2i(jvmci_data_end()),
3129                                              jvmci_data_size());
3130 #endif
3131   if (immutable_data_size() > 0) st->print_cr(" immutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3132                                              p2i(immutable_data_begin()),
3133                                              p2i(immutable_data_end()),
3134                                              immutable_data_size());
3135   if (dependencies_size () > 0) st->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3136                                              p2i(dependencies_begin()),
3137                                              p2i(dependencies_end()),
3138                                              dependencies_size());
3139   if (nul_chk_table_size() > 0) st->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3140                                              p2i(nul_chk_table_begin()),
3141                                              p2i(nul_chk_table_end()),
3142                                              nul_chk_table_size());
3143   if (handler_table_size() > 0) st->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3144                                              p2i(handler_table_begin()),
3145                                              p2i(handler_table_end()),
3146                                              handler_table_size());
3147   if (scopes_pcs_size   () > 0) st->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3148                                              p2i(scopes_pcs_begin()),
3149                                              p2i(scopes_pcs_end()),
3150                                              scopes_pcs_size());
3151   if (scopes_data_size  () > 0) st->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3152                                              p2i(scopes_data_begin()),
3153                                              p2i(scopes_data_end()),
3154                                              scopes_data_size());
3155 #if INCLUDE_JVMCI
3156   if (speculations_size () > 0) st->print_cr(" speculations   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3157                                              p2i(speculations_begin()),
3158                                              p2i(speculations_end()),
3159                                              speculations_size());
3160 #endif
3161 }
3162 
3163 void nmethod::print_code() {
3164   ResourceMark m;
3165   ttyLocker ttyl;
3166   // Call the specialized decode method of this class.
3167   decode(tty);
3168 }
3169 
3170 #ifndef PRODUCT  // called InstanceKlass methods are available only then. Declared as PRODUCT_RETURN
3171 
3172 void nmethod::print_dependencies_on(outputStream* out) {
3173   ResourceMark rm;
3174   stringStream st;
3175   st.print_cr("Dependencies:");
3176   for (Dependencies::DepStream deps(this); deps.next(); ) {
3177     deps.print_dependency(&st);
3178     InstanceKlass* ctxk = deps.context_type();
3179     if (ctxk != nullptr) {
3180       if (ctxk->is_dependent_nmethod(this)) {
3181         st.print_cr("   [nmethod<=klass]%s", ctxk->external_name());
3182       }
3183     }
3184     deps.log_dependency();  // put it into the xml log also
3185   }
3186   out->print_raw(st.as_string());
3187 }
3188 #endif
3189 
3190 #if defined(SUPPORT_DATA_STRUCTS)
3191 
3192 // Print the oops from the underlying CodeBlob.
3193 void nmethod::print_oops(outputStream* st) {
3194   ResourceMark m;
3195   st->print("Oops:");
3196   if (oops_begin() < oops_end()) {
3197     st->cr();
3198     for (oop* p = oops_begin(); p < oops_end(); p++) {
3199       Disassembler::print_location((unsigned char*)p, (unsigned char*)oops_begin(), (unsigned char*)oops_end(), st, true, false);
3200       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3201       if (Universe::contains_non_oop_word(p)) {
3202         st->print_cr("NON_OOP");
3203         continue;  // skip non-oops
3204       }
3205       if (*p == nullptr) {
3206         st->print_cr("nullptr-oop");
3207         continue;  // skip non-oops
3208       }
3209       (*p)->print_value_on(st);
3210       st->cr();
3211     }
3212   } else {
3213     st->print_cr(" <list empty>");
3214   }
3215 }
3216 
3217 // Print metadata pool.
3218 void nmethod::print_metadata(outputStream* st) {
3219   ResourceMark m;
3220   st->print("Metadata:");
3221   if (metadata_begin() < metadata_end()) {
3222     st->cr();
3223     for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
3224       Disassembler::print_location((unsigned char*)p, (unsigned char*)metadata_begin(), (unsigned char*)metadata_end(), st, true, false);
3225       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3226       if (*p && *p != Universe::non_oop_word()) {
3227         (*p)->print_value_on(st);
3228       }
3229       st->cr();
3230     }
3231   } else {
3232     st->print_cr(" <list empty>");
3233   }
3234 }
3235 
3236 #ifndef PRODUCT  // ScopeDesc::print_on() is available only then. Declared as PRODUCT_RETURN
3237 void nmethod::print_scopes_on(outputStream* st) {
3238   // Find the first pc desc for all scopes in the code and print it.
3239   ResourceMark rm;
3240   st->print("scopes:");
3241   if (scopes_pcs_begin() < scopes_pcs_end()) {
3242     st->cr();
3243     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3244       if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
3245         continue;
3246 
3247       ScopeDesc* sd = scope_desc_at(p->real_pc(this));
3248       while (sd != nullptr) {
3249         sd->print_on(st, p);  // print output ends with a newline
3250         sd = sd->sender();
3251       }
3252     }
3253   } else {
3254     st->print_cr(" <list empty>");
3255   }
3256 }
3257 #endif
3258 
3259 #ifndef PRODUCT  // RelocIterator does support printing only then.
3260 void nmethod::print_relocations() {
3261   ResourceMark m;       // in case methods get printed via the debugger
3262   tty->print_cr("relocations:");
3263   RelocIterator iter(this);
3264   iter.print();
3265 }
3266 #endif
3267 
3268 void nmethod::print_pcs_on(outputStream* st) {
3269   ResourceMark m;       // in case methods get printed via debugger
3270   st->print("pc-bytecode offsets:");
3271   if (scopes_pcs_begin() < scopes_pcs_end()) {
3272     st->cr();
3273     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3274       p->print_on(st, this);  // print output ends with a newline
3275     }
3276   } else {
3277     st->print_cr(" <list empty>");
3278   }
3279 }
3280 
3281 void nmethod::print_handler_table() {
3282   ExceptionHandlerTable(this).print(code_begin());
3283 }
3284 
3285 void nmethod::print_nul_chk_table() {
3286   ImplicitExceptionTable(this).print(code_begin());
3287 }
3288 
3289 void nmethod::print_recorded_oop(int log_n, int i) {
3290   void* value;
3291 
3292   if (i == 0) {
3293     value = nullptr;
3294   } else {
3295     // Be careful around non-oop words. Don't create an oop
3296     // with that value, or it will assert in verification code.
3297     if (Universe::contains_non_oop_word(oop_addr_at(i))) {
3298       value = Universe::non_oop_word();
3299     } else {
3300       value = oop_at(i);
3301     }
3302   }
3303 
3304   tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(value));
3305 
3306   if (value == Universe::non_oop_word()) {
3307     tty->print("non-oop word");
3308   } else {
3309     if (value == nullptr) {
3310       tty->print("nullptr-oop");
3311     } else {
3312       oop_at(i)->print_value_on(tty);
3313     }
3314   }
3315 
3316   tty->cr();
3317 }
3318 
3319 void nmethod::print_recorded_oops() {
3320   const int n = oops_count();
3321   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3322   tty->print("Recorded oops:");
3323   if (n > 0) {
3324     tty->cr();
3325     for (int i = 0; i < n; i++) {
3326       print_recorded_oop(log_n, i);
3327     }
3328   } else {
3329     tty->print_cr(" <list empty>");
3330   }
3331 }
3332 
3333 void nmethod::print_recorded_metadata() {
3334   const int n = metadata_count();
3335   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3336   tty->print("Recorded metadata:");
3337   if (n > 0) {
3338     tty->cr();
3339     for (int i = 0; i < n; i++) {
3340       Metadata* m = metadata_at(i);
3341       tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(m));
3342       if (m == (Metadata*)Universe::non_oop_word()) {
3343         tty->print("non-metadata word");
3344       } else if (m == nullptr) {
3345         tty->print("nullptr-oop");
3346       } else {
3347         Metadata::print_value_on_maybe_null(tty, m);
3348       }
3349       tty->cr();
3350     }
3351   } else {
3352     tty->print_cr(" <list empty>");
3353   }
3354 }
3355 #endif
3356 
3357 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
3358 
3359 void nmethod::print_constant_pool(outputStream* st) {
3360   //-----------------------------------
3361   //---<  Print the constant pool  >---
3362   //-----------------------------------
3363   int consts_size = this->consts_size();
3364   if ( consts_size > 0 ) {
3365     unsigned char* cstart = this->consts_begin();
3366     unsigned char* cp     = cstart;
3367     unsigned char* cend   = cp + consts_size;
3368     unsigned int   bytes_per_line = 4;
3369     unsigned int   CP_alignment   = 8;
3370     unsigned int   n;
3371 
3372     st->cr();
3373 
3374     //---<  print CP header to make clear what's printed  >---
3375     if( ((uintptr_t)cp&(CP_alignment-1)) == 0 ) {
3376       n = bytes_per_line;
3377       st->print_cr("[Constant Pool]");
3378       Disassembler::print_location(cp, cstart, cend, st, true, true);
3379       Disassembler::print_hexdata(cp, n, st, true);
3380       st->cr();
3381     } else {
3382       n = (int)((uintptr_t)cp & (bytes_per_line-1));
3383       st->print_cr("[Constant Pool (unaligned)]");
3384     }
3385 
3386     //---<  print CP contents, bytes_per_line at a time  >---
3387     while (cp < cend) {
3388       Disassembler::print_location(cp, cstart, cend, st, true, false);
3389       Disassembler::print_hexdata(cp, n, st, false);
3390       cp += n;
3391       n   = bytes_per_line;
3392       st->cr();
3393     }
3394 
3395     //---<  Show potential alignment gap between constant pool and code  >---
3396     cend = code_begin();
3397     if( cp < cend ) {
3398       n = 4;
3399       st->print_cr("[Code entry alignment]");
3400       while (cp < cend) {
3401         Disassembler::print_location(cp, cstart, cend, st, false, false);
3402         cp += n;
3403         st->cr();
3404       }
3405     }
3406   } else {
3407     st->print_cr("[Constant Pool (empty)]");
3408   }
3409   st->cr();
3410 }
3411 
3412 #endif
3413 
3414 // Disassemble this nmethod.
3415 // Print additional debug information, if requested. This could be code
3416 // comments, block comments, profiling counters, etc.
3417 // The undisassembled format is useful no disassembler library is available.
3418 // The resulting hex dump (with markers) can be disassembled later, or on
3419 // another system, when/where a disassembler library is available.
3420 void nmethod::decode2(outputStream* ost) const {
3421 
3422   // Called from frame::back_trace_with_decode without ResourceMark.
3423   ResourceMark rm;
3424 
3425   // Make sure we have a valid stream to print on.
3426   outputStream* st = ost ? ost : tty;
3427 
3428 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) && ! defined(SUPPORT_ASSEMBLY)
3429   const bool use_compressed_format    = true;
3430   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3431                                                                   AbstractDisassembler::show_block_comment());
3432 #else
3433   const bool use_compressed_format    = Disassembler::is_abstract();
3434   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3435                                                                   AbstractDisassembler::show_block_comment());
3436 #endif
3437 
3438   st->cr();
3439   this->print_on(st);
3440   st->cr();
3441 
3442 #if defined(SUPPORT_ASSEMBLY)
3443   //----------------------------------
3444   //---<  Print real disassembly  >---
3445   //----------------------------------
3446   if (! use_compressed_format) {
3447     st->print_cr("[Disassembly]");
3448     Disassembler::decode(const_cast<nmethod*>(this), st);
3449     st->bol();
3450     st->print_cr("[/Disassembly]");
3451     return;
3452   }
3453 #endif
3454 
3455 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3456 
3457   // Compressed undisassembled disassembly format.
3458   // The following status values are defined/supported:
3459   //   = 0 - currently at bol() position, nothing printed yet on current line.
3460   //   = 1 - currently at position after print_location().
3461   //   > 1 - in the midst of printing instruction stream bytes.
3462   int        compressed_format_idx    = 0;
3463   int        code_comment_column      = 0;
3464   const int  instr_maxlen             = Assembler::instr_maxlen();
3465   const uint tabspacing               = 8;
3466   unsigned char* start = this->code_begin();
3467   unsigned char* p     = this->code_begin();
3468   unsigned char* end   = this->code_end();
3469   unsigned char* pss   = p; // start of a code section (used for offsets)
3470 
3471   if ((start == nullptr) || (end == nullptr)) {
3472     st->print_cr("PrintAssembly not possible due to uninitialized section pointers");
3473     return;
3474   }
3475 #endif
3476 
3477 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3478   //---<  plain abstract disassembly, no comments or anything, just section headers  >---
3479   if (use_compressed_format && ! compressed_with_comments) {
3480     const_cast<nmethod*>(this)->print_constant_pool(st);
3481 
3482     //---<  Open the output (Marker for post-mortem disassembler)  >---
3483     st->print_cr("[MachCode]");
3484     const char* header = nullptr;
3485     address p0 = p;
3486     while (p < end) {
3487       address pp = p;
3488       while ((p < end) && (header == nullptr)) {
3489         header = nmethod_section_label(p);
3490         pp  = p;
3491         p  += Assembler::instr_len(p);
3492       }
3493       if (pp > p0) {
3494         AbstractDisassembler::decode_range_abstract(p0, pp, start, end, st, Assembler::instr_maxlen());
3495         p0 = pp;
3496         p  = pp;
3497         header = nullptr;
3498       } else if (header != nullptr) {
3499         st->bol();
3500         st->print_cr("%s", header);
3501         header = nullptr;
3502       }
3503     }
3504     //---<  Close the output (Marker for post-mortem disassembler)  >---
3505     st->bol();
3506     st->print_cr("[/MachCode]");
3507     return;
3508   }
3509 #endif
3510 
3511 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3512   //---<  abstract disassembly with comments and section headers merged in  >---
3513   if (compressed_with_comments) {
3514     const_cast<nmethod*>(this)->print_constant_pool(st);
3515 
3516     //---<  Open the output (Marker for post-mortem disassembler)  >---
3517     st->print_cr("[MachCode]");
3518     while ((p < end) && (p != nullptr)) {
3519       const int instruction_size_in_bytes = Assembler::instr_len(p);
3520 
3521       //---<  Block comments for nmethod. Interrupts instruction stream, if any.  >---
3522       // Outputs a bol() before and a cr() after, but only if a comment is printed.
3523       // Prints nmethod_section_label as well.
3524       if (AbstractDisassembler::show_block_comment()) {
3525         print_block_comment(st, p);
3526         if (st->position() == 0) {
3527           compressed_format_idx = 0;
3528         }
3529       }
3530 
3531       //---<  New location information after line break  >---
3532       if (compressed_format_idx == 0) {
3533         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
3534         compressed_format_idx = 1;
3535       }
3536 
3537       //---<  Code comment for current instruction. Address range [p..(p+len))  >---
3538       unsigned char* p_end = p + (ssize_t)instruction_size_in_bytes;
3539       S390_ONLY(if (p_end > end) p_end = end;) // avoid getting past the end
3540 
3541       if (AbstractDisassembler::show_comment() && const_cast<nmethod*>(this)->has_code_comment(p, p_end)) {
3542         //---<  interrupt instruction byte stream for code comment  >---
3543         if (compressed_format_idx > 1) {
3544           st->cr();  // interrupt byte stream
3545           st->cr();  // add an empty line
3546           code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
3547         }
3548         const_cast<nmethod*>(this)->print_code_comment_on(st, code_comment_column, p, p_end );
3549         st->bol();
3550         compressed_format_idx = 0;
3551       }
3552 
3553       //---<  New location information after line break  >---
3554       if (compressed_format_idx == 0) {
3555         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
3556         compressed_format_idx = 1;
3557       }
3558 
3559       //---<  Nicely align instructions for readability  >---
3560       if (compressed_format_idx > 1) {
3561         Disassembler::print_delimiter(st);
3562       }
3563 
3564       //---<  Now, finally, print the actual instruction bytes  >---
3565       unsigned char* p0 = p;
3566       p = Disassembler::decode_instruction_abstract(p, st, instruction_size_in_bytes, instr_maxlen);
3567       compressed_format_idx += (int)(p - p0);
3568 
3569       if (Disassembler::start_newline(compressed_format_idx-1)) {
3570         st->cr();
3571         compressed_format_idx = 0;
3572       }
3573     }
3574     //---<  Close the output (Marker for post-mortem disassembler)  >---
3575     st->bol();
3576     st->print_cr("[/MachCode]");
3577     return;
3578   }
3579 #endif
3580 }
3581 
3582 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
3583 
3584 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
3585   RelocIterator iter(this, begin, end);
3586   bool have_one = false;
3587   while (iter.next()) {
3588     have_one = true;
3589     switch (iter.type()) {
3590         case relocInfo::none: {
3591           // Skip it and check next
3592           break;
3593         }
3594         case relocInfo::oop_type: {
3595           // Get a non-resizable resource-allocated stringStream.
3596           // Our callees make use of (nested) ResourceMarks.
3597           stringStream st(NEW_RESOURCE_ARRAY(char, 1024), 1024);
3598           oop_Relocation* r = iter.oop_reloc();
3599           oop obj = r->oop_value();
3600           st.print("oop(");
3601           if (obj == nullptr) st.print("nullptr");
3602           else obj->print_value_on(&st);
3603           st.print(")");
3604           return st.as_string();
3605         }
3606         case relocInfo::metadata_type: {
3607           stringStream st;
3608           metadata_Relocation* r = iter.metadata_reloc();
3609           Metadata* obj = r->metadata_value();
3610           st.print("metadata(");
3611           if (obj == nullptr) st.print("nullptr");
3612           else obj->print_value_on(&st);
3613           st.print(")");
3614           return st.as_string();
3615         }
3616         case relocInfo::runtime_call_type:
3617         case relocInfo::runtime_call_w_cp_type: {
3618           stringStream st;
3619           st.print("runtime_call");
3620           CallRelocation* r = (CallRelocation*)iter.reloc();
3621           address dest = r->destination();
3622           if (StubRoutines::contains(dest)) {
3623             StubCodeDesc* desc = StubCodeDesc::desc_for(dest);
3624             if (desc == nullptr) {
3625               desc = StubCodeDesc::desc_for(dest + frame::pc_return_offset);
3626             }
3627             if (desc != nullptr) {
3628               st.print(" Stub::%s", desc->name());
3629               return st.as_string();
3630             }
3631           }
3632           CodeBlob* cb = CodeCache::find_blob(dest);
3633           if (cb != nullptr) {
3634             st.print(" %s", cb->name());
3635           } else {
3636             ResourceMark rm;
3637             const int buflen = 1024;
3638             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
3639             int offset;
3640             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
3641               st.print(" %s", buf);
3642               if (offset != 0) {
3643                 st.print("+%d", offset);
3644               }
3645             }
3646           }
3647           return st.as_string();
3648         }
3649         case relocInfo::virtual_call_type: {
3650           stringStream st;
3651           st.print_raw("virtual_call");
3652           virtual_call_Relocation* r = iter.virtual_call_reloc();
3653           Method* m = r->method_value();
3654           if (m != nullptr) {
3655             assert(m->is_method(), "");
3656             m->print_short_name(&st);
3657           }
3658           return st.as_string();
3659         }
3660         case relocInfo::opt_virtual_call_type: {
3661           stringStream st;
3662           st.print_raw("optimized virtual_call");
3663           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
3664           Method* m = r->method_value();
3665           if (m != nullptr) {
3666             assert(m->is_method(), "");
3667             m->print_short_name(&st);
3668           }
3669           return st.as_string();
3670         }
3671         case relocInfo::static_call_type: {
3672           stringStream st;
3673           st.print_raw("static_call");
3674           static_call_Relocation* r = iter.static_call_reloc();
3675           Method* m = r->method_value();
3676           if (m != nullptr) {
3677             assert(m->is_method(), "");
3678             m->print_short_name(&st);
3679           }
3680           return st.as_string();
3681         }
3682         case relocInfo::static_stub_type:      return "static_stub";
3683         case relocInfo::external_word_type:    return "external_word";
3684         case relocInfo::internal_word_type:    return "internal_word";
3685         case relocInfo::section_word_type:     return "section_word";
3686         case relocInfo::poll_type:             return "poll";
3687         case relocInfo::poll_return_type:      return "poll_return";
3688         case relocInfo::trampoline_stub_type:  return "trampoline_stub";
3689         case relocInfo::entry_guard_type:      return "entry_guard";
3690         case relocInfo::post_call_nop_type:    return "post_call_nop";
3691         case relocInfo::barrier_type: {
3692           barrier_Relocation* const reloc = iter.barrier_reloc();
3693           stringStream st;
3694           st.print("barrier format=%d", reloc->format());
3695           return st.as_string();
3696         }
3697 
3698         case relocInfo::type_mask:             return "type_bit_mask";
3699 
3700         default: {
3701           stringStream st;
3702           st.print("unknown relocInfo=%d", (int) iter.type());
3703           return st.as_string();
3704         }
3705     }
3706   }
3707   return have_one ? "other" : nullptr;
3708 }
3709 
3710 // Return the last scope in (begin..end]
3711 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
3712   PcDesc* p = pc_desc_near(begin+1);
3713   if (p != nullptr && p->real_pc(this) <= end) {
3714     return new ScopeDesc(this, p);
3715   }
3716   return nullptr;
3717 }
3718 
3719 const char* nmethod::nmethod_section_label(address pos) const {
3720   const char* label = nullptr;
3721   if (pos == code_begin())                                              label = "[Instructions begin]";
3722   if (pos == entry_point())                                             label = "[Entry Point]";
3723   if (pos == inline_entry_point())                                      label = "[Inline Entry Point]";
3724   if (pos == verified_entry_point())                                    label = "[Verified Entry Point]";
3725   if (pos == verified_inline_entry_point())                             label = "[Verified Inline Entry Point]";
3726   if (pos == verified_inline_ro_entry_point())                          label = "[Verified Inline Entry Point (RO)]";
3727   if (has_method_handle_invokes() && (pos == deopt_mh_handler_begin())) label = "[Deopt MH Handler Code]";
3728   if (pos == consts_begin() && pos != insts_begin())                    label = "[Constants]";
3729   // Check stub_code before checking exception_handler or deopt_handler.
3730   if (pos == this->stub_begin())                                        label = "[Stub Code]";
3731   if (JVMCI_ONLY(_exception_offset >= 0 &&) pos == exception_begin())          label = "[Exception Handler]";
3732   if (JVMCI_ONLY(_deopt_handler_offset != -1 &&) pos == deopt_handler_begin()) label = "[Deopt Handler Code]";
3733   return label;
3734 }
3735 
3736 static int maybe_print_entry_label(outputStream* stream, address pos, address entry, const char* label) {
3737   if (pos == entry) {
3738     stream->bol();
3739     stream->print_cr("%s", label);
3740     return 1;
3741   } else {
3742     return 0;
3743   }
3744 }
3745 
3746 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels) const {
3747   if (print_section_labels) {
3748     int n = 0;
3749     // Multiple entry points may be at the same position. Print them all.
3750     n += maybe_print_entry_label(stream, block_begin, entry_point(),                    "[Entry Point]");
3751     n += maybe_print_entry_label(stream, block_begin, inline_entry_point(),             "[Inline Entry Point]");
3752     n += maybe_print_entry_label(stream, block_begin, verified_entry_point(),           "[Verified Entry Point]");
3753     n += maybe_print_entry_label(stream, block_begin, verified_inline_entry_point(),    "[Verified Inline Entry Point]");
3754     n += maybe_print_entry_label(stream, block_begin, verified_inline_ro_entry_point(), "[Verified Inline Entry Point (RO)]");
3755     if (n == 0) {
3756       const char* label = nmethod_section_label(block_begin);
3757       if (label != nullptr) {
3758         stream->bol();
3759         stream->print_cr("%s", label);
3760       }
3761     }
3762   }
3763 
3764   Method* m = method();
3765   if (m == nullptr || is_osr_method()) {
3766     return;
3767   }
3768 
3769   // Print the name of the method (only once)
3770   address low = MIN4(entry_point(), verified_entry_point(), verified_inline_entry_point(), verified_inline_ro_entry_point());
3771   low = MIN2(low, inline_entry_point());
3772   assert(low != 0, "sanity");
3773   if (block_begin == low) {
3774     stream->print("  # ");
3775     m->print_value_on(stream);
3776     stream->cr();
3777   }
3778 
3779   // Print the arguments for the 3 types of verified entry points
3780   CompiledEntrySignature ces(m);
3781   ces.compute_calling_conventions(false);
3782   const GrowableArray<SigEntry>* sig_cc;
3783   const VMRegPair* regs;
3784   if (block_begin == verified_entry_point()) {
3785     sig_cc = ces.sig_cc();
3786     regs = ces.regs_cc();
3787   } else if (block_begin == verified_inline_entry_point()) {
3788     sig_cc = ces.sig();
3789     regs = ces.regs();
3790   } else if (block_begin == verified_inline_ro_entry_point()) {
3791     sig_cc = ces.sig_cc_ro();
3792     regs = ces.regs_cc_ro();
3793   } else {
3794     return;
3795   }
3796 
3797   bool has_this = !m->is_static();
3798   if (ces.has_inline_recv() && block_begin == verified_entry_point()) {
3799     // <this> argument is scalarized for verified_entry_point()
3800     has_this = false;
3801   }
3802   const char* spname = "sp"; // make arch-specific?
3803   int stack_slot_offset = this->frame_size() * wordSize;
3804   int tab1 = 14, tab2 = 24;
3805   int sig_index = 0;
3806   int arg_index = has_this ? -1 : 0;
3807   bool did_old_sp = false;
3808   for (ExtendedSignature sig = ExtendedSignature(sig_cc, SigEntryFilter()); !sig.at_end(); ++sig) {
3809     bool at_this = (arg_index == -1);
3810     bool at_old_sp = false;
3811     BasicType t = (*sig)._bt;
3812     if (at_this) {
3813       stream->print("  # this: ");
3814     } else {
3815       stream->print("  # parm%d: ", arg_index);
3816     }
3817     stream->move_to(tab1);
3818     VMReg fst = regs[sig_index].first();
3819     VMReg snd = regs[sig_index].second();
3820     if (fst->is_reg()) {
3821       stream->print("%s", fst->name());
3822       if (snd->is_valid())  {
3823         stream->print(":%s", snd->name());
3824       }
3825     } else if (fst->is_stack()) {
3826       int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
3827       if (offset == stack_slot_offset)  at_old_sp = true;
3828       stream->print("[%s+0x%x]", spname, offset);
3829     } else {
3830       stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
3831     }
3832     stream->print(" ");
3833     stream->move_to(tab2);
3834     stream->print("= ");
3835     if (at_this) {
3836       m->method_holder()->print_value_on(stream);
3837     } else {
3838       bool did_name = false;
3839       if (is_reference_type(t)) {
3840         Symbol* name = (*sig)._symbol;
3841         name->print_value_on(stream);
3842         did_name = true;
3843       }
3844       if (!did_name)
3845         stream->print("%s", type2name(t));
3846       // If the entry has a non-default sort_offset, it must be a null marker
3847       if ((*sig)._sort_offset != (*sig)._offset) {
3848         stream->print(" (null marker)");
3849       }
3850     }
3851     if (at_old_sp) {
3852       stream->print("  (%s of caller)", spname);
3853       did_old_sp = true;
3854     }
3855     stream->cr();
3856     sig_index += type2size[t];
3857     arg_index += 1;
3858   }
3859   if (!did_old_sp) {
3860     stream->print("  # ");
3861     stream->move_to(tab1);
3862     stream->print("[%s+0x%x]", spname, stack_slot_offset);
3863     stream->print("  (%s of caller)", spname);
3864     stream->cr();
3865   }
3866 }
3867 
3868 // Returns whether this nmethod has code comments.
3869 bool nmethod::has_code_comment(address begin, address end) {
3870   // scopes?
3871   ScopeDesc* sd  = scope_desc_in(begin, end);
3872   if (sd != nullptr) return true;
3873 
3874   // relocations?
3875   const char* str = reloc_string_for(begin, end);
3876   if (str != nullptr) return true;
3877 
3878   // implicit exceptions?
3879   int cont_offset = ImplicitExceptionTable(this).continuation_offset((uint)(begin - code_begin()));
3880   if (cont_offset != 0) return true;
3881 
3882   return false;
3883 }
3884 
3885 void nmethod::print_code_comment_on(outputStream* st, int column, address begin, address end) {
3886   ImplicitExceptionTable implicit_table(this);
3887   int pc_offset = (int)(begin - code_begin());
3888   int cont_offset = implicit_table.continuation_offset(pc_offset);
3889   bool oop_map_required = false;
3890   if (cont_offset != 0) {
3891     st->move_to(column, 6, 0);
3892     if (pc_offset == cont_offset) {
3893       st->print("; implicit exception: deoptimizes");
3894       oop_map_required = true;
3895     } else {
3896       st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
3897     }
3898   }
3899 
3900   // Find an oopmap in (begin, end].  We use the odd half-closed
3901   // interval so that oop maps and scope descs which are tied to the
3902   // byte after a call are printed with the call itself.  OopMaps
3903   // associated with implicit exceptions are printed with the implicit
3904   // instruction.
3905   address base = code_begin();
3906   ImmutableOopMapSet* oms = oop_maps();
3907   if (oms != nullptr) {
3908     for (int i = 0, imax = oms->count(); i < imax; i++) {
3909       const ImmutableOopMapPair* pair = oms->pair_at(i);
3910       const ImmutableOopMap* om = pair->get_from(oms);
3911       address pc = base + pair->pc_offset();
3912       if (pc >= begin) {
3913 #if INCLUDE_JVMCI
3914         bool is_implicit_deopt = implicit_table.continuation_offset(pair->pc_offset()) == (uint) pair->pc_offset();
3915 #else
3916         bool is_implicit_deopt = false;
3917 #endif
3918         if (is_implicit_deopt ? pc == begin : pc > begin && pc <= end) {
3919           st->move_to(column, 6, 0);
3920           st->print("; ");
3921           om->print_on(st);
3922           oop_map_required = false;
3923         }
3924       }
3925       if (pc > end) {
3926         break;
3927       }
3928     }
3929   }
3930   assert(!oop_map_required, "missed oopmap");
3931 
3932   Thread* thread = Thread::current();
3933 
3934   // Print any debug info present at this pc.
3935   ScopeDesc* sd  = scope_desc_in(begin, end);
3936   if (sd != nullptr) {
3937     st->move_to(column, 6, 0);
3938     if (sd->bci() == SynchronizationEntryBCI) {
3939       st->print(";*synchronization entry");
3940     } else if (sd->bci() == AfterBci) {
3941       st->print(";* method exit (unlocked if synchronized)");
3942     } else if (sd->bci() == UnwindBci) {
3943       st->print(";* unwind (locked if synchronized)");
3944     } else if (sd->bci() == AfterExceptionBci) {
3945       st->print(";* unwind (unlocked if synchronized)");
3946     } else if (sd->bci() == UnknownBci) {
3947       st->print(";* unknown");
3948     } else if (sd->bci() == InvalidFrameStateBci) {
3949       st->print(";* invalid frame state");
3950     } else {
3951       if (sd->method() == nullptr) {
3952         st->print("method is nullptr");
3953       } else if (sd->method()->is_native()) {
3954         st->print("method is native");
3955       } else {
3956         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
3957         st->print(";*%s", Bytecodes::name(bc));
3958         switch (bc) {
3959         case Bytecodes::_invokevirtual:
3960         case Bytecodes::_invokespecial:
3961         case Bytecodes::_invokestatic:
3962         case Bytecodes::_invokeinterface:
3963           {
3964             Bytecode_invoke invoke(methodHandle(thread, sd->method()), sd->bci());
3965             st->print(" ");
3966             if (invoke.name() != nullptr)
3967               invoke.name()->print_symbol_on(st);
3968             else
3969               st->print("<UNKNOWN>");
3970             break;
3971           }
3972         case Bytecodes::_getfield:
3973         case Bytecodes::_putfield:
3974         case Bytecodes::_getstatic:
3975         case Bytecodes::_putstatic:
3976           {
3977             Bytecode_field field(methodHandle(thread, sd->method()), sd->bci());
3978             st->print(" ");
3979             if (field.name() != nullptr)
3980               field.name()->print_symbol_on(st);
3981             else
3982               st->print("<UNKNOWN>");
3983           }
3984         default:
3985           break;
3986         }
3987       }
3988       st->print(" {reexecute=%d rethrow=%d return_oop=%d return_scalarized=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop(), sd->return_scalarized());
3989     }
3990 
3991     // Print all scopes
3992     for (;sd != nullptr; sd = sd->sender()) {
3993       st->move_to(column, 6, 0);
3994       st->print("; -");
3995       if (sd->should_reexecute()) {
3996         st->print(" (reexecute)");
3997       }
3998       if (sd->method() == nullptr) {
3999         st->print("method is nullptr");
4000       } else {
4001         sd->method()->print_short_name(st);
4002       }
4003       int lineno = sd->method()->line_number_from_bci(sd->bci());
4004       if (lineno != -1) {
4005         st->print("@%d (line %d)", sd->bci(), lineno);
4006       } else {
4007         st->print("@%d", sd->bci());
4008       }
4009       st->cr();
4010     }
4011   }
4012 
4013   // Print relocation information
4014   // Prevent memory leak: allocating without ResourceMark.
4015   ResourceMark rm;
4016   const char* str = reloc_string_for(begin, end);
4017   if (str != nullptr) {
4018     if (sd != nullptr) st->cr();
4019     st->move_to(column, 6, 0);
4020     st->print(";   {%s}", str);
4021   }
4022 }
4023 
4024 #endif
4025 
4026 address nmethod::call_instruction_address(address pc) const {
4027   if (NativeCall::is_call_before(pc)) {
4028     NativeCall *ncall = nativeCall_before(pc);
4029     return ncall->instruction_address();
4030   }
4031   return nullptr;
4032 }
4033 
4034 void nmethod::print_value_on_impl(outputStream* st) const {
4035   st->print_cr("nmethod");
4036 #if defined(SUPPORT_DATA_STRUCTS)
4037   print_on_with_msg(st, nullptr);
4038 #endif
4039 }
4040 
4041 #ifndef PRODUCT
4042 
4043 void nmethod::print_calls(outputStream* st) {
4044   RelocIterator iter(this);
4045   while (iter.next()) {
4046     switch (iter.type()) {
4047     case relocInfo::virtual_call_type: {
4048       CompiledICLocker ml_verify(this);
4049       CompiledIC_at(&iter)->print();
4050       break;
4051     }
4052     case relocInfo::static_call_type:
4053     case relocInfo::opt_virtual_call_type:
4054       st->print_cr("Direct call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
4055       CompiledDirectCall::at(iter.reloc())->print();
4056       break;
4057     default:
4058       break;
4059     }
4060   }
4061 }
4062 
4063 void nmethod::print_statistics() {
4064   ttyLocker ttyl;
4065   if (xtty != nullptr)  xtty->head("statistics type='nmethod'");
4066   native_nmethod_stats.print_native_nmethod_stats();
4067 #ifdef COMPILER1
4068   c1_java_nmethod_stats.print_nmethod_stats("C1");
4069 #endif
4070 #ifdef COMPILER2
4071   c2_java_nmethod_stats.print_nmethod_stats("C2");
4072 #endif
4073 #if INCLUDE_JVMCI
4074   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
4075 #endif
4076   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
4077   DebugInformationRecorder::print_statistics();
4078   pc_nmethod_stats.print_pc_stats();
4079   Dependencies::print_statistics();
4080   ExternalsRecorder::print_statistics();
4081   if (xtty != nullptr)  xtty->tail("statistics");
4082 }
4083 
4084 #endif // !PRODUCT
4085 
4086 #if INCLUDE_JVMCI
4087 void nmethod::update_speculation(JavaThread* thread) {
4088   jlong speculation = thread->pending_failed_speculation();
4089   if (speculation != 0) {
4090     guarantee(jvmci_nmethod_data() != nullptr, "failed speculation in nmethod without failed speculation list");
4091     jvmci_nmethod_data()->add_failed_speculation(this, speculation);
4092     thread->set_pending_failed_speculation(0);
4093   }
4094 }
4095 
4096 const char* nmethod::jvmci_name() {
4097   if (jvmci_nmethod_data() != nullptr) {
4098     return jvmci_nmethod_data()->name();
4099   }
4100   return nullptr;
4101 }
4102 #endif