1 /*
   2  * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "asm/assembler.inline.hpp"
  27 #include "code/codeCache.hpp"
  28 #include "code/compiledIC.hpp"
  29 #include "code/compiledMethod.inline.hpp"
  30 #include "code/dependencies.hpp"
  31 #include "code/nativeInst.hpp"
  32 #include "code/nmethod.hpp"
  33 #include "code/scopeDesc.hpp"
  34 #include "compiler/abstractCompiler.hpp"
  35 #include "compiler/compilationLog.hpp"
  36 #include "compiler/compileBroker.hpp"
  37 #include "compiler/compileLog.hpp"
  38 #include "compiler/compileTask.hpp"
  39 #include "compiler/compilerDirectives.hpp"
  40 #include "compiler/directivesParser.hpp"
  41 #include "compiler/disassembler.hpp"
  42 #include "compiler/oopMap.inline.hpp"
  43 #include "gc/shared/barrierSet.hpp"
  44 #include "gc/shared/barrierSetNMethod.hpp"
  45 #include "gc/shared/collectedHeap.hpp"
  46 #include "interpreter/bytecode.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 //---------------------------------------------------------------------------------
 113 // NMethod statistics
 114 // They are printed under various flags, including:
 115 //   PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
 116 // (In the latter two cases, they like other stats are printed to the log only.)
 117 
 118 #ifndef PRODUCT
 119 // These variables are put into one block to reduce relocations
 120 // and make it simpler to print from the debugger.
 121 struct java_nmethod_stats_struct {
 122   uint nmethod_count;
 123   uint total_size;
 124   uint relocation_size;
 125   uint consts_size;
 126   uint insts_size;
 127   uint stub_size;
 128   uint scopes_data_size;
 129   uint scopes_pcs_size;
 130   uint dependencies_size;
 131   uint handler_table_size;
 132   uint nul_chk_table_size;
 133 #if INCLUDE_JVMCI
 134   uint speculations_size;
 135   uint jvmci_data_size;
 136 #endif
 137   uint oops_size;
 138   uint metadata_size;
 139 
 140   void note_nmethod(nmethod* nm) {
 141     nmethod_count += 1;
 142     total_size          += nm->size();
 143     relocation_size     += nm->relocation_size();
 144     consts_size         += nm->consts_size();
 145     insts_size          += nm->insts_size();
 146     stub_size           += nm->stub_size();
 147     oops_size           += nm->oops_size();
 148     metadata_size       += nm->metadata_size();
 149     scopes_data_size    += nm->scopes_data_size();
 150     scopes_pcs_size     += nm->scopes_pcs_size();
 151     dependencies_size   += nm->dependencies_size();
 152     handler_table_size  += nm->handler_table_size();
 153     nul_chk_table_size  += nm->nul_chk_table_size();
 154 #if INCLUDE_JVMCI
 155     speculations_size   += nm->speculations_size();
 156     jvmci_data_size     += nm->jvmci_data_size();
 157 #endif
 158   }
 159   void print_nmethod_stats(const char* name) {
 160     if (nmethod_count == 0)  return;
 161     tty->print_cr("Statistics for %u bytecoded nmethods for %s:", nmethod_count, name);
 162     if (total_size != 0)          tty->print_cr(" total in heap  = %u", total_size);
 163     if (nmethod_count != 0)       tty->print_cr(" header         = " SIZE_FORMAT, nmethod_count * sizeof(nmethod));
 164     if (relocation_size != 0)     tty->print_cr(" relocation     = %u", relocation_size);
 165     if (consts_size != 0)         tty->print_cr(" constants      = %u", consts_size);
 166     if (insts_size != 0)          tty->print_cr(" main code      = %u", insts_size);
 167     if (stub_size != 0)           tty->print_cr(" stub code      = %u", stub_size);
 168     if (oops_size != 0)           tty->print_cr(" oops           = %u", oops_size);
 169     if (metadata_size != 0)       tty->print_cr(" metadata       = %u", metadata_size);
 170     if (scopes_data_size != 0)    tty->print_cr(" scopes data    = %u", scopes_data_size);
 171     if (scopes_pcs_size != 0)     tty->print_cr(" scopes pcs     = %u", scopes_pcs_size);
 172     if (dependencies_size != 0)   tty->print_cr(" dependencies   = %u", dependencies_size);
 173     if (handler_table_size != 0)  tty->print_cr(" handler table  = %u", handler_table_size);
 174     if (nul_chk_table_size != 0)  tty->print_cr(" nul chk table  = %u", nul_chk_table_size);
 175 #if INCLUDE_JVMCI
 176     if (speculations_size != 0)   tty->print_cr(" speculations   = %u", speculations_size);
 177     if (jvmci_data_size != 0)     tty->print_cr(" JVMCI data     = %u", jvmci_data_size);
 178 #endif
 179   }
 180 };
 181 
 182 struct native_nmethod_stats_struct {
 183   uint native_nmethod_count;
 184   uint native_total_size;
 185   uint native_relocation_size;
 186   uint native_insts_size;
 187   uint native_oops_size;
 188   uint native_metadata_size;
 189   void note_native_nmethod(nmethod* nm) {
 190     native_nmethod_count += 1;
 191     native_total_size       += nm->size();
 192     native_relocation_size  += nm->relocation_size();
 193     native_insts_size       += nm->insts_size();
 194     native_oops_size        += nm->oops_size();
 195     native_metadata_size    += nm->metadata_size();
 196   }
 197   void print_native_nmethod_stats() {
 198     if (native_nmethod_count == 0)  return;
 199     tty->print_cr("Statistics for %u native nmethods:", native_nmethod_count);
 200     if (native_total_size != 0)       tty->print_cr(" N. total size  = %u", native_total_size);
 201     if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %u", native_relocation_size);
 202     if (native_insts_size != 0)       tty->print_cr(" N. main code   = %u", native_insts_size);
 203     if (native_oops_size != 0)        tty->print_cr(" N. oops        = %u", native_oops_size);
 204     if (native_metadata_size != 0)    tty->print_cr(" N. metadata    = %u", native_metadata_size);
 205   }
 206 };
 207 
 208 struct pc_nmethod_stats_struct {
 209   uint pc_desc_resets;   // number of resets (= number of caches)
 210   uint pc_desc_queries;  // queries to nmethod::find_pc_desc
 211   uint pc_desc_approx;   // number of those which have approximate true
 212   uint pc_desc_repeats;  // number of _pc_descs[0] hits
 213   uint pc_desc_hits;     // number of LRU cache hits
 214   uint pc_desc_tests;    // total number of PcDesc examinations
 215   uint pc_desc_searches; // total number of quasi-binary search steps
 216   uint pc_desc_adds;     // number of LUR cache insertions
 217 
 218   void print_pc_stats() {
 219     tty->print_cr("PcDesc Statistics:  %u queries, %.2f comparisons per query",
 220                   pc_desc_queries,
 221                   (double)(pc_desc_tests + pc_desc_searches)
 222                   / pc_desc_queries);
 223     tty->print_cr("  caches=%d queries=%u/%u, hits=%u+%u, tests=%u+%u, adds=%u",
 224                   pc_desc_resets,
 225                   pc_desc_queries, pc_desc_approx,
 226                   pc_desc_repeats, pc_desc_hits,
 227                   pc_desc_tests, pc_desc_searches, pc_desc_adds);
 228   }
 229 };
 230 
 231 #ifdef COMPILER1
 232 static java_nmethod_stats_struct c1_java_nmethod_stats;
 233 #endif
 234 #ifdef COMPILER2
 235 static java_nmethod_stats_struct c2_java_nmethod_stats;
 236 #endif
 237 #if INCLUDE_JVMCI
 238 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
 239 #endif
 240 static java_nmethod_stats_struct unknown_java_nmethod_stats;
 241 
 242 static native_nmethod_stats_struct native_nmethod_stats;
 243 static pc_nmethod_stats_struct pc_nmethod_stats;
 244 
 245 static void note_java_nmethod(nmethod* nm) {
 246 #ifdef COMPILER1
 247   if (nm->is_compiled_by_c1()) {
 248     c1_java_nmethod_stats.note_nmethod(nm);
 249   } else
 250 #endif
 251 #ifdef COMPILER2
 252   if (nm->is_compiled_by_c2()) {
 253     c2_java_nmethod_stats.note_nmethod(nm);
 254   } else
 255 #endif
 256 #if INCLUDE_JVMCI
 257   if (nm->is_compiled_by_jvmci()) {
 258     jvmci_java_nmethod_stats.note_nmethod(nm);
 259   } else
 260 #endif
 261   {
 262     unknown_java_nmethod_stats.note_nmethod(nm);
 263   }
 264 }
 265 #endif // !PRODUCT
 266 
 267 //---------------------------------------------------------------------------------
 268 
 269 
 270 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
 271   assert(pc != nullptr, "Must be non null");
 272   assert(exception.not_null(), "Must be non null");
 273   assert(handler != nullptr, "Must be non null");
 274 
 275   _count = 0;
 276   _exception_type = exception->klass();
 277   _next = nullptr;
 278   _purge_list_next = nullptr;
 279 
 280   add_address_and_handler(pc,handler);
 281 }
 282 
 283 
 284 address ExceptionCache::match(Handle exception, address pc) {
 285   assert(pc != nullptr,"Must be non null");
 286   assert(exception.not_null(),"Must be non null");
 287   if (exception->klass() == exception_type()) {
 288     return (test_address(pc));
 289   }
 290 
 291   return nullptr;
 292 }
 293 
 294 
 295 bool ExceptionCache::match_exception_with_space(Handle exception) {
 296   assert(exception.not_null(),"Must be non null");
 297   if (exception->klass() == exception_type() && count() < cache_size) {
 298     return true;
 299   }
 300   return false;
 301 }
 302 
 303 
 304 address ExceptionCache::test_address(address addr) {
 305   int limit = count();
 306   for (int i = 0; i < limit; i++) {
 307     if (pc_at(i) == addr) {
 308       return handler_at(i);
 309     }
 310   }
 311   return nullptr;
 312 }
 313 
 314 
 315 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
 316   if (test_address(addr) == handler) return true;
 317 
 318   int index = count();
 319   if (index < cache_size) {
 320     set_pc_at(index, addr);
 321     set_handler_at(index, handler);
 322     increment_count();
 323     return true;
 324   }
 325   return false;
 326 }
 327 
 328 ExceptionCache* ExceptionCache::next() {
 329   return Atomic::load(&_next);
 330 }
 331 
 332 void ExceptionCache::set_next(ExceptionCache *ec) {
 333   Atomic::store(&_next, ec);
 334 }
 335 
 336 //-----------------------------------------------------------------------------
 337 
 338 
 339 // Helper used by both find_pc_desc methods.
 340 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
 341   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
 342   if (!approximate)
 343     return pc->pc_offset() == pc_offset;
 344   else
 345     return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
 346 }
 347 
 348 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
 349   if (initial_pc_desc == nullptr) {
 350     _pc_descs[0] = nullptr; // native method; no PcDescs at all
 351     return;
 352   }
 353   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_resets);
 354   // reset the cache by filling it with benign (non-null) values
 355   assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
 356   for (int i = 0; i < cache_size; i++)
 357     _pc_descs[i] = initial_pc_desc;
 358 }
 359 
 360 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
 361   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_queries);
 362   NOT_PRODUCT(if (approximate) ++pc_nmethod_stats.pc_desc_approx);
 363 
 364   // Note: one might think that caching the most recently
 365   // read value separately would be a win, but one would be
 366   // wrong.  When many threads are updating it, the cache
 367   // line it's in would bounce between caches, negating
 368   // any benefit.
 369 
 370   // In order to prevent race conditions do not load cache elements
 371   // repeatedly, but use a local copy:
 372   PcDesc* res;
 373 
 374   // Step one:  Check the most recently added value.
 375   res = _pc_descs[0];
 376   if (res == nullptr) return nullptr;  // native method; no PcDescs at all
 377   if (match_desc(res, pc_offset, approximate)) {
 378     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
 379     return res;
 380   }
 381 
 382   // Step two:  Check the rest of the LRU cache.
 383   for (int i = 1; i < cache_size; ++i) {
 384     res = _pc_descs[i];
 385     if (res->pc_offset() < 0) break;  // optimization: skip empty cache
 386     if (match_desc(res, pc_offset, approximate)) {
 387       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
 388       return res;
 389     }
 390   }
 391 
 392   // Report failure.
 393   return nullptr;
 394 }
 395 
 396 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
 397   MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, Thread::current());)
 398   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
 399   // Update the LRU cache by shifting pc_desc forward.
 400   for (int i = 0; i < cache_size; i++)  {
 401     PcDesc* next = _pc_descs[i];
 402     _pc_descs[i] = pc_desc;
 403     pc_desc = next;
 404   }
 405 }
 406 
 407 // adjust pcs_size so that it is a multiple of both oopSize and
 408 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
 409 // of oopSize, then 2*sizeof(PcDesc) is)
 410 static int adjust_pcs_size(int pcs_size) {
 411   int nsize = align_up(pcs_size,   oopSize);
 412   if ((nsize % sizeof(PcDesc)) != 0) {
 413     nsize = pcs_size + sizeof(PcDesc);
 414   }
 415   assert((nsize % oopSize) == 0, "correct alignment");
 416   return nsize;
 417 }
 418 
 419 
 420 int nmethod::total_size() const {
 421   return
 422     consts_size()        +
 423     insts_size()         +
 424     stub_size()          +
 425     scopes_data_size()   +
 426     scopes_pcs_size()    +
 427     handler_table_size() +
 428     nul_chk_table_size();
 429 }
 430 
 431 const char* nmethod::compile_kind() const {
 432   if (is_osr_method())     return "osr";
 433   if (method() != nullptr && is_native_method()) {
 434     if (method()->is_continuation_native_intrinsic()) {
 435       return "cnt";
 436     }
 437     return "c2n";
 438   }
 439   return nullptr;
 440 }
 441 
 442 // Fill in default values for various flag fields
 443 void nmethod::init_defaults() {
 444   _state                      = not_installed;
 445   _has_flushed_dependencies   = 0;
 446   _load_reported              = false; // jvmti state
 447 
 448   _oops_do_mark_link       = nullptr;
 449   _osr_link                = nullptr;
 450 #if INCLUDE_RTM_OPT
 451   _rtm_state               = NoRTM;
 452 #endif
 453 }
 454 
 455 #ifdef ASSERT
 456 class CheckForOopsClosure : public OopClosure {
 457   bool _found_oop = false;
 458  public:
 459   virtual void do_oop(oop* o) { _found_oop = true; }
 460   virtual void do_oop(narrowOop* o) { _found_oop = true; }
 461   bool found_oop() { return _found_oop; }
 462 };
 463 class CheckForMetadataClosure : public MetadataClosure {
 464   bool _found_metadata = false;
 465   Metadata* _ignore = nullptr;
 466  public:
 467   CheckForMetadataClosure(Metadata* ignore) : _ignore(ignore) {}
 468   virtual void do_metadata(Metadata* md) { if (md != _ignore) _found_metadata = true; }
 469   bool found_metadata() { return _found_metadata; }
 470 };
 471 
 472 static void assert_no_oops_or_metadata(nmethod* nm) {
 473   if (nm == nullptr) return;
 474   assert(nm->oop_maps() == nullptr, "expectation");
 475 
 476   CheckForOopsClosure cfo;
 477   nm->oops_do(&cfo);
 478   assert(!cfo.found_oop(), "no oops allowed");
 479 
 480   // We allow an exception for the own Method, but require its class to be permanent.
 481   Method* own_method = nm->method();
 482   CheckForMetadataClosure cfm(/* ignore reference to own Method */ own_method);
 483   nm->metadata_do(&cfm);
 484   assert(!cfm.found_metadata(), "no metadata allowed");
 485 
 486   assert(own_method->method_holder()->class_loader_data()->is_permanent_class_loader_data(),
 487          "Method's class needs to be permanent");
 488 }
 489 #endif
 490 
 491 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
 492   int compile_id,
 493   CodeBuffer *code_buffer,
 494   int vep_offset,
 495   int frame_complete,
 496   int frame_size,
 497   ByteSize basic_lock_owner_sp_offset,
 498   ByteSize basic_lock_sp_offset,
 499   OopMapSet* oop_maps,
 500   int exception_handler) {
 501   code_buffer->finalize_oop_references(method);
 502   // create nmethod
 503   nmethod* nm = nullptr;
 504   int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
 505   {
 506     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 507 
 508     CodeOffsets offsets;
 509     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
 510     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
 511     if (exception_handler != -1) {
 512       offsets.set_value(CodeOffsets::Exceptions, exception_handler);
 513     }
 514 
 515     // MH intrinsics are dispatch stubs which are compatible with NonNMethod space.
 516     // IsUnloadingBehaviour::is_unloading needs to handle them separately.
 517     bool allow_NonNMethod_space = method->can_be_allocated_in_NonNMethod_space();
 518     nm = new (native_nmethod_size, allow_NonNMethod_space)
 519     nmethod(method(), compiler_none, native_nmethod_size,
 520             compile_id, &offsets,
 521             code_buffer, frame_size,
 522             basic_lock_owner_sp_offset,
 523             basic_lock_sp_offset,
 524             oop_maps);
 525     DEBUG_ONLY( if (allow_NonNMethod_space) assert_no_oops_or_metadata(nm); )
 526     NOT_PRODUCT(if (nm != nullptr) native_nmethod_stats.note_native_nmethod(nm));
 527   }
 528 
 529   if (nm != nullptr) {
 530     // verify nmethod
 531     debug_only(nm->verify();) // might block
 532 
 533     nm->log_new_nmethod();
 534   }
 535   return nm;
 536 }
 537 
 538 nmethod* nmethod::new_nmethod(const methodHandle& method,
 539   int compile_id,
 540   int entry_bci,
 541   CodeOffsets* offsets,
 542   int orig_pc_offset,
 543   DebugInformationRecorder* debug_info,
 544   Dependencies* dependencies,
 545   CodeBuffer* code_buffer, int frame_size,
 546   OopMapSet* oop_maps,
 547   ExceptionHandlerTable* handler_table,
 548   ImplicitExceptionTable* nul_chk_table,
 549   AbstractCompiler* compiler,
 550   CompLevel comp_level
 551 #if INCLUDE_JVMCI
 552   , char* speculations,
 553   int speculations_len,
 554   JVMCINMethodData* jvmci_data
 555 #endif
 556 )
 557 {
 558   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 559   code_buffer->finalize_oop_references(method);
 560   // create nmethod
 561   nmethod* nm = nullptr;
 562 #if INCLUDE_JVMCI
 563   int jvmci_data_size = compiler->is_jvmci() ? jvmci_data->size() : 0;
 564 #endif
 565   int nmethod_size =
 566     CodeBlob::allocation_size(code_buffer, sizeof(nmethod))
 567     + adjust_pcs_size(debug_info->pcs_size())
 568     + align_up((int)dependencies->size_in_bytes(), oopSize)
 569     + align_up(handler_table->size_in_bytes()    , oopSize)
 570     + align_up(nul_chk_table->size_in_bytes()    , oopSize)
 571 #if INCLUDE_JVMCI
 572     + align_up(speculations_len                  , oopSize)
 573     + align_up(jvmci_data_size                   , oopSize)
 574 #endif
 575     + align_up(debug_info->data_size()           , oopSize);
 576   {
 577     MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 578 
 579     nm = new (nmethod_size, comp_level)
 580     nmethod(method(), compiler->type(), nmethod_size, compile_id, entry_bci, offsets,
 581             orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
 582             oop_maps,
 583             handler_table,
 584             nul_chk_table,
 585             compiler,
 586             comp_level
 587 #if INCLUDE_JVMCI
 588             , speculations,
 589             speculations_len,
 590             jvmci_data
 591 #endif
 592             );
 593 
 594     if (nm != nullptr) {
 595       // To make dependency checking during class loading fast, record
 596       // the nmethod dependencies in the classes it is dependent on.
 597       // This allows the dependency checking code to simply walk the
 598       // class hierarchy above the loaded class, checking only nmethods
 599       // which are dependent on those classes.  The slow way is to
 600       // check every nmethod for dependencies which makes it linear in
 601       // the number of methods compiled.  For applications with a lot
 602       // classes the slow way is too slow.
 603       for (Dependencies::DepStream deps(nm); deps.next(); ) {
 604         if (deps.type() == Dependencies::call_site_target_value) {
 605           // CallSite dependencies are managed on per-CallSite instance basis.
 606           oop call_site = deps.argument_oop(0);
 607           MethodHandles::add_dependent_nmethod(call_site, nm);
 608         } else {
 609           InstanceKlass* ik = deps.context_type();
 610           if (ik == nullptr) {
 611             continue;  // ignore things like evol_method
 612           }
 613           // record this nmethod as dependent on this klass
 614           ik->add_dependent_nmethod(nm);
 615         }
 616       }
 617       NOT_PRODUCT(if (nm != nullptr)  note_java_nmethod(nm));
 618     }
 619   }
 620   // Do verification and logging outside CodeCache_lock.
 621   if (nm != nullptr) {
 622     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
 623     DEBUG_ONLY(nm->verify();)
 624     nm->log_new_nmethod();
 625   }
 626   return nm;
 627 }
 628 
 629 // For native wrappers
 630 nmethod::nmethod(
 631   Method* method,
 632   CompilerType type,
 633   int nmethod_size,
 634   int compile_id,
 635   CodeOffsets* offsets,
 636   CodeBuffer* code_buffer,
 637   int frame_size,
 638   ByteSize basic_lock_owner_sp_offset,
 639   ByteSize basic_lock_sp_offset,
 640   OopMapSet* oop_maps )
 641   : CompiledMethod(method, "native nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, true),
 642   _unlinked_next(nullptr),
 643   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
 644   _native_basic_lock_sp_offset(basic_lock_sp_offset),
 645   _is_unloading_state(0)
 646 {
 647   {
 648     int scopes_data_offset   = 0;
 649     int deoptimize_offset    = 0;
 650     int deoptimize_mh_offset = 0;
 651 
 652     debug_only(NoSafepointVerifier nsv;)
 653     assert_locked_or_safepoint(CodeCache_lock);
 654 
 655     init_defaults();
 656     _comp_level              = CompLevel_none;
 657     _entry_bci               = InvocationEntryBci;
 658     // We have no exception handler or deopt handler make the
 659     // values something that will never match a pc like the nmethod vtable entry
 660     _exception_offset        = 0;
 661     _orig_pc_offset          = 0;
 662     _gc_epoch                = CodeCache::gc_epoch();
 663 
 664     _consts_offset           = content_offset()      + code_buffer->total_offset_of(code_buffer->consts());
 665     _stub_offset             = content_offset()      + code_buffer->total_offset_of(code_buffer->stubs());
 666     _oops_offset             = data_offset();
 667     _metadata_offset         = _oops_offset          + align_up(code_buffer->total_oop_size(), oopSize);
 668     scopes_data_offset       = _metadata_offset      + align_up(code_buffer->total_metadata_size(), wordSize);
 669     _scopes_pcs_offset       = scopes_data_offset;
 670     _dependencies_offset     = _scopes_pcs_offset;
 671     _handler_table_offset    = _dependencies_offset;
 672     _nul_chk_table_offset    = _handler_table_offset;
 673     _skipped_instructions_size = code_buffer->total_skipped_instructions_size();
 674 #if INCLUDE_JVMCI
 675     _speculations_offset     = _nul_chk_table_offset;
 676     _jvmci_data_offset       = _speculations_offset;
 677     _nmethod_end_offset      = _jvmci_data_offset;
 678 #else
 679     _nmethod_end_offset      = _nul_chk_table_offset;
 680 #endif
 681     _compile_id              = compile_id;
 682     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 683     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 684 
 685     assert(!method->has_scalarized_args(), "scalarized native wrappers not supported yet"); // for the next 3 fields
 686     _inline_entry_point       = _entry_point;
 687     _verified_inline_entry_point = _verified_entry_point;
 688     _verified_inline_ro_entry_point = _verified_entry_point;
 689 
 690     _osr_entry_point         = nullptr;
 691     _exception_cache         = nullptr;
 692     _pc_desc_container.reset_to(nullptr);
 693 
 694     _exception_offset        = code_offset()         + offsets->value(CodeOffsets::Exceptions);
 695 
 696     _scopes_data_begin = (address) this + scopes_data_offset;
 697     _deopt_handler_begin = (address) this + deoptimize_offset;
 698     _deopt_mh_handler_begin = (address) this + deoptimize_mh_offset;
 699 
 700     code_buffer->copy_code_and_locs_to(this);
 701     code_buffer->copy_values_to(this);
 702 
 703     clear_unloading_state();
 704 
 705     Universe::heap()->register_nmethod(this);
 706     debug_only(Universe::heap()->verify_nmethod(this));
 707 
 708     CodeCache::commit(this);
 709 
 710     finalize_relocations();
 711   }
 712 
 713   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
 714     ttyLocker ttyl;  // keep the following output all in one block
 715     // This output goes directly to the tty, not the compiler log.
 716     // To enable tools to match it up with the compilation activity,
 717     // be sure to tag this tty output with the compile ID.
 718     if (xtty != nullptr) {
 719       xtty->begin_head("print_native_nmethod");
 720       xtty->method(_method);
 721       xtty->stamp();
 722       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
 723     }
 724     // Print the header part, then print the requested information.
 725     // This is both handled in decode2(), called via print_code() -> decode()
 726     if (PrintNativeNMethods) {
 727       tty->print_cr("-------------------------- Assembly (native nmethod) ---------------------------");
 728       print_code();
 729       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
 730 #if defined(SUPPORT_DATA_STRUCTS)
 731       if (AbstractDisassembler::show_structs()) {
 732         if (oop_maps != nullptr) {
 733           tty->print("oop maps:"); // oop_maps->print_on(tty) outputs a cr() at the beginning
 734           oop_maps->print_on(tty);
 735           tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
 736         }
 737       }
 738 #endif
 739     } else {
 740       print(); // print the header part only.
 741     }
 742 #if defined(SUPPORT_DATA_STRUCTS)
 743     if (AbstractDisassembler::show_structs()) {
 744       if (PrintRelocations) {
 745         print_relocations();
 746         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
 747       }
 748     }
 749 #endif
 750     if (xtty != nullptr) {
 751       xtty->tail("print_native_nmethod");
 752     }
 753   }
 754 }
 755 
 756 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
 757   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
 758 }
 759 
 760 void* nmethod::operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw () {
 761   // Try MethodNonProfiled and MethodProfiled.
 762   void* return_value = CodeCache::allocate(nmethod_size, CodeBlobType::MethodNonProfiled);
 763   if (return_value != nullptr || !allow_NonNMethod_space) return return_value;
 764   // Try NonNMethod or give up.
 765   return CodeCache::allocate(nmethod_size, CodeBlobType::NonNMethod);
 766 }
 767 
 768 nmethod::nmethod(
 769   Method* method,
 770   CompilerType type,
 771   int nmethod_size,
 772   int compile_id,
 773   int entry_bci,
 774   CodeOffsets* offsets,
 775   int orig_pc_offset,
 776   DebugInformationRecorder* debug_info,
 777   Dependencies* dependencies,
 778   CodeBuffer *code_buffer,
 779   int frame_size,
 780   OopMapSet* oop_maps,
 781   ExceptionHandlerTable* handler_table,
 782   ImplicitExceptionTable* nul_chk_table,
 783   AbstractCompiler* compiler,
 784   CompLevel comp_level
 785 #if INCLUDE_JVMCI
 786   , char* speculations,
 787   int speculations_len,
 788   JVMCINMethodData* jvmci_data
 789 #endif
 790   )
 791   : CompiledMethod(method, "nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, true),
 792   _unlinked_next(nullptr),
 793   _native_receiver_sp_offset(in_ByteSize(-1)),
 794   _native_basic_lock_sp_offset(in_ByteSize(-1)),
 795   _is_unloading_state(0)
 796 {
 797   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 798   {
 799     debug_only(NoSafepointVerifier nsv;)
 800     assert_locked_or_safepoint(CodeCache_lock);
 801 
 802     _deopt_handler_begin = (address) this;
 803     _deopt_mh_handler_begin = (address) this;
 804 
 805     init_defaults();
 806     _entry_bci               = entry_bci;
 807     _compile_id              = compile_id;
 808     _comp_level              = comp_level;
 809     _orig_pc_offset          = orig_pc_offset;
 810     _gc_epoch                = CodeCache::gc_epoch();
 811 
 812     // Section offsets
 813     _consts_offset           = content_offset()      + code_buffer->total_offset_of(code_buffer->consts());
 814     _stub_offset             = content_offset()      + code_buffer->total_offset_of(code_buffer->stubs());
 815     set_ctable_begin(header_begin() + _consts_offset);
 816     _skipped_instructions_size      = code_buffer->total_skipped_instructions_size();
 817 
 818 #if INCLUDE_JVMCI
 819     if (compiler->is_jvmci()) {
 820       // JVMCI might not produce any stub sections
 821       if (offsets->value(CodeOffsets::Exceptions) != -1) {
 822         _exception_offset        = code_offset()          + offsets->value(CodeOffsets::Exceptions);
 823       } else {
 824         _exception_offset = -1;
 825       }
 826       if (offsets->value(CodeOffsets::Deopt) != -1) {
 827         _deopt_handler_begin       = (address) this + code_offset()          + offsets->value(CodeOffsets::Deopt);
 828       } else {
 829         _deopt_handler_begin = nullptr;
 830       }
 831       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 832         _deopt_mh_handler_begin  = (address) this + code_offset()          + offsets->value(CodeOffsets::DeoptMH);
 833       } else {
 834         _deopt_mh_handler_begin = nullptr;
 835       }
 836     } else
 837 #endif
 838     {
 839       // Exception handler and deopt handler are in the stub section
 840       assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
 841       assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
 842 
 843       _exception_offset       = _stub_offset          + offsets->value(CodeOffsets::Exceptions);
 844       _deopt_handler_begin    = (address) this + _stub_offset          + offsets->value(CodeOffsets::Deopt);
 845       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 846         _deopt_mh_handler_begin  = (address) this + _stub_offset          + offsets->value(CodeOffsets::DeoptMH);
 847       } else {
 848         _deopt_mh_handler_begin  = nullptr;
 849       }
 850     }
 851     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
 852       _unwind_handler_offset = code_offset()         + offsets->value(CodeOffsets::UnwindHandler);
 853     } else {
 854       _unwind_handler_offset = -1;
 855     }
 856 
 857     _oops_offset             = data_offset();
 858     _metadata_offset         = _oops_offset          + align_up(code_buffer->total_oop_size(), oopSize);
 859     int scopes_data_offset   = _metadata_offset      + align_up(code_buffer->total_metadata_size(), wordSize);
 860 
 861     _scopes_pcs_offset       = scopes_data_offset    + align_up(debug_info->data_size       (), oopSize);
 862     _dependencies_offset     = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
 863     _handler_table_offset    = _dependencies_offset  + align_up((int)dependencies->size_in_bytes(), oopSize);
 864     _nul_chk_table_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
 865 #if INCLUDE_JVMCI
 866     _speculations_offset     = _nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize);
 867     _jvmci_data_offset       = _speculations_offset  + align_up(speculations_len, oopSize);
 868     int jvmci_data_size      = compiler->is_jvmci() ? jvmci_data->size() : 0;
 869     _nmethod_end_offset      = _jvmci_data_offset    + align_up(jvmci_data_size, oopSize);
 870 #else
 871     _nmethod_end_offset      = _nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize);
 872 #endif
 873     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 874     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 875     _inline_entry_point       = code_begin()         + offsets->value(CodeOffsets::Inline_Entry);
 876     _verified_inline_entry_point = code_begin()      + offsets->value(CodeOffsets::Verified_Inline_Entry);
 877     _verified_inline_ro_entry_point = code_begin()   + offsets->value(CodeOffsets::Verified_Inline_Entry_RO);
 878     _osr_entry_point         = code_begin()          + offsets->value(CodeOffsets::OSR_Entry);
 879     _exception_cache         = nullptr;
 880     _scopes_data_begin       = (address) this + scopes_data_offset;
 881 
 882     _pc_desc_container.reset_to(scopes_pcs_begin());
 883 
 884     code_buffer->copy_code_and_locs_to(this);
 885     // Copy contents of ScopeDescRecorder to nmethod
 886     code_buffer->copy_values_to(this);
 887     debug_info->copy_to(this);
 888     dependencies->copy_to(this);
 889     clear_unloading_state();
 890 
 891 #if INCLUDE_JVMCI
 892     if (compiler->is_jvmci()) {
 893       // Initialize the JVMCINMethodData object inlined into nm
 894       jvmci_nmethod_data()->copy(jvmci_data);
 895     }
 896 #endif
 897 
 898     Universe::heap()->register_nmethod(this);
 899     debug_only(Universe::heap()->verify_nmethod(this));
 900 
 901     CodeCache::commit(this);
 902 
 903     finalize_relocations();
 904 
 905     // Copy contents of ExceptionHandlerTable to nmethod
 906     handler_table->copy_to(this);
 907     nul_chk_table->copy_to(this);
 908 
 909 #if INCLUDE_JVMCI
 910     // Copy speculations to nmethod
 911     if (speculations_size() != 0) {
 912       memcpy(speculations_begin(), speculations, speculations_len);
 913     }
 914 #endif
 915 
 916     // we use the information of entry points to find out if a method is
 917     // static or non static
 918     assert(compiler->is_c2() || compiler->is_jvmci() ||
 919            _method->is_static() == (entry_point() == _verified_entry_point),
 920            " entry points must be same for static methods and vice versa");
 921   }
 922 }
 923 
 924 // Print a short set of xml attributes to identify this nmethod.  The
 925 // output should be embedded in some other element.
 926 void nmethod::log_identity(xmlStream* log) const {
 927   log->print(" compile_id='%d'", compile_id());
 928   const char* nm_kind = compile_kind();
 929   if (nm_kind != nullptr)  log->print(" compile_kind='%s'", nm_kind);
 930   log->print(" compiler='%s'", compiler_name());
 931   if (TieredCompilation) {
 932     log->print(" level='%d'", comp_level());
 933   }
 934 #if INCLUDE_JVMCI
 935   if (jvmci_nmethod_data() != nullptr) {
 936     const char* jvmci_name = jvmci_nmethod_data()->name();
 937     if (jvmci_name != nullptr) {
 938       log->print(" jvmci_mirror_name='");
 939       log->text("%s", jvmci_name);
 940       log->print("'");
 941     }
 942   }
 943 #endif
 944 }
 945 
 946 
 947 #define LOG_OFFSET(log, name)                    \
 948   if (p2i(name##_end()) - p2i(name##_begin())) \
 949     log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'"    , \
 950                p2i(name##_begin()) - p2i(this))
 951 
 952 
 953 void nmethod::log_new_nmethod() const {
 954   if (LogCompilation && xtty != nullptr) {
 955     ttyLocker ttyl;
 956     xtty->begin_elem("nmethod");
 957     log_identity(xtty);
 958     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
 959     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
 960 
 961     LOG_OFFSET(xtty, relocation);
 962     LOG_OFFSET(xtty, consts);
 963     LOG_OFFSET(xtty, insts);
 964     LOG_OFFSET(xtty, stub);
 965     LOG_OFFSET(xtty, scopes_data);
 966     LOG_OFFSET(xtty, scopes_pcs);
 967     LOG_OFFSET(xtty, dependencies);
 968     LOG_OFFSET(xtty, handler_table);
 969     LOG_OFFSET(xtty, nul_chk_table);
 970     LOG_OFFSET(xtty, oops);
 971     LOG_OFFSET(xtty, metadata);
 972 
 973     xtty->method(method());
 974     xtty->stamp();
 975     xtty->end_elem();
 976   }
 977 }
 978 
 979 #undef LOG_OFFSET
 980 
 981 
 982 // Print out more verbose output usually for a newly created nmethod.
 983 void nmethod::print_on(outputStream* st, const char* msg) const {
 984   if (st != nullptr) {
 985     ttyLocker ttyl;
 986     if (WizardMode) {
 987       CompileTask::print(st, this, msg, /*short_form:*/ true);
 988       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
 989     } else {
 990       CompileTask::print(st, this, msg, /*short_form:*/ false);
 991     }
 992   }
 993 }
 994 
 995 void nmethod::maybe_print_nmethod(const DirectiveSet* directive) {
 996   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
 997   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
 998     print_nmethod(printnmethods);
 999   }
1000 }
1001 
1002 void nmethod::print_nmethod(bool printmethod) {
1003   ttyLocker ttyl;  // keep the following output all in one block
1004   if (xtty != nullptr) {
1005     xtty->begin_head("print_nmethod");
1006     log_identity(xtty);
1007     xtty->stamp();
1008     xtty->end_head();
1009   }
1010   // Print the header part, then print the requested information.
1011   // This is both handled in decode2().
1012   if (printmethod) {
1013     ResourceMark m;
1014     if (is_compiled_by_c1()) {
1015       tty->cr();
1016       tty->print_cr("============================= C1-compiled nmethod ==============================");
1017     }
1018     if (is_compiled_by_jvmci()) {
1019       tty->cr();
1020       tty->print_cr("=========================== JVMCI-compiled nmethod =============================");
1021     }
1022     tty->print_cr("----------------------------------- Assembly -----------------------------------");
1023     decode2(tty);
1024 #if defined(SUPPORT_DATA_STRUCTS)
1025     if (AbstractDisassembler::show_structs()) {
1026       // Print the oops from the underlying CodeBlob as well.
1027       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1028       print_oops(tty);
1029       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1030       print_metadata(tty);
1031       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1032       print_pcs();
1033       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1034       if (oop_maps() != nullptr) {
1035         tty->print("oop maps:"); // oop_maps()->print_on(tty) outputs a cr() at the beginning
1036         oop_maps()->print_on(tty);
1037         tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1038       }
1039     }
1040 #endif
1041   } else {
1042     print(); // print the header part only.
1043   }
1044 
1045 #if defined(SUPPORT_DATA_STRUCTS)
1046   if (AbstractDisassembler::show_structs()) {
1047     methodHandle mh(Thread::current(), _method);
1048     if (printmethod || PrintDebugInfo || CompilerOracle::has_option(mh, CompileCommand::PrintDebugInfo)) {
1049       print_scopes();
1050       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1051     }
1052     if (printmethod || PrintRelocations || CompilerOracle::has_option(mh, CompileCommand::PrintRelocations)) {
1053       print_relocations();
1054       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1055     }
1056     if (printmethod || PrintDependencies || CompilerOracle::has_option(mh, CompileCommand::PrintDependencies)) {
1057       print_dependencies_on(tty);
1058       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1059     }
1060     if (printmethod || PrintExceptionHandlers) {
1061       print_handler_table();
1062       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1063       print_nul_chk_table();
1064       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1065     }
1066 
1067     if (printmethod) {
1068       print_recorded_oops();
1069       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1070       print_recorded_metadata();
1071       tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1072     }
1073   }
1074 #endif
1075 
1076   if (xtty != nullptr) {
1077     xtty->tail("print_nmethod");
1078   }
1079 }
1080 
1081 
1082 // Promote one word from an assembly-time handle to a live embedded oop.
1083 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1084   if (handle == nullptr ||
1085       // As a special case, IC oops are initialized to 1 or -1.
1086       handle == (jobject) Universe::non_oop_word()) {
1087     *(void**)dest = handle;
1088   } else {
1089     *dest = JNIHandles::resolve_non_null(handle);
1090   }
1091 }
1092 
1093 
1094 // Have to have the same name because it's called by a template
1095 void nmethod::copy_values(GrowableArray<jobject>* array) {
1096   int length = array->length();
1097   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1098   oop* dest = oops_begin();
1099   for (int index = 0 ; index < length; index++) {
1100     initialize_immediate_oop(&dest[index], array->at(index));
1101   }
1102 
1103   // Now we can fix up all the oops in the code.  We need to do this
1104   // in the code because the assembler uses jobjects as placeholders.
1105   // The code and relocations have already been initialized by the
1106   // CodeBlob constructor, so it is valid even at this early point to
1107   // iterate over relocations and patch the code.
1108   fix_oop_relocations(nullptr, nullptr, /*initialize_immediates=*/ true);
1109 }
1110 
1111 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1112   int length = array->length();
1113   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1114   Metadata** dest = metadata_begin();
1115   for (int index = 0 ; index < length; index++) {
1116     dest[index] = array->at(index);
1117   }
1118 }
1119 
1120 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1121   // re-patch all oop-bearing instructions, just in case some oops moved
1122   RelocIterator iter(this, begin, end);
1123   while (iter.next()) {
1124     if (iter.type() == relocInfo::oop_type) {
1125       oop_Relocation* reloc = iter.oop_reloc();
1126       if (initialize_immediates && reloc->oop_is_immediate()) {
1127         oop* dest = reloc->oop_addr();
1128         jobject obj = *reinterpret_cast<jobject*>(dest);
1129         initialize_immediate_oop(dest, obj);
1130       }
1131       // Refresh the oop-related bits of this instruction.
1132       reloc->fix_oop_relocation();
1133     } else if (iter.type() == relocInfo::metadata_type) {
1134       metadata_Relocation* reloc = iter.metadata_reloc();
1135       reloc->fix_metadata_relocation();
1136     }
1137   }
1138 }
1139 
1140 static void install_post_call_nop_displacement(nmethod* nm, address pc) {
1141   NativePostCallNop* nop = nativePostCallNop_at((address) pc);
1142   intptr_t cbaddr = (intptr_t) nm;
1143   intptr_t offset = ((intptr_t) pc) - cbaddr;
1144 
1145   int oopmap_slot = nm->oop_maps()->find_slot_for_offset(int((intptr_t) pc - (intptr_t) nm->code_begin()));
1146   if (oopmap_slot < 0) { // this can happen at asynchronous (non-safepoint) stackwalks
1147     log_debug(codecache)("failed to find oopmap for cb: " INTPTR_FORMAT " offset: %d", cbaddr, (int) offset);
1148   } else if (((oopmap_slot & 0xff) == oopmap_slot) && ((offset & 0xffffff) == offset)) {
1149     jint value = (oopmap_slot << 24) | (jint) offset;
1150     nop->patch(value);
1151   } else {
1152     log_debug(codecache)("failed to encode %d %d", oopmap_slot, (int) offset);
1153   }
1154 }
1155 
1156 void nmethod::finalize_relocations() {
1157   NoSafepointVerifier nsv;
1158 
1159   // Make sure that post call nops fill in nmethod offsets eagerly so
1160   // we don't have to race with deoptimization
1161   RelocIterator iter(this);
1162   while (iter.next()) {
1163     if (iter.type() == relocInfo::post_call_nop_type) {
1164       post_call_nop_Relocation* const reloc = iter.post_call_nop_reloc();
1165       address pc = reloc->addr();
1166       install_post_call_nop_displacement(this, pc);
1167     }
1168   }
1169 }
1170 
1171 void nmethod::make_deoptimized() {
1172   if (!Continuations::enabled()) {
1173     // Don't deopt this again.
1174     set_deoptimized_done();
1175     return;
1176   }
1177 
1178   assert(method() == nullptr || can_be_deoptimized(), "");
1179 
1180   CompiledICLocker ml(this);
1181   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1182 
1183   // If post call nops have been already patched, we can just bail-out.
1184   if (has_been_deoptimized()) {
1185     return;
1186   }
1187 
1188   ResourceMark rm;
1189   RelocIterator iter(this, oops_reloc_begin());
1190 
1191   while (iter.next()) {
1192 
1193     switch (iter.type()) {
1194       case relocInfo::virtual_call_type:
1195       case relocInfo::opt_virtual_call_type: {
1196         CompiledIC *ic = CompiledIC_at(&iter);
1197         address pc = ic->end_of_call();
1198         NativePostCallNop* nop = nativePostCallNop_at(pc);
1199         if (nop != nullptr) {
1200           nop->make_deopt();
1201         }
1202         assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
1203         break;
1204       }
1205       case relocInfo::static_call_type: {
1206         CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1207         address pc = csc->end_of_call();
1208         NativePostCallNop* nop = nativePostCallNop_at(pc);
1209         //tty->print_cr(" - static pc %p", pc);
1210         if (nop != nullptr) {
1211           nop->make_deopt();
1212         }
1213         // We can't assert here, there are some calls to stubs / runtime
1214         // that have reloc data and doesn't have a post call NOP.
1215         //assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
1216         break;
1217       }
1218       default:
1219         break;
1220     }
1221   }
1222   // Don't deopt this again.
1223   set_deoptimized_done();
1224 }
1225 
1226 void nmethod::verify_clean_inline_caches() {
1227   assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1228 
1229   ResourceMark rm;
1230   RelocIterator iter(this, oops_reloc_begin());
1231   while(iter.next()) {
1232     switch(iter.type()) {
1233       case relocInfo::virtual_call_type:
1234       case relocInfo::opt_virtual_call_type: {
1235         CompiledIC *ic = CompiledIC_at(&iter);
1236         CodeBlob *cb = CodeCache::find_blob(ic->ic_destination());
1237         assert(cb != nullptr, "destination not in CodeBlob?");
1238         nmethod* nm = cb->as_nmethod_or_null();
1239         if( nm != nullptr ) {
1240           // Verify that inline caches pointing to bad nmethods are clean
1241           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1242             assert(ic->is_clean(), "IC should be clean");
1243           }
1244         }
1245         break;
1246       }
1247       case relocInfo::static_call_type: {
1248         CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1249         CodeBlob *cb = CodeCache::find_blob(csc->destination());
1250         assert(cb != nullptr, "destination not in CodeBlob?");
1251         nmethod* nm = cb->as_nmethod_or_null();
1252         if( nm != nullptr ) {
1253           // Verify that inline caches pointing to bad nmethods are clean
1254           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1255             assert(csc->is_clean(), "IC should be clean");
1256           }
1257         }
1258         break;
1259       }
1260       default:
1261         break;
1262     }
1263   }
1264 }
1265 
1266 void nmethod::mark_as_maybe_on_stack() {
1267   Atomic::store(&_gc_epoch, CodeCache::gc_epoch());
1268 }
1269 
1270 bool nmethod::is_maybe_on_stack() {
1271   // If the condition below is true, it means that the nmethod was found to
1272   // be alive the previous completed marking cycle.
1273   return Atomic::load(&_gc_epoch) >= CodeCache::previous_completed_gc_marking_cycle();
1274 }
1275 
1276 void nmethod::inc_decompile_count() {
1277   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1278   // Could be gated by ProfileTraps, but do not bother...
1279   Method* m = method();
1280   if (m == nullptr)  return;
1281   MethodData* mdo = m->method_data();
1282   if (mdo == nullptr)  return;
1283   // There is a benign race here.  See comments in methodData.hpp.
1284   mdo->inc_decompile_count();
1285 }
1286 
1287 bool nmethod::try_transition(signed char new_state_int) {
1288   signed char new_state = new_state_int;
1289   assert_lock_strong(CompiledMethod_lock);
1290   signed char old_state = _state;
1291   if (old_state >= new_state) {
1292     // Ensure monotonicity of transitions.
1293     return false;
1294   }
1295   Atomic::store(&_state, new_state);
1296   return true;
1297 }
1298 
1299 void nmethod::invalidate_osr_method() {
1300   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1301   // Remove from list of active nmethods
1302   if (method() != nullptr) {
1303     method()->method_holder()->remove_osr_nmethod(this);
1304   }
1305 }
1306 
1307 void nmethod::log_state_change() const {
1308   if (LogCompilation) {
1309     if (xtty != nullptr) {
1310       ttyLocker ttyl;  // keep the following output all in one block
1311       xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'",
1312                        os::current_thread_id());
1313       log_identity(xtty);
1314       xtty->stamp();
1315       xtty->end_elem();
1316     }
1317   }
1318 
1319   CompileTask::print_ul(this, "made not entrant");
1320   if (PrintCompilation) {
1321     print_on(tty, "made not entrant");
1322   }
1323 }
1324 
1325 void nmethod::unlink_from_method() {
1326   if (method() != nullptr) {
1327     method()->unlink_code(this);
1328   }
1329 }
1330 
1331 // Invalidate code
1332 bool nmethod::make_not_entrant() {
1333   // This can be called while the system is already at a safepoint which is ok
1334   NoSafepointVerifier nsv;
1335 
1336   if (is_unloading()) {
1337     // If the nmethod is unloading, then it is already not entrant through
1338     // the nmethod entry barriers. No need to do anything; GC will unload it.
1339     return false;
1340   }
1341 
1342   if (Atomic::load(&_state) == not_entrant) {
1343     // Avoid taking the lock if already in required state.
1344     // This is safe from races because the state is an end-state,
1345     // which the nmethod cannot back out of once entered.
1346     // No need for fencing either.
1347     return false;
1348   }
1349 
1350   {
1351     // Enter critical section.  Does not block for safepoint.
1352     ConditionalMutexLocker ml(CompiledMethod_lock, !CompiledMethod_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1353 
1354     if (Atomic::load(&_state) == not_entrant) {
1355       // another thread already performed this transition so nothing
1356       // to do, but return false to indicate this.
1357       return false;
1358     }
1359 
1360     if (is_osr_method()) {
1361       // This logic is equivalent to the logic below for patching the
1362       // verified entry point of regular methods.
1363       // this effectively makes the osr nmethod not entrant
1364       invalidate_osr_method();
1365     } else {
1366       // The caller can be calling the method statically or through an inline
1367       // cache call.
1368       NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1369                                        SharedRuntime::get_handle_wrong_method_stub());
1370     }
1371 
1372     if (update_recompile_counts()) {
1373       // Mark the method as decompiled.
1374       inc_decompile_count();
1375     }
1376 
1377     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
1378     if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
1379       // If nmethod entry barriers are not supported, we won't mark
1380       // nmethods as on-stack when they become on-stack. So we
1381       // degrade to a less accurate flushing strategy, for now.
1382       mark_as_maybe_on_stack();
1383     }
1384 
1385     // Change state
1386     bool success = try_transition(not_entrant);
1387     assert(success, "Transition can't fail");
1388 
1389     // Log the transition once
1390     log_state_change();
1391 
1392     // Remove nmethod from method.
1393     unlink_from_method();
1394 
1395   } // leave critical region under CompiledMethod_lock
1396 
1397 #if INCLUDE_JVMCI
1398   // Invalidate can't occur while holding the Patching lock
1399   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
1400   if (nmethod_data != nullptr) {
1401     nmethod_data->invalidate_nmethod_mirror(this);
1402   }
1403 #endif
1404 
1405 #ifdef ASSERT
1406   if (is_osr_method() && method() != nullptr) {
1407     // Make sure osr nmethod is invalidated, i.e. not on the list
1408     bool found = method()->method_holder()->remove_osr_nmethod(this);
1409     assert(!found, "osr nmethod should have been invalidated");
1410   }
1411 #endif
1412 
1413   return true;
1414 }
1415 
1416 // For concurrent GCs, there must be a handshake between unlink and flush
1417 void nmethod::unlink() {
1418   if (_unlinked_next != nullptr) {
1419     // Already unlinked. It can be invoked twice because concurrent code cache
1420     // unloading might need to restart when inline cache cleaning fails due to
1421     // running out of ICStubs, which can only be refilled at safepoints
1422     return;
1423   }
1424 
1425   flush_dependencies();
1426 
1427   // unlink_from_method will take the CompiledMethod_lock.
1428   // In this case we don't strictly need it when unlinking nmethods from
1429   // the Method, because it is only concurrently unlinked by
1430   // the entry barrier, which acquires the per nmethod lock.
1431   unlink_from_method();
1432   clear_ic_callsites();
1433 
1434   if (is_osr_method()) {
1435     invalidate_osr_method();
1436   }
1437 
1438 #if INCLUDE_JVMCI
1439   // Clear the link between this nmethod and a HotSpotNmethod mirror
1440   JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
1441   if (nmethod_data != nullptr) {
1442     nmethod_data->invalidate_nmethod_mirror(this);
1443   }
1444 #endif
1445 
1446   // Post before flushing as jmethodID is being used
1447   post_compiled_method_unload();
1448 
1449   // Register for flushing when it is safe. For concurrent class unloading,
1450   // that would be after the unloading handshake, and for STW class unloading
1451   // that would be when getting back to the VM thread.
1452   CodeCache::register_unlinked(this);
1453 }
1454 
1455 void nmethod::flush() {
1456   MutexLocker ml(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1457 
1458   // completely deallocate this method
1459   Events::log(Thread::current(), "flushing nmethod " INTPTR_FORMAT, p2i(this));
1460   log_debug(codecache)("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
1461                        "/Free CodeCache:" SIZE_FORMAT "Kb",
1462                        is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
1463                        CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
1464 
1465   // We need to deallocate any ExceptionCache data.
1466   // Note that we do not need to grab the nmethod lock for this, it
1467   // better be thread safe if we're disposing of it!
1468   ExceptionCache* ec = exception_cache();
1469   while(ec != nullptr) {
1470     ExceptionCache* next = ec->next();
1471     delete ec;
1472     ec = next;
1473   }
1474 
1475   Universe::heap()->unregister_nmethod(this);
1476   CodeCache::unregister_old_nmethod(this);
1477 
1478   CodeBlob::flush();
1479   CodeCache::free(this);
1480 }
1481 
1482 oop nmethod::oop_at(int index) const {
1483   if (index == 0) {
1484     return nullptr;
1485   }
1486   return NMethodAccess<AS_NO_KEEPALIVE>::oop_load(oop_addr_at(index));
1487 }
1488 
1489 oop nmethod::oop_at_phantom(int index) const {
1490   if (index == 0) {
1491     return nullptr;
1492   }
1493   return NMethodAccess<ON_PHANTOM_OOP_REF>::oop_load(oop_addr_at(index));
1494 }
1495 
1496 //
1497 // Notify all classes this nmethod is dependent on that it is no
1498 // longer dependent.
1499 
1500 void nmethod::flush_dependencies() {
1501   if (!has_flushed_dependencies()) {
1502     set_has_flushed_dependencies();
1503     for (Dependencies::DepStream deps(this); deps.next(); ) {
1504       if (deps.type() == Dependencies::call_site_target_value) {
1505         // CallSite dependencies are managed on per-CallSite instance basis.
1506         oop call_site = deps.argument_oop(0);
1507         MethodHandles::clean_dependency_context(call_site);
1508       } else {
1509         InstanceKlass* ik = deps.context_type();
1510         if (ik == nullptr) {
1511           continue;  // ignore things like evol_method
1512         }
1513         // During GC liveness of dependee determines class that needs to be updated.
1514         // The GC may clean dependency contexts concurrently and in parallel.
1515         ik->clean_dependency_context();
1516       }
1517     }
1518   }
1519 }
1520 
1521 void nmethod::post_compiled_method(CompileTask* task) {
1522   task->mark_success();
1523   task->set_nm_content_size(content_size());
1524   task->set_nm_insts_size(insts_size());
1525   task->set_nm_total_size(total_size());
1526 
1527   // JVMTI -- compiled method notification (must be done outside lock)
1528   post_compiled_method_load_event();
1529 
1530   if (CompilationLog::log() != nullptr) {
1531     CompilationLog::log()->log_nmethod(JavaThread::current(), this);
1532   }
1533 
1534   const DirectiveSet* directive = task->directive();
1535   maybe_print_nmethod(directive);
1536 }
1537 
1538 // ------------------------------------------------------------------
1539 // post_compiled_method_load_event
1540 // new method for install_code() path
1541 // Transfer information from compilation to jvmti
1542 void nmethod::post_compiled_method_load_event(JvmtiThreadState* state) {
1543   // This is a bad time for a safepoint.  We don't want
1544   // this nmethod to get unloaded while we're queueing the event.
1545   NoSafepointVerifier nsv;
1546 
1547   Method* m = method();
1548   HOTSPOT_COMPILED_METHOD_LOAD(
1549       (char *) m->klass_name()->bytes(),
1550       m->klass_name()->utf8_length(),
1551       (char *) m->name()->bytes(),
1552       m->name()->utf8_length(),
1553       (char *) m->signature()->bytes(),
1554       m->signature()->utf8_length(),
1555       insts_begin(), insts_size());
1556 
1557 
1558   if (JvmtiExport::should_post_compiled_method_load()) {
1559     // Only post unload events if load events are found.
1560     set_load_reported();
1561     // If a JavaThread hasn't been passed in, let the Service thread
1562     // (which is a real Java thread) post the event
1563     JvmtiDeferredEvent event = JvmtiDeferredEvent::compiled_method_load_event(this);
1564     if (state == nullptr) {
1565       // Execute any barrier code for this nmethod as if it's called, since
1566       // keeping it alive looks like stack walking.
1567       run_nmethod_entry_barrier();
1568       ServiceThread::enqueue_deferred_event(&event);
1569     } else {
1570       // This enters the nmethod barrier outside in the caller.
1571       state->enqueue_event(&event);
1572     }
1573   }
1574 }
1575 
1576 void nmethod::post_compiled_method_unload() {
1577   assert(_method != nullptr, "just checking");
1578   DTRACE_METHOD_UNLOAD_PROBE(method());
1579 
1580   // If a JVMTI agent has enabled the CompiledMethodUnload event then
1581   // post the event. The Method* will not be valid when this is freed.
1582 
1583   // Don't bother posting the unload if the load event wasn't posted.
1584   if (load_reported() && JvmtiExport::should_post_compiled_method_unload()) {
1585     JvmtiDeferredEvent event =
1586       JvmtiDeferredEvent::compiled_method_unload_event(
1587           method()->jmethod_id(), insts_begin());
1588     ServiceThread::enqueue_deferred_event(&event);
1589   }
1590 }
1591 
1592 // Iterate over metadata calling this function.   Used by RedefineClasses
1593 void nmethod::metadata_do(MetadataClosure* f) {
1594   {
1595     // Visit all immediate references that are embedded in the instruction stream.
1596     RelocIterator iter(this, oops_reloc_begin());
1597     while (iter.next()) {
1598       if (iter.type() == relocInfo::metadata_type) {
1599         metadata_Relocation* r = iter.metadata_reloc();
1600         // In this metadata, we must only follow those metadatas directly embedded in
1601         // the code.  Other metadatas (oop_index>0) are seen as part of
1602         // the metadata section below.
1603         assert(1 == (r->metadata_is_immediate()) +
1604                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1605                "metadata must be found in exactly one place");
1606         if (r->metadata_is_immediate() && r->metadata_value() != nullptr) {
1607           Metadata* md = r->metadata_value();
1608           if (md != _method) f->do_metadata(md);
1609         }
1610       } else if (iter.type() == relocInfo::virtual_call_type) {
1611         // Check compiledIC holders associated with this nmethod
1612         ResourceMark rm;
1613         CompiledIC *ic = CompiledIC_at(&iter);
1614         if (ic->is_icholder_call()) {
1615           CompiledICHolder* cichk = ic->cached_icholder();
1616           f->do_metadata(cichk->holder_metadata());
1617           f->do_metadata(cichk->holder_klass());
1618         } else {
1619           Metadata* ic_oop = ic->cached_metadata();
1620           if (ic_oop != nullptr) {
1621             f->do_metadata(ic_oop);
1622           }
1623         }
1624       }
1625     }
1626   }
1627 
1628   // Visit the metadata section
1629   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1630     if (*p == Universe::non_oop_word() || *p == nullptr)  continue;  // skip non-oops
1631     Metadata* md = *p;
1632     f->do_metadata(md);
1633   }
1634 
1635   // Visit metadata not embedded in the other places.
1636   if (_method != nullptr) f->do_metadata(_method);
1637 }
1638 
1639 // Heuristic for nuking nmethods even though their oops are live.
1640 // Main purpose is to reduce code cache pressure and get rid of
1641 // nmethods that don't seem to be all that relevant any longer.
1642 bool nmethod::is_cold() {
1643   if (!MethodFlushing || is_native_method() || is_not_installed()) {
1644     // No heuristic unloading at all
1645     return false;
1646   }
1647 
1648   if (!is_maybe_on_stack() && is_not_entrant()) {
1649     // Not entrant nmethods that are not on any stack can just
1650     // be removed
1651     return true;
1652   }
1653 
1654   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
1655   if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
1656     // On platforms that don't support nmethod entry barriers, we can't
1657     // trust the temporal aspect of the gc epochs. So we can't detect
1658     // cold nmethods on such platforms.
1659     return false;
1660   }
1661 
1662   if (!UseCodeCacheFlushing) {
1663     // Bail out if we don't heuristically remove nmethods
1664     return false;
1665   }
1666 
1667   // Other code can be phased out more gradually after N GCs
1668   return CodeCache::previous_completed_gc_marking_cycle() > _gc_epoch + 2 * CodeCache::cold_gc_count();
1669 }
1670 
1671 // The _is_unloading_state encodes a tuple comprising the unloading cycle
1672 // and the result of IsUnloadingBehaviour::is_unloading() for that cycle.
1673 // This is the bit layout of the _is_unloading_state byte: 00000CCU
1674 // CC refers to the cycle, which has 2 bits, and U refers to the result of
1675 // IsUnloadingBehaviour::is_unloading() for that unloading cycle.
1676 
1677 class IsUnloadingState: public AllStatic {
1678   static const uint8_t _is_unloading_mask = 1;
1679   static const uint8_t _is_unloading_shift = 0;
1680   static const uint8_t _unloading_cycle_mask = 6;
1681   static const uint8_t _unloading_cycle_shift = 1;
1682 
1683   static uint8_t set_is_unloading(uint8_t state, bool value) {
1684     state &= (uint8_t)~_is_unloading_mask;
1685     if (value) {
1686       state |= 1 << _is_unloading_shift;
1687     }
1688     assert(is_unloading(state) == value, "unexpected unloading cycle overflow");
1689     return state;
1690   }
1691 
1692   static uint8_t set_unloading_cycle(uint8_t state, uint8_t value) {
1693     state &= (uint8_t)~_unloading_cycle_mask;
1694     state |= (uint8_t)(value << _unloading_cycle_shift);
1695     assert(unloading_cycle(state) == value, "unexpected unloading cycle overflow");
1696     return state;
1697   }
1698 
1699 public:
1700   static bool is_unloading(uint8_t state) { return (state & _is_unloading_mask) >> _is_unloading_shift == 1; }
1701   static uint8_t unloading_cycle(uint8_t state) { return (state & _unloading_cycle_mask) >> _unloading_cycle_shift; }
1702 
1703   static uint8_t create(bool is_unloading, uint8_t unloading_cycle) {
1704     uint8_t state = 0;
1705     state = set_is_unloading(state, is_unloading);
1706     state = set_unloading_cycle(state, unloading_cycle);
1707     return state;
1708   }
1709 };
1710 
1711 bool nmethod::is_unloading() {
1712   uint8_t state = Atomic::load(&_is_unloading_state);
1713   bool state_is_unloading = IsUnloadingState::is_unloading(state);
1714   if (state_is_unloading) {
1715     return true;
1716   }
1717   uint8_t state_unloading_cycle = IsUnloadingState::unloading_cycle(state);
1718   uint8_t current_cycle = CodeCache::unloading_cycle();
1719   if (state_unloading_cycle == current_cycle) {
1720     return false;
1721   }
1722 
1723   // The IsUnloadingBehaviour is responsible for calculating if the nmethod
1724   // should be unloaded. This can be either because there is a dead oop,
1725   // or because is_cold() heuristically determines it is time to unload.
1726   state_unloading_cycle = current_cycle;
1727   state_is_unloading = IsUnloadingBehaviour::is_unloading(this);
1728   uint8_t new_state = IsUnloadingState::create(state_is_unloading, state_unloading_cycle);
1729 
1730   // Note that if an nmethod has dead oops, everyone will agree that the
1731   // nmethod is_unloading. However, the is_cold heuristics can yield
1732   // different outcomes, so we guard the computed result with a CAS
1733   // to ensure all threads have a shared view of whether an nmethod
1734   // is_unloading or not.
1735   uint8_t found_state = Atomic::cmpxchg(&_is_unloading_state, state, new_state, memory_order_relaxed);
1736 
1737   if (found_state == state) {
1738     // First to change state, we win
1739     return state_is_unloading;
1740   } else {
1741     // State already set, so use it
1742     return IsUnloadingState::is_unloading(found_state);
1743   }
1744 }
1745 
1746 void nmethod::clear_unloading_state() {
1747   uint8_t state = IsUnloadingState::create(false, CodeCache::unloading_cycle());
1748   Atomic::store(&_is_unloading_state, state);
1749 }
1750 
1751 
1752 // This is called at the end of the strong tracing/marking phase of a
1753 // GC to unload an nmethod if it contains otherwise unreachable
1754 // oops or is heuristically found to be not important.
1755 void nmethod::do_unloading(bool unloading_occurred) {
1756   // Make sure the oop's ready to receive visitors
1757   if (is_unloading()) {
1758     unlink();
1759   } else {
1760     guarantee(unload_nmethod_caches(unloading_occurred),
1761               "Should not need transition stubs");
1762     BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
1763     if (bs_nm != nullptr) {
1764       bs_nm->disarm(this);
1765     }
1766   }
1767 }
1768 
1769 void nmethod::oops_do(OopClosure* f, bool allow_dead) {
1770   // Prevent extra code cache walk for platforms that don't have immediate oops.
1771   if (relocInfo::mustIterateImmediateOopsInCode()) {
1772     RelocIterator iter(this, oops_reloc_begin());
1773 
1774     while (iter.next()) {
1775       if (iter.type() == relocInfo::oop_type ) {
1776         oop_Relocation* r = iter.oop_reloc();
1777         // In this loop, we must only follow those oops directly embedded in
1778         // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
1779         assert(1 == (r->oop_is_immediate()) +
1780                (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1781                "oop must be found in exactly one place");
1782         if (r->oop_is_immediate() && r->oop_value() != nullptr) {
1783           f->do_oop(r->oop_addr());
1784         }
1785       }
1786     }
1787   }
1788 
1789   // Scopes
1790   // This includes oop constants not inlined in the code stream.
1791   for (oop* p = oops_begin(); p < oops_end(); p++) {
1792     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1793     f->do_oop(p);
1794   }
1795 }
1796 
1797 void nmethod::follow_nmethod(OopIterateClosure* cl) {
1798   // Process oops in the nmethod
1799   oops_do(cl);
1800 
1801   // CodeCache unloading support
1802   mark_as_maybe_on_stack();
1803 
1804   BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
1805   bs_nm->disarm(this);
1806 
1807   // There's an assumption made that this function is not used by GCs that
1808   // relocate objects, and therefore we don't call fix_oop_relocations.
1809 }
1810 
1811 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1812 
1813 void nmethod::oops_do_log_change(const char* state) {
1814   LogTarget(Trace, gc, nmethod) lt;
1815   if (lt.is_enabled()) {
1816     LogStream ls(lt);
1817     CompileTask::print(&ls, this, state, true /* short_form */);
1818   }
1819 }
1820 
1821 bool nmethod::oops_do_try_claim() {
1822   if (oops_do_try_claim_weak_request()) {
1823     nmethod* result = oops_do_try_add_to_list_as_weak_done();
1824     assert(result == nullptr, "adding to global list as weak done must always succeed.");
1825     return true;
1826   }
1827   return false;
1828 }
1829 
1830 bool nmethod::oops_do_try_claim_weak_request() {
1831   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
1832 
1833   if ((_oops_do_mark_link == nullptr) &&
1834       (Atomic::replace_if_null(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag)))) {
1835     oops_do_log_change("oops_do, mark weak request");
1836     return true;
1837   }
1838   return false;
1839 }
1840 
1841 void nmethod::oops_do_set_strong_done(nmethod* old_head) {
1842   _oops_do_mark_link = mark_link(old_head, claim_strong_done_tag);
1843 }
1844 
1845 nmethod::oops_do_mark_link* nmethod::oops_do_try_claim_strong_done() {
1846   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
1847 
1848   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));
1849   if (old_next == nullptr) {
1850     oops_do_log_change("oops_do, mark strong done");
1851   }
1852   return old_next;
1853 }
1854 
1855 nmethod::oops_do_mark_link* nmethod::oops_do_try_add_strong_request(nmethod::oops_do_mark_link* next) {
1856   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
1857   assert(next == mark_link(this, claim_weak_request_tag), "Should be claimed as weak");
1858 
1859   oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(this, claim_strong_request_tag));
1860   if (old_next == next) {
1861     oops_do_log_change("oops_do, mark strong request");
1862   }
1863   return old_next;
1864 }
1865 
1866 bool nmethod::oops_do_try_claim_weak_done_as_strong_done(nmethod::oops_do_mark_link* next) {
1867   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
1868   assert(extract_state(next) == claim_weak_done_tag, "Should be claimed as weak done");
1869 
1870   oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(extract_nmethod(next), claim_strong_done_tag));
1871   if (old_next == next) {
1872     oops_do_log_change("oops_do, mark weak done -> mark strong done");
1873     return true;
1874   }
1875   return false;
1876 }
1877 
1878 nmethod* nmethod::oops_do_try_add_to_list_as_weak_done() {
1879   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
1880 
1881   assert(extract_state(_oops_do_mark_link) == claim_weak_request_tag ||
1882          extract_state(_oops_do_mark_link) == claim_strong_request_tag,
1883          "must be but is nmethod " PTR_FORMAT " %u", p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
1884 
1885   nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this);
1886   // Self-loop if needed.
1887   if (old_head == nullptr) {
1888     old_head = this;
1889   }
1890   // Try to install end of list and weak done tag.
1891   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)) {
1892     oops_do_log_change("oops_do, mark weak done");
1893     return nullptr;
1894   } else {
1895     return old_head;
1896   }
1897 }
1898 
1899 void nmethod::oops_do_add_to_list_as_strong_done() {
1900   assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
1901 
1902   nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this);
1903   // Self-loop if needed.
1904   if (old_head == nullptr) {
1905     old_head = this;
1906   }
1907   assert(_oops_do_mark_link == mark_link(this, claim_strong_done_tag), "must be but is nmethod " PTR_FORMAT " state %u",
1908          p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
1909 
1910   oops_do_set_strong_done(old_head);
1911 }
1912 
1913 void nmethod::oops_do_process_weak(OopsDoProcessor* p) {
1914   if (!oops_do_try_claim_weak_request()) {
1915     // Failed to claim for weak processing.
1916     oops_do_log_change("oops_do, mark weak request fail");
1917     return;
1918   }
1919 
1920   p->do_regular_processing(this);
1921 
1922   nmethod* old_head = oops_do_try_add_to_list_as_weak_done();
1923   if (old_head == nullptr) {
1924     return;
1925   }
1926   oops_do_log_change("oops_do, mark weak done fail");
1927   // Adding to global list failed, another thread added a strong request.
1928   assert(extract_state(_oops_do_mark_link) == claim_strong_request_tag,
1929          "must be but is %u", extract_state(_oops_do_mark_link));
1930 
1931   oops_do_log_change("oops_do, mark weak request -> mark strong done");
1932 
1933   oops_do_set_strong_done(old_head);
1934   // Do missing strong processing.
1935   p->do_remaining_strong_processing(this);
1936 }
1937 
1938 void nmethod::oops_do_process_strong(OopsDoProcessor* p) {
1939   oops_do_mark_link* next_raw = oops_do_try_claim_strong_done();
1940   if (next_raw == nullptr) {
1941     p->do_regular_processing(this);
1942     oops_do_add_to_list_as_strong_done();
1943     return;
1944   }
1945   // Claim failed. Figure out why and handle it.
1946   if (oops_do_has_weak_request(next_raw)) {
1947     oops_do_mark_link* old = next_raw;
1948     // Claim failed because being weak processed (state == "weak request").
1949     // Try to request deferred strong processing.
1950     next_raw = oops_do_try_add_strong_request(old);
1951     if (next_raw == old) {
1952       // Successfully requested deferred strong processing.
1953       return;
1954     }
1955     // Failed because of a concurrent transition. No longer in "weak request" state.
1956   }
1957   if (oops_do_has_any_strong_state(next_raw)) {
1958     // Already claimed for strong processing or requested for such.
1959     return;
1960   }
1961   if (oops_do_try_claim_weak_done_as_strong_done(next_raw)) {
1962     // Successfully claimed "weak done" as "strong done". Do the missing marking.
1963     p->do_remaining_strong_processing(this);
1964     return;
1965   }
1966   // Claim failed, some other thread got it.
1967 }
1968 
1969 void nmethod::oops_do_marking_prologue() {
1970   assert_at_safepoint();
1971 
1972   log_trace(gc, nmethod)("oops_do_marking_prologue");
1973   assert(_oops_do_mark_nmethods == nullptr, "must be empty");
1974 }
1975 
1976 void nmethod::oops_do_marking_epilogue() {
1977   assert_at_safepoint();
1978 
1979   nmethod* next = _oops_do_mark_nmethods;
1980   _oops_do_mark_nmethods = nullptr;
1981   if (next != nullptr) {
1982     nmethod* cur;
1983     do {
1984       cur = next;
1985       next = extract_nmethod(cur->_oops_do_mark_link);
1986       cur->_oops_do_mark_link = nullptr;
1987       DEBUG_ONLY(cur->verify_oop_relocations());
1988 
1989       LogTarget(Trace, gc, nmethod) lt;
1990       if (lt.is_enabled()) {
1991         LogStream ls(lt);
1992         CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
1993       }
1994       // End if self-loop has been detected.
1995     } while (cur != next);
1996   }
1997   log_trace(gc, nmethod)("oops_do_marking_epilogue");
1998 }
1999 
2000 inline bool includes(void* p, void* from, void* to) {
2001   return from <= p && p < to;
2002 }
2003 
2004 
2005 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2006   assert(count >= 2, "must be sentinel values, at least");
2007 
2008 #ifdef ASSERT
2009   // must be sorted and unique; we do a binary search in find_pc_desc()
2010   int prev_offset = pcs[0].pc_offset();
2011   assert(prev_offset == PcDesc::lower_offset_limit,
2012          "must start with a sentinel");
2013   for (int i = 1; i < count; i++) {
2014     int this_offset = pcs[i].pc_offset();
2015     assert(this_offset > prev_offset, "offsets must be sorted");
2016     prev_offset = this_offset;
2017   }
2018   assert(prev_offset == PcDesc::upper_offset_limit,
2019          "must end with a sentinel");
2020 #endif //ASSERT
2021 
2022   // Search for MethodHandle invokes and tag the nmethod.
2023   for (int i = 0; i < count; i++) {
2024     if (pcs[i].is_method_handle_invoke()) {
2025       set_has_method_handle_invokes(true);
2026       break;
2027     }
2028   }
2029   assert(has_method_handle_invokes() == (_deopt_mh_handler_begin != nullptr), "must have deopt mh handler");
2030 
2031   int size = count * sizeof(PcDesc);
2032   assert(scopes_pcs_size() >= size, "oob");
2033   memcpy(scopes_pcs_begin(), pcs, size);
2034 
2035   // Adjust the final sentinel downward.
2036   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2037   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2038   last_pc->set_pc_offset(content_size() + 1);
2039   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2040     // Fill any rounding gaps with copies of the last record.
2041     last_pc[1] = last_pc[0];
2042   }
2043   // The following assert could fail if sizeof(PcDesc) is not
2044   // an integral multiple of oopSize (the rounding term).
2045   // If it fails, change the logic to always allocate a multiple
2046   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2047   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2048 }
2049 
2050 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2051   assert(scopes_data_size() >= size, "oob");
2052   memcpy(scopes_data_begin(), buffer, size);
2053 }
2054 
2055 #ifdef ASSERT
2056 static PcDesc* linear_search(const PcDescSearch& search, int pc_offset, bool approximate) {
2057   PcDesc* lower = search.scopes_pcs_begin();
2058   PcDesc* upper = search.scopes_pcs_end();
2059   lower += 1; // exclude initial sentinel
2060   PcDesc* res = nullptr;
2061   for (PcDesc* p = lower; p < upper; p++) {
2062     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
2063     if (match_desc(p, pc_offset, approximate)) {
2064       if (res == nullptr)
2065         res = p;
2066       else
2067         res = (PcDesc*) badAddress;
2068     }
2069   }
2070   return res;
2071 }
2072 #endif
2073 
2074 
2075 // Finds a PcDesc with real-pc equal to "pc"
2076 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, const PcDescSearch& search) {
2077   address base_address = search.code_begin();
2078   if ((pc < base_address) ||
2079       (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2080     return nullptr;  // PC is wildly out of range
2081   }
2082   int pc_offset = (int) (pc - base_address);
2083 
2084   // Check the PcDesc cache if it contains the desired PcDesc
2085   // (This as an almost 100% hit rate.)
2086   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2087   if (res != nullptr) {
2088     assert(res == linear_search(search, pc_offset, approximate), "cache ok");
2089     return res;
2090   }
2091 
2092   // Fallback algorithm: quasi-linear search for the PcDesc
2093   // Find the last pc_offset less than the given offset.
2094   // The successor must be the required match, if there is a match at all.
2095   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2096   PcDesc* lower = search.scopes_pcs_begin();
2097   PcDesc* upper = search.scopes_pcs_end();
2098   upper -= 1; // exclude final sentinel
2099   if (lower >= upper)  return nullptr;  // native method; no PcDescs at all
2100 
2101 #define assert_LU_OK \
2102   /* invariant on lower..upper during the following search: */ \
2103   assert(lower->pc_offset() <  pc_offset, "sanity"); \
2104   assert(upper->pc_offset() >= pc_offset, "sanity")
2105   assert_LU_OK;
2106 
2107   // Use the last successful return as a split point.
2108   PcDesc* mid = _pc_desc_cache.last_pc_desc();
2109   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2110   if (mid->pc_offset() < pc_offset) {
2111     lower = mid;
2112   } else {
2113     upper = mid;
2114   }
2115 
2116   // Take giant steps at first (4096, then 256, then 16, then 1)
2117   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2118   const int RADIX = (1 << LOG2_RADIX);
2119   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2120     while ((mid = lower + step) < upper) {
2121       assert_LU_OK;
2122       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2123       if (mid->pc_offset() < pc_offset) {
2124         lower = mid;
2125       } else {
2126         upper = mid;
2127         break;
2128       }
2129     }
2130     assert_LU_OK;
2131   }
2132 
2133   // Sneak up on the value with a linear search of length ~16.
2134   while (true) {
2135     assert_LU_OK;
2136     mid = lower + 1;
2137     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2138     if (mid->pc_offset() < pc_offset) {
2139       lower = mid;
2140     } else {
2141       upper = mid;
2142       break;
2143     }
2144   }
2145 #undef assert_LU_OK
2146 
2147   if (match_desc(upper, pc_offset, approximate)) {
2148     assert(upper == linear_search(search, pc_offset, approximate), "search ok");
2149     if (!Thread::current_in_asgct()) {
2150       // we don't want to modify the cache if we're in ASGCT
2151       // which is typically called in a signal handler
2152       _pc_desc_cache.add_pc_desc(upper);
2153     }
2154     return upper;
2155   } else {
2156     assert(nullptr == linear_search(search, pc_offset, approximate), "search ok");
2157     return nullptr;
2158   }
2159 }
2160 
2161 bool nmethod::check_dependency_on(DepChange& changes) {
2162   // What has happened:
2163   // 1) a new class dependee has been added
2164   // 2) dependee and all its super classes have been marked
2165   bool found_check = false;  // set true if we are upset
2166   for (Dependencies::DepStream deps(this); deps.next(); ) {
2167     // Evaluate only relevant dependencies.
2168     if (deps.spot_check_dependency_at(changes) != nullptr) {
2169       found_check = true;
2170       NOT_DEBUG(break);
2171     }
2172   }
2173   return found_check;
2174 }
2175 
2176 // Called from mark_for_deoptimization, when dependee is invalidated.
2177 bool nmethod::is_dependent_on_method(Method* dependee) {
2178   for (Dependencies::DepStream deps(this); deps.next(); ) {
2179     if (deps.type() != Dependencies::evol_method)
2180       continue;
2181     Method* method = deps.method_argument(0);
2182     if (method == dependee) return true;
2183   }
2184   return false;
2185 }
2186 
2187 void nmethod_init() {
2188   // make sure you didn't forget to adjust the filler fields
2189   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2190 }
2191 
2192 // -----------------------------------------------------------------------------
2193 // Verification
2194 
2195 class VerifyOopsClosure: public OopClosure {
2196   nmethod* _nm;
2197   bool     _ok;
2198 public:
2199   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2200   bool ok() { return _ok; }
2201   virtual void do_oop(oop* p) {
2202     if (oopDesc::is_oop_or_null(*p)) return;
2203     // Print diagnostic information before calling print_nmethod().
2204     // Assertions therein might prevent call from returning.
2205     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2206                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2207     if (_ok) {
2208       _nm->print_nmethod(true);
2209       _ok = false;
2210     }
2211   }
2212   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2213 };
2214 
2215 class VerifyMetadataClosure: public MetadataClosure {
2216  public:
2217   void do_metadata(Metadata* md) {
2218     if (md->is_method()) {
2219       Method* method = (Method*)md;
2220       assert(!method->is_old(), "Should not be installing old methods");
2221     }
2222   }
2223 };
2224 
2225 
2226 void nmethod::verify() {
2227   if (is_not_entrant())
2228     return;
2229 
2230   // Make sure all the entry points are correctly aligned for patching.
2231   NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2232 
2233   // assert(oopDesc::is_oop(method()), "must be valid");
2234 
2235   ResourceMark rm;
2236 
2237   if (!CodeCache::contains(this)) {
2238     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2239   }
2240 
2241   if(is_native_method() )
2242     return;
2243 
2244   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2245   if (nm != this) {
2246     fatal("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2247   }
2248 
2249   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2250     if (! p->verify(this)) {
2251       tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2252     }
2253   }
2254 
2255 #ifdef ASSERT
2256 #if INCLUDE_JVMCI
2257   {
2258     // Verify that implicit exceptions that deoptimize have a PcDesc and OopMap
2259     ImmutableOopMapSet* oms = oop_maps();
2260     ImplicitExceptionTable implicit_table(this);
2261     for (uint i = 0; i < implicit_table.len(); i++) {
2262       int exec_offset = (int) implicit_table.get_exec_offset(i);
2263       if (implicit_table.get_exec_offset(i) == implicit_table.get_cont_offset(i)) {
2264         assert(pc_desc_at(code_begin() + exec_offset) != nullptr, "missing PcDesc");
2265         bool found = false;
2266         for (int i = 0, imax = oms->count(); i < imax; i++) {
2267           if (oms->pair_at(i)->pc_offset() == exec_offset) {
2268             found = true;
2269             break;
2270           }
2271         }
2272         assert(found, "missing oopmap");
2273       }
2274     }
2275   }
2276 #endif
2277 #endif
2278 
2279   VerifyOopsClosure voc(this);
2280   oops_do(&voc);
2281   assert(voc.ok(), "embedded oops must be OK");
2282   Universe::heap()->verify_nmethod(this);
2283 
2284   assert(_oops_do_mark_link == nullptr, "_oops_do_mark_link for %s should be nullptr but is " PTR_FORMAT,
2285          nm->method()->external_name(), p2i(_oops_do_mark_link));
2286   verify_scopes();
2287 
2288   CompiledICLocker nm_verify(this);
2289   VerifyMetadataClosure vmc;
2290   metadata_do(&vmc);
2291 }
2292 
2293 
2294 void nmethod::verify_interrupt_point(address call_site) {
2295 
2296   // Verify IC only when nmethod installation is finished.
2297   if (!is_not_installed()) {
2298     if (CompiledICLocker::is_safe(this)) {
2299       CompiledIC_at(this, call_site);
2300     } else {
2301       CompiledICLocker ml_verify(this);
2302       CompiledIC_at(this, call_site);
2303     }
2304   }
2305 
2306   HandleMark hm(Thread::current());
2307 
2308   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2309   assert(pd != nullptr, "PcDesc must exist");
2310   for (ScopeDesc* sd = new ScopeDesc(this, pd);
2311        !sd->is_top(); sd = sd->sender()) {
2312     sd->verify();
2313   }
2314 }
2315 
2316 void nmethod::verify_scopes() {
2317   if( !method() ) return;       // Runtime stubs have no scope
2318   if (method()->is_native()) return; // Ignore stub methods.
2319   // iterate through all interrupt point
2320   // and verify the debug information is valid.
2321   RelocIterator iter((nmethod*)this);
2322   while (iter.next()) {
2323     address stub = nullptr;
2324     switch (iter.type()) {
2325       case relocInfo::virtual_call_type:
2326         verify_interrupt_point(iter.addr());
2327         break;
2328       case relocInfo::opt_virtual_call_type:
2329         stub = iter.opt_virtual_call_reloc()->static_stub();
2330         verify_interrupt_point(iter.addr());
2331         break;
2332       case relocInfo::static_call_type:
2333         stub = iter.static_call_reloc()->static_stub();
2334         //verify_interrupt_point(iter.addr());
2335         break;
2336       case relocInfo::runtime_call_type:
2337       case relocInfo::runtime_call_w_cp_type: {
2338         address destination = iter.reloc()->value();
2339         // Right now there is no way to find out which entries support
2340         // an interrupt point.  It would be nice if we had this
2341         // information in a table.
2342         break;
2343       }
2344       default:
2345         break;
2346     }
2347     assert(stub == nullptr || stub_contains(stub), "static call stub outside stub section");
2348   }
2349 }
2350 
2351 
2352 // -----------------------------------------------------------------------------
2353 // Printing operations
2354 
2355 void nmethod::print() const {
2356   ttyLocker ttyl;   // keep the following output all in one block
2357   print(tty);
2358 }
2359 
2360 void nmethod::print(outputStream* st) const {
2361   ResourceMark rm;
2362 
2363   st->print("Compiled method ");
2364 
2365   if (is_compiled_by_c1()) {
2366     st->print("(c1) ");
2367   } else if (is_compiled_by_c2()) {
2368     st->print("(c2) ");
2369   } else if (is_compiled_by_jvmci()) {
2370     st->print("(JVMCI) ");
2371   } else {
2372     st->print("(n/a) ");
2373   }
2374 
2375   print_on(st, nullptr);
2376 
2377   if (WizardMode) {
2378     st->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
2379     st->print(" for method " INTPTR_FORMAT , p2i(method()));
2380     st->print(" { ");
2381     st->print_cr("%s ", state());
2382     st->print_cr("}:");
2383   }
2384   if (size              () > 0) st->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2385                                              p2i(this),
2386                                              p2i(this) + size(),
2387                                              size());
2388   if (relocation_size   () > 0) st->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2389                                              p2i(relocation_begin()),
2390                                              p2i(relocation_end()),
2391                                              relocation_size());
2392   if (consts_size       () > 0) st->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2393                                              p2i(consts_begin()),
2394                                              p2i(consts_end()),
2395                                              consts_size());
2396   if (insts_size        () > 0) st->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2397                                              p2i(insts_begin()),
2398                                              p2i(insts_end()),
2399                                              insts_size());
2400   if (stub_size         () > 0) st->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2401                                              p2i(stub_begin()),
2402                                              p2i(stub_end()),
2403                                              stub_size());
2404   if (oops_size         () > 0) st->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2405                                              p2i(oops_begin()),
2406                                              p2i(oops_end()),
2407                                              oops_size());
2408   if (metadata_size     () > 0) st->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2409                                              p2i(metadata_begin()),
2410                                              p2i(metadata_end()),
2411                                              metadata_size());
2412   if (scopes_data_size  () > 0) st->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2413                                              p2i(scopes_data_begin()),
2414                                              p2i(scopes_data_end()),
2415                                              scopes_data_size());
2416   if (scopes_pcs_size   () > 0) st->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2417                                              p2i(scopes_pcs_begin()),
2418                                              p2i(scopes_pcs_end()),
2419                                              scopes_pcs_size());
2420   if (dependencies_size () > 0) st->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2421                                              p2i(dependencies_begin()),
2422                                              p2i(dependencies_end()),
2423                                              dependencies_size());
2424   if (handler_table_size() > 0) st->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2425                                              p2i(handler_table_begin()),
2426                                              p2i(handler_table_end()),
2427                                              handler_table_size());
2428   if (nul_chk_table_size() > 0) st->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2429                                              p2i(nul_chk_table_begin()),
2430                                              p2i(nul_chk_table_end()),
2431                                              nul_chk_table_size());
2432 #if INCLUDE_JVMCI
2433   if (speculations_size () > 0) st->print_cr(" speculations   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2434                                              p2i(speculations_begin()),
2435                                              p2i(speculations_end()),
2436                                              speculations_size());
2437   if (jvmci_data_size   () > 0) st->print_cr(" JVMCI data     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2438                                              p2i(jvmci_data_begin()),
2439                                              p2i(jvmci_data_end()),
2440                                              jvmci_data_size());
2441 #endif
2442 }
2443 
2444 void nmethod::print_code() {
2445   ResourceMark m;
2446   ttyLocker ttyl;
2447   // Call the specialized decode method of this class.
2448   decode(tty);
2449 }
2450 
2451 #ifndef PRODUCT  // called InstanceKlass methods are available only then. Declared as PRODUCT_RETURN
2452 
2453 void nmethod::print_dependencies_on(outputStream* out) {
2454   ResourceMark rm;
2455   stringStream st;
2456   st.print_cr("Dependencies:");
2457   for (Dependencies::DepStream deps(this); deps.next(); ) {
2458     deps.print_dependency(&st);
2459     InstanceKlass* ctxk = deps.context_type();
2460     if (ctxk != nullptr) {
2461       if (ctxk->is_dependent_nmethod(this)) {
2462         st.print_cr("   [nmethod<=klass]%s", ctxk->external_name());
2463       }
2464     }
2465     deps.log_dependency();  // put it into the xml log also
2466   }
2467   out->print_raw(st.as_string());
2468 }
2469 #endif
2470 
2471 #if defined(SUPPORT_DATA_STRUCTS)
2472 
2473 // Print the oops from the underlying CodeBlob.
2474 void nmethod::print_oops(outputStream* st) {
2475   ResourceMark m;
2476   st->print("Oops:");
2477   if (oops_begin() < oops_end()) {
2478     st->cr();
2479     for (oop* p = oops_begin(); p < oops_end(); p++) {
2480       Disassembler::print_location((unsigned char*)p, (unsigned char*)oops_begin(), (unsigned char*)oops_end(), st, true, false);
2481       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
2482       if (Universe::contains_non_oop_word(p)) {
2483         st->print_cr("NON_OOP");
2484         continue;  // skip non-oops
2485       }
2486       if (*p == nullptr) {
2487         st->print_cr("nullptr-oop");
2488         continue;  // skip non-oops
2489       }
2490       (*p)->print_value_on(st);
2491       st->cr();
2492     }
2493   } else {
2494     st->print_cr(" <list empty>");
2495   }
2496 }
2497 
2498 // Print metadata pool.
2499 void nmethod::print_metadata(outputStream* st) {
2500   ResourceMark m;
2501   st->print("Metadata:");
2502   if (metadata_begin() < metadata_end()) {
2503     st->cr();
2504     for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2505       Disassembler::print_location((unsigned char*)p, (unsigned char*)metadata_begin(), (unsigned char*)metadata_end(), st, true, false);
2506       st->print(PTR_FORMAT " ", *((uintptr_t*)p));
2507       if (*p && *p != Universe::non_oop_word()) {
2508         (*p)->print_value_on(st);
2509       }
2510       st->cr();
2511     }
2512   } else {
2513     st->print_cr(" <list empty>");
2514   }
2515 }
2516 
2517 #ifndef PRODUCT  // ScopeDesc::print_on() is available only then. Declared as PRODUCT_RETURN
2518 void nmethod::print_scopes_on(outputStream* st) {
2519   // Find the first pc desc for all scopes in the code and print it.
2520   ResourceMark rm;
2521   st->print("scopes:");
2522   if (scopes_pcs_begin() < scopes_pcs_end()) {
2523     st->cr();
2524     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2525       if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2526         continue;
2527 
2528       ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2529       while (sd != nullptr) {
2530         sd->print_on(st, p);  // print output ends with a newline
2531         sd = sd->sender();
2532       }
2533     }
2534   } else {
2535     st->print_cr(" <list empty>");
2536   }
2537 }
2538 #endif
2539 
2540 #ifndef PRODUCT  // RelocIterator does support printing only then.
2541 void nmethod::print_relocations() {
2542   ResourceMark m;       // in case methods get printed via the debugger
2543   tty->print_cr("relocations:");
2544   RelocIterator iter(this);
2545   iter.print();
2546 }
2547 #endif
2548 
2549 void nmethod::print_pcs_on(outputStream* st) {
2550   ResourceMark m;       // in case methods get printed via debugger
2551   st->print("pc-bytecode offsets:");
2552   if (scopes_pcs_begin() < scopes_pcs_end()) {
2553     st->cr();
2554     for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2555       p->print_on(st, this);  // print output ends with a newline
2556     }
2557   } else {
2558     st->print_cr(" <list empty>");
2559   }
2560 }
2561 
2562 void nmethod::print_handler_table() {
2563   ExceptionHandlerTable(this).print(code_begin());
2564 }
2565 
2566 void nmethod::print_nul_chk_table() {
2567   ImplicitExceptionTable(this).print(code_begin());
2568 }
2569 
2570 void nmethod::print_recorded_oop(int log_n, int i) {
2571   void* value;
2572 
2573   if (i == 0) {
2574     value = nullptr;
2575   } else {
2576     // Be careful around non-oop words. Don't create an oop
2577     // with that value, or it will assert in verification code.
2578     if (Universe::contains_non_oop_word(oop_addr_at(i))) {
2579       value = Universe::non_oop_word();
2580     } else {
2581       value = oop_at(i);
2582     }
2583   }
2584 
2585   tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(value));
2586 
2587   if (value == Universe::non_oop_word()) {
2588     tty->print("non-oop word");
2589   } else {
2590     if (value == 0) {
2591       tty->print("nullptr-oop");
2592     } else {
2593       oop_at(i)->print_value_on(tty);
2594     }
2595   }
2596 
2597   tty->cr();
2598 }
2599 
2600 void nmethod::print_recorded_oops() {
2601   const int n = oops_count();
2602   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
2603   tty->print("Recorded oops:");
2604   if (n > 0) {
2605     tty->cr();
2606     for (int i = 0; i < n; i++) {
2607       print_recorded_oop(log_n, i);
2608     }
2609   } else {
2610     tty->print_cr(" <list empty>");
2611   }
2612 }
2613 
2614 void nmethod::print_recorded_metadata() {
2615   const int n = metadata_count();
2616   const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
2617   tty->print("Recorded metadata:");
2618   if (n > 0) {
2619     tty->cr();
2620     for (int i = 0; i < n; i++) {
2621       Metadata* m = metadata_at(i);
2622       tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(m));
2623       if (m == (Metadata*)Universe::non_oop_word()) {
2624         tty->print("non-metadata word");
2625       } else if (m == nullptr) {
2626         tty->print("nullptr-oop");
2627       } else {
2628         Metadata::print_value_on_maybe_null(tty, m);
2629       }
2630       tty->cr();
2631     }
2632   } else {
2633     tty->print_cr(" <list empty>");
2634   }
2635 }
2636 #endif
2637 
2638 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
2639 
2640 void nmethod::print_constant_pool(outputStream* st) {
2641   //-----------------------------------
2642   //---<  Print the constant pool  >---
2643   //-----------------------------------
2644   int consts_size = this->consts_size();
2645   if ( consts_size > 0 ) {
2646     unsigned char* cstart = this->consts_begin();
2647     unsigned char* cp     = cstart;
2648     unsigned char* cend   = cp + consts_size;
2649     unsigned int   bytes_per_line = 4;
2650     unsigned int   CP_alignment   = 8;
2651     unsigned int   n;
2652 
2653     st->cr();
2654 
2655     //---<  print CP header to make clear what's printed  >---
2656     if( ((uintptr_t)cp&(CP_alignment-1)) == 0 ) {
2657       n = bytes_per_line;
2658       st->print_cr("[Constant Pool]");
2659       Disassembler::print_location(cp, cstart, cend, st, true, true);
2660       Disassembler::print_hexdata(cp, n, st, true);
2661       st->cr();
2662     } else {
2663       n = (int)((uintptr_t)cp & (bytes_per_line-1));
2664       st->print_cr("[Constant Pool (unaligned)]");
2665     }
2666 
2667     //---<  print CP contents, bytes_per_line at a time  >---
2668     while (cp < cend) {
2669       Disassembler::print_location(cp, cstart, cend, st, true, false);
2670       Disassembler::print_hexdata(cp, n, st, false);
2671       cp += n;
2672       n   = bytes_per_line;
2673       st->cr();
2674     }
2675 
2676     //---<  Show potential alignment gap between constant pool and code  >---
2677     cend = code_begin();
2678     if( cp < cend ) {
2679       n = 4;
2680       st->print_cr("[Code entry alignment]");
2681       while (cp < cend) {
2682         Disassembler::print_location(cp, cstart, cend, st, false, false);
2683         cp += n;
2684         st->cr();
2685       }
2686     }
2687   } else {
2688     st->print_cr("[Constant Pool (empty)]");
2689   }
2690   st->cr();
2691 }
2692 
2693 #endif
2694 
2695 // Disassemble this nmethod.
2696 // Print additional debug information, if requested. This could be code
2697 // comments, block comments, profiling counters, etc.
2698 // The undisassembled format is useful no disassembler library is available.
2699 // The resulting hex dump (with markers) can be disassembled later, or on
2700 // another system, when/where a disassembler library is available.
2701 void nmethod::decode2(outputStream* ost) const {
2702 
2703   // Called from frame::back_trace_with_decode without ResourceMark.
2704   ResourceMark rm;
2705 
2706   // Make sure we have a valid stream to print on.
2707   outputStream* st = ost ? ost : tty;
2708 
2709 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) && ! defined(SUPPORT_ASSEMBLY)
2710   const bool use_compressed_format    = true;
2711   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
2712                                                                   AbstractDisassembler::show_block_comment());
2713 #else
2714   const bool use_compressed_format    = Disassembler::is_abstract();
2715   const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
2716                                                                   AbstractDisassembler::show_block_comment());
2717 #endif
2718 
2719   st->cr();
2720   this->print(st);
2721   st->cr();
2722 
2723 #if defined(SUPPORT_ASSEMBLY)
2724   //----------------------------------
2725   //---<  Print real disassembly  >---
2726   //----------------------------------
2727   if (! use_compressed_format) {
2728     st->print_cr("[Disassembly]");
2729     Disassembler::decode(const_cast<nmethod*>(this), st);
2730     st->bol();
2731     st->print_cr("[/Disassembly]");
2732     return;
2733   }
2734 #endif
2735 
2736 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
2737 
2738   // Compressed undisassembled disassembly format.
2739   // The following status values are defined/supported:
2740   //   = 0 - currently at bol() position, nothing printed yet on current line.
2741   //   = 1 - currently at position after print_location().
2742   //   > 1 - in the midst of printing instruction stream bytes.
2743   int        compressed_format_idx    = 0;
2744   int        code_comment_column      = 0;
2745   const int  instr_maxlen             = Assembler::instr_maxlen();
2746   const uint tabspacing               = 8;
2747   unsigned char* start = this->code_begin();
2748   unsigned char* p     = this->code_begin();
2749   unsigned char* end   = this->code_end();
2750   unsigned char* pss   = p; // start of a code section (used for offsets)
2751 
2752   if ((start == nullptr) || (end == nullptr)) {
2753     st->print_cr("PrintAssembly not possible due to uninitialized section pointers");
2754     return;
2755   }
2756 #endif
2757 
2758 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
2759   //---<  plain abstract disassembly, no comments or anything, just section headers  >---
2760   if (use_compressed_format && ! compressed_with_comments) {
2761     const_cast<nmethod*>(this)->print_constant_pool(st);
2762 
2763     //---<  Open the output (Marker for post-mortem disassembler)  >---
2764     st->print_cr("[MachCode]");
2765     const char* header = nullptr;
2766     address p0 = p;
2767     while (p < end) {
2768       address pp = p;
2769       while ((p < end) && (header == nullptr)) {
2770         header = nmethod_section_label(p);
2771         pp  = p;
2772         p  += Assembler::instr_len(p);
2773       }
2774       if (pp > p0) {
2775         AbstractDisassembler::decode_range_abstract(p0, pp, start, end, st, Assembler::instr_maxlen());
2776         p0 = pp;
2777         p  = pp;
2778         header = nullptr;
2779       } else if (header != nullptr) {
2780         st->bol();
2781         st->print_cr("%s", header);
2782         header = nullptr;
2783       }
2784     }
2785     //---<  Close the output (Marker for post-mortem disassembler)  >---
2786     st->bol();
2787     st->print_cr("[/MachCode]");
2788     return;
2789   }
2790 #endif
2791 
2792 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
2793   //---<  abstract disassembly with comments and section headers merged in  >---
2794   if (compressed_with_comments) {
2795     const_cast<nmethod*>(this)->print_constant_pool(st);
2796 
2797     //---<  Open the output (Marker for post-mortem disassembler)  >---
2798     st->print_cr("[MachCode]");
2799     while ((p < end) && (p != nullptr)) {
2800       const int instruction_size_in_bytes = Assembler::instr_len(p);
2801 
2802       //---<  Block comments for nmethod. Interrupts instruction stream, if any.  >---
2803       // Outputs a bol() before and a cr() after, but only if a comment is printed.
2804       // Prints nmethod_section_label as well.
2805       if (AbstractDisassembler::show_block_comment()) {
2806         print_block_comment(st, p);
2807         if (st->position() == 0) {
2808           compressed_format_idx = 0;
2809         }
2810       }
2811 
2812       //---<  New location information after line break  >---
2813       if (compressed_format_idx == 0) {
2814         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
2815         compressed_format_idx = 1;
2816       }
2817 
2818       //---<  Code comment for current instruction. Address range [p..(p+len))  >---
2819       unsigned char* p_end = p + (ssize_t)instruction_size_in_bytes;
2820       S390_ONLY(if (p_end > end) p_end = end;) // avoid getting past the end
2821 
2822       if (AbstractDisassembler::show_comment() && const_cast<nmethod*>(this)->has_code_comment(p, p_end)) {
2823         //---<  interrupt instruction byte stream for code comment  >---
2824         if (compressed_format_idx > 1) {
2825           st->cr();  // interrupt byte stream
2826           st->cr();  // add an empty line
2827           code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
2828         }
2829         const_cast<nmethod*>(this)->print_code_comment_on(st, code_comment_column, p, p_end );
2830         st->bol();
2831         compressed_format_idx = 0;
2832       }
2833 
2834       //---<  New location information after line break  >---
2835       if (compressed_format_idx == 0) {
2836         code_comment_column   = Disassembler::print_location(p, pss, end, st, false, false);
2837         compressed_format_idx = 1;
2838       }
2839 
2840       //---<  Nicely align instructions for readability  >---
2841       if (compressed_format_idx > 1) {
2842         Disassembler::print_delimiter(st);
2843       }
2844 
2845       //---<  Now, finally, print the actual instruction bytes  >---
2846       unsigned char* p0 = p;
2847       p = Disassembler::decode_instruction_abstract(p, st, instruction_size_in_bytes, instr_maxlen);
2848       compressed_format_idx += (int)(p - p0);
2849 
2850       if (Disassembler::start_newline(compressed_format_idx-1)) {
2851         st->cr();
2852         compressed_format_idx = 0;
2853       }
2854     }
2855     //---<  Close the output (Marker for post-mortem disassembler)  >---
2856     st->bol();
2857     st->print_cr("[/MachCode]");
2858     return;
2859   }
2860 #endif
2861 }
2862 
2863 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
2864 
2865 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2866   RelocIterator iter(this, begin, end);
2867   bool have_one = false;
2868   while (iter.next()) {
2869     have_one = true;
2870     switch (iter.type()) {
2871         case relocInfo::none:                  return "no_reloc";
2872         case relocInfo::oop_type: {
2873           // Get a non-resizable resource-allocated stringStream.
2874           // Our callees make use of (nested) ResourceMarks.
2875           stringStream st(NEW_RESOURCE_ARRAY(char, 1024), 1024);
2876           oop_Relocation* r = iter.oop_reloc();
2877           oop obj = r->oop_value();
2878           st.print("oop(");
2879           if (obj == nullptr) st.print("nullptr");
2880           else obj->print_value_on(&st);
2881           st.print(")");
2882           return st.as_string();
2883         }
2884         case relocInfo::metadata_type: {
2885           stringStream st;
2886           metadata_Relocation* r = iter.metadata_reloc();
2887           Metadata* obj = r->metadata_value();
2888           st.print("metadata(");
2889           if (obj == nullptr) st.print("nullptr");
2890           else obj->print_value_on(&st);
2891           st.print(")");
2892           return st.as_string();
2893         }
2894         case relocInfo::runtime_call_type:
2895         case relocInfo::runtime_call_w_cp_type: {
2896           stringStream st;
2897           st.print("runtime_call");
2898           CallRelocation* r = (CallRelocation*)iter.reloc();
2899           address dest = r->destination();
2900           CodeBlob* cb = CodeCache::find_blob(dest);
2901           if (cb != nullptr) {
2902             st.print(" %s", cb->name());
2903           } else {
2904             ResourceMark rm;
2905             const int buflen = 1024;
2906             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
2907             int offset;
2908             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
2909               st.print(" %s", buf);
2910               if (offset != 0) {
2911                 st.print("+%d", offset);
2912               }
2913             }
2914           }
2915           return st.as_string();
2916         }
2917         case relocInfo::virtual_call_type: {
2918           stringStream st;
2919           st.print_raw("virtual_call");
2920           virtual_call_Relocation* r = iter.virtual_call_reloc();
2921           Method* m = r->method_value();
2922           if (m != nullptr) {
2923             assert(m->is_method(), "");
2924             m->print_short_name(&st);
2925           }
2926           return st.as_string();
2927         }
2928         case relocInfo::opt_virtual_call_type: {
2929           stringStream st;
2930           st.print_raw("optimized virtual_call");
2931           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
2932           Method* m = r->method_value();
2933           if (m != nullptr) {
2934             assert(m->is_method(), "");
2935             m->print_short_name(&st);
2936           }
2937           return st.as_string();
2938         }
2939         case relocInfo::static_call_type: {
2940           stringStream st;
2941           st.print_raw("static_call");
2942           static_call_Relocation* r = iter.static_call_reloc();
2943           Method* m = r->method_value();
2944           if (m != nullptr) {
2945             assert(m->is_method(), "");
2946             m->print_short_name(&st);
2947           }
2948           return st.as_string();
2949         }
2950         case relocInfo::static_stub_type:      return "static_stub";
2951         case relocInfo::external_word_type:    return "external_word";
2952         case relocInfo::internal_word_type:    return "internal_word";
2953         case relocInfo::section_word_type:     return "section_word";
2954         case relocInfo::poll_type:             return "poll";
2955         case relocInfo::poll_return_type:      return "poll_return";
2956         case relocInfo::trampoline_stub_type:  return "trampoline_stub";
2957         case relocInfo::type_mask:             return "type_bit_mask";
2958 
2959         default:
2960           break;
2961     }
2962   }
2963   return have_one ? "other" : nullptr;
2964 }
2965 
2966 // Return the last scope in (begin..end]
2967 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2968   PcDesc* p = pc_desc_near(begin+1);
2969   if (p != nullptr && p->real_pc(this) <= end) {
2970     return new ScopeDesc(this, p);
2971   }
2972   return nullptr;
2973 }
2974 
2975 const char* nmethod::nmethod_section_label(address pos) const {
2976   const char* label = nullptr;
2977   if (pos == code_begin())                                              label = "[Instructions begin]";
2978   if (pos == entry_point())                                             label = "[Entry Point]";
2979   if (pos == inline_entry_point())                                      label = "[Inline Entry Point]";
2980   if (pos == verified_entry_point())                                    label = "[Verified Entry Point]";
2981   if (pos == verified_inline_entry_point())                             label = "[Verified Inline Entry Point]";
2982   if (pos == verified_inline_ro_entry_point())                          label = "[Verified Inline Entry Point (RO)]";
2983   if (has_method_handle_invokes() && (pos == deopt_mh_handler_begin())) label = "[Deopt MH Handler Code]";
2984   if (pos == consts_begin() && pos != insts_begin())                    label = "[Constants]";
2985   // Check stub_code before checking exception_handler or deopt_handler.
2986   if (pos == this->stub_begin())                                        label = "[Stub Code]";
2987   if (JVMCI_ONLY(_exception_offset >= 0 &&) pos == exception_begin())           label = "[Exception Handler]";
2988   if (JVMCI_ONLY(_deopt_handler_begin != nullptr &&) pos == deopt_handler_begin()) label = "[Deopt Handler Code]";
2989   return label;
2990 }
2991 
2992 static int maybe_print_entry_label(outputStream* stream, address pos, address entry, const char* label) {
2993   if (pos == entry) {
2994     stream->bol();
2995     stream->print_cr("%s", label);
2996     return 1;
2997   } else {
2998     return 0;
2999   }
3000 }
3001 
3002 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels) const {
3003   if (print_section_labels) {
3004     int n = 0;
3005     // Multiple entry points may be at the same position. Print them all.
3006     n += maybe_print_entry_label(stream, block_begin, entry_point(),                    "[Entry Point]");
3007     n += maybe_print_entry_label(stream, block_begin, inline_entry_point(),             "[Inline Entry Point]");
3008     n += maybe_print_entry_label(stream, block_begin, verified_entry_point(),           "[Verified Entry Point]");
3009     n += maybe_print_entry_label(stream, block_begin, verified_inline_entry_point(),    "[Verified Inline Entry Point]");
3010     n += maybe_print_entry_label(stream, block_begin, verified_inline_ro_entry_point(), "[Verified Inline Entry Point (RO)]");
3011     if (n == 0) {
3012       const char* label = nmethod_section_label(block_begin);
3013       if (label != nullptr) {
3014         stream->bol();
3015         stream->print_cr("%s", label);
3016       }
3017     }
3018   }
3019 
3020   Method* m = method();
3021   if (m == nullptr || is_osr_method()) {
3022     return;
3023   }
3024 
3025   // Print the name of the method (only once)
3026   address low = MIN4(entry_point(), verified_entry_point(), verified_inline_entry_point(), verified_inline_ro_entry_point());
3027   low = MIN2(low, inline_entry_point());
3028   assert(low != 0, "sanity");
3029   if (block_begin == low) {
3030     stream->print("  # ");
3031     m->print_value_on(stream);
3032     stream->cr();
3033   }
3034 
3035   // Print the arguments for the 3 types of verified entry points
3036   CompiledEntrySignature ces(m);
3037   ces.compute_calling_conventions(false);
3038   const GrowableArray<SigEntry>* sig_cc;
3039   const VMRegPair* regs;
3040   if (block_begin == verified_entry_point()) {
3041     sig_cc = ces.sig_cc();
3042     regs = ces.regs_cc();
3043   } else if (block_begin == verified_inline_entry_point()) {
3044     sig_cc = ces.sig();
3045     regs = ces.regs();
3046   } else if (block_begin == verified_inline_ro_entry_point()) {
3047     sig_cc = ces.sig_cc_ro();
3048     regs = ces.regs_cc_ro();
3049   } else {
3050     return;
3051   }
3052 
3053   bool has_this = !m->is_static();
3054   if (ces.has_inline_recv() && block_begin == verified_entry_point()) {
3055     // <this> argument is scalarized for verified_entry_point()
3056     has_this = false;
3057   }
3058   const char* spname = "sp"; // make arch-specific?
3059   int stack_slot_offset = this->frame_size() * wordSize;
3060   int tab1 = 14, tab2 = 24;
3061   int sig_index = 0;
3062   int arg_index = has_this ? -1 : 0;
3063   bool did_old_sp = false;
3064   for (ExtendedSignature sig = ExtendedSignature(sig_cc, SigEntryFilter()); !sig.at_end(); ++sig) {
3065     bool at_this = (arg_index == -1);
3066     bool at_old_sp = false;
3067     BasicType t = (*sig)._bt;
3068     if (at_this) {
3069       stream->print("  # this: ");
3070     } else {
3071       stream->print("  # parm%d: ", arg_index);
3072     }
3073     stream->move_to(tab1);
3074     VMReg fst = regs[sig_index].first();
3075     VMReg snd = regs[sig_index].second();
3076     if (fst->is_reg()) {
3077       stream->print("%s", fst->name());
3078       if (snd->is_valid())  {
3079         stream->print(":%s", snd->name());
3080       }
3081     } else if (fst->is_stack()) {
3082       int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
3083       if (offset == stack_slot_offset)  at_old_sp = true;
3084       stream->print("[%s+0x%x]", spname, offset);
3085     } else {
3086       stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
3087     }
3088     stream->print(" ");
3089     stream->move_to(tab2);
3090     stream->print("= ");
3091     if (at_this) {
3092       m->method_holder()->print_value_on(stream);
3093     } else {
3094       bool did_name = false;
3095       if (is_reference_type(t)) {
3096         Symbol* name = (*sig)._symbol;
3097         name->print_value_on(stream);
3098         did_name = true;
3099       }
3100       if (!did_name)
3101         stream->print("%s", type2name(t));
3102     }
3103     if (at_old_sp) {
3104       stream->print("  (%s of caller)", spname);
3105       did_old_sp = true;
3106     }
3107     stream->cr();
3108     sig_index += type2size[t];
3109     arg_index += 1;
3110   }
3111   if (!did_old_sp) {
3112     stream->print("  # ");
3113     stream->move_to(tab1);
3114     stream->print("[%s+0x%x]", spname, stack_slot_offset);
3115     stream->print("  (%s of caller)", spname);
3116     stream->cr();
3117   }
3118 }
3119 
3120 // Returns whether this nmethod has code comments.
3121 bool nmethod::has_code_comment(address begin, address end) {
3122   // scopes?
3123   ScopeDesc* sd  = scope_desc_in(begin, end);
3124   if (sd != nullptr) return true;
3125 
3126   // relocations?
3127   const char* str = reloc_string_for(begin, end);
3128   if (str != nullptr) return true;
3129 
3130   // implicit exceptions?
3131   int cont_offset = ImplicitExceptionTable(this).continuation_offset((uint)(begin - code_begin()));
3132   if (cont_offset != 0) return true;
3133 
3134   return false;
3135 }
3136 
3137 void nmethod::print_code_comment_on(outputStream* st, int column, address begin, address end) {
3138   ImplicitExceptionTable implicit_table(this);
3139   int pc_offset = (int)(begin - code_begin());
3140   int cont_offset = implicit_table.continuation_offset(pc_offset);
3141   bool oop_map_required = false;
3142   if (cont_offset != 0) {
3143     st->move_to(column, 6, 0);
3144     if (pc_offset == cont_offset) {
3145       st->print("; implicit exception: deoptimizes");
3146       oop_map_required = true;
3147     } else {
3148       st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
3149     }
3150   }
3151 
3152   // Find an oopmap in (begin, end].  We use the odd half-closed
3153   // interval so that oop maps and scope descs which are tied to the
3154   // byte after a call are printed with the call itself.  OopMaps
3155   // associated with implicit exceptions are printed with the implicit
3156   // instruction.
3157   address base = code_begin();
3158   ImmutableOopMapSet* oms = oop_maps();
3159   if (oms != nullptr) {
3160     for (int i = 0, imax = oms->count(); i < imax; i++) {
3161       const ImmutableOopMapPair* pair = oms->pair_at(i);
3162       const ImmutableOopMap* om = pair->get_from(oms);
3163       address pc = base + pair->pc_offset();
3164       if (pc >= begin) {
3165 #if INCLUDE_JVMCI
3166         bool is_implicit_deopt = implicit_table.continuation_offset(pair->pc_offset()) == (uint) pair->pc_offset();
3167 #else
3168         bool is_implicit_deopt = false;
3169 #endif
3170         if (is_implicit_deopt ? pc == begin : pc > begin && pc <= end) {
3171           st->move_to(column, 6, 0);
3172           st->print("; ");
3173           om->print_on(st);
3174           oop_map_required = false;
3175         }
3176       }
3177       if (pc > end) {
3178         break;
3179       }
3180     }
3181   }
3182   assert(!oop_map_required, "missed oopmap");
3183 
3184   Thread* thread = Thread::current();
3185 
3186   // Print any debug info present at this pc.
3187   ScopeDesc* sd  = scope_desc_in(begin, end);
3188   if (sd != nullptr) {
3189     st->move_to(column, 6, 0);
3190     if (sd->bci() == SynchronizationEntryBCI) {
3191       st->print(";*synchronization entry");
3192     } else if (sd->bci() == AfterBci) {
3193       st->print(";* method exit (unlocked if synchronized)");
3194     } else if (sd->bci() == UnwindBci) {
3195       st->print(";* unwind (locked if synchronized)");
3196     } else if (sd->bci() == AfterExceptionBci) {
3197       st->print(";* unwind (unlocked if synchronized)");
3198     } else if (sd->bci() == UnknownBci) {
3199       st->print(";* unknown");
3200     } else if (sd->bci() == InvalidFrameStateBci) {
3201       st->print(";* invalid frame state");
3202     } else {
3203       if (sd->method() == nullptr) {
3204         st->print("method is nullptr");
3205       } else if (sd->method()->is_native()) {
3206         st->print("method is native");
3207       } else {
3208         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
3209         st->print(";*%s", Bytecodes::name(bc));
3210         switch (bc) {
3211         case Bytecodes::_invokevirtual:
3212         case Bytecodes::_invokespecial:
3213         case Bytecodes::_invokestatic:
3214         case Bytecodes::_invokeinterface:
3215           {
3216             Bytecode_invoke invoke(methodHandle(thread, sd->method()), sd->bci());
3217             st->print(" ");
3218             if (invoke.name() != nullptr)
3219               invoke.name()->print_symbol_on(st);
3220             else
3221               st->print("<UNKNOWN>");
3222             break;
3223           }
3224         case Bytecodes::_getfield:
3225         case Bytecodes::_putfield:
3226         case Bytecodes::_getstatic:
3227         case Bytecodes::_putstatic:
3228           {
3229             Bytecode_field field(methodHandle(thread, sd->method()), sd->bci());
3230             st->print(" ");
3231             if (field.name() != nullptr)
3232               field.name()->print_symbol_on(st);
3233             else
3234               st->print("<UNKNOWN>");
3235           }
3236         default:
3237           break;
3238         }
3239       }
3240       st->print(" {reexecute=%d rethrow=%d return_oop=%d return_scalarized=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop(), sd->return_scalarized());
3241     }
3242 
3243     // Print all scopes
3244     for (;sd != nullptr; sd = sd->sender()) {
3245       st->move_to(column, 6, 0);
3246       st->print("; -");
3247       if (sd->should_reexecute()) {
3248         st->print(" (reexecute)");
3249       }
3250       if (sd->method() == nullptr) {
3251         st->print("method is nullptr");
3252       } else {
3253         sd->method()->print_short_name(st);
3254       }
3255       int lineno = sd->method()->line_number_from_bci(sd->bci());
3256       if (lineno != -1) {
3257         st->print("@%d (line %d)", sd->bci(), lineno);
3258       } else {
3259         st->print("@%d", sd->bci());
3260       }
3261       st->cr();
3262     }
3263   }
3264 
3265   // Print relocation information
3266   // Prevent memory leak: allocating without ResourceMark.
3267   ResourceMark rm;
3268   const char* str = reloc_string_for(begin, end);
3269   if (str != nullptr) {
3270     if (sd != nullptr) st->cr();
3271     st->move_to(column, 6, 0);
3272     st->print(";   {%s}", str);
3273   }
3274 }
3275 
3276 #endif
3277 
3278 class DirectNativeCallWrapper: public NativeCallWrapper {
3279 private:
3280   NativeCall* _call;
3281 
3282 public:
3283   DirectNativeCallWrapper(NativeCall* call) : _call(call) {}
3284 
3285   virtual address destination() const { return _call->destination(); }
3286   virtual address instruction_address() const { return _call->instruction_address(); }
3287   virtual address next_instruction_address() const { return _call->next_instruction_address(); }
3288   virtual address return_address() const { return _call->return_address(); }
3289 
3290   virtual address get_resolve_call_stub(bool is_optimized) const {
3291     if (is_optimized) {
3292       return SharedRuntime::get_resolve_opt_virtual_call_stub();
3293     }
3294     return SharedRuntime::get_resolve_virtual_call_stub();
3295   }
3296 
3297   virtual void set_destination_mt_safe(address dest) {
3298     _call->set_destination_mt_safe(dest);
3299   }
3300 
3301   virtual void set_to_interpreted(const methodHandle& method, CompiledICInfo& info) {
3302     CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
3303     {
3304       csc->set_to_interpreted(method, info.entry());
3305     }
3306   }
3307 
3308   virtual void verify() const {
3309     // make sure code pattern is actually a call imm32 instruction
3310     _call->verify();
3311     _call->verify_alignment();
3312   }
3313 
3314   virtual void verify_resolve_call(address dest) const {
3315     CodeBlob* db = CodeCache::find_blob(dest);
3316     assert(db != nullptr && !db->is_adapter_blob(), "must use stub!");
3317   }
3318 
3319   virtual bool is_call_to_interpreted(address dest) const {
3320     CodeBlob* cb = CodeCache::find_blob(_call->instruction_address());
3321     return cb->contains(dest);
3322   }
3323 
3324   virtual bool is_safe_for_patching() const { return false; }
3325 
3326   virtual NativeInstruction* get_load_instruction(virtual_call_Relocation* r) const {
3327     return nativeMovConstReg_at(r->cached_value());
3328   }
3329 
3330   virtual void *get_data(NativeInstruction* instruction) const {
3331     return (void*)((NativeMovConstReg*) instruction)->data();
3332   }
3333 
3334   virtual void set_data(NativeInstruction* instruction, intptr_t data) {
3335     ((NativeMovConstReg*) instruction)->set_data(data);
3336   }
3337 };
3338 
3339 NativeCallWrapper* nmethod::call_wrapper_at(address call) const {
3340   return new DirectNativeCallWrapper((NativeCall*) call);
3341 }
3342 
3343 NativeCallWrapper* nmethod::call_wrapper_before(address return_pc) const {
3344   return new DirectNativeCallWrapper(nativeCall_before(return_pc));
3345 }
3346 
3347 address nmethod::call_instruction_address(address pc) const {
3348   if (NativeCall::is_call_before(pc)) {
3349     NativeCall *ncall = nativeCall_before(pc);
3350     return ncall->instruction_address();
3351   }
3352   return nullptr;
3353 }
3354 
3355 CompiledStaticCall* nmethod::compiledStaticCall_at(Relocation* call_site) const {
3356   return CompiledDirectStaticCall::at(call_site);
3357 }
3358 
3359 CompiledStaticCall* nmethod::compiledStaticCall_at(address call_site) const {
3360   return CompiledDirectStaticCall::at(call_site);
3361 }
3362 
3363 CompiledStaticCall* nmethod::compiledStaticCall_before(address return_addr) const {
3364   return CompiledDirectStaticCall::before(return_addr);
3365 }
3366 
3367 #if defined(SUPPORT_DATA_STRUCTS)
3368 void nmethod::print_value_on(outputStream* st) const {
3369   st->print("nmethod");
3370   print_on(st, nullptr);
3371 }
3372 #endif
3373 
3374 #ifndef PRODUCT
3375 
3376 void nmethod::print_calls(outputStream* st) {
3377   RelocIterator iter(this);
3378   while (iter.next()) {
3379     switch (iter.type()) {
3380     case relocInfo::virtual_call_type:
3381     case relocInfo::opt_virtual_call_type: {
3382       CompiledICLocker ml_verify(this);
3383       CompiledIC_at(&iter)->print();
3384       break;
3385     }
3386     case relocInfo::static_call_type:
3387       st->print_cr("Static call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
3388       CompiledDirectStaticCall::at(iter.reloc())->print();
3389       break;
3390     default:
3391       break;
3392     }
3393   }
3394 }
3395 
3396 void nmethod::print_statistics() {
3397   ttyLocker ttyl;
3398   if (xtty != nullptr)  xtty->head("statistics type='nmethod'");
3399   native_nmethod_stats.print_native_nmethod_stats();
3400 #ifdef COMPILER1
3401   c1_java_nmethod_stats.print_nmethod_stats("C1");
3402 #endif
3403 #ifdef COMPILER2
3404   c2_java_nmethod_stats.print_nmethod_stats("C2");
3405 #endif
3406 #if INCLUDE_JVMCI
3407   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
3408 #endif
3409   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
3410   DebugInformationRecorder::print_statistics();
3411 #ifndef PRODUCT
3412   pc_nmethod_stats.print_pc_stats();
3413 #endif
3414   Dependencies::print_statistics();
3415   if (xtty != nullptr)  xtty->tail("statistics");
3416 }
3417 
3418 #endif // !PRODUCT
3419 
3420 #if INCLUDE_JVMCI
3421 void nmethod::update_speculation(JavaThread* thread) {
3422   jlong speculation = thread->pending_failed_speculation();
3423   if (speculation != 0) {
3424     guarantee(jvmci_nmethod_data() != nullptr, "failed speculation in nmethod without failed speculation list");
3425     jvmci_nmethod_data()->add_failed_speculation(this, speculation);
3426     thread->set_pending_failed_speculation(0);
3427   }
3428 }
3429 
3430 const char* nmethod::jvmci_name() {
3431   if (jvmci_nmethod_data() != nullptr) {
3432     return jvmci_nmethod_data()->name();
3433   }
3434   return nullptr;
3435 }
3436 #endif