1 /*
   2  * Copyright (c) 1997, 2018, 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 "jvm.h"
  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/compileBroker.hpp"
  36 #include "compiler/compileLog.hpp"
  37 #include "compiler/compilerDirectives.hpp"
  38 #include "compiler/directivesParser.hpp"
  39 #include "compiler/disassembler.hpp"
  40 #include "interpreter/bytecode.hpp"
  41 #include "logging/log.hpp"
  42 #include "logging/logStream.hpp"
  43 #include "memory/allocation.inline.hpp"
  44 #include "memory/resourceArea.hpp"
  45 #include "oops/method.inline.hpp"
  46 #include "oops/methodData.hpp"
  47 #include "oops/oop.inline.hpp"
  48 #include "prims/jvmtiImpl.hpp"
  49 #include "runtime/atomic.hpp"
  50 #include "runtime/flags/flagSetting.hpp"
  51 #include "runtime/frame.inline.hpp"
  52 #include "runtime/handles.inline.hpp"
  53 #include "runtime/jniHandles.inline.hpp"
  54 #include "runtime/orderAccess.hpp"
  55 #include "runtime/os.hpp"
  56 #include "runtime/safepointVerifiers.hpp"
  57 #include "runtime/sharedRuntime.hpp"
  58 #include "runtime/sweeper.hpp"
  59 #include "runtime/vmThread.hpp"
  60 #include "utilities/align.hpp"
  61 #include "utilities/dtrace.hpp"
  62 #include "utilities/events.hpp"
  63 #include "utilities/resourceHash.hpp"
  64 #include "utilities/xmlstream.hpp"
  65 #if INCLUDE_JVMCI
  66 #include "jvmci/jvmciJavaClasses.hpp"
  67 #endif
  68 
  69 #ifdef DTRACE_ENABLED
  70 
  71 // Only bother with this argument setup if dtrace is available
  72 
  73 #define DTRACE_METHOD_UNLOAD_PROBE(method)                                \
  74   {                                                                       \
  75     Method* m = (method);                                                 \
  76     if (m != NULL) {                                                      \
  77       Symbol* klass_name = m->klass_name();                               \
  78       Symbol* name = m->name();                                           \
  79       Symbol* signature = m->signature();                                 \
  80       HOTSPOT_COMPILED_METHOD_UNLOAD(                                     \
  81         (char *) klass_name->bytes(), klass_name->utf8_length(),                   \
  82         (char *) name->bytes(), name->utf8_length(),                               \
  83         (char *) signature->bytes(), signature->utf8_length());                    \
  84     }                                                                     \
  85   }
  86 
  87 #else //  ndef DTRACE_ENABLED
  88 
  89 #define DTRACE_METHOD_UNLOAD_PROBE(method)
  90 
  91 #endif
  92 
  93 //---------------------------------------------------------------------------------
  94 // NMethod statistics
  95 // They are printed under various flags, including:
  96 //   PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
  97 // (In the latter two cases, they like other stats are printed to the log only.)
  98 
  99 #ifndef PRODUCT
 100 // These variables are put into one block to reduce relocations
 101 // and make it simpler to print from the debugger.
 102 struct java_nmethod_stats_struct {
 103   int nmethod_count;
 104   int total_size;
 105   int relocation_size;
 106   int consts_size;
 107   int insts_size;
 108   int stub_size;
 109   int scopes_data_size;
 110   int scopes_pcs_size;
 111   int dependencies_size;
 112   int handler_table_size;
 113   int nul_chk_table_size;
 114   int oops_size;
 115   int metadata_size;
 116 
 117   void note_nmethod(nmethod* nm) {
 118     nmethod_count += 1;
 119     total_size          += nm->size();
 120     relocation_size     += nm->relocation_size();
 121     consts_size         += nm->consts_size();
 122     insts_size          += nm->insts_size();
 123     stub_size           += nm->stub_size();
 124     oops_size           += nm->oops_size();
 125     metadata_size       += nm->metadata_size();
 126     scopes_data_size    += nm->scopes_data_size();
 127     scopes_pcs_size     += nm->scopes_pcs_size();
 128     dependencies_size   += nm->dependencies_size();
 129     handler_table_size  += nm->handler_table_size();
 130     nul_chk_table_size  += nm->nul_chk_table_size();
 131   }
 132   void print_nmethod_stats(const char* name) {
 133     if (nmethod_count == 0)  return;
 134     tty->print_cr("Statistics for %d bytecoded nmethods for %s:", nmethod_count, name);
 135     if (total_size != 0)          tty->print_cr(" total in heap  = %d", total_size);
 136     if (nmethod_count != 0)       tty->print_cr(" header         = " SIZE_FORMAT, nmethod_count * sizeof(nmethod));
 137     if (relocation_size != 0)     tty->print_cr(" relocation     = %d", relocation_size);
 138     if (consts_size != 0)         tty->print_cr(" constants      = %d", consts_size);
 139     if (insts_size != 0)          tty->print_cr(" main code      = %d", insts_size);
 140     if (stub_size != 0)           tty->print_cr(" stub code      = %d", stub_size);
 141     if (oops_size != 0)           tty->print_cr(" oops           = %d", oops_size);
 142     if (metadata_size != 0)       tty->print_cr(" metadata       = %d", metadata_size);
 143     if (scopes_data_size != 0)    tty->print_cr(" scopes data    = %d", scopes_data_size);
 144     if (scopes_pcs_size != 0)     tty->print_cr(" scopes pcs     = %d", scopes_pcs_size);
 145     if (dependencies_size != 0)   tty->print_cr(" dependencies   = %d", dependencies_size);
 146     if (handler_table_size != 0)  tty->print_cr(" handler table  = %d", handler_table_size);
 147     if (nul_chk_table_size != 0)  tty->print_cr(" nul chk table  = %d", nul_chk_table_size);
 148   }
 149 };
 150 
 151 struct native_nmethod_stats_struct {
 152   int native_nmethod_count;
 153   int native_total_size;
 154   int native_relocation_size;
 155   int native_insts_size;
 156   int native_oops_size;
 157   int native_metadata_size;
 158   void note_native_nmethod(nmethod* nm) {
 159     native_nmethod_count += 1;
 160     native_total_size       += nm->size();
 161     native_relocation_size  += nm->relocation_size();
 162     native_insts_size       += nm->insts_size();
 163     native_oops_size        += nm->oops_size();
 164     native_metadata_size    += nm->metadata_size();
 165   }
 166   void print_native_nmethod_stats() {
 167     if (native_nmethod_count == 0)  return;
 168     tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
 169     if (native_total_size != 0)       tty->print_cr(" N. total size  = %d", native_total_size);
 170     if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %d", native_relocation_size);
 171     if (native_insts_size != 0)       tty->print_cr(" N. main code   = %d", native_insts_size);
 172     if (native_oops_size != 0)        tty->print_cr(" N. oops        = %d", native_oops_size);
 173     if (native_metadata_size != 0)    tty->print_cr(" N. metadata    = %d", native_metadata_size);
 174   }
 175 };
 176 
 177 struct pc_nmethod_stats_struct {
 178   int pc_desc_resets;   // number of resets (= number of caches)
 179   int pc_desc_queries;  // queries to nmethod::find_pc_desc
 180   int pc_desc_approx;   // number of those which have approximate true
 181   int pc_desc_repeats;  // number of _pc_descs[0] hits
 182   int pc_desc_hits;     // number of LRU cache hits
 183   int pc_desc_tests;    // total number of PcDesc examinations
 184   int pc_desc_searches; // total number of quasi-binary search steps
 185   int pc_desc_adds;     // number of LUR cache insertions
 186 
 187   void print_pc_stats() {
 188     tty->print_cr("PcDesc Statistics:  %d queries, %.2f comparisons per query",
 189                   pc_desc_queries,
 190                   (double)(pc_desc_tests + pc_desc_searches)
 191                   / pc_desc_queries);
 192     tty->print_cr("  caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
 193                   pc_desc_resets,
 194                   pc_desc_queries, pc_desc_approx,
 195                   pc_desc_repeats, pc_desc_hits,
 196                   pc_desc_tests, pc_desc_searches, pc_desc_adds);
 197   }
 198 };
 199 
 200 #ifdef COMPILER1
 201 static java_nmethod_stats_struct c1_java_nmethod_stats;
 202 #endif
 203 #ifdef COMPILER2
 204 static java_nmethod_stats_struct c2_java_nmethod_stats;
 205 #endif
 206 #if INCLUDE_JVMCI
 207 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
 208 #endif
 209 static java_nmethod_stats_struct unknown_java_nmethod_stats;
 210 
 211 static native_nmethod_stats_struct native_nmethod_stats;
 212 static pc_nmethod_stats_struct pc_nmethod_stats;
 213 
 214 static void note_java_nmethod(nmethod* nm) {
 215 #ifdef COMPILER1
 216   if (nm->is_compiled_by_c1()) {
 217     c1_java_nmethod_stats.note_nmethod(nm);
 218   } else
 219 #endif
 220 #ifdef COMPILER2
 221   if (nm->is_compiled_by_c2()) {
 222     c2_java_nmethod_stats.note_nmethod(nm);
 223   } else
 224 #endif
 225 #if INCLUDE_JVMCI
 226   if (nm->is_compiled_by_jvmci()) {
 227     jvmci_java_nmethod_stats.note_nmethod(nm);
 228   } else
 229 #endif
 230   {
 231     unknown_java_nmethod_stats.note_nmethod(nm);
 232   }
 233 }
 234 #endif // !PRODUCT
 235 
 236 //---------------------------------------------------------------------------------
 237 
 238 
 239 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
 240   assert(pc != NULL, "Must be non null");
 241   assert(exception.not_null(), "Must be non null");
 242   assert(handler != NULL, "Must be non null");
 243 
 244   _count = 0;
 245   _exception_type = exception->klass();
 246   _next = NULL;
 247 
 248   add_address_and_handler(pc,handler);
 249 }
 250 
 251 
 252 address ExceptionCache::match(Handle exception, address pc) {
 253   assert(pc != NULL,"Must be non null");
 254   assert(exception.not_null(),"Must be non null");
 255   if (exception->klass() == exception_type()) {
 256     return (test_address(pc));
 257   }
 258 
 259   return NULL;
 260 }
 261 
 262 
 263 bool ExceptionCache::match_exception_with_space(Handle exception) {
 264   assert(exception.not_null(),"Must be non null");
 265   if (exception->klass() == exception_type() && count() < cache_size) {
 266     return true;
 267   }
 268   return false;
 269 }
 270 
 271 
 272 address ExceptionCache::test_address(address addr) {
 273   int limit = count();
 274   for (int i = 0; i < limit; i++) {
 275     if (pc_at(i) == addr) {
 276       return handler_at(i);
 277     }
 278   }
 279   return NULL;
 280 }
 281 
 282 
 283 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
 284   if (test_address(addr) == handler) return true;
 285 
 286   int index = count();
 287   if (index < cache_size) {
 288     set_pc_at(index, addr);
 289     set_handler_at(index, handler);
 290     increment_count();
 291     return true;
 292   }
 293   return false;
 294 }
 295 
 296 //-----------------------------------------------------------------------------
 297 
 298 
 299 // Helper used by both find_pc_desc methods.
 300 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
 301   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
 302   if (!approximate)
 303     return pc->pc_offset() == pc_offset;
 304   else
 305     return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
 306 }
 307 
 308 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
 309   if (initial_pc_desc == NULL) {
 310     _pc_descs[0] = NULL; // native method; no PcDescs at all
 311     return;
 312   }
 313   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_resets);
 314   // reset the cache by filling it with benign (non-null) values
 315   assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
 316   for (int i = 0; i < cache_size; i++)
 317     _pc_descs[i] = initial_pc_desc;
 318 }
 319 
 320 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
 321   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_queries);
 322   NOT_PRODUCT(if (approximate) ++pc_nmethod_stats.pc_desc_approx);
 323 
 324   // Note: one might think that caching the most recently
 325   // read value separately would be a win, but one would be
 326   // wrong.  When many threads are updating it, the cache
 327   // line it's in would bounce between caches, negating
 328   // any benefit.
 329 
 330   // In order to prevent race conditions do not load cache elements
 331   // repeatedly, but use a local copy:
 332   PcDesc* res;
 333 
 334   // Step one:  Check the most recently added value.
 335   res = _pc_descs[0];
 336   if (res == NULL) return NULL;  // native method; no PcDescs at all
 337   if (match_desc(res, pc_offset, approximate)) {
 338     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
 339     return res;
 340   }
 341 
 342   // Step two:  Check the rest of the LRU cache.
 343   for (int i = 1; i < cache_size; ++i) {
 344     res = _pc_descs[i];
 345     if (res->pc_offset() < 0) break;  // optimization: skip empty cache
 346     if (match_desc(res, pc_offset, approximate)) {
 347       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
 348       return res;
 349     }
 350   }
 351 
 352   // Report failure.
 353   return NULL;
 354 }
 355 
 356 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
 357   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
 358   // Update the LRU cache by shifting pc_desc forward.
 359   for (int i = 0; i < cache_size; i++)  {
 360     PcDesc* next = _pc_descs[i];
 361     _pc_descs[i] = pc_desc;
 362     pc_desc = next;
 363   }
 364 }
 365 
 366 // adjust pcs_size so that it is a multiple of both oopSize and
 367 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
 368 // of oopSize, then 2*sizeof(PcDesc) is)
 369 static int adjust_pcs_size(int pcs_size) {
 370   int nsize = align_up(pcs_size,   oopSize);
 371   if ((nsize % sizeof(PcDesc)) != 0) {
 372     nsize = pcs_size + sizeof(PcDesc);
 373   }
 374   assert((nsize % oopSize) == 0, "correct alignment");
 375   return nsize;
 376 }
 377 
 378 
 379 int nmethod::total_size() const {
 380   return
 381     consts_size()        +
 382     insts_size()         +
 383     stub_size()          +
 384     scopes_data_size()   +
 385     scopes_pcs_size()    +
 386     handler_table_size() +
 387     nul_chk_table_size();
 388 }
 389 
 390 address* nmethod::orig_pc_addr(const frame* fr) {
 391   return (address*) ((address)fr->unextended_sp() + _orig_pc_offset);
 392 }
 393 
 394 const char* nmethod::compile_kind() const {
 395   if (is_osr_method())     return "osr";
 396   if (method() != NULL && is_native_method())  return "c2n";
 397   return NULL;
 398 }
 399 
 400 // Fill in default values for various flag fields
 401 void nmethod::init_defaults() {
 402   _state                      = not_installed;
 403   _has_flushed_dependencies   = 0;
 404   _lock_count                 = 0;
 405   _stack_traversal_mark       = 0;
 406   _unload_reported            = false; // jvmti state
 407   _is_far_code                = false; // nmethods are located in CodeCache
 408 
 409 #ifdef ASSERT
 410   _oops_are_stale             = false;
 411 #endif
 412 
 413   _oops_do_mark_link       = NULL;
 414   _jmethod_id              = NULL;
 415   _osr_link                = NULL;
 416   _unloading_next          = NULL;
 417   _scavenge_root_link      = NULL;
 418   _scavenge_root_state     = 0;
 419 #if INCLUDE_RTM_OPT
 420   _rtm_state               = NoRTM;
 421 #endif
 422 #if INCLUDE_JVMCI
 423   _jvmci_installed_code   = NULL;
 424   _speculation_log        = NULL;
 425   _jvmci_installed_code_triggers_invalidation = false;
 426 #endif
 427 }
 428 
 429 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
 430   int compile_id,
 431   CodeBuffer *code_buffer,
 432   int vep_offset,
 433   int frame_complete,
 434   int frame_size,
 435   ByteSize basic_lock_owner_sp_offset,
 436   ByteSize basic_lock_sp_offset,
 437   OopMapSet* oop_maps) {
 438   code_buffer->finalize_oop_references(method);
 439   // create nmethod
 440   nmethod* nm = NULL;
 441   {
 442     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 443     int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
 444     CodeOffsets offsets;
 445     offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
 446     offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
 447     nm = new (native_nmethod_size, CompLevel_none) nmethod(method(), compiler_none, native_nmethod_size,
 448                                             compile_id, &offsets,
 449                                             code_buffer, frame_size,
 450                                             basic_lock_owner_sp_offset,
 451                                             basic_lock_sp_offset, oop_maps);
 452     NOT_PRODUCT(if (nm != NULL)  native_nmethod_stats.note_native_nmethod(nm));
 453   }
 454 
 455   if (nm != NULL) {
 456     // verify nmethod
 457     debug_only(nm->verify();) // might block
 458 
 459     nm->log_new_nmethod();
 460     nm->make_in_use();
 461   }
 462   return nm;
 463 }
 464 
 465 nmethod* nmethod::new_nmethod(const methodHandle& method,
 466   int compile_id,
 467   int entry_bci,
 468   CodeOffsets* offsets,
 469   int orig_pc_offset,
 470   DebugInformationRecorder* debug_info,
 471   Dependencies* dependencies,
 472   CodeBuffer* code_buffer, int frame_size,
 473   OopMapSet* oop_maps,
 474   ExceptionHandlerTable* handler_table,
 475   ImplicitExceptionTable* nul_chk_table,
 476   AbstractCompiler* compiler,
 477   int comp_level
 478 #if INCLUDE_JVMCI
 479   , jweak installed_code,
 480   jweak speculationLog
 481 #endif
 482 )
 483 {
 484   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 485   code_buffer->finalize_oop_references(method);
 486   // create nmethod
 487   nmethod* nm = NULL;
 488   { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
 489     int nmethod_size =
 490       CodeBlob::allocation_size(code_buffer, sizeof(nmethod))
 491       + adjust_pcs_size(debug_info->pcs_size())
 492       + align_up((int)dependencies->size_in_bytes(), oopSize)
 493       + align_up(handler_table->size_in_bytes()    , oopSize)
 494       + align_up(nul_chk_table->size_in_bytes()    , oopSize)
 495       + align_up(debug_info->data_size()           , oopSize);
 496 
 497     nm = new (nmethod_size, comp_level)
 498     nmethod(method(), compiler->type(), nmethod_size, compile_id, entry_bci, offsets,
 499             orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
 500             oop_maps,
 501             handler_table,
 502             nul_chk_table,
 503             compiler,
 504             comp_level
 505 #if INCLUDE_JVMCI
 506             , installed_code,
 507             speculationLog
 508 #endif
 509             );
 510 
 511     if (nm != NULL) {
 512       // To make dependency checking during class loading fast, record
 513       // the nmethod dependencies in the classes it is dependent on.
 514       // This allows the dependency checking code to simply walk the
 515       // class hierarchy above the loaded class, checking only nmethods
 516       // which are dependent on those classes.  The slow way is to
 517       // check every nmethod for dependencies which makes it linear in
 518       // the number of methods compiled.  For applications with a lot
 519       // classes the slow way is too slow.
 520       for (Dependencies::DepStream deps(nm); deps.next(); ) {
 521         if (deps.type() == Dependencies::call_site_target_value) {
 522           // CallSite dependencies are managed on per-CallSite instance basis.
 523           oop call_site = deps.argument_oop(0);
 524           MethodHandles::add_dependent_nmethod(call_site, nm);
 525         } else {
 526           Klass* klass = deps.context_type();
 527           if (klass == NULL) {
 528             continue;  // ignore things like evol_method
 529           }
 530           // record this nmethod as dependent on this klass
 531           InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
 532         }
 533       }
 534       NOT_PRODUCT(if (nm != NULL)  note_java_nmethod(nm));
 535     }
 536   }
 537   // Do verification and logging outside CodeCache_lock.
 538   if (nm != NULL) {
 539     // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
 540     DEBUG_ONLY(nm->verify();)
 541     nm->log_new_nmethod();
 542   }
 543   return nm;
 544 }
 545 
 546 // For native wrappers
 547 nmethod::nmethod(
 548   Method* method,
 549   CompilerType type,
 550   int nmethod_size,
 551   int compile_id,
 552   CodeOffsets* offsets,
 553   CodeBuffer* code_buffer,
 554   int frame_size,
 555   ByteSize basic_lock_owner_sp_offset,
 556   ByteSize basic_lock_sp_offset,
 557   OopMapSet* oop_maps )
 558   : CompiledMethod(method, "native nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
 559   _native_receiver_sp_offset(basic_lock_owner_sp_offset),
 560   _native_basic_lock_sp_offset(basic_lock_sp_offset)
 561 {
 562   {
 563     int scopes_data_offset = 0;
 564     int deoptimize_offset       = 0;
 565     int deoptimize_mh_offset    = 0;
 566 
 567     debug_only(NoSafepointVerifier nsv;)
 568     assert_locked_or_safepoint(CodeCache_lock);
 569 
 570     init_defaults();
 571     _entry_bci               = InvocationEntryBci;
 572     // We have no exception handler or deopt handler make the
 573     // values something that will never match a pc like the nmethod vtable entry
 574     _exception_offset        = 0;
 575     _orig_pc_offset          = 0;
 576 
 577     _consts_offset           = data_offset();
 578     _stub_offset             = data_offset();
 579     _oops_offset             = data_offset();
 580     _metadata_offset         = _oops_offset         + align_up(code_buffer->total_oop_size(), oopSize);
 581     scopes_data_offset       = _metadata_offset     + align_up(code_buffer->total_metadata_size(), wordSize);
 582     _scopes_pcs_offset       = scopes_data_offset;
 583     _dependencies_offset     = _scopes_pcs_offset;
 584     _handler_table_offset    = _dependencies_offset;
 585     _nul_chk_table_offset    = _handler_table_offset;
 586     _nmethod_end_offset      = _nul_chk_table_offset;
 587     _compile_id              = compile_id;
 588     _comp_level              = CompLevel_none;
 589     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 590     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 591     _osr_entry_point         = NULL;
 592     _exception_cache         = NULL;
 593     _pc_desc_container.reset_to(NULL);
 594     _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 595 
 596     _scopes_data_begin = (address) this + scopes_data_offset;
 597     _deopt_handler_begin = (address) this + deoptimize_offset;
 598     _deopt_mh_handler_begin = (address) this + deoptimize_mh_offset;
 599 
 600     code_buffer->copy_code_and_locs_to(this);
 601     code_buffer->copy_values_to(this);
 602     if (ScavengeRootsInCode) {
 603       Universe::heap()->register_nmethod(this);
 604     }
 605     debug_only(Universe::heap()->verify_nmethod(this));
 606     CodeCache::commit(this);
 607   }
 608 
 609   if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
 610     ttyLocker ttyl;  // keep the following output all in one block
 611     // This output goes directly to the tty, not the compiler log.
 612     // To enable tools to match it up with the compilation activity,
 613     // be sure to tag this tty output with the compile ID.
 614     if (xtty != NULL) {
 615       xtty->begin_head("print_native_nmethod");
 616       xtty->method(_method);
 617       xtty->stamp();
 618       xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
 619     }
 620     // print the header part first
 621     print();
 622     // then print the requested information
 623     if (PrintNativeNMethods) {
 624       print_code();
 625       if (oop_maps != NULL) {
 626         oop_maps->print();
 627       }
 628     }
 629     if (PrintRelocations) {
 630       print_relocations();
 631     }
 632     if (xtty != NULL) {
 633       xtty->tail("print_native_nmethod");
 634     }
 635   }
 636 }
 637 
 638 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
 639   return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
 640 }
 641 
 642 nmethod::nmethod(
 643   Method* method,
 644   CompilerType type,
 645   int nmethod_size,
 646   int compile_id,
 647   int entry_bci,
 648   CodeOffsets* offsets,
 649   int orig_pc_offset,
 650   DebugInformationRecorder* debug_info,
 651   Dependencies* dependencies,
 652   CodeBuffer *code_buffer,
 653   int frame_size,
 654   OopMapSet* oop_maps,
 655   ExceptionHandlerTable* handler_table,
 656   ImplicitExceptionTable* nul_chk_table,
 657   AbstractCompiler* compiler,
 658   int comp_level
 659 #if INCLUDE_JVMCI
 660   , jweak installed_code,
 661   jweak speculation_log
 662 #endif
 663   )
 664   : CompiledMethod(method, "nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
 665   _native_receiver_sp_offset(in_ByteSize(-1)),
 666   _native_basic_lock_sp_offset(in_ByteSize(-1))
 667 {
 668   assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
 669   {
 670     debug_only(NoSafepointVerifier nsv;)
 671     assert_locked_or_safepoint(CodeCache_lock);
 672 
 673     _deopt_handler_begin = (address) this;
 674     _deopt_mh_handler_begin = (address) this;
 675 
 676     init_defaults();
 677     _entry_bci               = entry_bci;
 678     _compile_id              = compile_id;
 679     _comp_level              = comp_level;
 680     _orig_pc_offset          = orig_pc_offset;
 681     _hotness_counter         = NMethodSweeper::hotness_counter_reset_val();
 682 
 683     // Section offsets
 684     _consts_offset           = content_offset()      + code_buffer->total_offset_of(code_buffer->consts());
 685     _stub_offset             = content_offset()      + code_buffer->total_offset_of(code_buffer->stubs());
 686     set_ctable_begin(header_begin() + _consts_offset);
 687 
 688 #if INCLUDE_JVMCI
 689     _jvmci_installed_code = installed_code;
 690     _speculation_log = speculation_log;
 691     oop obj = JNIHandles::resolve(installed_code);
 692     if (obj == NULL || (obj->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(obj))) {
 693       _jvmci_installed_code_triggers_invalidation = false;
 694     } else {
 695       _jvmci_installed_code_triggers_invalidation = true;
 696     }
 697 
 698     if (compiler->is_jvmci()) {
 699       // JVMCI might not produce any stub sections
 700       if (offsets->value(CodeOffsets::Exceptions) != -1) {
 701         _exception_offset        = code_offset()          + offsets->value(CodeOffsets::Exceptions);
 702       } else {
 703         _exception_offset = -1;
 704       }
 705       if (offsets->value(CodeOffsets::Deopt) != -1) {
 706         _deopt_handler_begin       = (address) this + code_offset()          + offsets->value(CodeOffsets::Deopt);
 707       } else {
 708         _deopt_handler_begin = NULL;
 709       }
 710       if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 711         _deopt_mh_handler_begin  = (address) this + code_offset()          + offsets->value(CodeOffsets::DeoptMH);
 712       } else {
 713         _deopt_mh_handler_begin = NULL;
 714       }
 715     } else {
 716 #endif
 717     // Exception handler and deopt handler are in the stub section
 718     assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
 719     assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
 720 
 721     _exception_offset       = _stub_offset          + offsets->value(CodeOffsets::Exceptions);
 722     _deopt_handler_begin    = (address) this + _stub_offset          + offsets->value(CodeOffsets::Deopt);
 723     if (offsets->value(CodeOffsets::DeoptMH) != -1) {
 724       _deopt_mh_handler_begin  = (address) this + _stub_offset          + offsets->value(CodeOffsets::DeoptMH);
 725     } else {
 726       _deopt_mh_handler_begin  = NULL;
 727 #if INCLUDE_JVMCI
 728     }
 729 #endif
 730     }
 731     if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
 732       _unwind_handler_offset = code_offset()         + offsets->value(CodeOffsets::UnwindHandler);
 733     } else {
 734       _unwind_handler_offset = -1;
 735     }
 736 
 737     _oops_offset             = data_offset();
 738     _metadata_offset         = _oops_offset          + align_up(code_buffer->total_oop_size(), oopSize);
 739     int scopes_data_offset   = _metadata_offset      + align_up(code_buffer->total_metadata_size(), wordSize);
 740 
 741     _scopes_pcs_offset       = scopes_data_offset    + align_up(debug_info->data_size       (), oopSize);
 742     _dependencies_offset     = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
 743     _handler_table_offset    = _dependencies_offset  + align_up((int)dependencies->size_in_bytes (), oopSize);
 744     _nul_chk_table_offset    = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
 745     _nmethod_end_offset      = _nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize);
 746     _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
 747     _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
 748     _osr_entry_point         = code_begin()          + offsets->value(CodeOffsets::OSR_Entry);
 749     _exception_cache         = NULL;
 750 
 751     _scopes_data_begin = (address) this + scopes_data_offset;
 752 
 753     _pc_desc_container.reset_to(scopes_pcs_begin());
 754 
 755     code_buffer->copy_code_and_locs_to(this);
 756     // Copy contents of ScopeDescRecorder to nmethod
 757     code_buffer->copy_values_to(this);
 758     debug_info->copy_to(this);
 759     dependencies->copy_to(this);
 760     if (ScavengeRootsInCode) {
 761       Universe::heap()->register_nmethod(this);
 762     }
 763     debug_only(Universe::heap()->verify_nmethod(this));
 764 
 765     CodeCache::commit(this);
 766 
 767     // Copy contents of ExceptionHandlerTable to nmethod
 768     handler_table->copy_to(this);
 769     nul_chk_table->copy_to(this);
 770 
 771     // we use the information of entry points to find out if a method is
 772     // static or non static
 773     assert(compiler->is_c2() || compiler->is_jvmci() ||
 774            _method->is_static() == (entry_point() == _verified_entry_point),
 775            " entry points must be same for static methods and vice versa");
 776   }
 777 }
 778 
 779 // Print a short set of xml attributes to identify this nmethod.  The
 780 // output should be embedded in some other element.
 781 void nmethod::log_identity(xmlStream* log) const {
 782   log->print(" compile_id='%d'", compile_id());
 783   const char* nm_kind = compile_kind();
 784   if (nm_kind != NULL)  log->print(" compile_kind='%s'", nm_kind);
 785   log->print(" compiler='%s'", compiler_name());
 786   if (TieredCompilation) {
 787     log->print(" level='%d'", comp_level());
 788   }
 789 #if INCLUDE_JVMCI
 790     char buffer[O_BUFLEN];
 791     char* jvmci_name = jvmci_installed_code_name(buffer, O_BUFLEN);
 792     if (jvmci_name != NULL) {
 793       log->print(" jvmci_installed_code_name='");
 794       log->text("%s", jvmci_name);
 795       log->print("'");
 796     }
 797 #endif
 798 }
 799 
 800 
 801 #define LOG_OFFSET(log, name)                    \
 802   if (p2i(name##_end()) - p2i(name##_begin())) \
 803     log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'"    , \
 804                p2i(name##_begin()) - p2i(this))
 805 
 806 
 807 void nmethod::log_new_nmethod() const {
 808   if (LogCompilation && xtty != NULL) {
 809     ttyLocker ttyl;
 810     HandleMark hm;
 811     xtty->begin_elem("nmethod");
 812     log_identity(xtty);
 813     xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
 814     xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
 815 
 816     LOG_OFFSET(xtty, relocation);
 817     LOG_OFFSET(xtty, consts);
 818     LOG_OFFSET(xtty, insts);
 819     LOG_OFFSET(xtty, stub);
 820     LOG_OFFSET(xtty, scopes_data);
 821     LOG_OFFSET(xtty, scopes_pcs);
 822     LOG_OFFSET(xtty, dependencies);
 823     LOG_OFFSET(xtty, handler_table);
 824     LOG_OFFSET(xtty, nul_chk_table);
 825     LOG_OFFSET(xtty, oops);
 826     LOG_OFFSET(xtty, metadata);
 827 
 828     xtty->method(method());
 829     xtty->stamp();
 830     xtty->end_elem();
 831   }
 832 }
 833 
 834 #undef LOG_OFFSET
 835 
 836 
 837 // Print out more verbose output usually for a newly created nmethod.
 838 void nmethod::print_on(outputStream* st, const char* msg) const {
 839   if (st != NULL) {
 840     ttyLocker ttyl;
 841     if (WizardMode) {
 842       CompileTask::print(st, this, msg, /*short_form:*/ true);
 843       st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
 844     } else {
 845       CompileTask::print(st, this, msg, /*short_form:*/ false);
 846     }
 847   }
 848 }
 849 
 850 void nmethod::maybe_print_nmethod(DirectiveSet* directive) {
 851   bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
 852   if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
 853     print_nmethod(printnmethods);
 854   }
 855 }
 856 
 857 void nmethod::print_nmethod(bool printmethod) {
 858   ttyLocker ttyl;  // keep the following output all in one block
 859   if (xtty != NULL) {
 860     xtty->begin_head("print_nmethod");
 861     xtty->stamp();
 862     xtty->end_head();
 863   }
 864   // print the header part first
 865   print();
 866   // then print the requested information
 867   if (printmethod) {
 868     print_code();
 869     print_pcs();
 870     if (oop_maps()) {
 871       oop_maps()->print();
 872     }
 873   }
 874   if (printmethod || PrintDebugInfo || CompilerOracle::has_option_string(_method, "PrintDebugInfo")) {
 875     print_scopes();
 876   }
 877   if (printmethod || PrintRelocations || CompilerOracle::has_option_string(_method, "PrintRelocations")) {
 878     print_relocations();
 879   }
 880   if (printmethod || PrintDependencies || CompilerOracle::has_option_string(_method, "PrintDependencies")) {
 881     print_dependencies();
 882   }
 883   if (printmethod || PrintExceptionHandlers) {
 884     print_handler_table();
 885     print_nul_chk_table();
 886   }
 887   if (printmethod) {
 888     print_recorded_oops();
 889     print_recorded_metadata();
 890   }
 891   if (xtty != NULL) {
 892     xtty->tail("print_nmethod");
 893   }
 894 }
 895 
 896 
 897 // Promote one word from an assembly-time handle to a live embedded oop.
 898 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
 899   if (handle == NULL ||
 900       // As a special case, IC oops are initialized to 1 or -1.
 901       handle == (jobject) Universe::non_oop_word()) {
 902     (*dest) = (oop) handle;
 903   } else {
 904     (*dest) = JNIHandles::resolve_non_null(handle);
 905   }
 906 }
 907 
 908 
 909 // Have to have the same name because it's called by a template
 910 void nmethod::copy_values(GrowableArray<jobject>* array) {
 911   int length = array->length();
 912   assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
 913   oop* dest = oops_begin();
 914   for (int index = 0 ; index < length; index++) {
 915     initialize_immediate_oop(&dest[index], array->at(index));
 916   }
 917 
 918   // Now we can fix up all the oops in the code.  We need to do this
 919   // in the code because the assembler uses jobjects as placeholders.
 920   // The code and relocations have already been initialized by the
 921   // CodeBlob constructor, so it is valid even at this early point to
 922   // iterate over relocations and patch the code.
 923   fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
 924 }
 925 
 926 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
 927   int length = array->length();
 928   assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
 929   Metadata** dest = metadata_begin();
 930   for (int index = 0 ; index < length; index++) {
 931     dest[index] = array->at(index);
 932   }
 933 }
 934 
 935 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
 936   // re-patch all oop-bearing instructions, just in case some oops moved
 937   RelocIterator iter(this, begin, end);
 938   while (iter.next()) {
 939     if (iter.type() == relocInfo::oop_type) {
 940       oop_Relocation* reloc = iter.oop_reloc();
 941       if (initialize_immediates && reloc->oop_is_immediate()) {
 942         oop* dest = reloc->oop_addr();
 943         initialize_immediate_oop(dest, (jobject) *dest);
 944       }
 945       // Refresh the oop-related bits of this instruction.
 946       reloc->fix_oop_relocation();
 947     } else if (iter.type() == relocInfo::metadata_type) {
 948       metadata_Relocation* reloc = iter.metadata_reloc();
 949       reloc->fix_metadata_relocation();
 950     }
 951   }
 952 }
 953 
 954 
 955 void nmethod::verify_clean_inline_caches() {
 956   assert_locked_or_safepoint(CompiledIC_lock);
 957 
 958   ResourceMark rm;
 959   RelocIterator iter(this, oops_reloc_begin());
 960   while(iter.next()) {
 961     switch(iter.type()) {
 962       case relocInfo::virtual_call_type:
 963       case relocInfo::opt_virtual_call_type: {
 964         CompiledIC *ic = CompiledIC_at(&iter);
 965         // Ok, to lookup references to zombies here
 966         CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
 967         assert(cb != NULL, "destination not in CodeBlob?");
 968         nmethod* nm = cb->as_nmethod_or_null();
 969         if( nm != NULL ) {
 970           // Verify that inline caches pointing to both zombie and not_entrant methods are clean
 971           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
 972             assert(ic->is_clean(), "IC should be clean");
 973           }
 974         }
 975         break;
 976       }
 977       case relocInfo::static_call_type: {
 978         CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
 979         CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
 980         assert(cb != NULL, "destination not in CodeBlob?");
 981         nmethod* nm = cb->as_nmethod_or_null();
 982         if( nm != NULL ) {
 983           // Verify that inline caches pointing to both zombie and not_entrant methods are clean
 984           if (!nm->is_in_use() || (nm->method()->code() != nm)) {
 985             assert(csc->is_clean(), "IC should be clean");
 986           }
 987         }
 988         break;
 989       }
 990       default:
 991         break;
 992     }
 993   }
 994 }
 995 
 996 // This is a private interface with the sweeper.
 997 void nmethod::mark_as_seen_on_stack() {
 998   assert(is_alive(), "Must be an alive method");
 999   // Set the traversal mark to ensure that the sweeper does 2
1000   // cleaning passes before moving to zombie.
1001   set_stack_traversal_mark(NMethodSweeper::traversal_count());
1002 }
1003 
1004 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1005 // there are no activations on the stack, not in use by the VM,
1006 // and not in use by the ServiceThread)
1007 bool nmethod::can_convert_to_zombie() {
1008   assert(is_not_entrant(), "must be a non-entrant method");
1009 
1010   // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1011   // count can be greater than the stack traversal count before it hits the
1012   // nmethod for the second time.
1013   return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1014          !is_locked_by_vm();
1015 }
1016 
1017 void nmethod::inc_decompile_count() {
1018   if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1019   // Could be gated by ProfileTraps, but do not bother...
1020   Method* m = method();
1021   if (m == NULL)  return;
1022   MethodData* mdo = m->method_data();
1023   if (mdo == NULL)  return;
1024   // There is a benign race here.  See comments in methodData.hpp.
1025   mdo->inc_decompile_count();
1026 }
1027 
1028 void nmethod::make_unloaded(oop cause) {
1029 
1030   post_compiled_method_unload();
1031 
1032   // This nmethod is being unloaded, make sure that dependencies
1033   // recorded in instanceKlasses get flushed.
1034   // Since this work is being done during a GC, defer deleting dependencies from the
1035   // InstanceKlass.
1036   assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1037   flush_dependencies(/*delete_immediately*/false);
1038 
1039   // Break cycle between nmethod & method
1040   LogTarget(Trace, class, unload, nmethod) lt;
1041   if (lt.is_enabled()) {
1042     LogStream ls(lt);
1043     ls.print("making nmethod " INTPTR_FORMAT
1044              " unloadable, Method*(" INTPTR_FORMAT
1045              "), cause(" INTPTR_FORMAT ") ",
1046              p2i(this), p2i(_method), p2i(cause));
1047      if (cause != NULL) {
1048        cause->print_value_on(&ls);
1049      }
1050      ls.cr();
1051   }
1052   // Unlink the osr method, so we do not look this up again
1053   if (is_osr_method()) {
1054     // Invalidate the osr nmethod only once
1055     if (is_in_use()) {
1056       invalidate_osr_method();
1057     }
1058 #ifdef ASSERT
1059     if (method() != NULL) {
1060       // Make sure osr nmethod is invalidated, i.e. not on the list
1061       bool found = method()->method_holder()->remove_osr_nmethod(this);
1062       assert(!found, "osr nmethod should have been invalidated");
1063     }
1064 #endif
1065   }
1066 
1067   // If _method is already NULL the Method* is about to be unloaded,
1068   // so we don't have to break the cycle. Note that it is possible to
1069   // have the Method* live here, in case we unload the nmethod because
1070   // it is pointing to some oop (other than the Method*) being unloaded.
1071   if (_method != NULL) {
1072     // OSR methods point to the Method*, but the Method* does not
1073     // point back!
1074     if (_method->code() == this) {
1075       _method->clear_code(); // Break a cycle
1076     }
1077     _method = NULL;            // Clear the method of this dead nmethod
1078   }
1079 
1080   // Make the class unloaded - i.e., change state and notify sweeper
1081   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1082   if (is_in_use()) {
1083     // Transitioning directly from live to unloaded -- so
1084     // we need to force a cache clean-up; remember this
1085     // for later on.
1086     CodeCache::set_needs_cache_clean(true);
1087   }
1088 
1089   // Unregister must be done before the state change
1090   Universe::heap()->unregister_nmethod(this);
1091 
1092   _state = unloaded;
1093 
1094   // Log the unloading.
1095   log_state_change(cause);
1096 
1097 #if INCLUDE_JVMCI
1098   // The method can only be unloaded after the pointer to the installed code
1099   // Java wrapper is no longer alive. Here we need to clear out this weak
1100   // reference to the dead object.
1101   maybe_invalidate_installed_code();
1102 #endif
1103 
1104   // The Method* is gone at this point
1105   assert(_method == NULL, "Tautology");
1106 
1107   set_osr_link(NULL);
1108   NMethodSweeper::report_state_change(this);
1109 }
1110 
1111 void nmethod::invalidate_osr_method() {
1112   assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1113   // Remove from list of active nmethods
1114   if (method() != NULL) {
1115     method()->method_holder()->remove_osr_nmethod(this);
1116   }
1117 }
1118 
1119 void nmethod::log_state_change(oop cause) const {
1120   if (LogCompilation) {
1121     if (xtty != NULL) {
1122       ttyLocker ttyl;  // keep the following output all in one block
1123       if (_state == unloaded) {
1124         xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1125                          os::current_thread_id());
1126       } else {
1127         xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1128                          os::current_thread_id(),
1129                          (_state == zombie ? " zombie='1'" : ""));
1130       }
1131       log_identity(xtty);
1132       if (cause != NULL) {
1133         xtty->print(" cause='%s'", cause->klass()->external_name());
1134       }
1135       xtty->stamp();
1136       xtty->end_elem();
1137     }
1138   }
1139 
1140   const char *state_msg = _state == zombie ? "made zombie" : "made not entrant";
1141   CompileTask::print_ul(this, state_msg);
1142   if (PrintCompilation && _state != unloaded) {
1143     print_on(tty, state_msg);
1144   }
1145 }
1146 
1147 /**
1148  * Common functionality for both make_not_entrant and make_zombie
1149  */
1150 bool nmethod::make_not_entrant_or_zombie(int state) {
1151   assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1152   assert(!is_zombie(), "should not already be a zombie");
1153 
1154   if (_state == state) {
1155     // Avoid taking the lock if already in required state.
1156     // This is safe from races because the state is an end-state,
1157     // which the nmethod cannot back out of once entered.
1158     // No need for fencing either.
1159     return false;
1160   }
1161 
1162   // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1163   nmethodLocker nml(this);
1164   methodHandle the_method(method());
1165   // This can be called while the system is already at a safepoint which is ok
1166   NoSafepointVerifier nsv(true, !SafepointSynchronize::is_at_safepoint());
1167 
1168   // during patching, depending on the nmethod state we must notify the GC that
1169   // code has been unloaded, unregistering it. We cannot do this right while
1170   // holding the Patching_lock because we need to use the CodeCache_lock. This
1171   // would be prone to deadlocks.
1172   // This flag is used to remember whether we need to later lock and unregister.
1173   bool nmethod_needs_unregister = false;
1174 
1175   {
1176     // invalidate osr nmethod before acquiring the patching lock since
1177     // they both acquire leaf locks and we don't want a deadlock.
1178     // This logic is equivalent to the logic below for patching the
1179     // verified entry point of regular methods. We check that the
1180     // nmethod is in use to ensure that it is invalidated only once.
1181     if (is_osr_method() && is_in_use()) {
1182       // this effectively makes the osr nmethod not entrant
1183       invalidate_osr_method();
1184     }
1185 
1186     // Enter critical section.  Does not block for safepoint.
1187     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1188 
1189     if (_state == state) {
1190       // another thread already performed this transition so nothing
1191       // to do, but return false to indicate this.
1192       return false;
1193     }
1194 
1195     // The caller can be calling the method statically or through an inline
1196     // cache call.
1197     if (!is_osr_method() && !is_not_entrant()) {
1198       NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1199                   SharedRuntime::get_handle_wrong_method_stub());
1200     }
1201 
1202     if (is_in_use() && update_recompile_counts()) {
1203       // It's a true state change, so mark the method as decompiled.
1204       // Do it only for transition from alive.
1205       inc_decompile_count();
1206     }
1207 
1208     // If the state is becoming a zombie, signal to unregister the nmethod with
1209     // the heap.
1210     // This nmethod may have already been unloaded during a full GC.
1211     if ((state == zombie) && !is_unloaded()) {
1212       nmethod_needs_unregister = true;
1213     }
1214 
1215     // Must happen before state change. Otherwise we have a race condition in
1216     // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1217     // transition its state from 'not_entrant' to 'zombie' without having to wait
1218     // for stack scanning.
1219     if (state == not_entrant) {
1220       mark_as_seen_on_stack();
1221       OrderAccess::storestore(); // _stack_traversal_mark and _state
1222     }
1223 
1224     // Change state
1225     _state = state;
1226 
1227     // Log the transition once
1228     log_state_change();
1229 
1230     // Invalidate while holding the patching lock
1231     JVMCI_ONLY(maybe_invalidate_installed_code());
1232 
1233     // Remove nmethod from method.
1234     // We need to check if both the _code and _from_compiled_code_entry_point
1235     // refer to this nmethod because there is a race in setting these two fields
1236     // in Method* as seen in bugid 4947125.
1237     // If the vep() points to the zombie nmethod, the memory for the nmethod
1238     // could be flushed and the compiler and vtable stubs could still call
1239     // through it.
1240     if (method() != NULL && (method()->code() == this ||
1241                              method()->from_compiled_entry() == verified_entry_point())) {
1242       HandleMark hm;
1243       method()->clear_code(false /* already owns Patching_lock */);
1244     }
1245   } // leave critical region under Patching_lock
1246 
1247 #ifdef ASSERT
1248   if (is_osr_method() && method() != NULL) {
1249     // Make sure osr nmethod is invalidated, i.e. not on the list
1250     bool found = method()->method_holder()->remove_osr_nmethod(this);
1251     assert(!found, "osr nmethod should have been invalidated");
1252   }
1253 #endif
1254 
1255   // When the nmethod becomes zombie it is no longer alive so the
1256   // dependencies must be flushed.  nmethods in the not_entrant
1257   // state will be flushed later when the transition to zombie
1258   // happens or they get unloaded.
1259   if (state == zombie) {
1260     {
1261       // Flushing dependencies must be done before any possible
1262       // safepoint can sneak in, otherwise the oops used by the
1263       // dependency logic could have become stale.
1264       MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1265       if (nmethod_needs_unregister) {
1266         Universe::heap()->unregister_nmethod(this);
1267       }
1268       flush_dependencies(/*delete_immediately*/true);
1269     }
1270 
1271     // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1272     // event and it hasn't already been reported for this nmethod then
1273     // report it now. The event may have been reported earlier if the GC
1274     // marked it for unloading). JvmtiDeferredEventQueue support means
1275     // we no longer go to a safepoint here.
1276     post_compiled_method_unload();
1277 
1278 #ifdef ASSERT
1279     // It's no longer safe to access the oops section since zombie
1280     // nmethods aren't scanned for GC.
1281     _oops_are_stale = true;
1282 #endif
1283      // the Method may be reclaimed by class unloading now that the
1284      // nmethod is in zombie state
1285     set_method(NULL);
1286   } else {
1287     assert(state == not_entrant, "other cases may need to be handled differently");
1288   }
1289 
1290   if (TraceCreateZombies) {
1291     ResourceMark m;
1292     tty->print_cr("nmethod <" INTPTR_FORMAT "> %s code made %s", p2i(this), this->method() ? this->method()->name_and_sig_as_C_string() : "null", (state == not_entrant) ? "not entrant" : "zombie");
1293   }
1294 
1295   NMethodSweeper::report_state_change(this);
1296   return true;
1297 }
1298 
1299 void nmethod::flush() {
1300   // Note that there are no valid oops in the nmethod anymore.
1301   assert(!is_osr_method() || is_unloaded() || is_zombie(),
1302          "osr nmethod must be unloaded or zombie before flushing");
1303   assert(is_zombie() || is_osr_method(), "must be a zombie method");
1304   assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1305   assert_locked_or_safepoint(CodeCache_lock);
1306 
1307   // completely deallocate this method
1308   Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, p2i(this));
1309   if (PrintMethodFlushing) {
1310     tty->print_cr("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
1311                   "/Free CodeCache:" SIZE_FORMAT "Kb",
1312                   is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
1313                   CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
1314   }
1315 
1316   // We need to deallocate any ExceptionCache data.
1317   // Note that we do not need to grab the nmethod lock for this, it
1318   // better be thread safe if we're disposing of it!
1319   ExceptionCache* ec = exception_cache();
1320   set_exception_cache(NULL);
1321   while(ec != NULL) {
1322     ExceptionCache* next = ec->next();
1323     delete ec;
1324     ec = next;
1325   }
1326 
1327   if (on_scavenge_root_list()) {
1328     CodeCache::drop_scavenge_root_nmethod(this);
1329   }
1330 
1331 #if INCLUDE_JVMCI
1332   assert(_jvmci_installed_code == NULL, "should have been nulled out when transitioned to zombie");
1333   assert(_speculation_log == NULL, "should have been nulled out when transitioned to zombie");
1334 #endif
1335 
1336   CodeBlob::flush();
1337   CodeCache::free(this);
1338 }
1339 
1340 //
1341 // Notify all classes this nmethod is dependent on that it is no
1342 // longer dependent. This should only be called in two situations.
1343 // First, when a nmethod transitions to a zombie all dependents need
1344 // to be clear.  Since zombification happens at a safepoint there's no
1345 // synchronization issues.  The second place is a little more tricky.
1346 // During phase 1 of mark sweep class unloading may happen and as a
1347 // result some nmethods may get unloaded.  In this case the flushing
1348 // of dependencies must happen during phase 1 since after GC any
1349 // dependencies in the unloaded nmethod won't be updated, so
1350 // traversing the dependency information in unsafe.  In that case this
1351 // function is called with a boolean argument and this function only
1352 // notifies instanceKlasses that are reachable
1353 
1354 void nmethod::flush_dependencies(bool delete_immediately) {
1355   assert_locked_or_safepoint(CodeCache_lock);
1356   assert(Universe::heap()->is_gc_active() != delete_immediately,
1357   "delete_immediately is false if and only if we are called during GC");
1358   if (!has_flushed_dependencies()) {
1359     set_has_flushed_dependencies();
1360     for (Dependencies::DepStream deps(this); deps.next(); ) {
1361       if (deps.type() == Dependencies::call_site_target_value) {
1362         // CallSite dependencies are managed on per-CallSite instance basis.
1363         oop call_site = deps.argument_oop(0);
1364         MethodHandles::remove_dependent_nmethod(call_site, this);
1365       } else {
1366         Klass* klass = deps.context_type();
1367         if (klass == NULL) {
1368           continue;  // ignore things like evol_method
1369         }
1370         // During GC delete_immediately is false, and liveness
1371         // of dependee determines class that needs to be updated.
1372         if (delete_immediately || klass->is_loader_alive()) {
1373           // The GC defers deletion of this entry, since there might be multiple threads
1374           // iterating over the _dependencies graph. Other call paths are single-threaded
1375           // and may delete it immediately.
1376           InstanceKlass::cast(klass)->remove_dependent_nmethod(this, delete_immediately);
1377         }
1378       }
1379     }
1380   }
1381 }
1382 
1383 
1384 // If this oop is not live, the nmethod can be unloaded.
1385 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root) {
1386   assert(root != NULL, "just checking");
1387   oop obj = *root;
1388   if (obj == NULL || is_alive->do_object_b(obj)) {
1389       return false;
1390   }
1391 
1392   // An nmethod might be unloaded simply because one of its constant oops has gone dead.
1393   // No actual classes need to be unloaded in order for this to occur.
1394   make_unloaded(obj);
1395   return true;
1396 }
1397 
1398 // ------------------------------------------------------------------
1399 // post_compiled_method_load_event
1400 // new method for install_code() path
1401 // Transfer information from compilation to jvmti
1402 void nmethod::post_compiled_method_load_event() {
1403 
1404   Method* moop = method();
1405   HOTSPOT_COMPILED_METHOD_LOAD(
1406       (char *) moop->klass_name()->bytes(),
1407       moop->klass_name()->utf8_length(),
1408       (char *) moop->name()->bytes(),
1409       moop->name()->utf8_length(),
1410       (char *) moop->signature()->bytes(),
1411       moop->signature()->utf8_length(),
1412       insts_begin(), insts_size());
1413 
1414   if (JvmtiExport::should_post_compiled_method_load() ||
1415       JvmtiExport::should_post_compiled_method_unload()) {
1416     get_and_cache_jmethod_id();
1417   }
1418 
1419   if (JvmtiExport::should_post_compiled_method_load()) {
1420     // Let the Service thread (which is a real Java thread) post the event
1421     MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1422     JvmtiDeferredEventQueue::enqueue(
1423       JvmtiDeferredEvent::compiled_method_load_event(this));
1424   }
1425 }
1426 
1427 jmethodID nmethod::get_and_cache_jmethod_id() {
1428   if (_jmethod_id == NULL) {
1429     // Cache the jmethod_id since it can no longer be looked up once the
1430     // method itself has been marked for unloading.
1431     _jmethod_id = method()->jmethod_id();
1432   }
1433   return _jmethod_id;
1434 }
1435 
1436 void nmethod::post_compiled_method_unload() {
1437   if (unload_reported()) {
1438     // During unloading we transition to unloaded and then to zombie
1439     // and the unloading is reported during the first transition.
1440     return;
1441   }
1442 
1443   assert(_method != NULL && !is_unloaded(), "just checking");
1444   DTRACE_METHOD_UNLOAD_PROBE(method());
1445 
1446   // If a JVMTI agent has enabled the CompiledMethodUnload event then
1447   // post the event. Sometime later this nmethod will be made a zombie
1448   // by the sweeper but the Method* will not be valid at that point.
1449   // If the _jmethod_id is null then no load event was ever requested
1450   // so don't bother posting the unload.  The main reason for this is
1451   // that the jmethodID is a weak reference to the Method* so if
1452   // it's being unloaded there's no way to look it up since the weak
1453   // ref will have been cleared.
1454   if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1455     assert(!unload_reported(), "already unloaded");
1456     JvmtiDeferredEvent event =
1457       JvmtiDeferredEvent::compiled_method_unload_event(this,
1458           _jmethod_id, insts_begin());
1459     MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1460     JvmtiDeferredEventQueue::enqueue(event);
1461   }
1462 
1463   // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1464   // any time. As the nmethod is being unloaded now we mark it has
1465   // having the unload event reported - this will ensure that we don't
1466   // attempt to report the event in the unlikely scenario where the
1467   // event is enabled at the time the nmethod is made a zombie.
1468   set_unload_reported();
1469 }
1470 
1471 bool nmethod::unload_if_dead_at(RelocIterator* iter_at_oop, BoolObjectClosure *is_alive) {
1472   assert(iter_at_oop->type() == relocInfo::oop_type, "Wrong relocation type");
1473 
1474   oop_Relocation* r = iter_at_oop->oop_reloc();
1475   // Traverse those oops directly embedded in the code.
1476   // Other oops (oop_index>0) are seen as part of scopes_oops.
1477   assert(1 == (r->oop_is_immediate()) +
1478          (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1479          "oop must be found in exactly one place");
1480   if (r->oop_is_immediate() && r->oop_value() != NULL) {
1481     // Unload this nmethod if the oop is dead.
1482     if (can_unload(is_alive, r->oop_addr())) {
1483       return true;;
1484     }
1485   }
1486 
1487   return false;
1488 }
1489 
1490 bool nmethod::do_unloading_scopes(BoolObjectClosure* is_alive) {
1491   // Scopes
1492   for (oop* p = oops_begin(); p < oops_end(); p++) {
1493     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1494     if (can_unload(is_alive, p)) {
1495       return true;
1496     }
1497   }
1498   return false;
1499 }
1500 
1501 bool nmethod::do_unloading_oops(address low_boundary, BoolObjectClosure* is_alive) {
1502   // Compiled code
1503 
1504   // Prevent extra code cache walk for platforms that don't have immediate oops.
1505   if (relocInfo::mustIterateImmediateOopsInCode()) {
1506     RelocIterator iter(this, low_boundary);
1507     while (iter.next()) {
1508       if (iter.type() == relocInfo::oop_type) {
1509         if (unload_if_dead_at(&iter, is_alive)) {
1510           return true;
1511         }
1512       }
1513     }
1514   }
1515 
1516   return do_unloading_scopes(is_alive);
1517 }
1518 
1519 #if INCLUDE_JVMCI
1520 bool nmethod::do_unloading_jvmci() {
1521   if (_jvmci_installed_code != NULL) {
1522     if (JNIHandles::is_global_weak_cleared(_jvmci_installed_code)) {
1523       if (_jvmci_installed_code_triggers_invalidation) {
1524         // The reference to the installed code has been dropped so invalidate
1525         // this nmethod and allow the sweeper to reclaim it.
1526         make_not_entrant();
1527       }
1528       clear_jvmci_installed_code();
1529     }
1530   }
1531   return false;
1532 }
1533 #endif
1534 
1535 // Iterate over metadata calling this function.   Used by RedefineClasses
1536 void nmethod::metadata_do(void f(Metadata*)) {
1537   {
1538     // Visit all immediate references that are embedded in the instruction stream.
1539     RelocIterator iter(this, oops_reloc_begin());
1540     while (iter.next()) {
1541       if (iter.type() == relocInfo::metadata_type ) {
1542         metadata_Relocation* r = iter.metadata_reloc();
1543         // In this metadata, we must only follow those metadatas directly embedded in
1544         // the code.  Other metadatas (oop_index>0) are seen as part of
1545         // the metadata section below.
1546         assert(1 == (r->metadata_is_immediate()) +
1547                (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1548                "metadata must be found in exactly one place");
1549         if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1550           Metadata* md = r->metadata_value();
1551           if (md != _method) f(md);
1552         }
1553       } else if (iter.type() == relocInfo::virtual_call_type) {
1554         // Check compiledIC holders associated with this nmethod
1555         ResourceMark rm;
1556         CompiledIC *ic = CompiledIC_at(&iter);
1557         if (ic->is_icholder_call()) {
1558           CompiledICHolder* cichk = ic->cached_icholder();
1559           f(cichk->holder_metadata());
1560           f(cichk->holder_klass());
1561         } else {
1562           Metadata* ic_oop = ic->cached_metadata();
1563           if (ic_oop != NULL) {
1564             f(ic_oop);
1565           }
1566         }
1567       }
1568     }
1569   }
1570 
1571   // Visit the metadata section
1572   for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1573     if (*p == Universe::non_oop_word() || *p == NULL)  continue;  // skip non-oops
1574     Metadata* md = *p;
1575     f(md);
1576   }
1577 
1578   // Visit metadata not embedded in the other places.
1579   if (_method != NULL) f(_method);
1580 }
1581 
1582 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1583   // make sure the oops ready to receive visitors
1584   assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1585   assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1586 
1587   // Prevent extra code cache walk for platforms that don't have immediate oops.
1588   if (relocInfo::mustIterateImmediateOopsInCode()) {
1589     RelocIterator iter(this, oops_reloc_begin());
1590 
1591     while (iter.next()) {
1592       if (iter.type() == relocInfo::oop_type ) {
1593         oop_Relocation* r = iter.oop_reloc();
1594         // In this loop, we must only follow those oops directly embedded in
1595         // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
1596         assert(1 == (r->oop_is_immediate()) +
1597                (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1598                "oop must be found in exactly one place");
1599         if (r->oop_is_immediate() && r->oop_value() != NULL) {
1600           f->do_oop(r->oop_addr());
1601         }
1602       }
1603     }
1604   }
1605 
1606   // Scopes
1607   // This includes oop constants not inlined in the code stream.
1608   for (oop* p = oops_begin(); p < oops_end(); p++) {
1609     if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1610     f->do_oop(p);
1611   }
1612 }
1613 
1614 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1615 
1616 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1617 
1618 // An nmethod is "marked" if its _mark_link is set non-null.
1619 // Even if it is the end of the linked list, it will have a non-null link value,
1620 // as long as it is on the list.
1621 // This code must be MP safe, because it is used from parallel GC passes.
1622 bool nmethod::test_set_oops_do_mark() {
1623   assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1624   if (_oops_do_mark_link == NULL) {
1625     // Claim this nmethod for this thread to mark.
1626     if (Atomic::replace_if_null(NMETHOD_SENTINEL, &_oops_do_mark_link)) {
1627       // Atomically append this nmethod (now claimed) to the head of the list:
1628       nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1629       for (;;) {
1630         nmethod* required_mark_nmethods = observed_mark_nmethods;
1631         _oops_do_mark_link = required_mark_nmethods;
1632         observed_mark_nmethods =
1633           Atomic::cmpxchg(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1634         if (observed_mark_nmethods == required_mark_nmethods)
1635           break;
1636       }
1637       // Mark was clear when we first saw this guy.
1638       LogTarget(Trace, gc, nmethod) lt;
1639       if (lt.is_enabled()) {
1640         LogStream ls(lt);
1641         CompileTask::print(&ls, this, "oops_do, mark", /*short_form:*/ true);
1642       }
1643       return false;
1644     }
1645   }
1646   // On fall through, another racing thread marked this nmethod before we did.
1647   return true;
1648 }
1649 
1650 void nmethod::oops_do_marking_prologue() {
1651   log_trace(gc, nmethod)("oops_do_marking_prologue");
1652   assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1653   // We use cmpxchg instead of regular assignment here because the user
1654   // may fork a bunch of threads, and we need them all to see the same state.
1655   nmethod* observed = Atomic::cmpxchg(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, (nmethod*)NULL);
1656   guarantee(observed == NULL, "no races in this sequential code");
1657 }
1658 
1659 void nmethod::oops_do_marking_epilogue() {
1660   assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1661   nmethod* cur = _oops_do_mark_nmethods;
1662   while (cur != NMETHOD_SENTINEL) {
1663     assert(cur != NULL, "not NULL-terminated");
1664     nmethod* next = cur->_oops_do_mark_link;
1665     cur->_oops_do_mark_link = NULL;
1666     DEBUG_ONLY(cur->verify_oop_relocations());
1667 
1668     LogTarget(Trace, gc, nmethod) lt;
1669     if (lt.is_enabled()) {
1670       LogStream ls(lt);
1671       CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
1672     }
1673     cur = next;
1674   }
1675   nmethod* required = _oops_do_mark_nmethods;
1676   nmethod* observed = Atomic::cmpxchg((nmethod*)NULL, &_oops_do_mark_nmethods, required);
1677   guarantee(observed == required, "no races in this sequential code");
1678   log_trace(gc, nmethod)("oops_do_marking_epilogue");
1679 }
1680 
1681 class DetectScavengeRoot: public OopClosure {
1682   bool     _detected_scavenge_root;
1683   nmethod* _print_nm;
1684 public:
1685   DetectScavengeRoot(nmethod* nm) : _detected_scavenge_root(false), _print_nm(nm) {}
1686 
1687   bool detected_scavenge_root() { return _detected_scavenge_root; }
1688   virtual void do_oop(oop* p) {
1689     if ((*p) != NULL && Universe::heap()->is_scavengable(*p)) {
1690       NOT_PRODUCT(maybe_print(p));
1691       _detected_scavenge_root = true;
1692     }
1693   }
1694   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1695 
1696 #ifndef PRODUCT
1697   void maybe_print(oop* p) {
1698     LogTarget(Trace, gc, nmethod) lt;
1699     if (lt.is_enabled()) {
1700       LogStream ls(lt);
1701       if (!_detected_scavenge_root) {
1702         CompileTask::print(&ls, _print_nm, "new scavenge root", /*short_form:*/ true);
1703       }
1704       ls.print("" PTR_FORMAT "[offset=%d] detected scavengable oop " PTR_FORMAT " (found at " PTR_FORMAT ") ",
1705                p2i(_print_nm), (int)((intptr_t)p - (intptr_t)_print_nm),
1706                p2i(*p), p2i(p));
1707       ls.cr();
1708     }
1709   }
1710 #endif //PRODUCT
1711 };
1712 
1713 bool nmethod::detect_scavenge_root_oops() {
1714   DetectScavengeRoot detect_scavenge_root(this);
1715   oops_do(&detect_scavenge_root);
1716   return detect_scavenge_root.detected_scavenge_root();
1717 }
1718 
1719 inline bool includes(void* p, void* from, void* to) {
1720   return from <= p && p < to;
1721 }
1722 
1723 
1724 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1725   assert(count >= 2, "must be sentinel values, at least");
1726 
1727 #ifdef ASSERT
1728   // must be sorted and unique; we do a binary search in find_pc_desc()
1729   int prev_offset = pcs[0].pc_offset();
1730   assert(prev_offset == PcDesc::lower_offset_limit,
1731          "must start with a sentinel");
1732   for (int i = 1; i < count; i++) {
1733     int this_offset = pcs[i].pc_offset();
1734     assert(this_offset > prev_offset, "offsets must be sorted");
1735     prev_offset = this_offset;
1736   }
1737   assert(prev_offset == PcDesc::upper_offset_limit,
1738          "must end with a sentinel");
1739 #endif //ASSERT
1740 
1741   // Search for MethodHandle invokes and tag the nmethod.
1742   for (int i = 0; i < count; i++) {
1743     if (pcs[i].is_method_handle_invoke()) {
1744       set_has_method_handle_invokes(true);
1745       break;
1746     }
1747   }
1748   assert(has_method_handle_invokes() == (_deopt_mh_handler_begin != NULL), "must have deopt mh handler");
1749 
1750   int size = count * sizeof(PcDesc);
1751   assert(scopes_pcs_size() >= size, "oob");
1752   memcpy(scopes_pcs_begin(), pcs, size);
1753 
1754   // Adjust the final sentinel downward.
1755   PcDesc* last_pc = &scopes_pcs_begin()[count-1];
1756   assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
1757   last_pc->set_pc_offset(content_size() + 1);
1758   for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
1759     // Fill any rounding gaps with copies of the last record.
1760     last_pc[1] = last_pc[0];
1761   }
1762   // The following assert could fail if sizeof(PcDesc) is not
1763   // an integral multiple of oopSize (the rounding term).
1764   // If it fails, change the logic to always allocate a multiple
1765   // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
1766   assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
1767 }
1768 
1769 void nmethod::copy_scopes_data(u_char* buffer, int size) {
1770   assert(scopes_data_size() >= size, "oob");
1771   memcpy(scopes_data_begin(), buffer, size);
1772 }
1773 
1774 #ifdef ASSERT
1775 static PcDesc* linear_search(const PcDescSearch& search, int pc_offset, bool approximate) {
1776   PcDesc* lower = search.scopes_pcs_begin();
1777   PcDesc* upper = search.scopes_pcs_end();
1778   lower += 1; // exclude initial sentinel
1779   PcDesc* res = NULL;
1780   for (PcDesc* p = lower; p < upper; p++) {
1781     NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
1782     if (match_desc(p, pc_offset, approximate)) {
1783       if (res == NULL)
1784         res = p;
1785       else
1786         res = (PcDesc*) badAddress;
1787     }
1788   }
1789   return res;
1790 }
1791 #endif
1792 
1793 
1794 // Finds a PcDesc with real-pc equal to "pc"
1795 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, const PcDescSearch& search) {
1796   address base_address = search.code_begin();
1797   if ((pc < base_address) ||
1798       (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
1799     return NULL;  // PC is wildly out of range
1800   }
1801   int pc_offset = (int) (pc - base_address);
1802 
1803   // Check the PcDesc cache if it contains the desired PcDesc
1804   // (This as an almost 100% hit rate.)
1805   PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
1806   if (res != NULL) {
1807     assert(res == linear_search(search, pc_offset, approximate), "cache ok");
1808     return res;
1809   }
1810 
1811   // Fallback algorithm: quasi-linear search for the PcDesc
1812   // Find the last pc_offset less than the given offset.
1813   // The successor must be the required match, if there is a match at all.
1814   // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
1815   PcDesc* lower = search.scopes_pcs_begin();
1816   PcDesc* upper = search.scopes_pcs_end();
1817   upper -= 1; // exclude final sentinel
1818   if (lower >= upper)  return NULL;  // native method; no PcDescs at all
1819 
1820 #define assert_LU_OK \
1821   /* invariant on lower..upper during the following search: */ \
1822   assert(lower->pc_offset() <  pc_offset, "sanity"); \
1823   assert(upper->pc_offset() >= pc_offset, "sanity")
1824   assert_LU_OK;
1825 
1826   // Use the last successful return as a split point.
1827   PcDesc* mid = _pc_desc_cache.last_pc_desc();
1828   NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1829   if (mid->pc_offset() < pc_offset) {
1830     lower = mid;
1831   } else {
1832     upper = mid;
1833   }
1834 
1835   // Take giant steps at first (4096, then 256, then 16, then 1)
1836   const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
1837   const int RADIX = (1 << LOG2_RADIX);
1838   for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
1839     while ((mid = lower + step) < upper) {
1840       assert_LU_OK;
1841       NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1842       if (mid->pc_offset() < pc_offset) {
1843         lower = mid;
1844       } else {
1845         upper = mid;
1846         break;
1847       }
1848     }
1849     assert_LU_OK;
1850   }
1851 
1852   // Sneak up on the value with a linear search of length ~16.
1853   while (true) {
1854     assert_LU_OK;
1855     mid = lower + 1;
1856     NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
1857     if (mid->pc_offset() < pc_offset) {
1858       lower = mid;
1859     } else {
1860       upper = mid;
1861       break;
1862     }
1863   }
1864 #undef assert_LU_OK
1865 
1866   if (match_desc(upper, pc_offset, approximate)) {
1867     assert(upper == linear_search(search, pc_offset, approximate), "search ok");
1868     _pc_desc_cache.add_pc_desc(upper);
1869     return upper;
1870   } else {
1871     assert(NULL == linear_search(search, pc_offset, approximate), "search ok");
1872     return NULL;
1873   }
1874 }
1875 
1876 
1877 void nmethod::check_all_dependencies(DepChange& changes) {
1878   // Checked dependencies are allocated into this ResourceMark
1879   ResourceMark rm;
1880 
1881   // Turn off dependency tracing while actually testing dependencies.
1882   NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
1883 
1884   typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
1885                             &DependencySignature::equals, 11027> DepTable;
1886 
1887   DepTable* table = new DepTable();
1888 
1889   // Iterate over live nmethods and check dependencies of all nmethods that are not
1890   // marked for deoptimization. A particular dependency is only checked once.
1891   NMethodIterator iter;
1892   while(iter.next()) {
1893     nmethod* nm = iter.method();
1894     // Only notify for live nmethods
1895     if (nm->is_alive() && !nm->is_marked_for_deoptimization()) {
1896       for (Dependencies::DepStream deps(nm); deps.next(); ) {
1897         // Construct abstraction of a dependency.
1898         DependencySignature* current_sig = new DependencySignature(deps);
1899 
1900         // Determine if dependency is already checked. table->put(...) returns
1901         // 'true' if the dependency is added (i.e., was not in the hashtable).
1902         if (table->put(*current_sig, 1)) {
1903           if (deps.check_dependency() != NULL) {
1904             // Dependency checking failed. Print out information about the failed
1905             // dependency and finally fail with an assert. We can fail here, since
1906             // dependency checking is never done in a product build.
1907             tty->print_cr("Failed dependency:");
1908             changes.print();
1909             nm->print();
1910             nm->print_dependencies();
1911             assert(false, "Should have been marked for deoptimization");
1912           }
1913         }
1914       }
1915     }
1916   }
1917 }
1918 
1919 bool nmethod::check_dependency_on(DepChange& changes) {
1920   // What has happened:
1921   // 1) a new class dependee has been added
1922   // 2) dependee and all its super classes have been marked
1923   bool found_check = false;  // set true if we are upset
1924   for (Dependencies::DepStream deps(this); deps.next(); ) {
1925     // Evaluate only relevant dependencies.
1926     if (deps.spot_check_dependency_at(changes) != NULL) {
1927       found_check = true;
1928       NOT_DEBUG(break);
1929     }
1930   }
1931   return found_check;
1932 }
1933 
1934 bool nmethod::is_evol_dependent_on(Klass* dependee) {
1935   InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
1936   Array<Method*>* dependee_methods = dependee_ik->methods();
1937   for (Dependencies::DepStream deps(this); deps.next(); ) {
1938     if (deps.type() == Dependencies::evol_method) {
1939       Method* method = deps.method_argument(0);
1940       for (int j = 0; j < dependee_methods->length(); j++) {
1941         if (dependee_methods->at(j) == method) {
1942           if (log_is_enabled(Debug, redefine, class, nmethod)) {
1943             ResourceMark rm;
1944             log_debug(redefine, class, nmethod)
1945               ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
1946                _method->method_holder()->external_name(),
1947                _method->name()->as_C_string(),
1948                _method->signature()->as_C_string(),
1949                compile_id(),
1950                method->method_holder()->external_name(),
1951                method->name()->as_C_string(),
1952                method->signature()->as_C_string());
1953           }
1954           if (TraceDependencies || LogCompilation)
1955             deps.log_dependency(dependee);
1956           return true;
1957         }
1958       }
1959     }
1960   }
1961   return false;
1962 }
1963 
1964 // Called from mark_for_deoptimization, when dependee is invalidated.
1965 bool nmethod::is_dependent_on_method(Method* dependee) {
1966   for (Dependencies::DepStream deps(this); deps.next(); ) {
1967     if (deps.type() != Dependencies::evol_method)
1968       continue;
1969     Method* method = deps.method_argument(0);
1970     if (method == dependee) return true;
1971   }
1972   return false;
1973 }
1974 
1975 
1976 bool nmethod::is_patchable_at(address instr_addr) {
1977   assert(insts_contains(instr_addr), "wrong nmethod used");
1978   if (is_zombie()) {
1979     // a zombie may never be patched
1980     return false;
1981   }
1982   return true;
1983 }
1984 
1985 
1986 address nmethod::continuation_for_implicit_exception(address pc) {
1987   // Exception happened outside inline-cache check code => we are inside
1988   // an active nmethod => use cpc to determine a return address
1989   int exception_offset = pc - code_begin();
1990   int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
1991 #ifdef ASSERT
1992   if (cont_offset == 0) {
1993     Thread* thread = Thread::current();
1994     ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
1995     HandleMark hm(thread);
1996     ResourceMark rm(thread);
1997     CodeBlob* cb = CodeCache::find_blob(pc);
1998     assert(cb != NULL && cb == this, "");
1999     ttyLocker ttyl;
2000     tty->print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
2001     print();
2002     method()->print_codes();
2003     print_code();
2004     print_pcs();
2005   }
2006 #endif
2007   if (cont_offset == 0) {
2008     // Let the normal error handling report the exception
2009     return NULL;
2010   }
2011   return code_begin() + cont_offset;
2012 }
2013 
2014 
2015 
2016 void nmethod_init() {
2017   // make sure you didn't forget to adjust the filler fields
2018   assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2019 }
2020 
2021 
2022 //-------------------------------------------------------------------------------------------
2023 
2024 
2025 // QQQ might we make this work from a frame??
2026 nmethodLocker::nmethodLocker(address pc) {
2027   CodeBlob* cb = CodeCache::find_blob(pc);
2028   guarantee(cb != NULL && cb->is_compiled(), "bad pc for a nmethod found");
2029   _nm = cb->as_compiled_method();
2030   lock_nmethod(_nm);
2031 }
2032 
2033 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2034 // should pass zombie_ok == true.
2035 void nmethodLocker::lock_nmethod(CompiledMethod* cm, bool zombie_ok) {
2036   if (cm == NULL)  return;
2037   if (cm->is_aot()) return;  // FIXME: Revisit once _lock_count is added to aot_method
2038   nmethod* nm = cm->as_nmethod();
2039   Atomic::inc(&nm->_lock_count);
2040   assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2041 }
2042 
2043 void nmethodLocker::unlock_nmethod(CompiledMethod* cm) {
2044   if (cm == NULL)  return;
2045   if (cm->is_aot()) return;  // FIXME: Revisit once _lock_count is added to aot_method
2046   nmethod* nm = cm->as_nmethod();
2047   Atomic::dec(&nm->_lock_count);
2048   assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2049 }
2050 
2051 
2052 // -----------------------------------------------------------------------------
2053 // Verification
2054 
2055 class VerifyOopsClosure: public OopClosure {
2056   nmethod* _nm;
2057   bool     _ok;
2058 public:
2059   VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2060   bool ok() { return _ok; }
2061   virtual void do_oop(oop* p) {
2062     if (oopDesc::is_oop_or_null(*p)) return;
2063     if (_ok) {
2064       _nm->print_nmethod(true);
2065       _ok = false;
2066     }
2067     tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2068                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2069   }
2070   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2071 };
2072 
2073 void nmethod::verify() {
2074 
2075   // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2076   // seems odd.
2077 
2078   if (is_zombie() || is_not_entrant() || is_unloaded())
2079     return;
2080 
2081   // Make sure all the entry points are correctly aligned for patching.
2082   NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2083 
2084   // assert(oopDesc::is_oop(method()), "must be valid");
2085 
2086   ResourceMark rm;
2087 
2088   if (!CodeCache::contains(this)) {
2089     fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2090   }
2091 
2092   if(is_native_method() )
2093     return;
2094 
2095   nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2096   if (nm != this) {
2097     fatal("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2098   }
2099 
2100   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2101     if (! p->verify(this)) {
2102       tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2103     }
2104   }
2105 
2106   VerifyOopsClosure voc(this);
2107   oops_do(&voc);
2108   assert(voc.ok(), "embedded oops must be OK");
2109   Universe::heap()->verify_nmethod(this);
2110 
2111   verify_scopes();
2112 }
2113 
2114 
2115 void nmethod::verify_interrupt_point(address call_site) {
2116   // Verify IC only when nmethod installation is finished.
2117   if (!is_not_installed()) {
2118     Thread *cur = Thread::current();
2119     if (CompiledIC_lock->owner() == cur ||
2120         ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2121          SafepointSynchronize::is_at_safepoint())) {
2122       CompiledIC_at(this, call_site);
2123       CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2124     } else {
2125       MutexLocker ml_verify (CompiledIC_lock);
2126       CompiledIC_at(this, call_site);
2127     }
2128   }
2129 
2130   PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2131   assert(pd != NULL, "PcDesc must exist");
2132   for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2133                                      pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
2134                                      pd->return_oop());
2135        !sd->is_top(); sd = sd->sender()) {
2136     sd->verify();
2137   }
2138 }
2139 
2140 void nmethod::verify_scopes() {
2141   if( !method() ) return;       // Runtime stubs have no scope
2142   if (method()->is_native()) return; // Ignore stub methods.
2143   // iterate through all interrupt point
2144   // and verify the debug information is valid.
2145   RelocIterator iter((nmethod*)this);
2146   while (iter.next()) {
2147     address stub = NULL;
2148     switch (iter.type()) {
2149       case relocInfo::virtual_call_type:
2150         verify_interrupt_point(iter.addr());
2151         break;
2152       case relocInfo::opt_virtual_call_type:
2153         stub = iter.opt_virtual_call_reloc()->static_stub(false);
2154         verify_interrupt_point(iter.addr());
2155         break;
2156       case relocInfo::static_call_type:
2157         stub = iter.static_call_reloc()->static_stub(false);
2158         //verify_interrupt_point(iter.addr());
2159         break;
2160       case relocInfo::runtime_call_type:
2161       case relocInfo::runtime_call_w_cp_type: {
2162         address destination = iter.reloc()->value();
2163         // Right now there is no way to find out which entries support
2164         // an interrupt point.  It would be nice if we had this
2165         // information in a table.
2166         break;
2167       }
2168       default:
2169         break;
2170     }
2171     assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2172   }
2173 }
2174 
2175 
2176 // -----------------------------------------------------------------------------
2177 // Non-product code
2178 #ifndef PRODUCT
2179 
2180 class DebugScavengeRoot: public OopClosure {
2181   nmethod* _nm;
2182   bool     _ok;
2183 public:
2184   DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2185   bool ok() { return _ok; }
2186   virtual void do_oop(oop* p) {
2187     if ((*p) == NULL || !Universe::heap()->is_scavengable(*p))  return;
2188     if (_ok) {
2189       _nm->print_nmethod(true);
2190       _ok = false;
2191     }
2192     tty->print_cr("*** scavengable oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2193                   p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2194     (*p)->print();
2195   }
2196   virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2197 };
2198 
2199 void nmethod::verify_scavenge_root_oops() {
2200   if (!on_scavenge_root_list()) {
2201     // Actually look inside, to verify the claim that it's clean.
2202     DebugScavengeRoot debug_scavenge_root(this);
2203     oops_do(&debug_scavenge_root);
2204     if (!debug_scavenge_root.ok())
2205       fatal("found an unadvertised bad scavengable oop in the code cache");
2206   }
2207   assert(scavenge_root_not_marked(), "");
2208 }
2209 
2210 #endif // PRODUCT
2211 
2212 // Printing operations
2213 
2214 void nmethod::print() const {
2215   ResourceMark rm;
2216   ttyLocker ttyl;   // keep the following output all in one block
2217 
2218   tty->print("Compiled method ");
2219 
2220   if (is_compiled_by_c1()) {
2221     tty->print("(c1) ");
2222   } else if (is_compiled_by_c2()) {
2223     tty->print("(c2) ");
2224   } else if (is_compiled_by_jvmci()) {
2225     tty->print("(JVMCI) ");
2226   } else {
2227     tty->print("(nm) ");
2228   }
2229 
2230   print_on(tty, NULL);
2231 
2232   if (WizardMode) {
2233     tty->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
2234     tty->print(" for method " INTPTR_FORMAT , p2i(method()));
2235     tty->print(" { ");
2236     tty->print_cr("%s ", state());
2237     if (on_scavenge_root_list())  tty->print("scavenge_root ");
2238     tty->print_cr("}:");
2239   }
2240   if (size              () > 0) tty->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2241                                               p2i(this),
2242                                               p2i(this) + size(),
2243                                               size());
2244   if (relocation_size   () > 0) tty->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2245                                               p2i(relocation_begin()),
2246                                               p2i(relocation_end()),
2247                                               relocation_size());
2248   if (consts_size       () > 0) tty->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2249                                               p2i(consts_begin()),
2250                                               p2i(consts_end()),
2251                                               consts_size());
2252   if (insts_size        () > 0) tty->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2253                                               p2i(insts_begin()),
2254                                               p2i(insts_end()),
2255                                               insts_size());
2256   if (stub_size         () > 0) tty->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2257                                               p2i(stub_begin()),
2258                                               p2i(stub_end()),
2259                                               stub_size());
2260   if (oops_size         () > 0) tty->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2261                                               p2i(oops_begin()),
2262                                               p2i(oops_end()),
2263                                               oops_size());
2264   if (metadata_size      () > 0) tty->print_cr(" metadata       [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2265                                               p2i(metadata_begin()),
2266                                               p2i(metadata_end()),
2267                                               metadata_size());
2268   if (scopes_data_size  () > 0) tty->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2269                                               p2i(scopes_data_begin()),
2270                                               p2i(scopes_data_end()),
2271                                               scopes_data_size());
2272   if (scopes_pcs_size   () > 0) tty->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2273                                               p2i(scopes_pcs_begin()),
2274                                               p2i(scopes_pcs_end()),
2275                                               scopes_pcs_size());
2276   if (dependencies_size () > 0) tty->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2277                                               p2i(dependencies_begin()),
2278                                               p2i(dependencies_end()),
2279                                               dependencies_size());
2280   if (handler_table_size() > 0) tty->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2281                                               p2i(handler_table_begin()),
2282                                               p2i(handler_table_end()),
2283                                               handler_table_size());
2284   if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2285                                               p2i(nul_chk_table_begin()),
2286                                               p2i(nul_chk_table_end()),
2287                                               nul_chk_table_size());
2288 }
2289 
2290 #ifndef PRODUCT
2291 
2292 void nmethod::print_scopes() {
2293   // Find the first pc desc for all scopes in the code and print it.
2294   ResourceMark rm;
2295   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2296     if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2297       continue;
2298 
2299     ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2300     while (sd != NULL) {
2301       sd->print_on(tty, p);
2302       sd = sd->sender();
2303     }
2304   }
2305 }
2306 
2307 void nmethod::print_dependencies() {
2308   ResourceMark rm;
2309   ttyLocker ttyl;   // keep the following output all in one block
2310   tty->print_cr("Dependencies:");
2311   for (Dependencies::DepStream deps(this); deps.next(); ) {
2312     deps.print_dependency();
2313     Klass* ctxk = deps.context_type();
2314     if (ctxk != NULL) {
2315       if (ctxk->is_instance_klass() && InstanceKlass::cast(ctxk)->is_dependent_nmethod(this)) {
2316         tty->print_cr("   [nmethod<=klass]%s", ctxk->external_name());
2317       }
2318     }
2319     deps.log_dependency();  // put it into the xml log also
2320   }
2321 }
2322 
2323 
2324 void nmethod::print_relocations() {
2325   ResourceMark m;       // in case methods get printed via the debugger
2326   tty->print_cr("relocations:");
2327   RelocIterator iter(this);
2328   iter.print();
2329 }
2330 
2331 
2332 void nmethod::print_pcs() {
2333   ResourceMark m;       // in case methods get printed via debugger
2334   tty->print_cr("pc-bytecode offsets:");
2335   for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2336     p->print(this);
2337   }
2338 }
2339 
2340 void nmethod::print_recorded_oops() {
2341   tty->print_cr("Recorded oops:");
2342   for (int i = 0; i < oops_count(); i++) {
2343     oop o = oop_at(i);
2344     tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(o));
2345     if (o == Universe::non_oop_word()) {
2346       tty->print("non-oop word");
2347     } else {
2348       if (o != NULL) {
2349         o->print_value();
2350       } else {
2351         tty->print_cr("NULL");
2352       }
2353     }
2354     tty->cr();
2355   }
2356 }
2357 
2358 void nmethod::print_recorded_metadata() {
2359   tty->print_cr("Recorded metadata:");
2360   for (int i = 0; i < metadata_count(); i++) {
2361     Metadata* m = metadata_at(i);
2362     tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(m));
2363     if (m == (Metadata*)Universe::non_oop_word()) {
2364       tty->print("non-metadata word");
2365     } else {
2366       Metadata::print_value_on_maybe_null(tty, m);
2367     }
2368     tty->cr();
2369   }
2370 }
2371 
2372 #endif // PRODUCT
2373 
2374 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2375   RelocIterator iter(this, begin, end);
2376   bool have_one = false;
2377   while (iter.next()) {
2378     have_one = true;
2379     switch (iter.type()) {
2380         case relocInfo::none:                  return "no_reloc";
2381         case relocInfo::oop_type: {
2382           stringStream st;
2383           oop_Relocation* r = iter.oop_reloc();
2384           oop obj = r->oop_value();
2385           st.print("oop(");
2386           if (obj == NULL) st.print("NULL");
2387           else obj->print_value_on(&st);
2388           st.print(")");
2389           return st.as_string();
2390         }
2391         case relocInfo::metadata_type: {
2392           stringStream st;
2393           metadata_Relocation* r = iter.metadata_reloc();
2394           Metadata* obj = r->metadata_value();
2395           st.print("metadata(");
2396           if (obj == NULL) st.print("NULL");
2397           else obj->print_value_on(&st);
2398           st.print(")");
2399           return st.as_string();
2400         }
2401         case relocInfo::runtime_call_type:
2402         case relocInfo::runtime_call_w_cp_type: {
2403           stringStream st;
2404           st.print("runtime_call");
2405           CallRelocation* r = (CallRelocation*)iter.reloc();
2406           address dest = r->destination();
2407           CodeBlob* cb = CodeCache::find_blob(dest);
2408           if (cb != NULL) {
2409             st.print(" %s", cb->name());
2410           } else {
2411             ResourceMark rm;
2412             const int buflen = 1024;
2413             char* buf = NEW_RESOURCE_ARRAY(char, buflen);
2414             int offset;
2415             if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
2416               st.print(" %s", buf);
2417               if (offset != 0) {
2418                 st.print("+%d", offset);
2419               }
2420             }
2421           }
2422           return st.as_string();
2423         }
2424         case relocInfo::virtual_call_type: {
2425           stringStream st;
2426           st.print_raw("virtual_call");
2427           virtual_call_Relocation* r = iter.virtual_call_reloc();
2428           Method* m = r->method_value();
2429           if (m != NULL) {
2430             assert(m->is_method(), "");
2431             m->print_short_name(&st);
2432           }
2433           return st.as_string();
2434         }
2435         case relocInfo::opt_virtual_call_type: {
2436           stringStream st;
2437           st.print_raw("optimized virtual_call");
2438           opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
2439           Method* m = r->method_value();
2440           if (m != NULL) {
2441             assert(m->is_method(), "");
2442             m->print_short_name(&st);
2443           }
2444           return st.as_string();
2445         }
2446         case relocInfo::static_call_type: {
2447           stringStream st;
2448           st.print_raw("static_call");
2449           static_call_Relocation* r = iter.static_call_reloc();
2450           Method* m = r->method_value();
2451           if (m != NULL) {
2452             assert(m->is_method(), "");
2453             m->print_short_name(&st);
2454           }
2455           return st.as_string();
2456         }
2457         case relocInfo::static_stub_type:      return "static_stub";
2458         case relocInfo::external_word_type:    return "external_word";
2459         case relocInfo::internal_word_type:    return "internal_word";
2460         case relocInfo::section_word_type:     return "section_word";
2461         case relocInfo::poll_type:             return "poll";
2462         case relocInfo::poll_return_type:      return "poll_return";
2463         case relocInfo::type_mask:             return "type_bit_mask";
2464 
2465         default:
2466           break;
2467     }
2468   }
2469   return have_one ? "other" : NULL;
2470 }
2471 
2472 // Return a the last scope in (begin..end]
2473 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2474   PcDesc* p = pc_desc_near(begin+1);
2475   if (p != NULL && p->real_pc(this) <= end) {
2476     return new ScopeDesc(this, p->scope_decode_offset(),
2477                          p->obj_decode_offset(), p->should_reexecute(), p->rethrow_exception(),
2478                          p->return_oop());
2479   }
2480   return NULL;
2481 }
2482 
2483 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2484   if (block_begin == entry_point())             stream->print_cr("[Entry Point]");
2485   if (block_begin == verified_entry_point())    stream->print_cr("[Verified Entry Point]");
2486   if (JVMCI_ONLY(_exception_offset >= 0 &&) block_begin == exception_begin())         stream->print_cr("[Exception Handler]");
2487   if (block_begin == stub_begin())              stream->print_cr("[Stub Code]");
2488   if (JVMCI_ONLY(_deopt_handler_begin != NULL &&) block_begin == deopt_handler_begin())     stream->print_cr("[Deopt Handler Code]");
2489 
2490   if (has_method_handle_invokes())
2491     if (block_begin == deopt_mh_handler_begin())  stream->print_cr("[Deopt MH Handler Code]");
2492 
2493   if (block_begin == consts_begin())            stream->print_cr("[Constants]");
2494 
2495   if (block_begin == entry_point()) {
2496     methodHandle m = method();
2497     if (m.not_null()) {
2498       stream->print("  # ");
2499       m->print_value_on(stream);
2500       stream->cr();
2501     }
2502     if (m.not_null() && !is_osr_method()) {
2503       ResourceMark rm;
2504       int sizeargs = m->size_of_parameters();
2505       BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2506       VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2507       {
2508         int sig_index = 0;
2509         if (!m->is_static())
2510           sig_bt[sig_index++] = T_OBJECT; // 'this'
2511         for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2512           BasicType t = ss.type();
2513           sig_bt[sig_index++] = t;
2514           if (type2size[t] == 2) {
2515             sig_bt[sig_index++] = T_VOID;
2516           } else {
2517             assert(type2size[t] == 1, "size is 1 or 2");
2518           }
2519         }
2520         assert(sig_index == sizeargs, "");
2521       }
2522       const char* spname = "sp"; // make arch-specific?
2523       intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2524       int stack_slot_offset = this->frame_size() * wordSize;
2525       int tab1 = 14, tab2 = 24;
2526       int sig_index = 0;
2527       int arg_index = (m->is_static() ? 0 : -1);
2528       bool did_old_sp = false;
2529       for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2530         bool at_this = (arg_index == -1);
2531         bool at_old_sp = false;
2532         BasicType t = (at_this ? T_OBJECT : ss.type());
2533         assert(t == sig_bt[sig_index], "sigs in sync");
2534         if (at_this)
2535           stream->print("  # this: ");
2536         else
2537           stream->print("  # parm%d: ", arg_index);
2538         stream->move_to(tab1);
2539         VMReg fst = regs[sig_index].first();
2540         VMReg snd = regs[sig_index].second();
2541         if (fst->is_reg()) {
2542           stream->print("%s", fst->name());
2543           if (snd->is_valid())  {
2544             stream->print(":%s", snd->name());
2545           }
2546         } else if (fst->is_stack()) {
2547           int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2548           if (offset == stack_slot_offset)  at_old_sp = true;
2549           stream->print("[%s+0x%x]", spname, offset);
2550         } else {
2551           stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2552         }
2553         stream->print(" ");
2554         stream->move_to(tab2);
2555         stream->print("= ");
2556         if (at_this) {
2557           m->method_holder()->print_value_on(stream);
2558         } else {
2559           bool did_name = false;
2560           if (!at_this && ss.is_object()) {
2561             Symbol* name = ss.as_symbol_or_null();
2562             if (name != NULL) {
2563               name->print_value_on(stream);
2564               did_name = true;
2565             }
2566           }
2567           if (!did_name)
2568             stream->print("%s", type2name(t));
2569         }
2570         if (at_old_sp) {
2571           stream->print("  (%s of caller)", spname);
2572           did_old_sp = true;
2573         }
2574         stream->cr();
2575         sig_index += type2size[t];
2576         arg_index += 1;
2577         if (!at_this)  ss.next();
2578       }
2579       if (!did_old_sp) {
2580         stream->print("  # ");
2581         stream->move_to(tab1);
2582         stream->print("[%s+0x%x]", spname, stack_slot_offset);
2583         stream->print("  (%s of caller)", spname);
2584         stream->cr();
2585       }
2586     }
2587   }
2588 }
2589 
2590 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2591   // First, find an oopmap in (begin, end].
2592   // We use the odd half-closed interval so that oop maps and scope descs
2593   // which are tied to the byte after a call are printed with the call itself.
2594   address base = code_begin();
2595   ImmutableOopMapSet* oms = oop_maps();
2596   if (oms != NULL) {
2597     for (int i = 0, imax = oms->count(); i < imax; i++) {
2598       const ImmutableOopMapPair* pair = oms->pair_at(i);
2599       const ImmutableOopMap* om = pair->get_from(oms);
2600       address pc = base + pair->pc_offset();
2601       if (pc > begin) {
2602         if (pc <= end) {
2603           st->move_to(column);
2604           st->print("; ");
2605           om->print_on(st);
2606         }
2607         break;
2608       }
2609     }
2610   }
2611 
2612   // Print any debug info present at this pc.
2613   ScopeDesc* sd  = scope_desc_in(begin, end);
2614   if (sd != NULL) {
2615     st->move_to(column);
2616     if (sd->bci() == SynchronizationEntryBCI) {
2617       st->print(";*synchronization entry");
2618     } else if (sd->bci() == AfterBci) {
2619       st->print(";* method exit (unlocked if synchronized)");
2620     } else if (sd->bci() == UnwindBci) {
2621       st->print(";* unwind (locked if synchronized)");
2622     } else if (sd->bci() == AfterExceptionBci) {
2623       st->print(";* unwind (unlocked if synchronized)");
2624     } else if (sd->bci() == UnknownBci) {
2625       st->print(";* unknown");
2626     } else if (sd->bci() == InvalidFrameStateBci) {
2627       st->print(";* invalid frame state");
2628     } else {
2629       if (sd->method() == NULL) {
2630         st->print("method is NULL");
2631       } else if (sd->method()->is_native()) {
2632         st->print("method is native");
2633       } else {
2634         Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2635         st->print(";*%s", Bytecodes::name(bc));
2636         switch (bc) {
2637         case Bytecodes::_invokevirtual:
2638         case Bytecodes::_invokespecial:
2639         case Bytecodes::_invokestatic:
2640         case Bytecodes::_invokeinterface:
2641           {
2642             Bytecode_invoke invoke(sd->method(), sd->bci());
2643             st->print(" ");
2644             if (invoke.name() != NULL)
2645               invoke.name()->print_symbol_on(st);
2646             else
2647               st->print("<UNKNOWN>");
2648             break;
2649           }
2650         case Bytecodes::_getfield:
2651         case Bytecodes::_putfield:
2652         case Bytecodes::_getstatic:
2653         case Bytecodes::_putstatic:
2654           {
2655             Bytecode_field field(sd->method(), sd->bci());
2656             st->print(" ");
2657             if (field.name() != NULL)
2658               field.name()->print_symbol_on(st);
2659             else
2660               st->print("<UNKNOWN>");
2661           }
2662         default:
2663           break;
2664         }
2665       }
2666       st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
2667     }
2668 
2669     // Print all scopes
2670     for (;sd != NULL; sd = sd->sender()) {
2671       st->move_to(column);
2672       st->print("; -");
2673       if (sd->method() == NULL) {
2674         st->print("method is NULL");
2675       } else {
2676         sd->method()->print_short_name(st);
2677       }
2678       int lineno = sd->method()->line_number_from_bci(sd->bci());
2679       if (lineno != -1) {
2680         st->print("@%d (line %d)", sd->bci(), lineno);
2681       } else {
2682         st->print("@%d", sd->bci());
2683       }
2684       st->cr();
2685     }
2686   }
2687 
2688   // Print relocation information
2689   const char* str = reloc_string_for(begin, end);
2690   if (str != NULL) {
2691     if (sd != NULL) st->cr();
2692     st->move_to(column);
2693     st->print(";   {%s}", str);
2694   }
2695   int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2696   if (cont_offset != 0) {
2697     st->move_to(column);
2698     st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
2699   }
2700 
2701 }
2702 
2703 class DirectNativeCallWrapper: public NativeCallWrapper {
2704 private:
2705   NativeCall* _call;
2706 
2707 public:
2708   DirectNativeCallWrapper(NativeCall* call) : _call(call) {}
2709 
2710   virtual address destination() const { return _call->destination(); }
2711   virtual address instruction_address() const { return _call->instruction_address(); }
2712   virtual address next_instruction_address() const { return _call->next_instruction_address(); }
2713   virtual address return_address() const { return _call->return_address(); }
2714 
2715   virtual address get_resolve_call_stub(bool is_optimized) const {
2716     if (is_optimized) {
2717       return SharedRuntime::get_resolve_opt_virtual_call_stub();
2718     }
2719     return SharedRuntime::get_resolve_virtual_call_stub();
2720   }
2721 
2722   virtual void set_destination_mt_safe(address dest) {
2723 #if INCLUDE_AOT
2724     if (UseAOT) {
2725       CodeBlob* callee = CodeCache::find_blob(dest);
2726       CompiledMethod* cm = callee->as_compiled_method_or_null();
2727       if (cm != NULL && cm->is_far_code()) {
2728         // Temporary fix, see JDK-8143106
2729         CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
2730         csc->set_to_far(methodHandle(cm->method()), dest);
2731         return;
2732       }
2733     }
2734 #endif
2735     _call->set_destination_mt_safe(dest);
2736   }
2737 
2738   virtual void set_to_interpreted(const methodHandle& method, CompiledICInfo& info) {
2739     CompiledDirectStaticCall* csc = CompiledDirectStaticCall::at(instruction_address());
2740 #if INCLUDE_AOT
2741     if (info.to_aot()) {
2742       csc->set_to_far(method, info.entry());
2743     } else
2744 #endif
2745     {
2746       csc->set_to_interpreted(method, info.entry());
2747     }
2748   }
2749 
2750   virtual void verify() const {
2751     // make sure code pattern is actually a call imm32 instruction
2752     _call->verify();
2753     _call->verify_alignment();
2754   }
2755 
2756   virtual void verify_resolve_call(address dest) const {
2757     CodeBlob* db = CodeCache::find_blob_unsafe(dest);
2758     assert(db != NULL && !db->is_adapter_blob(), "must use stub!");
2759   }
2760 
2761   virtual bool is_call_to_interpreted(address dest) const {
2762     CodeBlob* cb = CodeCache::find_blob(_call->instruction_address());
2763     return cb->contains(dest);
2764   }
2765 
2766   virtual bool is_safe_for_patching() const { return false; }
2767 
2768   virtual NativeInstruction* get_load_instruction(virtual_call_Relocation* r) const {
2769     return nativeMovConstReg_at(r->cached_value());
2770   }
2771 
2772   virtual void *get_data(NativeInstruction* instruction) const {
2773     return (void*)((NativeMovConstReg*) instruction)->data();
2774   }
2775 
2776   virtual void set_data(NativeInstruction* instruction, intptr_t data) {
2777     ((NativeMovConstReg*) instruction)->set_data(data);
2778   }
2779 };
2780 
2781 NativeCallWrapper* nmethod::call_wrapper_at(address call) const {
2782   return new DirectNativeCallWrapper((NativeCall*) call);
2783 }
2784 
2785 NativeCallWrapper* nmethod::call_wrapper_before(address return_pc) const {
2786   return new DirectNativeCallWrapper(nativeCall_before(return_pc));
2787 }
2788 
2789 address nmethod::call_instruction_address(address pc) const {
2790   if (NativeCall::is_call_before(pc)) {
2791     NativeCall *ncall = nativeCall_before(pc);
2792     return ncall->instruction_address();
2793   }
2794   return NULL;
2795 }
2796 
2797 CompiledStaticCall* nmethod::compiledStaticCall_at(Relocation* call_site) const {
2798   return CompiledDirectStaticCall::at(call_site);
2799 }
2800 
2801 CompiledStaticCall* nmethod::compiledStaticCall_at(address call_site) const {
2802   return CompiledDirectStaticCall::at(call_site);
2803 }
2804 
2805 CompiledStaticCall* nmethod::compiledStaticCall_before(address return_addr) const {
2806   return CompiledDirectStaticCall::before(return_addr);
2807 }
2808 
2809 #ifndef PRODUCT
2810 
2811 void nmethod::print_value_on(outputStream* st) const {
2812   st->print("nmethod");
2813   print_on(st, NULL);
2814 }
2815 
2816 void nmethod::print_calls(outputStream* st) {
2817   RelocIterator iter(this);
2818   while (iter.next()) {
2819     switch (iter.type()) {
2820     case relocInfo::virtual_call_type:
2821     case relocInfo::opt_virtual_call_type: {
2822       VerifyMutexLocker mc(CompiledIC_lock);
2823       CompiledIC_at(&iter)->print();
2824       break;
2825     }
2826     case relocInfo::static_call_type:
2827       st->print_cr("Static call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
2828       CompiledDirectStaticCall::at(iter.reloc())->print();
2829       break;
2830     default:
2831       break;
2832     }
2833   }
2834 }
2835 
2836 void nmethod::print_handler_table() {
2837   ExceptionHandlerTable(this).print();
2838 }
2839 
2840 void nmethod::print_nul_chk_table() {
2841   ImplicitExceptionTable(this).print(code_begin());
2842 }
2843 
2844 void nmethod::print_statistics() {
2845   ttyLocker ttyl;
2846   if (xtty != NULL)  xtty->head("statistics type='nmethod'");
2847   native_nmethod_stats.print_native_nmethod_stats();
2848 #ifdef COMPILER1
2849   c1_java_nmethod_stats.print_nmethod_stats("C1");
2850 #endif
2851 #ifdef COMPILER2
2852   c2_java_nmethod_stats.print_nmethod_stats("C2");
2853 #endif
2854 #if INCLUDE_JVMCI
2855   jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
2856 #endif
2857   unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
2858   DebugInformationRecorder::print_statistics();
2859 #ifndef PRODUCT
2860   pc_nmethod_stats.print_pc_stats();
2861 #endif
2862   Dependencies::print_statistics();
2863   if (xtty != NULL)  xtty->tail("statistics");
2864 }
2865 
2866 #endif // !PRODUCT
2867 
2868 #if INCLUDE_JVMCI
2869 void nmethod::clear_jvmci_installed_code() {
2870   assert_locked_or_safepoint(Patching_lock);
2871   if (_jvmci_installed_code != NULL) {
2872     JNIHandles::destroy_weak_global(_jvmci_installed_code);
2873     _jvmci_installed_code = NULL;
2874   }
2875 }
2876 
2877 void nmethod::clear_speculation_log() {
2878   assert_locked_or_safepoint(Patching_lock);
2879   if (_speculation_log != NULL) {
2880     JNIHandles::destroy_weak_global(_speculation_log);
2881     _speculation_log = NULL;
2882   }
2883 }
2884 
2885 void nmethod::maybe_invalidate_installed_code() {
2886   assert(Patching_lock->is_locked() ||
2887          SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency");
2888   oop installed_code = JNIHandles::resolve(_jvmci_installed_code);
2889   if (installed_code != NULL) {
2890     // Update the values in the InstalledCode instance if it still refers to this nmethod
2891     nmethod* nm = (nmethod*)InstalledCode::address(installed_code);
2892     if (nm == this) {
2893       if (!is_alive()) {
2894         // Break the link between nmethod and InstalledCode such that the nmethod
2895         // can subsequently be flushed safely.  The link must be maintained while
2896         // the method could have live activations since invalidateInstalledCode
2897         // might want to invalidate all existing activations.
2898         InstalledCode::set_address(installed_code, 0);
2899         InstalledCode::set_entryPoint(installed_code, 0);
2900       } else if (is_not_entrant()) {
2901         // Remove the entry point so any invocation will fail but keep
2902         // the address link around that so that existing activations can
2903         // be invalidated.
2904         InstalledCode::set_entryPoint(installed_code, 0);
2905       }
2906     }
2907   }
2908   if (!is_alive()) {
2909     // Clear these out after the nmethod has been unregistered and any
2910     // updates to the InstalledCode instance have been performed.
2911     clear_jvmci_installed_code();
2912     clear_speculation_log();
2913   }
2914 }
2915 
2916 void nmethod::invalidate_installed_code(Handle installedCode, TRAPS) {
2917   if (installedCode() == NULL) {
2918     THROW(vmSymbols::java_lang_NullPointerException());
2919   }
2920   jlong nativeMethod = InstalledCode::address(installedCode);
2921   nmethod* nm = (nmethod*)nativeMethod;
2922   if (nm == NULL) {
2923     // Nothing to do
2924     return;
2925   }
2926 
2927   nmethodLocker nml(nm);
2928 #ifdef ASSERT
2929   {
2930     MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
2931     // This relationship can only be checked safely under a lock
2932     assert(!nm->is_alive() || nm->jvmci_installed_code() == installedCode(), "sanity check");
2933   }
2934 #endif
2935 
2936   if (nm->is_alive()) {
2937     // Invalidating the InstalledCode means we want the nmethod
2938     // to be deoptimized.
2939     nm->mark_for_deoptimization();
2940     VM_Deoptimize op;
2941     VMThread::execute(&op);
2942   }
2943 
2944   // Multiple threads could reach this point so we now need to
2945   // lock and re-check the link to the nmethod so that only one
2946   // thread clears it.
2947   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
2948   if (InstalledCode::address(installedCode) == nativeMethod) {
2949       InstalledCode::set_address(installedCode, 0);
2950   }
2951 }
2952 
2953 oop nmethod::jvmci_installed_code() {
2954   return JNIHandles::resolve(_jvmci_installed_code);
2955 }
2956 
2957 oop nmethod::speculation_log() {
2958   return JNIHandles::resolve(_speculation_log);
2959 }
2960 
2961 char* nmethod::jvmci_installed_code_name(char* buf, size_t buflen) const {
2962   if (!this->is_compiled_by_jvmci()) {
2963     return NULL;
2964   }
2965   oop installed_code = JNIHandles::resolve(_jvmci_installed_code);
2966   if (installed_code != NULL) {
2967     oop installed_code_name = NULL;
2968     if (installed_code->is_a(InstalledCode::klass())) {
2969       installed_code_name = InstalledCode::name(installed_code);
2970     }
2971     if (installed_code_name != NULL) {
2972       return java_lang_String::as_utf8_string(installed_code_name, buf, (int)buflen);
2973     }
2974   }
2975   return NULL;
2976 }
2977 #endif